UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

Filed by the Registrant  ☒                            Filed by a Party other than the Registrant  ☐

Check the appropriate box:

ESTERLINE TECHNOLOGIES CORPORATION

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check the appropriate box):

PRELIMINARY PROXY STATEMENT—SUBJECT TO COMPLETION

DATED NOVEMBER 7, 2018

MERGER PROPOSAL—YOUR VOTE IS VERY IMPORTANT

[●],November 30, 2018

To the Shareholders of Esterline Technologies Corporation:

You are cordially invited to attend a Special Meeting of Shareholders (the “Special Meeting”) of Esterline Technologies Corporation, a Delaware corporation (“ESL”), which is scheduled to be held at [●]the Seattle offices of Perkins Coie LLP, 1201 Third Avenue, Suite 4900, Seattle, Washington on [●], 2018,January 17, 2019, at [●] time.10:30 a.m. Pacific Time.

At the Special Meeting, you will be asked to consider and vote upon a proposal to adopt the Agreement and Plan of Merger, dated as of October 9, 2018 and amended on October 10, 2018 (as it may be further amended from time to time, the “Merger Agreement”), by and among ESL, TransDigm Group Incorporated, a Delaware corporation (“TransDigm”), and Thunderbird Merger Sub Inc., a Delaware corporation and wholly owned subsidiary of TransDigm (“Merger Sub”). Pursuant to the terms of the Merger Agreement, Merger Sub will merge with and into ESL, with ESL surviving the merger as a wholly owned subsidiary of TransDigm (the “Merger”). You also will be asked to consider and vote on (i) anon-binding advisory proposal to approve compensation that will or may become payable by ESL to its named executive officers in connection with the merger and (ii) a proposal to approve one or more adjournments of the Special Meeting to a later date or dates, if necessary or appropriate, to solicit additional proxies if there are insufficient votes to adopt the Merger Agreement at the time of the Special Meeting.

If the Merger is completed, you will be entitled to receive $122.50 in cash, without interest and subject to any withholding taxes, for each share of our common stock, par value $0.20, which we refer to as ESL common stock, you own (unless you have properly exercised and perfected your appraisal rights with respect to such shares), which represents a premium of approximately (i) 62% to the closing stock price of ESL common stock on July 19, 2018, the last trading day prior to market rumors regarding a potential sale of ESL, (ii) 22% to the highest stock price of ESL common stock during thefifty-two (52) week period ended July 19, 2018, the last trading day prior to market rumors regarding a potential sale of ESL, (iii) 67% to the volume weighted average stock price of ESL common stock during the thirty (30) days ended July 19, 2018, the last trading day prior to market rumors regarding a potential sale of ESL, (iv) 38% to the closing stock price on October 8, 2018, the last trading day prior to the announcement of the execution of the Merger Agreement and (v) 57% to the broker median price per share as of October 8, 2018, per IBES consensus.

The receipt of cash in exchange for shares of ESL common stock pursuant to the Merger will generally be a taxable transaction to “U.S. holders” (as defined in “Proposal 1: Adoption of the Merger Agreement—The Merger—U.S. Federal Income Tax Consequences of the Merger”) for United States federal income tax purposes. See “Proposal 1: Adoption of the Merger Agreement—The Merger—U.S. Federal Income Tax Consequences of the Merger” beginning on page 60 of the accompanying proxy statement.

Shareholders who do not vote in favor of the proposal to adopt the Merger Agreement will have the right to seek appraisal of the fair value of their shares of ESL common stock if they deliver a demand for appraisal before the vote is taken on the Merger Agreement and comply with all applicable requirements under Delaware law, which are summarized and reproduced in their entirety in Annex C to the accompanying proxy statement.

ESL’s Board of Directors, after considering the reasons more fully described in this proxy statement and after consultation with outside legal and financial advisors, unanimously (1) determined that it is in the best interests of ESL and its shareholders and declared it advisable for ESL to enter into the Merger Agreement, (2) approved the execution, delivery and performance by ESL of the Merger Agreement and the consummation of the Merger and the other transactions contemplated by the Merger Agreement, (3) directed that the adoption of the Merger Agreement be submitted to a vote of ESL’s shareholders at the Special Meeting and (4) resolved to recommend that the ESL shareholders approve the adoption of the

Merger Agreement and the transactions contemplated therein, including the Merger. The Board of Directors recommends that you vote:

(i) “FOR” the proposal to adopt the Merger Agreement, thereby approving the transactions contemplated by the Merger Agreement, including the Merger;

(ii) “FOR” the proposal to approve, by anon-binding, advisory vote, compensation that will or may become payable by ESL to its named executive officers in connection with the Merger; and

(iii) “FOR” the proposal to approve one or more adjournments of the Special Meeting to a later date or dates, if necessary or appropriate, to solicit additional proxies if there are insufficient votes to adopt the Merger Agreement at the time of the Special Meeting.

The enclosed proxy statement provides detailed information about the Special Meeting, the Merger Agreement and the Merger. A copy of the Merger Agreement is attached as Annex A to the proxy statement. The proxy statement also describes the actions and determinations of our Board of Directors in connection with its evaluation of the Merger Agreement and the Merger. We encourage you to read the proxy statement and its annexes, including the Merger Agreement, carefully and in their entirety. You may also obtain more information about ESL from documents we file with the Securities and Exchange Commission from time to time.

Whether or not you plan to attend the Special Meeting in person, please complete, sign, date and return, as promptly as possible, the enclosed proxy card in the accompanying prepaid reply envelope or grant your proxy electronically over the Internet or by telephone. If you attend the Special Meeting and vote in person by ballot, your vote will revoke any proxy that you have previously submitted. If you hold your shares in “street name,” you should instruct your broker, bank or other nominee how to vote in accordance with the voting instruction form you will receive from your broker, bank or other nominee.

Your vote is very important, regardless of the number of shares that you own. We cannot complete the Merger unless the proposal to adopt the Merger Agreement is approved by the affirmative vote of the holders of a majority of the outstanding shares of ESL common stock. The failure of any shareholder to vote in person by ballot at the Special Meeting, to submit a signed proxy card or to grant a proxy electronically over the Internet or by telephone will have the same effect as a vote “AGAINST” the proposal to adopt the Merger Agreement. If you hold your shares in “street name,” the failure to instruct your broker, bank or other nominee on how to vote your shares will have the same effect as a vote “AGAINST” the proposal to adopt the Merger Agreement.

If you have any questions or need assistance voting your shares of ESL common stock, please contact MacKenzie Partners, Inc., our proxy solicitor, by calling toll-free at (800)322-2885 or collect at (212)929-5500.

On behalf of our Board of Directors, I thank you for your support and appreciate your consideration of this matter.

Sincerely,

Curtis C. Reusser

Chairman, President and Chief Executive Officer

Neither the U.S. Securities and Exchange Commission nor any state securities regulatory agency has approved or disapproved of the transactions described in this document, including the Merger, or determined if the information contained in this document is accurate or adequate. Any representation to the contrary is a criminal offense.

The accompanying proxy statement is dated [●],November 30, 2018 and, together with the enclosed form of proxy card, is first being mailed to shareholders of ESL on or about [●],November 30, 2018.

PRELIMINARY PROXY STATEMENT — SUBJECT TO COMPLETION

DATED NOVEMBER 7, 2018

NOTICE OF SPECIAL MEETING OF SHAREHOLDERS

TO BE HELD ON [●], 2018JANUARY 17, 2019

Notice is hereby given that a special meeting of shareholders (the “Special Meeting”) of Esterline Technologies Corporation, a Delaware corporation (“ESL”), is scheduled to be held at [●]the Seattle offices of Perkins Coie LLP, 1201 Third Avenue, Suite 4900, Seattle, Washington on [●], 2018,January 17, 2019, at [●] time10:30 a.m. Pacific Time for the following purposes:

Your vote is very important to us. The Merger is conditioned on the receipt of, and we cannot consummate the Merger unless the Merger Proposal receives, the affirmative vote of a majority of the outstanding shares of ESL common stock entitled to vote at the Special Meeting.

ESL will transact no other business at the Special Meeting.

The affirmative vote of a majority of the shares of ESL common stock outstanding and entitled to vote is required to approve the Merger Proposal. The affirmative vote of a majority of the votes cast at the Special Meeting is required to approve the Merger-Related Compensation Proposal, provided a quorum is present. The affirmative vote of a majority of the votes cast at the Special Meeting is required to approve the ESL Adjournment Proposal, whether or not a quorum is present.

The failure of any shareholder of record to submit a signed proxy card, grant a proxy electronically over the Internet or by telephone or to vote in person by ballot at the Special Meeting will have the same effect as a vote “AGAINST” the Merger Proposal, but will not have any effect on the ESL Adjournment Proposal or the Merger-Related Compensation Proposal. If you hold your shares in “street name,” the failure to instruct your broker, bank or other nominee on how to vote your shares will have the same effect as a vote “AGAINST” the Merger Proposal, but will not have any effect on the Merger-Related Compensation Proposal or the ESL Adjournment Proposal. Abstentions will have the same effect as a vote “AGAINST” the Merger Proposal, the ESL Adjournment Proposal and the Merger-Related Compensation Proposal.

Only shareholders of record as of the close of business on [●]November 29, 2018 are entitled to notice of the Special Meeting and to vote at the Special Meeting or at any adjournment or postponement thereof. A list of shareholders entitled to vote at the Special Meeting will be available in our offices located at 500 108^th Avenue N.E., Bellevue, Washington 98004 during regular business hours for a period of at least ten (10) days before the Special Meeting and at the place of the Special Meeting during the meeting.

Shareholders who do not vote in favor of the proposal to adopt the Merger Agreement will have the right to seek appraisal of the fair value of their shares of ESL common stock if they deliver a demand for appraisal before the vote is taken on the Merger Agreement and comply with all applicable requirements under Delaware law, which are summarized herein and reproduced in their entirety in Annex C to the accompanying proxy statement.

The Board of Directors recommends that you vote (i) “FOR” the Merger Proposal, (ii) “FOR” the Merger-Related Compensation Proposal and (iii) “FOR” the ESL Adjournment Proposal.

By Order of the Board of Directors,

Amy L. Watson

Deputy General Counsel and Corporate Secretary

Dated: [●],November 30, 2018

YOUR VOTE IS IMPORTANT

WHETHER OR NOT YOU EXPECT TO ATTEND THE SPECIAL MEETING IN PERSON, WE ENCOURAGE YOU TO SUBMIT YOUR PROXY AS PROMPTLY AS POSSIBLE (1) BY TELEPHONE, (2) THROUGH THE INTERNET OR (3) BY MARKING, SIGNING AND DATING THE ENCLOSED PROXY CARD AND RETURNING IT IN THE POSTAGE-PAID ENVELOPE PROVIDED. You may revoke your proxy or change your vote at any time before the special meeting. If your shares are held in the name of a broker, bank or other nominee, please follow the instructions on the voting instruction card furnished to you by such broker, bank or other nominee, which is considered the shareholder of record, in order to vote. As a beneficial owner, you have the right to direct your broker, bank or other nominee on how to vote the shares in your account. Your broker, bank or other nominee cannot vote on any of the proposals, including the proposal to adopt the Merger Agreement, without your instructions.

If you fail to return your proxy card, to grant your proxy electronically over the Internet or by telephone, or to vote by ballot in person at the special meeting, your shares will not be counted for purposes of determining whether a quorum is present at the special meeting. If you are a shareholder of record, voting in person by ballot at the special meeting will revoke any proxy that you previously submitted. If you hold your shares through a broker, bank or other nominee, you must obtain from the record holder a valid proxy issued in your name in order to vote in person at the special meeting.

We encourage you to read the accompanying proxy statement, including all documents incorporated by reference into the accompanying proxy statement, and annexes to the accompanying proxy statement, carefully and in their entirety. If you have any questions concerning the merger, the special meeting or the accompanying proxy statement, would like additional copies of the accompanying proxy statement or need help voting your shares of common stock, please contact our proxy solicitor:

MacKenzie Partners, Inc.

1407 Broadway

New York, NY 10018

(800)322-2885 (toll-free)

(212)929-5500 (collect)

proxy@mackenziepartners.com

TABLE OF CONTENTS

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QUESTIONS AND ANSWERS

The following questions and answers are intended to address some commonly asked questions regarding the merger, the merger agreement and the special meeting. These questions and answers may not address all questions that may be important to you as an ESL shareholder. We encourage you to read carefully the more detailed information contained elsewhere in this proxy statement, the annexes to this proxy statement, including the merger agreement, and the documents we incorporate by reference in this proxy statement. You may obtain the documents and information incorporated by reference in this proxy statement without charge by following the instructions under the section entitled “Where You Can Find More Information” beginning on page 101.102. The merger agreement is attached as Annex A to this proxy statement.

If you are a beneficial owner and hold your shares in “street name” through a broker, bank or other nominee, you should instruct your broker, bank or other nominee on how you wish to vote your shares of ESL common stock using the instructions provided by your broker, bank or other nominee. If you hold your shares in “street name,” because you are not the shareholder of record, you may not vote your shares in person at the special meeting unless you provide proof of ownership of ESL common stock, such as a recent bank or brokerage account statement, and you request and obtain a valid proxy from your broker, bank or other nominee.

“FOR” the merger proposal,

“FOR” the merger-related compensation proposal, and

“FOR” the adjournment proposal.

Under specified circumstances, ESL will be required to pay TransDigm a termination fee upon the termination of the merger agreement, as described under the section entitled “Proposal 1: Adoption of the Merger Agreement—Terms of the Merger Agreement—Termination of the Merger Agreement—Termination Fee” beginning on page 82.83.

The failure of any shareholder of record to submit a signed proxy card, grant a proxy electronically over the Internet or by telephone or to vote in person by ballot at the special meeting will have the same effect as a vote “AGAINST” the proposal to adopt the merger agreement. If you hold your shares in “street name,” the failure to instruct your broker, bank or other nominee on how to vote your shares will have the same effect as a vote “AGAINST” the proposal to adopt the merger agreement. An abstention will also have the same effect as a vote “AGAINST” the proposal to adopt the merger agreement.

Approval of the adjournment proposal, whether or not a quorum is present, requires the affirmative vote of a majority of the votes cast at the special meeting.

The failure of any shareholder of record to submit a signed proxy card, grant a proxy electronically over the Internet or by telephone or to vote in person by ballot at the special meeting will not have any effect on the merger-related compensation proposal or the adjournment proposal. If you hold your shares in “street name,” the failure to instruct your broker, bank or other nominee on how to vote your shares will not have any effect on the merger-related compensation proposal or the adjournment proposal. An abstention will have the same effect as a vote “AGAINST” the merger-related compensation proposal and the adjournment proposal.

Brokernon-votes are shares held by a broker, bank or other nominee that are present in person or represented by proxy at the special meeting, but with respect to which the broker, bank or other nominee is not instructed by the beneficial owner of such shares on how to vote on a particular proposal and the broker does not have discretionary voting power on such proposal. Because brokers, banks and other nominee holders of record do not have discretionary voting authority with respect to any of the three proposals, if a beneficial owner of shares of ESL common stock held in “street name” does not give voting instructions to the broker, bank or other nominee with respect to any of the proposals, then those shares will not be present in person or represented by proxy at the special meeting.

If your shares are held through a broker, bank or other nominee, you are considered the “beneficial owner” of the shares of ESL common stock held in “street name.” In that case, this proxy statement has been forwarded to you by your broker, bank or other nominee who is considered, with respect to those shares, to be the shareholder of record. As the beneficial owner, you have the right to direct your broker, bank or other nominee on how to vote your shares by following their instructions for voting. You are also invited to attend

the special meeting. However, because you are not the shareholder of record, you may not vote your shares in person at the special meeting unless you request and obtain a valid proxy from your broker, bank or other nominee.

A control number, located on your proxy card, is designed to verify your identity and allow you to vote your shares of ESL common stock, and to confirm that your voting instructions have been properly recorded when voting electronically over the Internet or by telephone. Please be aware that, although there is no charge for voting your shares, if you vote electronically over the Internet or by telephone, you may incur costs such as telephone and Internet access charges for which you will be responsible.

Even if you plan to attend the special meeting in person, you are strongly encouraged to vote your shares of ESL common stock by proxy. If you are a shareholder of record or if you obtain a valid proxy to vote shares which you beneficially own, you may still vote your shares of ESL common stock in person at the special meeting even if you have previously voted by proxy. If you are present at the special meeting and vote in person, your previous vote by proxy will not be counted.

If your shares are held in “street name” through a broker, bank or other nominee, you may vote through your broker, bank or other nominee by completing and returning the voting form provided by your broker, bank or other nominee, or electronically over the Internet or by telephone through your broker, bank or other nominee if such a service is provided. To vote via the Internet or via telephone through your broker, bank or other nominee, you should follow the instructions on the voting form provided by your broker, bank or other nominee.

Please note that to be effective, your new proxy card, Internet or telephonic voting instructions or written notice of revocation must be received by our Secretary prior to the special meeting and, in the case of Internet or telephonic voting instructions, must be received before 11:59 p.m., [●] timePacific Time on [●], 2018.January 16, 2019. If you have submitted a proxy, your appearance at the special meeting, in the absence of voting in person or submitting an additional proxy or revocation, will not have the effect of revoking your prior proxy.

If you hold your shares of ESL common stock in “street name,” you should contact your broker, bank or other nominee for instructions regarding how to change your vote. You may also vote in person at the special meeting if you obtain a valid proxy from your broker, bank or other nominee.

For a more complete description of the U.S. federal income tax consequences of the merger, see “Proposal 1: Adoption of the Merger Agreement—The Merger—U.S. Federal Income Tax Consequences of the Merger” beginning on page 60.

This proxy statement contains a general discussion of U.S. federal income tax consequences of the merger. This description does not address anynon-U.S. tax consequences, nor does it pertain to state, local or other tax consequences. Consequently, you are urged to contact your tax advisor to determine the particular tax consequences to you of the merger.

MacKenzie Partners, Inc.

1407 Broadway

New York, NY 10018

(800)322-2885 (toll-free)

(212)929-5500 (collect)

proxy@mackenziepartners.com

FORWARD-LOOKING STATEMENTS

This proxy statement, and the documents to which we refer you in this proxy statement, as well as information included in oral statements or other written statements made or to be made by us or on our behalf, contain “forward-looking statements” that do not directly or exclusively relate to historical facts. You can typically identify forward-looking statements by the use of forward-looking words, such as “may,” “can,” “could,” “should,” “will,” “would,” “might,” “see,” “seek,” “estimate,” “project,” “forecast,” “intend,” “expect,” “anticipate,” “believe,” “confident,” “continue,” “potential,” “target,” “goal,” “plan,” “strategy,” “prospect,” “predict,” “providing guidance” and similar expressions that are intended to identify information that is not historical in nature. Forward-looking statements by their nature address matters that are, to different degrees, uncertain, such as statements about the consummation of the proposed merger and the anticipated benefits thereof. These and other forward-looking statements are not guarantees of future results and are subject to risks, uncertainties and assumptions that could cause actual results to differ materially from those expressed in any forward-looking statements, including the failure to consummate the proposed merger or to make any filing or take other action required to consummate such merger in a timely matter or at all. The inclusion of such statements should not be regarded as a representation that any plans, estimates or expectations will be achieved.

These risks and uncertainties include, but are not limited to, the risks detailed in our filings with the SEC, including in our most recent filings on Form10-K and Amendment No. 1 on Form10-K/A and subsequent periodic and interim reports, factors and matters described or incorporated by reference in this proxy statement, and the following factors:

Consequences of material differences in results as compared with those anticipated in the forward-looking statements could include, among other things, business disruption, operational problems, financial loss, legal liability to third parties and similar risks, any of which could have a material adverse effect on ESL’s financial condition, results of operations, credit rating or liquidity.

There can be no assurance that the merger will be completed, or if it is completed, that it will close within the anticipated time period or that the expected benefits of the merger will be realized. Readers are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date on which such statements were made.

All of the forward-looking statements we make in this proxy statement are qualified by the information contained or incorporated by reference herein, including, but not limited to, (a) the information contained under this heading and (b) the information contained under the headings “Risk Factors” and information in our consolidated financial statements and notes thereto included in our most recent filings on Form10-K and Amendment No. 1 on Form10-K/A and subsequent periodic and interim report filings (see “Where You Can

Find More Information” beginning on page 101)102). No assurance can be given that these are all of the factors that could cause actual results to vary materially from the forward-looking statements. For all forward-looking statements, ESL claims the protection of the safe harbor for forward-looking statements contained in the U.S. Private Securities Litigation Reform Act of 1995.

Except as required by applicable law, we undertake no obligation to publicly update forward-looking statements, whether as a result of new information, future events or otherwise. ESL shareholders are advised, however, to consult any future disclosures we make on related subjects as may be detailed in our other filings made from time to time with the SEC.

THE SPECIAL MEETING

The enclosed proxy is solicited on behalf of the Board of Directors for use at the special meeting of shareholders or at any adjournments or postponements thereof.

Date, Time and Place

We have scheduled to hold the special meeting at [●]the Seattle offices of Perkins Coie LLP, 1201 Third Avenue, Suite 4900, Seattle, Washington on [●], 2018,January 17, 2019, at [●] time.10:30 a.m. Pacific Time.

Purpose of the Special Meeting

At the special meeting, we will ask our shareholders of record as of the record date to vote on the following proposals:

Proposal 1—Adoption of the Merger Agreement. To consider and vote on the merger proposal;

Proposal 2—Approval, on an Advisory(Non-Binding Basis), of Certain Compensatory Arrangements with Named Executive Officers. To consider and vote on the merger-related compensation proposal; and

Proposal 3—Adjournment of the Special Meeting. To consider and vote on the adjournment proposal.

Record Date; Shares Entitled to Vote; Quorum

Only shareholders of record as of the close of business on [●]November 29, 2018 are entitled to notice of the special meeting and to vote at the special meeting or at any adjournments or postponements thereof. A list of shareholders entitled to vote at the Special Meeting will be available in our offices located at 500 108^th Avenue N.E., Bellevue, Washington 98004 during regular business hours for a period of at least ten (10) days before the Special Meeting and at the place of the Special Meeting during the meeting.

As of the record date, there were approximately [●]29,518,042 shares of ESL common stock outstanding and entitled to be voted at the special meeting.

A quorum of shareholders is necessary to hold a vote for the merger proposal and the merger-related compensation proposal at the special meeting. The holders of a majority of the issued and outstanding shares of our common stock entitled to vote at the special meeting, either present in person or represented by proxy, will constitute a quorum at the special meeting. As a result, [●]14,759,022 shares must be represented by proxy or by shareholders present and entitled to vote at the special meeting to have a quorum.

In the event that a quorum is not present at the special meeting, it is expected that the meeting would be adjourned or postponed to a later date to solicit additional proxies.

Vote Required; Abstentions and BrokerNon-Votes

The affirmative vote of the holders of a majority of the outstanding shares of our common stock entitled to vote is required to approve the merger proposal. Adoption of the merger agreement by our shareholders is a condition to the closing of the merger.

Approval of the merger-related compensation proposal requires the affirmative vote of a majority of the votes cast at the special meeting, provided a quorum is present. Approval of the adjournment proposal requires the affirmative vote of a majority of the votes cast at the special meeting, whether or not a quorum is present.

If you abstain from voting, the abstention will have the same effect as if you voted “AGAINST” the merger proposal, the merger-related compensation proposal and the adjournment proposal.

If you hold your shares in “street name,” the failure to instruct your broker, bank or other nominee on how to vote your shares will count as a vote “AGAINST” the merger proposal, but will have no effect on the merger-related compensation proposal and the adjournment proposal.

Shares Held by ESL’s Directors and Executive Officers

As of the record date, ESL directors and executive officers beneficially owned and were entitled to vote, in the aggregate, [●]191,019 shares of ESL common stock (excluding any shares of ESL common stock that would be delivered upon exercise or conversion of stock options or other equity-based awards), which represented approximately [●]%0.65% of the outstanding shares of ESL common stock on that date. It is expected that ESL’s directors and executive officers will vote their shares “FOR” the adoption of the merger agreement, although none of them has entered into any agreement requiring them to do so.

Voting of Proxies

If your shares are registered in your name with our transfer agent, Computershare, you may cause your shares to be voted by returning a signed proxy card, or you may vote in person at the special meeting. Additionally, you may submit electronically over the Internet or by phone a proxy authorizing the voting of your shares by following the instructions on your proxy card. You must have the enclosed proxy card available, and follow the instructions on the proxy card, in order to submit a proxy electronically over the Internet or by telephone. Based on your proxy cards or Internet and telephone proxies, the proxy holders will vote your shares according to your directions.

If you plan to attend the special meeting and wish to vote in person, you will be given a ballot at the meeting. If your shares are registered in your name, you are encouraged to vote by proxy even if you plan to attend the special meeting in person. If you attend the special meeting and vote in person, your vote by ballot will revoke any proxy previously submitted.

Voting instructions are included on your proxy card. All shares represented by properly executed proxies received in time for the special meeting will be voted at the special meeting in accordance with the instructions of the shareholder. Properly executed proxies that do not contain voting instructions will be voted (i) “FOR” the merger proposal, (ii) “FOR” the merger-related compensation proposal and (iii) “FOR” the adjournment proposal. No proxy that is specifically marked against the merger proposal will be voted in favor of the merger-related compensation, unless it is specifically marked “FOR” the approval of such proposal.

If your shares are held in “street name” through a broker, bank or other nominee, you may vote through your broker, bank or other nominee by completing and returning the voting form provided by your broker, bank or other nominee, or by the Internet or telephone through your broker, bank or other nominee if such a service is provided. To vote via the Internet or telephone through your broker, bank or other nominee, you should follow the instructions on the voting form provided by your broker, bank or other nominee. Under applicable stock exchange rules, brokers, banks or other nominees have the discretion to vote your shares on routine matters if you fail to instruct your broker, bank or other nominee on how to vote your shares with respect to such matters. Proposals 1, 2 and 3 in this proxy statement arenon-routine matters, and brokers, banks and other nominees therefore cannot vote on these proposals without your instructions. If you do not return your broker’s, bank’s or other nominee’s voting form, do not vote via the Internet or telephone through your broker, bank or other nominee, if applicable, or do not attend the special meeting and vote in person with a proxy from your broker, bank or other nominee, such actions will have the same effect as if you voted “AGAINST” the merger proposal but will not have any effect on the adjournment proposal or the merger-related compensation proposal.

Revocability of Proxies

If you are a shareholder of record, you may change your vote or revoke your proxy at any time before it is voted at the special meeting by:

Please note that to be effective, your new proxy card, Internet or telephonic voting instructions or written notice of revocation must be received by our Secretary prior to the special meeting and, in the case of Internet or telephonic voting instructions, must be received before 11:59 p.m., [●] timePacific Time on [●], 2018.January 16, 2019. If you have submitted a proxy, your appearance at the special meeting, in the absence of voting in person or submitting an additional proxy or revocation, will not have the effect of revoking your prior proxy.

If you hold your shares of ESL common stock in “street name,” you should contact your broker, bank or other nominee for instructions regarding how to change your vote. You may also vote in person at the special meeting if you obtain a valid proxy from your broker, bank or other nominee. Any adjournment of the special meeting for the purpose of soliciting additional proxies will allow ESL shareholders who have already sent in their proxies to revoke them at any time prior to their use at the special meeting, as adjourned.

Board of Directors’ Recommendation

The Board of Directors, after considering various factors described under the section entitled “Proposal 1: Adoption of the Merger Agreement—The Merger—Recommendation of Our Board of Directors and Reasons for the Merger” beginning on page 40, unanimously (i) determined that it is in the best interests of ESL and its shareholders, and declared it advisable, for ESL to enter into the merger agreement, (ii) approved the execution, delivery and performance by ESL of the merger agreement and the consummation of the merger and the other transactions contemplated by the merger agreement, (iii) directed that the adoption of the merger agreement be submitted to a vote of ESL’s shareholders at a meeting of its shareholders and (iv) resolved to recommend that ESL’s shareholders approve the adoption of the merger agreement and the transactions contemplated therein, including the merger.

The Board of Directors unanimously recommends that you vote (i) “FOR” the merger proposal, (ii) “FOR” the merger-related compensation proposal and (iii) “FOR” the adjournment proposal.

Tabulation of Votes

All votes will be tabulated by a representative of Computershare, who will act as the inspector of election appointed for the special meeting and will separately tabulate affirmative and negative votes, abstentions and brokernon-votes.

Solicitation of Proxies

The expense of soliciting proxies in the enclosed form will be borne by ESL. We have retained MacKenzie Partners, Inc., a proxy solicitation firm, to solicit proxies in connection with the special meeting at a cost of approximately $20,000 plus reasonable expenses. ESL will indemnify MacKenzie Partners, Inc. for certain losses arising out of its proxy solicitation services. In addition, we may reimburse brokers, banks and other custodians, nominees and fiduciaries representing beneficial owners of shares for their expenses in forwarding soliciting

materials to such beneficial owners. Proxies may also be solicited by some of our directors, officers and employees, personally or by telephone, facsimile or other means of communication. No additional compensation will be paid for such services.

Anticipated Date of Completion of the Merger

We currently expect to complete the merger during the secondfirst half of calendar year 2019. However, the exact timing of completion of the merger cannot be predicted because the completion of the merger is subject to certain closing conditions, many of which are outside of ESL’s control, including the adoption of the merger agreement by our shareholders and the receipt of regulatory approvals.

Attending the Special Meeting

Only ESL shareholders of record on the record date, or their duly appointed proxies, and “street name” holders (whose shares are held through a broker, bank or other nominee) who provide evidence of their beneficial ownership on the record date for the special meeting, such as a copy of your most recent account statement or similar evidence of ownership of ESL common stock as of the record date for the special meeting, are entitled to attend the special meeting in person.

All ESL shareholders should also bring photo identification, such as a driver’s license or passport. No cameras, recording equipment, electronic devices, large bags, briefcases or packages will be permitted in the special meeting.

Even if you plan to attend the special meeting in person, we encourage you to complete, sign, date and return the enclosed proxy card or vote electronically over the Internet or via telephone to ensure that your shares will be represented at the special meeting. If you attend the special meeting and vote in person, your vote by ballot will revoke any proxy previously submitted. If you hold your shares in “street name,” because you are not the shareholder of record, you may not vote your shares in person at the special meeting unless you request and obtain a valid proxy from your broker, bank or other nominee.

Assistance

If you need assistance in completing your proxy card or have questions regarding ESL’s special meeting, please contact MacKenzie Partners, Inc. by email at proxy@mackenziepartners.com or by telephone. Shareholders may call toll-free at (800)322-2885 and banks and brokers may call collect at (212)929-5500.

Rights of Shareholders Who Seek Appraisal

If the merger is adopted by ESL shareholders, ESL shareholders who do not vote in favor of the adoption of the merger agreement, who continuously hold such shares through the effective time of the merger, who properly exercise and perfect appraisal of their shares and who meet certain other conditions and statutory requirements described herein will be entitled to appraisal rights in connection with the merger under Section 262 of the DGCL. This means that holders of ESL common stock are entitled to have their shares appraised by the Court of Chancery of the State of Delaware and, in lieu of the $122.50per-share merger consideration, to receive payment in cash of the “fair value” of the shares of ESL common stock, exclusive of any elements of value arising from the accomplishment or expectation of the merger, together with interest to be paid upon the amount determined to be fair value, if any, as determined by the court (subject, in the case of interest payments, to any voluntary cash payments made by ESL pursuant to subsection (h) of Section 262 of the DGCL), so long as they comply with the procedures established by Section 262 of the DGCL.

Shareholders considering seeking appraisal should be aware that the fair value of their shares as determined pursuant to Section 262 of the DGCL could be more than, the same as or less than the value of the consideration they would receive pursuant to the merger if they did not seek appraisal of their shares.

To exercise your appraisal rights, you must (1) not vote in favor of the merger proposal, (2) continuously be the record holder of such shares through the effective time of the merger and (3) otherwise follow the procedures set forth in Section 262 of the DGCL. Your failure to follow the procedures specified under the DGCL will result in the loss of your appraisal rights. The DGCL requirements for exercising appraisal rights are described in further detail in this proxy statement, and the relevant section of the DGCL regarding appraisal rights is reproduced and attached as Annex C to this proxy statement. If you hold your shares of ESL common stock through a broker, bank or other nominee and you wish to exercise appraisal rights, you should consult with your broker, bank or other nominee to determine the appropriate procedures for the making of a demand for appraisal by such broker, bank or other nominee.

ANY COMPANY SHAREHOLDER WHO WISHES TO EXERCISE APPRAISAL RIGHTS OR WHO WISHES TO PRESERVE HIS, HER OR ITS RIGHT TO DO SO SHOULD REVIEW ANNEX C CAREFULLY AND CONSULT HIS, HER OR ITS LEGAL ADVISOR, SINCE FAILURE TO TIMELY AND FULLY COMPLY WITH THE PROCEDURES SET FORTH THEREIN WILL RESULT IN THE LOSS OF SUCH RIGHTS.

PARTIES INVOLVED IN THE MERGER

Esterline Technologies Corporation

Esterline Technologies Corporation is a leading specialized manufacturing company principally serving aerospace and defense customers. We are technologically focused, and design, manufacture and market highly engineered products and systems for application within the industries we serve. ESL operates in three segments structured around our technical capabilities: Avionics & Controls, Sensors & Systems, and Advanced Materials. Our Avionics & Controls business segment produces avionics systems, control and communication systems, and human-machine interface products and technologies. Our Sensors & Systems business segment produces power distribution products and systems, connection technologies and advanced sensors. Our Advanced Materials business segment produces engineered materials and defense technologies.

ESL’s principal executive offices are located at 500 108^th Avenue N.E., Bellevue, Washington 98004, and its telephone number is (425)453-9400.

ESL was formed in 1967 and is organized in the State of Delaware. ESL’s common stock, par value $0.20 per share, which we refer to as ESL common stock or our common stock, is currently listed on the New York Stock Exchange, which we refer to as the NYSE, under the symbol “ESL.”

Additional information about ESL and its subsidiaries is included in documents incorporated by reference in this proxy statement (see “Where You Can Find More Information” beginning on page 101)102) and on its website: www.esterline.com. The information provided or accessible through ESL’s website is not part of, or incorporated by reference in, this proxy statement.

TransDigm Group Incorporated

Through its wholly-owned subsidiaries, TransDigm Group Incorporated is a leading global designer, producer and supplier of highly engineered aircraft components for use on nearly all commercial and military aircraft in service today. Major product offerings, substantially all of which are ultimately provided toend-users in the aerospace industry, include mechanical/electro-mechanical actuators and controls, ignition systems and engine technology, specialized pumps and valves, power conditioning devices, specialized AC/DC electric motors and generators, NiCad batteries and chargers, engineered latching and locking devices, rods and locking devices, engineered connectors and elastomers, cockpit security components and systems, specialized cockpit displays, aircraft audio systems, specialized lavatory components, seatbelts and safety restraints, engineered interior surfaces and related components, lighting and control technology, military personnel parachutes, high performance hoists, winches and lifting devices, and cargo loading, handling and delivery systems.

TransDigm’s principal executive offices are located at 1301 East 9th Street, Suite 3000, Cleveland, Ohio 44114, and its telephone number is (216)706-2960.

TransDigm is incorporated in the State of Delaware. TransDigm’s common stock is currently listed on the NYSE under the symbol “TDG.”

Additional information about TransDigm and its subsidiaries is included on its website: www.transdigm.com. The information provided or accessible through TransDigm’s website is not part of, or incorporated by reference in, this proxy statement.

Thunderbird Merger Sub Inc.

Thunderbird Merger Sub Inc. is incorporated in the State of Delaware and is a wholly owned subsidiary of TransDigm that was formed solely for the purpose of entering into the merger agreement and consummating the transactions contemplated by the merger agreement. Merger Sub’s principal executive offices are located at 1301 East 9th Street, Suite 3000, Cleveland, Ohio 44114, and its telephone number is (216)706-2960. Upon completion of the merger, Merger Sub will cease to exist.

PROPOSAL 1: ADOPTION OF THE MERGER AGREEMENT

THE MERGER

This discussion of the merger is qualified in its entirety by reference to the merger agreement, which is attached to this proxy statement as Annex A and incorporated into this proxy statement by reference. You should read the entire merger agreement carefully as it is the legal document that governs the merger.

Certain Effects of the Merger on ESL

Upon the terms and subject to the conditions of the merger agreement, Merger Sub will merge with and into ESL, with ESL continuing as the surviving corporation in the merger and as a wholly owned subsidiary of TransDigm. ESL expects tode-list its common stock from the NYSE andde-register its common stock under the Exchange Act as promptly as practicable following the effective time of the merger. Thereafter, ESL would no longer be a publicly traded company. If the merger is completed, you will not own any shares of the capital stock of the surviving corporation, and instead will only be entitled to receive the merger consideration, as described under the section entitled “Proposal 1: Adoption of the Merger Agreement—Terms of the Merger Agreement—Merger Consideration” beginning on page 65.66.

The merger will become effective upon the filing of the certificate of merger with the Secretary of State of the State of Delaware, or at such other time as is agreed by ESL and TransDigm and set forth in the certificate of merger.

Effect on ESL if the Merger is Not Completed

If the merger agreement is not adopted by ESL shareholders or if the merger is not completed for any other reason, ESL shareholders will not receive any payment for their shares of ESL common stock. Instead, ESL will remain a public company, ESL’s common stock will continue to be listed and traded on the NYSE and registered under the Exchange Act and ESL will continue to file periodic reports with the SEC.

Furthermore, if the merger is not consummated, and depending on the circumstances that would have caused the merger not to be consummated, it is likely that the price of ESL’s common stock will decline significantly. If that were to occur, it is uncertain when, if ever, the price of ESL’s common stock would return to the price at which it trades as of the date of this proxy statement.

Accordingly, if the merger is not consummated, there can be no assurance as to the effect of these risks and opportunities on the future value of your shares of ESL common stock. If the merger is not consummated, the Board of Directors will continue to evaluate and review ESL’s business operations, properties and capitalization, among other things, make such changes as are deemed appropriate and continue to seek to enhance shareholder value. If the merger agreement is not adopted by ESL’s shareholders or if the merger is not consummated for any other reason, there can be no assurance that any other transaction acceptable to ESL will be offered or that ESL’s business, prospects or results of operation will not be adversely impacted.

In addition, under certain specified circumstances, ESL will be required to pay TransDigm a termination fee upon the termination of the merger agreement, as described under the section entitled “Proposal 1: Adoption of the Merger Agreement—Terms of the Merger Agreement—Termination of the Merger Agreement—Termination Fee” beginning on page 82.83.

Background of the Merger

As a public company, the Company’sEsterline Technologies Corporation’s (the “Company”) Board of Directors (the “Board”) and its executive management regularly evaluate opportunities to provide value to shareholders, including reviews of the Company’s business, strategic goals, industry consolidation trends, input from the Company’s shareholders and potential strategic alternatives.

In December of 2017, the Board retained a strategic advisory firm to provide an assessment of the Company’s strategic alignment with its served markets and a recommendation for how to maximize shareholder value, including an analysis of the Company’s potential strategic alternatives. In February of 2018, the Board expanded the strategic advisory firm’s scope of work to include supporting the Company’s management team in developing a strategic plan for the Company, including a focus on organic growth, possible future acquisitions and potential portfolio divestitures and restructurings. Between January and April of 2018, the Board reviewed and discussed matters related to the strategic advisory firm’s analysis.

Also in fiscal year 2017, the Company explored strategic options associated with its Kirkhill business, which resulted in the sale of the assets and certain liabilities of the Kirkhill business to TransDigm Group Incorporated (“TransDigm”) on March 15, 2018.

On March 26, 2018, during an informal dinner meeting, a member of Party A’s executive management discussed with a member of the Company’s executive management that Party A could have a potential interest in exploring strategic alternatives that might exist between Party A and the Company in the future.

On March 30, 2018, a representative of the Company contacted a representative of its historic financial advisor, Goldman Sachs & Co. LLC (“Goldman Sachs”), seeking potential assistance from Goldman Sachs in performing an analysis of the Company’s strategic alternatives.

On April 20, 2018, the Board held a meeting at which it discussed corporate strategy issues, including a discussion regarding the analysis performed by the strategic advisory firm, which included, among other things, a discussion around the Company’s ability to create value for its shareholders by remaining an independent public company and focusing on management’s 2018 strategic plan,re-shaping the Company’s portfolio and growing the remaining assets through strategic acquisitions, or pursuing a merger or sale of the Company. Following discussion, the Board decided to invite a representative of Goldman Sachs to assist with a review of strategic alternatives at the Board’s next meeting. The Board also discussed hiring a financial advisor, in addition to Goldman Sachs, to advise the Board in connection with the Company’s review of strategic alternatives, and instructed certain representatives of the Board to interview candidates.

Between April 20, 2018 and April 30, 2018, representatives of the Board interviewed Evercore Group L.L.C. (“Evercore”) and another nationally recognized investment banking firm with a view toward potentially retaining a financial advisor in addition to Goldman Sachs, to advise the Board in connection with the Company’s review of strategic alternatives. After discussion, the Board decided to engage Evercore to act as the Board’s financial advisor.

On May 12, 2018, a representative of TransDigm contacted a representative of Goldman Sachs on an unsolicited basis to discuss TransDigm’s interest in potentially acquiring the Company.

On May 15, 2018, the Board entered into an engagement agreement with Evercore to represent the Board as its financial advisor in connection with a possible sale of the Company.

On May 15, 2018, the Board held a meeting attended by a representative of Evercore and a representative of Skadden, Arps, Slate, Meagher & Flom LLP (“Skadden”), the Company’s outside legal advisor. During such meeting, a representative of Skadden reviewed with the Board its fiduciary duties in connection with the Board’s review of the Company’s strategic alternatives. Next, a representative of Evercore provided an overview of Evercore’s views on the strategic alternatives available to the Company, including Evercore’s views on a draft of the preliminary financial analyses of the strategic alternatives available to the Company that Goldman Sachs had prepared to review with the Board the next day. The Board engaged in discussion regarding the presentation and asked questions concerning the different alternatives, timing and process, potential counterparties, and valuation issues. Additionally, members of executive management reviewed with the Board the Company’s 2018 strategic plan, which included certain financial forecasts relating to the Company (see the section of this proxy statement entitled “Proposal 1: Adoption of the Merger Agreement—The Merger—Financial Forecasts”).

On May 16, 2018, the Board held a strategic review meeting at which representatives of Goldman Sachs, Evercore, Skadden and certain members of the Company’s executive management were present. At the meeting, representatives of Goldman Sachs reviewed its preliminary financial analyses of the Company and the strategic alternatives available to the Company, including standalone organic growth, portfolio optimization, portfolio optimization along with acquisition or recapitalization strategies, the sale of the Company as a whole, the sale of the Company in parts or a merger of equals. Representatives of Goldman Sachs reviewed with the Board the unsolicited contact from TransDigm. The Board engaged in discussion and asked questions regarding the preliminary financial analyses and strategic alternatives and the Board, with input from Evercore and representatives of Goldman Sachs, engaged in a discussion regarding the Board’s view that it was a favorable time to explore a potential sale of the Company. Following such discussion, the Board directed the representatives of Goldman Sachs, Evercore and Skadden to work with Company executive management to prepare a process to seek indications of interest from third parties and to report back to the Board with a proposed course of action for its consideration.

On June 6, 2018, the Board held a meeting at which representatives of Goldman Sachs, Evercore, Skadden and certain members of the Company’s executive management were present. Members of executive management reviewed with the Board certain proposed updates to the Company’s 2018 strategic plan, which included certain financial forecasts relating to the Company (see the section of this proxy statement entitled “Proposal 1: Adoption of the Merger Agreement—The Merger—Financial Forecasts”). The Board then discussed with members of executive management and representatives of Goldman Sachs and Evercore the 2018 strategic plan in the context of a process to seek indications of interest from third parties. Following such discussion, representatives of Goldman Sachs updated the Board regarding preparations for a process to seek indications of interest from third parties. The Board also discussed the May 12, 2018 communication received from TransDigm. Following discussion, the Board directed representatives of Goldman Sachs to respond to TransDigm and to invite TransDigm to submit a written indication of interest based on public information.

On June 12, 2018, a representative of Goldman Sachs contacted a representative of TransDigm and conveyed the Board’s response.

On June 14, 2018, a representative of Goldman Sachs received a written indication of interest from TransDigm indicating TransDigm’s interest in acquiring the Company at a price of $94.50 per share in cash. Following receipt, the written indication of interest was distributed to the Board.

On June 19, 2018, the Board held a meeting at which representatives of Goldman Sachs, Evercore, Skadden and certain members of the Company’s executive management were present. Representatives of Goldman Sachs reviewed with the Board the key terms of TransDigm’s written indication of interest as well as Goldman Sachs’ preliminary financial analyses of the Company and TransDigm’s indication of interest. The Board discussed TransDigm’s proposed price per share relative to the price per share projected in the Company’s 2018 strategic plan. The Board also discussed the strategic merits of pursuing a possible transaction with TransDigm compared with certain other potential third parties. Following such discussion, the Board determined that the proposed price per share in TransDigm’s initial indication of interest was too low to proceed in a process to evaluate a transaction solely with TransDigm at the proposed price at such time without a further analysis of the other strategic alternatives that the Company might have. The Board then discussed the process and timing for evaluating strategic alternatives, including a potential sale of the Company, that might exist with other third parties. After further discussion, the Board directed representatives of Goldman Sachs to respond to TransDigm that TransDigm’s proposed price per share was too low to merit proceeding with a transaction between the parties at such time and to give TransDigm an opportunity to increase its price per share. The Board and its advisors then discussed the process and timing for seeking indications of interest from other third parties, and following discussion, the Board directed representatives of Goldman Sachs to contact certain additional specified strategic third parties, including Party A, to help explore whether there was other third party interest in a transaction involving the Company. Next, members of executive management reviewed with the Board the final 2018 strategic plan, which included certain financial forecasts relating to the Company, a copy of which had been provided to the Board prior to the meeting (see the section of this proxy statement entitled “Proposal 1: Adoption

of the Merger Agreement—The Merger—Financial Forecasts”). Following discussion, the Board approved the 2018 strategic plan.

On June 19, 2018, at the direction of the Board, representatives of Goldman Sachs conveyed the Board’s response to TransDigm.

On June 20, 2018, representatives of Goldman Sachs spoke to representatives of TransDigm and further explained the Board’s position, including that TransDigm would need to increase its proposed price per share for the Company in order for the Board to consider proceeding further with TransDigm at such time.

On June 21, 2018, the Company entered into a formal engagement agreement with Goldman Sachs to represent the Company as its financial advisor in connection with a possible sale of the Company.

On June 21, 2018, the Chief Executive Officer of TransDigm contacted the Chief Executive Officer of the Company to explain that TransDigm was submitting a request for additional information that it believed would assist it in increasing its initial proposed price per share for the Company. On June 22, 2018, TransDigm sent a letter to representatives of Goldman Sachs describing the additional requested information.

On June 22, 2018, at the direction of the Board, representatives of Goldman Sachs contacted representatives of Party A, in response to Party A’s previous approach to the Company regarding its interest in a potential transaction involving the Company, and requested that Party A submit a letter to express its interest in a potential transaction involving the Company.

On June 26, 2018, representatives of Goldman Sachs received a written indication of interest from Party A expressing Party A’s interest in a potential acquisition of the Company. Party A did not indicate a proposed purchase price, and it requested additional diligence information to assist it in providing an indicative valuation of the Company. Following receipt, the written indication of interest was distributed to the Board.

On June 28, 2018, the Board held a meeting at which representatives of Goldman Sachs, Evercore, Skadden and certain members of the Company’s executive management were present. Representatives of Goldman Sachs updated the Board on discussions with TransDigm and Party A, and noted that, following discussions, TransDigm had declined to raise its initial proposed price per share and Party A had declined to state a specific price per share, in each case, due to the desire to perform due diligence and obtain further Company information to validate a price. Following discussion, the Board determined that, in its view, there was sufficient potential third party interest in the Company to continue with a process. A representative of Goldman Sachs then updated the Board regarding potential next steps, including a timeline and process to approach other potential strategic and financial third parties to solicit indications of interest in a possible transaction involving the Company. The Board, with input from Company executive management and representatives of Goldman Sachs and Evercore, identified a list of potential strategic and financial third parties it believed could be interested in a possible acquisition of some or all of the Company. The Board also discussed certain talking points that representatives of Goldman Sachs should direct at such parties. Following further discussion, the Board directed Company executive management to continue to work with representatives of Goldman Sachs and Skadden on matters related to the process, including preparation of a form ofnon-disclosure agreement (“NDA”) and a communications plan. The Board then directed representatives of Goldman Sachs to proceed with the outreach to the financial and strategic third parties the Board had identified and authorized Goldman Sachs to approach.

Between July 2, 2018 and August 3, 2018, representatives of Goldman Sachs or the Company contacted 21 third parties, including TransDigm and Party A, and the Company entered into 12 NDAs. The NDAs contained a customary standstill provision that included an exception allowing the respective counterparty to make an alternative proposal to the Company in the event the Company entered into a definitive agreement with a third party regarding an acquisition of the Company. Beginning on July 15, 2018, confidential information and supplemental information packages were distributed to 12 third parties in the process through a virtual data room.

Between July 15, 2018 and July 20, 2018, at the direction of the Board, certain members of the Company’s executive management held separate meetings with each of Party A, Party B, Party C and Party D to discuss the strategic merits of a potential transaction. Representatives of Goldman Sachs attended certain of those meetings.

On July 20, 2018, theWall Street Journal published an article speculating that the Company was exploring a potential sale (the “Wall Street Journal Article”).

Between July 24, 2018 and August 16, 2018, at the direction of the Board, certain members of the Company’s executive management participated in diligence discussions with the third parties participating in the process regarding certain accounting, finance and strategic matters. Representatives of Goldman Sachs attended those meetings.

On July 25, 2018, the Board held a meeting at which representatives of Goldman Sachs, Evercore, Skadden and certain members of the Company’s executive management were present. Representatives of Goldman Sachs reviewed for the Board the status of communications with third parties, including an update on the parties that had executed NDAs, and noted that it had received inbound calls following the Wall Street Journal Article that resulted in the addition of 2 parties to the process. A representative of Goldman Sachs also noted that certain third parties had expressed interest in a potential acquisition of parts of the Company, rather than an acquisition of the Company as a whole, and the Board discussed the movement of the Company’s stock price after the Wall Street Journal Article. Following such discussion, representatives of Goldman Sachs and Skadden discussed with the Board the timing and status of other process points, including the population of a virtual data room and the drafting of a merger agreement, and the Board directed executive management to continue to work with representatives of Goldman Sachs and Skadden on the process.

On July 26, 2018, at the direction of the Board, representatives of Goldman Sachs distributed a supplemental information package and a bid process letter to 12 prospective bidders with instructions to, among other things, provide an indication of interest indicating the proposed purchase price in cash for 100% of the Company.

On August 16, 2018, representatives of Goldman Sachs receivednon-binding written indications of interest for 100% of the Company from TransDigm at $100.50 per share in cash, Party A at a bid range of$95-$98 per share in cash, Party E without a bid price, Party C at $100 per share in cash, Party F at $97 per share in cash, Party B at a bid range of $98 – 103 per share in cash and Party G for $96 per share in cash. Representatives of Goldman Sachs also received an indication of interest from Party J viae-mail, which did not include a bid price. Representatives of Goldman Sachs also received a written indication of interest from Party H for the Connection Technologies business at a bid range of $800 – 870 million and for the Sensors & Systems business at a bid range of $1.45 – 1.575 billion.

On August 17, 2018, representatives of Goldman Sachs received anon-binding written indication of interest for 100% of the Company from Party I at a bid range of $100 – 110 per share in cash.

On August 17, 2018, representatives of Party E and representatives of Goldman Sachs discussed that Party E likely would not submit a proposed price per share for the Company at this time.

On August 18, 2018, at the direction of the Board, representatives of Goldman Sachs spoke to representatives of Party A and communicated that Party A would need to increase its bid in order to continue in the process.

On August 19, 2018, Party A submitted a revisednon-binding written indication of interest for 100% of the Company at $104 per share in cash.

On August 20, 2018, the CEO of Party E contacted representatives of Goldman Sachs and indicated that Party E would not submit a proposed price per share for the Company at this time and indicated that Party E likely would not continue in the process due to strategic, synergistic and timing concerns.

On August 20, 2018, the Board held a meeting, also attended by representatives of Goldman Sachs, Evercore, Skadden and certain members of the Company’s executive management, to discuss the initial indications of interest the Company had received (the “Initial Bids”). Representatives of Goldman Sachs reviewed its preliminary financial analyses of the Company and the Initial Bids, and the other key terms

contained in the Initial Bids. After discussing the Initial Bids, the Board determined that it was not in the best interests of the Company to sell only portions of the Company, and directed representatives of Goldman Sachs and members of the Company’s executive management to continuenon-exclusive negotiations with all bidders who had submitted Initial Bids for 100% of the Company with a purchase price at or above $100 per share, and to cease discussions with Party F, Party G and Party H. Representatives of Goldman Sachs discussed the timing and key events of the process going forward, and the Board directed representatives of Goldman Sachs, Skadden and certain members of the Company’s executive management to continue to proceed with the process.

Beginning on August 27, 2018, the virtual data room was expanded and opened to the remaining participants in the process.

During August and September of 2018, certain members of executive management of the Company made separate management presentations to each of TransDigm, Party A, Party C, Party B and Party I and the remaining participants in the process continued due diligence activities regarding the Company. Representatives of Goldman Sachs attended the executive management meetings.

On September 5, 2018, at the direction of the Board, representatives of Goldman Sachs distributed to each of the remaining participants in the process a draft merger agreement.

On September 6, 2018, at the direction of the Board, representatives of Goldman Sachs distributed to each of the remaining participants in the process a final round bid process letter. Among other things, the final round bid process letter instructed participants to include as part of a final round bid package the purchase price, financing plans, intentions for the business, remaining outstanding diligence requests, anticipated regulatory approvals and an estimate of timing to execute a definitive merger agreement, along with a markup of the draft merger agreement.

During the month of September, 2018, representatives of TransDigm, Party A, Party C and Party B conducted site visits to certain Company facilities, and all of the remaining five participants in the process continued due diligence activities regarding the Company.

On September 13, 2018, press reports from Mergermarket reported that the Company was in discussions with certain named parties regarding a potential acquisition of the Company.

On September 27, 2018, representatives of each of TransDigm, Party A, Party C and Party B submitted mark ups of the draft merger agreement to Skadden.

On September 28, 2018, representatives of Party C communicated to representatives of Goldman Sachs that Party C was not currently in a position to offer a purchase price for the Company, based on its view that, among other things, the scope of due diligence it required to be completed could not be completed in a time frame consistent with the Company’s process.

Between September 28, 2018 and October 4, 2018, legal counsel for TransDigm, Party A and Party B participated in discussions with representatives of Skadden regarding the key provisions of the draft merger agreements, including, among other things, discussions around certain of the Company’s representations and warranties and operating covenants, the size of the termination fee, treatment of equity awards, issues regarding the parties’ required efforts to obtain applicable regulatory approvals and provisions related to each party’s financing of the transaction. During such time, representatives of Party B discussed with representatives of Goldman Sachs that if it submitted a final round offer for the Company, it was likely to be within its initial bid range of between $98 – 103 per share in cash.

On October 5, 2018, representatives of Goldman Sachs received final round writtennon-binding offers for 100% of the Company from TransDigm at $114.50 per share in cash and Party A at $110 per share in cash, along

with commitment letters for debt financing for the transaction, and statements that each of the parties had completed due diligence and was willing to execute a definitive merger agreement in an expedient manner (together, the “October 5th Proposals”). Neither offer was subject to a financing condition. Representatives of Party B communicated to representatives of Goldman Sachs that Party B would not be submitting a final round offer for the Company.

On the morning of October 6, 2018, a meeting was held with representatives of Goldman Sachs, Evercore, Skadden, certain members of the Company’s executive management and the Company’s lead independent director. At the meeting, the final offers from each of TransDigm and Party A were discussed, and a representative of Skadden discussed the key issues that it had been negotiating with each of the bidders remaining in the process in each of the draft merger agreements during the course of the prior week. In the case of TransDigm, among other things, its October 5th proposal lowered the termination fee to 3.5% of the equity value of the transaction compared to its initial proposal of 5% of the equity value of the transaction, narrowed the scope of certain of the Company’s representations and warranties and operating covenants, improved its position on certain provisions related to the obligations of the parties to obtain applicable regulatory approvals and improved certain other contractual terms. In the case of Party A, among other things, its October 5th proposal lowered the termination fee to 3% of the equity value of the transaction compared to its initial proposal of 4% of the enterprise value of the transaction, narrowed the scope of certain of the Company’s representations and warranties and operating covenants, improved its position on certain provisions related to the obligations of the parties to obtain applicable regulatory approvals and improved certain other contractual terms. A representative of Skadden further discussed the appropriate range of termination fees for a deal of this nature, and reviewed the key outstanding issues with respect to each party’s draft merger agreement that related to certain of the Company’s representations and warranties, operating covenants and certain other matters. After discussion, the Company’s lead independent director determined that Skadden should return revised versions of the draft merger agreements to each of TransDigm and Party A, in order that the parties could continue to negotiate the key outstanding issues, and each of TransDigm and Party A should be instructed to deliver its “best and final” offer package, both in purchase price and the merger agreement terms, by 5:00 p.m. (Eastern Standard Time) on Monday, October 8, 2018, so that the Board could evaluate each bid package in its entirety at a meeting to be held on Tuesday, October 9, 2018.

On October 6, 2018, representatives of Skadden sent a revised version of the draft merger agreement and corresponding Company disclosure schedules to each of TransDigm and Party A. Representatives of Goldman Sachs conveyed the timing and next steps of the process to each of TransDigm and Party A and instructed them to submit a best and final offer package on October 8, 2018.

Between October 6 and October 8, 2018, representatives of Skadden continued to hold discussions and negotiate the terms of the merger agreements with legal counsel for each of TransDigm and Party A.

On October 8, 2018, the Board held a meeting, also attended by representatives of Goldman Sachs, Evercore, Skadden and certain members of the Company’s executive management. At the meeting, representatives of Goldman Sachs reviewed for the Board the sale process that had been undertaken on behalf of the Company to identify and engage prospective bidders for the Company, including that representatives of Goldman Sachs or the Company had communicated with 21 prospective bidders, the Company had executed 12 NDAs, 10 parties had conducted detailed due diligence, 9non-binding initial indications of interest were submitted, 5 parties participated in executive management presentations, 4 parties attended site visits, 4 parties submitted an initial markup of the draft merger agreement and 2 final bid packages had been submitted. A representative of Goldman Sachs then discussed the October 5th Proposals, and noted the anticipated receipt of best and final proposals later that day. Members of the Board discussed and asked questions about the process. A representative of Goldman Sachs reviewed its preliminary financial analysis of the Company and the merger consideration offered in the October 5th Proposals. Members of the Board discussed and asked questions regarding the financial analysis. A representative of Evercore also reviewed certain considerations related to the October 5th Proposals and answered questions from certain members of the Board. Following such discussion, a

representative of Skadden reviewed with the Board its fiduciary duties in connection with the proposed transaction and presented a summary of the material terms and open points with respect to the draft merger agreements with each of TransDigm and Party A. The Board, among other things, reviewed and discussed the anticipated timing and process required to obtain regulatory approvals based upon the proposals from each of TransDigm and Party A, including the fact that Party A may have certain timing advantages with respect to obtaining such regulatory approvals, and the timing and process to obtain shareholder approval of the transaction with each of TransDigm and Party A. Following further discussion, the Board agreed to meet the next morning to review the best and final proposals from each of TransDigm and Party A.

Later on October 8, 2018, representatives of Goldman Sachs received a writtennon-binding offer for 100% of the Company from TransDigm at $120.50 per share in cash, with merger agreement terms that included no financing contingency, a termination fee equal to 3.5% of the equity value of the transaction, ano-shop provision with a 3 business day matching right and a fiduciary out provision. Representatives of Goldman Sachs also received a writtennon-binding offer for 100% of the Company from Party A at $118 per share in cash, with merger agreement terms that included no financing contingency, a termination fee equal to 3% of the equity value of the transaction, ano-shop provision with a 3 business day matching right and a fiduciary out provision.

On October 9, 2018, the Board held a meeting, also attended by representatives of Goldman Sachs, Evercore, Skadden and certain members of the Company’s executive management to consider TransDigm’s and Party A’s offers and the proposed terms of the 2 draft merger agreements. A representative of Goldman Sachs reviewed with the Board the terms of the 2 offers it had received on October 8, 2018. Thereafter, a representative from Skadden discussed with the Board its fiduciary duties in evaluating the offers, and compared the material terms between each of the merger agreement drafts the Company had received, noting, among other things, that TransDigm had agreed to improve its position with respect to certain provisions related to the obligations of the parties to obtain applicable regulatory approvals and certain other contractual provisions. Following discussion, including discussion with a representative from Evercore, the Board determined that it wished to proceed with a further discussion solely regarding the terms of TransDigm’s offer, which provided the shareholders of the Company with a higher purchase price than the purchase price offered by Party A. Following such discussion, a representative of Skadden reviewed the key terms of the merger agreement with TransDigm (a summary of which had been previously circulated to the Board) including, among other things, the parties’ respective termination rights (including the Company’s right to terminate the merger agreement if the Board, in the exercise of its fiduciary duties, changes its recommendation under the proposed merger agreement to enter into an agreement with respect to a superior proposal), the termination fee, the obligations of the parties to obtain applicable regulatory approvals, the restrictions on the Company’s ability to solicit alternative proposals, the definition of a “material adverse effect” and the applicable closing conditions. Additionally, the Board considered and discussed its reasons for approving the merger and the adoption of the merger agreement, which are set forth in detail in “Proposal 1: Adoption of the Merger Agreement—The Merger—Recommendation of the Board of Directors and Reasons for the Merger.” Next, representatives of Goldman Sachs reviewed its financial analysis of the Company and the $120.50 per share in cash offered by TransDigm and rendered to the Board an oral opinion, to the effect that, based on and subject to the factors and assumptions set forth in the opinion, the $120.50 per share in cash to be paid to the holders (other than TransDigm and its affiliates) of shares of Company common stock was fair, from a financial point of view, to such holders. After discussing the proposed transaction and considering the presentations by Goldman Sachs and Skadden, and its discussion with a representative of Evercore, the Board unanimously (i) determined that the transaction with TransDigm was in the best interests of the Company and the Company’s shareholders, and declared it advisable for the Company to enter into the merger agreement, (ii) approved the execution, delivery and performance by the Company of the merger agreement and the consummation of the merger and the other transactions contemplated by the merger agreement, (iii) directed that the adoption of the merger agreement be submitted to a vote of the Company’s shareholders at a meeting and (iv) resolved to recommend that the Company’s shareholders approve the adoption of the merger agreement and the transactions contemplated therein, including the merger. Following such resolutions, the Board directed representatives of Goldman Sachs and Skadden to contact TransDigm and convey

that the Board had approved the transaction and authorized the Company’s representatives and executive management to finalize the terms of a definitive merger agreement.

Following the Board meeting, representatives of Goldman Sachs contacted representatives of TransDigm and conveyed that the Board had approved moving forward with the transaction according to the terms offered by TransDigm on October 8, 2018, and had authorized the Company’s representatives and executive management to finalize the definitive merger agreement between the parties.

Also following the Board meeting, representatives of Goldman Sachs were contacted by representatives of Party A inquiring about the status of its offer and, at the direction of the Board, the representatives of Goldman Sachs informed the representatives of Party A that they were behind on proposed purchase price and that the Board had decided to proceed with a transaction with another party.

During the course of the day on October 9, 2018, legal counsel for TransDigm and representatives of Skadden further negotiated, and reached resolution on, the remaining key open points of the merger agreement.

In the afternoon of October 9, 2018, representatives of Goldman Sachs received an unsolicited revised best and final offer from Party A increasing its offered purchase price to $120 per share in cash.

Following the receipt of such offer, at the direction of the Board, representatives of Goldman Sachs contacted representatives of Party A to discuss the increased purchase price to $120 per share in cash, and to ask Party A whether the increased purchase price was, in fact, its best and final offer. Representatives of Party A confirmed to representatives of Goldman Sachs that $120 per share in cash was indeed its best and final offer, and that Party A would not be increasing its offered purchase price again to an amount higher than $120 per share in cash.

Following such conversation, at the direction of the Board, with advice from Evercore and Skadden, representatives of Goldman Sachs contacted representatives of TransDigm and communicated that, following the previous conversation between the parties, representatives of Goldman Sachs had received an unsolicited revised offer from another party in the process that increased its offered purchase price and that the revised offer would be submitted to the Board for its consideration. Representatives of Goldman Sachs indicated that if TransDigm could increase its purchase price offered for the Company beyond $120.50, it should do so, in order for the Board to fully evaluate each party’s offer, including, among other things, the purchase price and certain timing and process considerations related to each proposed transaction.

Later in the afternoon of October 9, 2018, representatives of Goldman Sachs received a revised best and final offer from TransDigm increasing its offered purchase price to $122.50 per share in cash.

Early in the evening of October 9, 2018, the Board held a meeting, also attended by representatives of Goldman Sachs, Evercore, Skadden and certain members of the Company’s executive management, to consider TransDigm’s and Party A’s revised offers. At the meeting, representatives of Goldman Sachs reviewed the increased purchase prices offered by TransDigm and Party A and a representative of Skadden confirmed that the material terms of the merger agreements with the parties had not changed, and that it had reached resolution on the key outstanding items of the merger agreement with TransDigm since the previous meeting. The Board discussed the terms of the revised offers, including the increased purchase prices and certain timing and process considerations of a transaction with each of TransDigm and Party A, and asked questions about the communications since the last meeting. Following such discussion, including discussion with a representative of Evercore regarding certain matters with respect to the revised offers, the Board determined that it wished to proceed with a confirmation of its approval of a transaction with TransDigm at the increased offered purchase price, because, among other things, it provided the Company’s shareholders with a higher purchase price than the purchase price offered by Party A. Following such discussion, representatives of Goldman Sachs reviewed with the Board its financial analysis of the Company and the $122.50 per share in cash offered by TransDigm, and

rendered to the Board an oral opinion, which was subsequently confirmed in writing, to the effect that, as of October 9, 2018, and based on and subject to the factors and assumptions set forth in Goldman Sachs’ written opinion, the $122.50 per share in cash to be paid to the holders (other than TransDigm and its affiliates) of shares of Company common stock was fair, from a financial point of view, to such holders. After discussing the proposed transaction and considering the presentations by Goldman Sachs and Skadden, and the discussion with a representative of Evercore, the Board unanimously (i) determined that the transaction with TransDigm was in the best interests of the Company and the Company’s shareholders, and declared it advisable for the Company to enter into the merger agreement, (ii) approved the execution, delivery and performance by the Company of the merger agreement and the consummation of the merger and the other transactions contemplated by the merger agreement, (iii) directed that the adoption of the merger agreement be submitted to a vote of the Company’s shareholders at a meeting and (iv) resolved to recommend that the Company’s shareholders approve the adoption of the merger agreement and the transactions contemplated therein, including the merger. Following such actions, the Board directed representatives of Goldman Sachs and Skadden to contact TransDigm and convey that the Board had approved the transaction at the higher purchase price and to continue to move towards signing a definitive merger agreement and announcing a transaction with TransDigm.

Following the Board meeting, the merger agreement was executed by the Company and TransDigm later in the evening of October 9, 2018.

On October 10, 2018, prior to the opening of trading of the Company’s common stock on the NYSE, the Company and TransDigm issued a joint press release announcing the execution of the merger agreement.

Recommendation of Our Board of Directors and Reasons for the Merger

Recommendation of Our Board of Directors to Adopt the Merger Agreement, thereby Approving the Transactions Contemplated by the Merger Agreement

On October 9, 2018, the Board of Directors, after considering various factors, certain of which are described below, unanimously (i) determined that it is in the best interests of ESL and its shareholders, and declared it advisable, for ESL to enter into the merger agreement, (ii) approved the execution, delivery and performance by ESL of the merger agreement and the consummation of the merger and the other transactions contemplated by the merger agreement, (iii) directed that the adoption of the merger agreement be submitted to a vote of ESL’s shareholders at a meeting of its shareholders and (iv) resolved to recommend that ESL’s shareholders approve the adoption of the merger agreement and the transactions contemplated therein, including the merger.

Reasons for the Merger

In recommending that ESL’s shareholders vote in favor of the merger proposal, the Board of Directors consulted with executive management of ESL and ESL’s outside financial and legal advisors and carefully considered a number of factors that the Board believed supported its decision, including, but not limited to, the following (not necessarily in order of relative importance):

The Board of Directors also considered a number of uncertainties, risks and other factors in its deliberations concerning the merger and the other transactions contemplated by the merger agreement, including, but not limited to, the following (not necessarily in order of relative importance):

After taking into account all of the factors set forth above, as well as others, the Board of Directors concluded that the risks and uncertainties associated with the merger were outweighed by the potential benefits of the merger to ESL’s shareholders.

The Board of Directors unanimously determined that the merger agreement and the consummation of the merger and the other transactions contemplated by the merger agreement were advisable and in the best interests of ESL and its shareholders and approved the merger agreement. Accordingly, the Board of Directors unanimously recommends that ESL’s shareholders vote “FOR” the merger proposal.

The foregoing discussion of factors considered by the Board of Directors is not intended to be exhaustive, but summarizes the material factors considered by the Board of Directors in its consideration of the merger agreement and the merger. In light of the variety of factors considered in connection with their evaluation of the merger agreement and the merger, the Board of Directors did not find it practicable to, and did not, quantify or otherwise assign relative weights to the specific factors considered in reaching their determinations and recommendations. Moreover, each member of the Board of Directors applied his or her own personal business judgment to the process and may have given different weight to different factors. The Board of Directors did not undertake to make any specific determination as to whether any factor, or any particular aspect of any factor, supported or did not support their ultimate determinations. The Board of Directors based their recommendations on the totality of the information presented, including thorough discussions with, and questioning of, ESL’s executive management and ESL’s and the Board of Directors’ outside financial advisors and outside legal counsel. It should be noted that this explanation of the reasoning of the Board of Directors and certain information presented in this section is forward-looking in nature and should be read in light of the factors set forth in “Forward-Looking Statements” beginning on page 22.

Engagement of Evercore Group L.L.C.

On May 15, 2018 the Board entered into an engagement agreement with Evercore to represent the Board as its financial advisor in connection with a possible sale of the Company (see the section of this proxy statement entitled “Proposal 1: Adoption of the Merger Agreement—The Merger—Background of the Merger”). Under the terms of its engagement agreement with the Company, Evercore will receive advisory fees of between $3.25 million and $6.25 million in connection with its engagement. Other than the engagement described in the

preceding sentence, during the two year period ended October 9, 2018, Evercore has not been engaged by Esterline or its affiliates or TransDigm or its affiliates to provide investment banking financial advisory or capital markets services for which Evercore has recognized compensation.

Opinion of ESL’s Financial Advisor

At the meeting at which the Board of Directors voted to approve the proposed merger, Goldman Sachs rendered to the Board of Directors its oral opinion, subsequently confirmed in writing, to the effect that, as of October 9, 2018, and based upon and subject to the factors and assumptions set forth in Goldman Sachs’ written opinion, the $122.50 in cash per share to be paid to the holders (other than TransDigm and its affiliates) of shares of ESL common stock pursuant to the merger agreement was fair from a financial point of view to such holders.

The full text of the written opinion of Goldman Sachs, dated October 9, 2018, which sets forth the assumptions made, procedures followed, matters considered, qualifications and limitations on the review undertaken in connection with the opinion, is attached to this proxy statement as Annex B. Goldman Sachs’ advisory services and opinion were provided for the information and assistance of the Board of Directors in connection with its consideration of the proposed merger and the opinion does not constitute a recommendation as to how any holder of shares of ESL common stock should vote with respect to the proposed merger or any other matter.

In connection with rendering the opinion described above and performing its related financial analyses, Goldman Sachs reviewed, among other things:

Goldman Sachs also held discussions with members of the senior management of ESL regarding their assessment of the past and current business operations, financial condition and future prospects of ESL; reviewed the reported price and trading activity for the shares of ESL common stock; compared certain financial and stock market information for ESL with similar information for certain other companies the securities of which are publicly traded; reviewed the financial terms of certain recent business combinations in the aerospace and defense industry and in other industries; and performed such other studies and analyses, and considered such other factors, as it deemed appropriate.

For purposes of rendering its opinion, Goldman Sachs, with the consent of the Board of Directors, relied upon and assumed the accuracy and completeness of all of the financial, legal, regulatory, tax, accounting and other information provided to, discussed with or reviewed by, Goldman Sachs, without assuming any responsibility for independent verification thereof. In that regard, Goldman Sachs assumed, with the consent of

the Board of Directors, that the Forecasts had been reasonably prepared on a basis reflecting the best currently available estimates and judgments of the management of ESL. Goldman Sachs did not make an independent evaluation or appraisal of the assets and liabilities (including any contingent, derivative or otheroff-balance-sheet assets and liabilities) of ESL or any of its subsidiaries and Goldman Sachs was not furnished with any such evaluation or appraisal. Goldman Sachs assumed that all governmental, regulatory or other consents and approvals necessary for the consummation of the proposed merger would be obtained without any adverse effect on the expected benefits of the proposed merger in any way meaningful to its analysis. Goldman Sachs assumed that the proposed merger would be consummated on the terms set forth in the merger agreement, without the waiver or modification of any term or condition the effect of which would be in any way meaningful to its analysis.

Goldman Sachs’ opinion did not address the underlying business decision of ESL to engage in the proposed merger, or the relative merits of the proposed merger as compared to any strategic alternatives that may have

been available to ESL; nor did it address any legal, regulatory, tax or accounting matters. Goldman Sachs’ opinion addressed only the fairness from a financial point of view to the holders (other than TransDigm and its affiliates) of shares of ESL common stock, as of October 9, 2018, the date of its opinion, of the $122.50 in cash per share to be paid to such holders pursuant to the merger agreement. Goldman Sachs did not express any view on, and its opinion did not address, any other term or aspect of the merger agreement or the proposed merger or any term or aspect of any other agreement or instrument contemplated by the merger agreement or entered into or amended in connection with the proposed merger, including, the fairness of the proposed merger to, or any consideration received in connection therewith by, the holders of any other class of securities, creditors, or other constituencies of ESL; nor as to the fairness of the amount or nature of any compensation to be paid or payable to any of the officers, directors or employees of ESL, or class of such persons, in connection with the proposed merger, whether relative to the $122.50 in cash per share to be paid to the holders (other than TransDigm and its affiliates) of shares of ESL common stock pursuant to the merger agreement or otherwise. Goldman Sachs did not express any opinion as to the impact of the proposed merger on the solvency or viability of ESL or TransDigm or the ability of ESL or TransDigm to pay their respective obligations when they come due. Goldman Sachs’s opinion was necessarily based on economic, monetary, market and other conditions as in effect on, and the information made available to Goldman Sachs as of, the date of its opinion and Goldman Sachs assumed no responsibility for updating, revising or reaffirming its opinion based on circumstances, developments or events occurring after October 9, 2018, the date of its opinion. Goldman Sachs’s advisory services and its opinion were provided for the information and assistance of the Board of Directors in connection with its consideration of the proposed merger and the opinion does not constitute a recommendation as to how any holder of shares of ESL common stock should vote with respect to the proposed merger or any other matter. Goldman Sachs’s opinion was approved by a fairness committee of Goldman Sachs.

Summary of Financial Analyses

The following is a summary of the material financial analyses delivered by Goldman Sachs to the Board of Directors in connection with the rendering to the Board of Directors of the opinion described above. The following summary, however, does not purport to be a complete description of the financial analyses performed by Goldman Sachs, nor does the order of analyses described represent relative importance or weight given to those analyses by Goldman Sachs. Some of the summaries of the financial analyses include information presented in tabular format. The tables must be read together with the full text of each summary and are alone not a complete description of Goldman Sachs’ financial analyses. Except as otherwise noted, the following quantitative information, to the extent that it is based on market data, is based on market data as it existed on or before October 8, 2018, the last trading day before Goldman Sachs rendered its opinion to the Board of Directors, and is not necessarily indicative of current market conditions.

Historical Stock Trading Analysis. Goldman Sachs analyzed the $122.50 in cash per share to be paid to the holders (other than TransDigm and its affiliates) of shares of ESL common stock pursuant to the merger agreement in relation to the undisturbed closing price per share (which occurred July 19, 2018, the last trading

day prior to market rumors regarding a potential sale of ESL), the closing price per share as of October 8, 2018, the highest price per share for the52-week period ended July 19, 2018 (which occurred July 25, 2017), the volume-weighted average price, which we refer to as VWAP, per share for theone-month period ended July 19, 2018, and the broker median price per share as of October 8, 2018, per IBES consensus. This analysis indicated that the $122.50 in cash per share to be paid to the holders (other than TransDigm and its affiliates) of shares of ESL common stock pursuant to the merger agreement represented:

Illustrative Present Value of Future Share Price Analyses

Goldman Sachs performed an analysis to derive a range of illustrative present values per share of ESL common stock as of September 28, 2018, based on theoretical future prices calculated by Goldman Sachs for the shares of ESL common stock.

Using the Forecasts, Goldman Sachs derived a range of theoretical future enterprise values for ESL as of September 30 of each of calendar years 2019 through 2022, by applying a range of illustrative multiples of enterprise value to EBITDA for the next12-month period, which we refer to as “NTM EBITDA” in this proxy statement, of 8.0x to 10.0x to an estimate of ESL’s NTM EBITDA for the following year, as reflected in the Forecasts. The range of illustrative multiples of enterprise value to NTM EBITDA of 8.0x to 10.0x applied by Goldman Sachs as described above were derived by Goldman Sachs utilizing its professional judgment and experience, taking into account average implied multiples of enterprise value to NTM EBITDA for ESL over various periods ended July 19, 2018.

Goldman Sachs then derived a range of theoretical future values per share of ESL common stock as of September 30, 2019, 2020, 2021 and 2022 by subtracting the estimated net debt (defined for this purpose as ESL’s debt, capital leases and other financing obligations less cash) and minority interest of ESL as of that date, in each case, as reflected in the Forecasts from the theoretical future enterprise values for ESL described above and dividing the result by the estimated fully-diluted shares of ESL common stock outstanding on a standalone basis as of that date as reflected in the Forecasts. Using a discount rate of 11%, reflecting an estimate of ESL’s cost of equity, Goldman Sachs discounted to present value as of September 28, 2018, the range of theoretical future values per share of ESL common stock it derived as of September 30 of each of calendar years 2019 through 2022. Goldman Sachs derived the discount rate of 11% that it used by application of the capital asset pricing model (“CAPM”), which requires certain company-specific inputs, including a beta for ESL, as well as certain financial metrics for the United States financial markets generally. These calculations yielded a range of illustrative present values per share of ESL common stock as of September 28, 2018 of $81 to $112 (rounded to the nearest $1 per share).

Illustrative Discounted Cash Flow Analyses

Using the Forecasts, Goldman Sachs performed an illustrative discounted cash flow analysis of Esterline. Using amid-year convention and discount rates ranging from 9.5% to 10.5%, reflecting estimates of ESL’s

weighted average cost of capital, Goldman Sachs discounted to present value as of September 28, 2018 (i) estimates of unlevered free cash flow for ESL for fiscal years 2019 through 2023, as reflected in the Forecasts, and (ii) a range of illustrative terminal values for ESL (of approximately $3.24 billion to $4.37 billion), which were calculated by applying perpetuity growth rates ranging from 2.5% to 3.5%, to a terminal year estimate of the free cash flow to be generated by ESL, as reflected in the Forecasts (which analysis implied exit terminal year EV/ LTM EBITDA multiples ranging from 7.9x to 10.6x). Goldman Sachs derived such discount rates by application of CAPM, which requires certain company-specific inputs, including ESL’s target capital structure weightings, the cost of long-term debt, future applicable marginal cash tax rate and a beta for Esterline, as well as certain financial metrics for the United States financial markets generally. The range of perpetuity growth rates was estimated by Goldman Sachs utilizing its professional judgment and experience, taking into account the Forecasts and market expectations regarding long-term real growth of gross domestic product and inflation. Goldman Sachs then derived ranges of illustrative enterprise values for ESL by adding the ranges of present values it derived above. Goldman Sachs then subtracted the net debt and minority interests as of September 28, 2018, as provided by ESL’s management and

approved for Goldman Sachs’ use by ESL, from the range of illustrative enterprise values it derived for ESL, to derive a range of illustrative equity values for ESL. Goldman Sachs then divided the range of illustrative equity values it derived by the number of fully diluted outstanding shares of ESL, as provided by ESL’s management and approved for Goldman Sachs’ use by ESL, to derive a range of illustrative present values per share of the ESL’s common stock ranging from $89 to $117 (rounded to the nearest $1 per share).

Selected Transactions Analysis

Goldman Sachs analyzed certain publicly available information relating to acquisition transactions announced in the past seven years involving target companies with operations in the aerospace and defense industry.

While none of the target companies in the selected transactions are directly comparable to ESL and none of the selected transactions are directly comparable to the proposed merger, the target companies in the selected transactions are companies with operations that, for the purposes of analysis, may be considered similar in certain respects to ESL’s financial results and market size.

Using publicly available information for each of the selected transactions, Goldman Sachs calculated the implied enterprise value of the applicable target company based on the consideration paid in the applicable transaction, as a multiple of the target company’s EBITDA for the last12-month period ended prior to announcement of the applicable transaction, which we refer to as “LTM EBITDA” in this proxy statement. The results are set forth below.

Based on the results of the foregoing calculations and Goldman Sachs’ analyses of the various selected transactions and its professional judgment and experience, Goldman Sachs applied a reference range of LTM EBITDA multiples of 8.5x to 12.9x to ESL’s EBITDA, as provided in the summary preliminary results for the just-completed fiscal year 2018, as provided by ESL’s management, to derive a range of implied enterprise values for ESL. Goldman Sachs subtracted from this range of implied enterprise values the ESL’s net debt (defined for this purpose as the ESL’s debt, capital leases and other financing obligations less cash) and minority interest as of September 28, 2018, calculated using information provided by ESL’s management, and divided the result by the total number of fully-diluted shares of ESL common stock outstanding as of October 8, 2018, calculated using information provided by ESL’s management, to derive a range of implied values per share of ESL common stock of $78 to $122 (rounded to the nearest $1 per share).

Premia Paid Analysis

Goldman Sachs reviewed and analyzed, using Thomson Reuters data, the premia paid in all cash acquisitions of publicly traded companies in the United States announced during the period from January 1, 2013 through October 8, 2018, in which the target company had an implied enterprise value of between $250 million and $5 billion based on the consideration paid in the applicable transaction. For each year during this period and over certain periods, Goldman Sachs calculated the average premium and, for certain periods referred to below, various median premiums reflected by the respective prices paid in the transactions as compared to the last closing prices of the target companies’ shares prior to the announcement of the transaction. The following shows a summary of the results of the review:

Based on its review of the foregoing data and its professional judgment and experience, Goldman Sachs applied a reference range of illustrative premia of 25% to 35% to the closing price per share of ESL common stock as of July 19, 2018, the last completed undisturbed trading day. This analysis resulted in a range of implied values of $94 to $102 per share of ESL common stock (rounded to the nearest $1 per share).

General

The preparation of a fairness opinion is a complex process and is not necessarily susceptible to partial analysis or summary description. Selecting portions of the analyses or of the summary set forth above, without considering the analyses as a whole, could create an incomplete view of the processes underlying Goldman Sachs’ opinion. In arriving at its fairness determination, Goldman Sachs considered the results of all of its

analyses and did not attribute any particular weight to any factor or analysis considered by it. Rather, Goldman Sachs made its determination as to fairness on the basis of its experience and professional judgment after considering the results of all of its analyses. No company or transaction used in the above analyses as a comparison is directly comparable to ESL or the proposed merger.

Goldman Sachs prepared these analyses for purposes of providing its opinion to the Board of Directors as to the fairness from a financial point of view to the holders (other than TransDigm and its affiliates) of shares of ESL common stock, as of the date of the opinion, of the $122.50 in cash per share to be paid to such holders pursuant to the merger agreement. These analyses do not purport to be appraisals nor do they necessarily reflect the prices at which businesses or securities actually may be sold. Analyses based upon projections of future results are not necessarily indicative of actual future results, which may be significantly more or less favorable

than suggested by these analyses. Because these analyses are inherently subject to uncertainty, being based upon numerous factors or events beyond the control of the parties or their respective advisors, none of ESL, Goldman Sachs or any other person assumes responsibility if future results are materially different from those forecast.

The $122.50 in cash per share to be paid to the holders of ESL common stock pursuant to the merger agreement was determined througharm’s-length negotiations between ESL and TransDigm and was approved by the Board of Directors. Goldman Sachs provided advice to ESL during these negotiations. Goldman Sachs did not, however, recommend any specific amount of consideration to ESL or the Board of Directors or that any specific amount of consideration constituted the only appropriate consideration for the proposed merger.

As described in “Proposal 1: Adoption of the Merger Agreement—The Merger—Recommendation of the Board of Directors and Reasons for the Merger,” Goldman Sachs’ opinion was one of many factors taken into consideration by the Board of Directors in making its determination to approve the merger agreement. The foregoing summary does not purport to be a complete description of the analyses performed by Goldman Sachs in connection with the delivery of its fairness opinion to the Board of Directors and is qualified in its entirety by reference to the written opinion of Goldman Sachs attached as Annex B to this proxy statement.

Goldman Sachs and its affiliates are engaged in advisory, underwriting and financing, principal investing, sales and trading, research, investment management and other financial andnon-financial activities and services for various persons and entities. Goldman Sachs and its affiliates and employees, and funds or other entities they manage or in which they invest or have other economic interests or with which theyco-invest, may at any time purchase, sell, hold or vote long or short positions and investments in securities, derivatives, loans, commodities, currencies, credit default swaps and other financial instruments of ESL, TransDigm, any of their respective affiliates and third parties, or any currency or commodity that may be involved in the proposed merger. Goldman Sachs has acted as financial advisor to ESL in connection with, and has participated in certain of the negotiations leading to, the proposed merger. Goldman Sachs expects to receive fees for its services in connection with the proposed merger, all of which are contingent upon consummation of the proposed merger, and ESL has agreed to reimburse certain of Goldman Sachs’ expenses arising, and indemnify Goldman Sachs against certain liabilities that may arise, out of Goldman Sachs’ engagement. Goldman Sachs has provided certain financial advisory and/or underwriting services to ESL and/or its affiliates from time to time. During the two year period ended October 9, 2018, the Investment Banking Division of Goldman Sachs has not been engaged by Esterline or its affiliates to provide financial advisory or underwriting services for which Goldman Sachs has recognized compensation. Goldman Sachs has provided certain financial advisory and/or underwriting services to TransDigm and its affiliates from time to time for which its Investment Banking Division has received, and may receive, compensation, including having acted as a joint lead agent with respect to a term loan facility (aggregate principal amount $650,000,000) of TransDigm in October 2016; a joint lead arranger with respect to a term loan facility (aggregate principal amount $1,819,000,000) of TransDigm in August 2017; a joint lead arranger with respect to a term loan facility (aggregate principal amount $5,158,000,000) of TransDigm in November 2017; a joint lead arranger with respect to a term loan facility (aggregate principal amount $1,810,000,000) of TransDigm in February 2018; and a joint bookrunner with respect to a term loan facility (aggregate principal amount $500,000,000) of TransDigm in May 2018. During the two year period ended October 9, 2018, Goldman

Sachs has recognized compensation for financial advisory and/or underwriting services provided by its Investment Banking Division to TransDigm and/or its affiliates of approximately $1,000,000. Goldman Sachs may also in the future provide financial advisory and/or underwriting services to ESL, TransDigm or their respective affiliates, for which its Investment Banking Division may receive compensation.

The Board of Directors selected Goldman Sachs as its financial advisor because it is an internationally recognized investment banking firm that has substantial experience in transactions similar to the proposed merger. Pursuant to an engagement letter dated June 21, 2018, ESL engaged Goldman Sachs to act as its financial advisor in connection with the proposed merger. The engagement letter between ESL and Goldman Sachs provides for a transaction fee that is estimated, based on information available as of the date of announcement, at approximately $38 million, all of which is contingent upon consummation of the proposed

merger. In addition, ESL has agreed to reimburse Goldman Sachs for certain of its expenses, including reasonable attorneys’ fees and disbursements, and to indemnify Goldman Sachs and related persons against various liabilities, including certain liabilities under the federal securities laws.

Financial Forecasts

In connection with a possible transaction, certainnon-public, unaudited prospective financial information for fiscal years 2018 through 2023 was provided to the Board of Directors, Goldman Sachs, ESL’s financial advisor, and to certain participants in the sale process, including TransDigm and its advisors. This unaudited prospective financial information is referred to as the Forecasts.

Although we periodically may issue limited guidance regarding financial performance for the current fiscal year, with the exception of information provided in conjunction with ESL’s investor day on June 19, 2014, ESL does not normally publicly disclose long-term projections as to future revenue, earnings or other results due to, among other reasons, the uncertainty, unpredictability and subjectivity of the underlying assumptions and estimates, including the difficulty of predicting economic and market conditions. The Forecasts were not prepared with a view to public disclosure and are included in this proxy statement only because such information was made available as described above. The Forecasts were not prepared with a view to compliance with generally accepted accounting principles as applied in the United States, which we refer to as GAAP, the published guidelines of the SEC regarding projections and forward-looking statements or the guidelines established by the American Institute of Certified Public Accountants for preparation and presentation of prospective financial information. The prospective financial information included in this proxy statement has been prepared by, and is the responsibility of, ESL’s management. Ernst & Young LLP has neither audited, reviewed, examined, compiled nor applied agreed-upon procedures with respect to the accompanying prospective financial information and, accordingly, Ernst & Young LLP does not express an opinion or any other form of assurance with respect thereto. Any Ernst & Young LLP reports that are incorporated by reference into this proxy statement relate to ESL’s historical financial information. It does not extend to the prospective financial information and should not be read to do so.

As part of ESL’s customary annual processes, a five-year plan is presented to the Board of Directors for review and approval. This five-year plan is not ordinarily disclosed publicly and its primary uses are to drive ESL’s strategic planning and to serve as the basis for ESL’s long-term incentive plan. ESL management reviewed its proposed fiscal years 2018 through 2023 five-year plan at a Board of Directors meeting on May 15, 2018, and the Board of Directors approved the final plan at a subsequent meeting on June 19, 2018. This approved plan was used as the basis for the Forecasts that were provided to the Board of Directors, Goldman Sachs, ESL’s financial advisor, and to certain participants in the sale process, including TransDigm and its advisors. For fiscal year 2018, the Forecasts were prepared on an adjusted pro forma basis, and excluded (a) any financial impact, including revenue, gross profit, EBIT, and all expense, including the loss on sale, of the Kirkhill business, the assets of which were sold late in the second fiscal quarter to TransDigm, (b) the impact of the $48.6 millionone-time tax expense resulting from the U.S. Tax Cuts and Jobs Act of 2017, which was recorded in ESL’s fiscal first quarter, (c) expenses associated with a temporary shutdown at one of ESL’s locations in

ESL’s fiscal fourth quarter, and (d) any fees or expenses of outside advisors, whether financial, legal, or strategic, related to this sale process.

Although a summary of the Forecasts is presented with numerical specificity, it reflects numerous assumptions and estimates as to future events made by our management, including with respect to general market, economic, and political conditions, the award to ESL of future business, and ESL’s operational performance, that our management believed were reasonable at the time the Forecasts were prepared, taking into account the relevant information available to management at the time. However, this information is not fact and should not be relied upon as necessarily indicative of actual future results. Important factors that may affect actual results and cause the Forecasts not to be achieved include general economic conditions, accuracy of certain accounting assumptions, changes in actual or projected cash flows, competitive pressures, changes in tax

laws and other factors described or referenced under the section entitled “Forward-Looking Statements” beginning on page 22. In addition, the Forecasts do not take into account any circumstances or events occurring after the date that they were prepared and do not give effect to the merger. As a result, there can be no assurance that the Forecasts will or would be realized, and actual results may be materially better or worse than those contained in the Forecasts.

The Forecasts are not a reliable indication of future results, and ESL and its management team and advisors do not endorse the Forecasts as such, and they do not make any representation to readers of this document concerning the ultimate performance of ESL or the combined company compared to the Forecasts. ESL is including these projections in this document solely because it was among the financial information made available to the Board of Directors, Goldman Sachs, and TransDigm and its advisors in connection with their evaluation of the merger, and not to influence your decision on how to vote on any proposal.

The Forecasts should be evaluated, if at all, in conjunction with the historical financial statements and other information regarding ESL contained in our public filings with the SEC. Our management reviewed the Forecasts with the Board of Directors, which considered the Forecasts in connection with its evaluation and approval of the merger agreement and the merger. In preparing its financial analyses and opinion summarized under the section entitled “Proposal 1: Adoption of the Merger Agreement—The Merger—Opinion of ESL’s Financial Advisor” beginning on page 43,44, Goldman Sachs relied on the accuracy and completeness of the information provided with respect to the Forecasts and the assurances of our management that it was not aware of any facts or circumstances that would make such information inaccurate or misleading in any material respect.

The Forecasts constitute a forward-looking statement. For information on factors that may cause ESL’s future results to materially vary, see the section entitled “Forward-Looking Statements” beginning on page 22, and information in our consolidated financial statements and notes thereto included in our most recent filings on Form10-K and Amendment No. 1 on Form10-K/A and subsequent periodic and interim report filings (see “Where You Can Find More Information” beginning on page 101)102).

Except to the extent required by applicable federal securities laws, we do not intend, and expressly disclaim any responsibility, to update or otherwise revise the Forecasts to reflect circumstances existing after the date when ESL prepared the Forecasts or to reflect the occurrence of future events or changes in general economic or industry conditions, even in the event that any of the assumptions underlying the Forecasts are shown to be in error.

In light of the foregoing factors and the uncertainties inherent in the Forecasts, shareholders are cautioned not to place undue reliance on the Forecasts.

Certain of the measures included in the Forecasts may be considerednon-GAAP financial measures.Non-GAAP financial measures should not be considered in isolation from, or as a substitute for, financial information presented in compliance with GAAP, andnon-GAAP financial measures as used by ESL may not be comparable to similarly titled amounts used by other companies.

The following table reflects selected metrics reflected in, or generated from, the Forecasts:

In addition, on October 5, 2018, certain estimated preliminary results, also calculated on an adjusted pro forma basis, for the just-completed fiscal year ended September 28, 2018 were shared with the Board of Directors, Goldman Sachs, ESL’s financial advisor, and to certain participants in the sale process, including TransDigm and its advisors, as follows:

Reconciliation of the adjusted pro forma preliminary results for the just-completed fiscal year ended September 28, 2018 to the preliminary results is as shown below:

Also, on October 5, 2018, certain estimated preliminary balance sheet items for the just-completed fiscal year ended September 28, 2018 were shared with the Board of Directors, Goldman Sachs, ESL’s financial advisor, and to certain participants in the sale process, including TransDigm and its advisors, as follows:

Interests of the Directors and Executive Officers of ESL in the Merger

When considering the recommendation of the Board of Directors that you vote to approve the proposal to adopt the merger agreement, you should be aware that our directors and executive officers may have interests in the merger that may be different from, or in addition to, your interests as a shareholder. The Board of Directors was aware of and considered these interests to the extent such interests existed at the time, among other matters, in evaluating and overseeing the negotiation of the merger agreement, in approving the merger agreement and the merger and in recommending that the merger agreement be adopted by the shareholders of ESL. For purposes of each of the ESL plans and agreements described below, the consummation of the merger will constitute a “change in control,” “change of control” or term of similar meaning with respect to ESL.

Arrangements with TransDigm

As of the date of this proxy statement, none of our executive officers has entered into any agreement with TransDigm or any of its affiliates regarding employment with the surviving corporation or one or more of its affiliates.

Treatment of Company Awards

Options. Company Options held by our directors and executive officers will be treated like all other Company Options at the effective time of the merger. At the effective time of the merger, each Company Option granted under a Company Stock Plan that is outstanding immediately prior to the effective time, whether vested or unvested, will be cancelled and converted into the right to receive an amount in cash (without interest and subject to deduction for any required withholding tax) equal to the product obtained by multiplying (i) the amount by which $122.50 exceeds theper-share exercise price of such Company Option, by (ii) the total number of shares of ESL common stock underlying such Company Option, which cash payment will be made within 5 business days following the effective time. If theper-share exercise price of any such Company Option is equal to or greater than $122.50, such Company Option will be cancelled as of the effective time without the payment of any consideration.

Restricted Stock Units. Company RSUs held by our directors and executive officers will be treated like all other Company RSUs at the effective time of the merger. At the effective time of the merger, each award of Company RSUs granted under a Company Stock Plan that is outstanding immediately prior to the effective time, whether vested or unvested, will be cancelled and converted into the right to receive an amount in cash (without interest and subject to deduction for any required withholding tax) equal to the product obtained by multiplying (i) $122.50, by (ii) the total number of shares of ESL common stock underlying such Company RSU, which cash payment will be made within 5 business days following the effective time.

Performance Stock Units. Company PSUs held by our directors and executive officers will be treated like all other Company PSUs at the effective time of the merger. At the effective time of the merger, each award of Company PSUs granted under a Company Stock Plan that is outstanding immediately prior to the effective time, whether vested or unvested (treating for this purpose any performance-based vesting condition to which such Company PSU is subject as having been attained at the “target level” with proration), will be cancelled and converted into the right to receive an amount in cash (without interest and subject to deduction for any required withholding tax) equal to the product obtained by multiplying (i) $122.50, by (ii) the total number of shares of ESL common stock underlying such Company PSU, which cash payment will be made within 5 business days following the effective time.

Shares Held by Directors and Executive Officers. Any shares of ESL common stock held by our directors and executive officers will be treated in the same manner as outstanding shares of ESL common stock held by all other shareholders of ESL entitled to receive the merger consideration.

Merger-Related Payments

The table below sets forth the estimated amounts that each director, named executive officer, and other executive officer of ESL would be eligible to receive (without subtraction of applicable withholding taxes through net settlement or otherwise) with regard to shares of ESL common stock, Company Options, Company RSUs, and Company PSUs, in each case, that are outstandingexpected to be held as of April 1, 2019 (as determined on November 1, 2018,27, 2018), assuming the merger closes on NovemberApril 1, 2018.2019. Depending on when the merger is completed, directors and executive officers may receive a grant of additional equity awards for the 2019 fiscal year (which amounts are not determinable at this time and therefore are not reflected in the table)or determine to sell shares they hold and certain outstanding equity shown in the table below may become vested in accordance with their terms without regard to the merger. Mr. George and Ms. Mason are listed as named executive officers in the table because they appear as named executive officers in ESL’s annual proxy statement for the fiscal year ended September 29, 2017.

Merger Proxy Beneficial Ownership Table

(as of NovemberApril 1, 2018)2019)

For an estimate of the value of the amounts that would be paid or become payable to each of ESL’s named executive officers, assuming, among other things, that the merger waswill be completed on NovemberApril 1, 20182019 and the employment of each named executive officer (other than Mr. George and Ms. Mason whose employment actually terminated prior to November 1, 2018)the date of this proxy statement) was terminated either by ESL without cause or by the named executive officer for good reason immediately thereafter, see the section of this proxy statement entitled “Proposal 2: Advisory Vote on Merger-Related Executive Compensation Arrangements.” The amounts shown under the “Equity” column of the “Quantification of Potential Payments and Benefits to Named Executive Officers in Connection with the Merger” table set forth in Proposal 2 include the aggregate value of the acceleration and payout of all outstanding unvested equity awards held by ESL’s named executive officers if the merger were to occur on NovemberApril 1, 20182019 (which value represents the sum of the amounts shown under the columns “Value of Unvested Company Options,” “Value of Company RSUs” and “Value of Company PSUs” in the Merger Proxy Beneficial Ownership Table above), in addition to certain double-trigger severance payments and benefits that would become due under the terms of each named executive officer’s termination protection agreement with ESL (as reflected in the “Cash,” “Perquisites / Benefits” and “Tax Reimbursement” columns of the “Quantification of Potential Payments and Benefits to Named Executive Officers in Connection with the Merger” table) as applicable.

Executive Officer Termination Protection Agreements

ESL has entered into termination protection agreements with each of its executive officers which include a “double-trigger” severance provision, whereby if the executive officer’s employment is terminated by ESL without “cause” or by the executive officer for “good reason,” in either case, within two years after the day preceding a “change in control” (as those terms are defined in the applicable termination protection agreement), the executive officer will be entitled to receive the following payments and benefits:

In addition, during the two year period commencing on the day preceding the change in control date, the termination protection agreements provide that ESL will maintain the equivalent total value of the compensation paid to the executive officer prior the change in control effective date to include the following:

The termination protection agreements provide that if any payments under those agreements are considered to be “excess parachute payments” under Section 280G of the Code, either alone or together with other payments from ESL, the payments will be reduced so that the payments will not be treated as “excess parachute payments.” However, this payment reduction will only take place if the reduction would provide to the executive officer a greater net,after-tax benefit than he or she would receive if the payments were not subject to the reduction.

ESL is also considering taking certain other actions to mitigate the expected impact of Section 280G of the Code but such actions will not result in an increase in compensation to which the executive officers are already entitled under any existing arrangements.

Employment Offer or Promotion Letters with Executive Officers

Each of Messrs. Benson, Reusser and Ross is a party to an employment offer letter with ESL, and Mr. Yost is a party to a promotion offer letter with ESL, each of which refers to compensation payable pursuant to ESL’s change in control agreement as a corporate officer. These change in control agreements take the form of the

termination protection agreements as described above. Each of Messrs. Nolan and Walther is a party to an employment offer letter with ESL which refers to coverage under the executive officer’s respective termination protection agreement. Except with respect to coverage under the termination protection agreements, none of the employment offer or promotion letters provide for any severance or change in control payments or benefits.

Equity Plans

Pursuant to ESL’s 2013 Equity Incentive Plan, together with the terms of the termination protection agreements (as described above), all Company Options and Company RSUs held by the executive officers do not vest upon certain company transactions if the successor converts, assumes or replaces such awards, unless the executive officer is terminated without cause or resigns with good reason within 24 months following such transaction. If the outstanding Company Options and Company RSUs held by the executive officers are not converted, assumed or replaced by the successor in such transaction, the outstanding awards become fully and immediately vested and exercisable, as applicable.

All Company Options and Company RSUs units held by the executive officers that were granted prior to September 2015 become fully and immediately vested and exercisable immediately prior to certain acquisitions of ESL’s outstanding securities and changes in the composition of the Board of Directors. Company Options and Company RSUs granted to executive officers after September 2015 will not vest automatically upon such events. Company PSUs earned and outstanding as of the date of a company transaction and for which the payout level has been determined are payable in full in accordance with the original payout schedule. Company PSUs for which the payout level has not been determined will be prorated at the target payout level up to and including the date of such transaction.

In the event of the consummation of the merger, at the effective time of the merger, all Company Options, Company RSUs and Company PSUs will be subject to the treatment described under the section entitled “Proposal 1: Adoption of the Merger Agreement—The Merger—Interests of the Directors and Executive Officers of ESL in the Merger—Treatment of Company Awards,” beginning on page 53.

Annual Incentive Plan

Each of ESL’s executive officers participates in ESL’s Annual Incentive Compensation Plan for Corporate Office Participants (which we refer to as the “Company Annual Incentive Plan”). Each executive officer has an individual target award opportunity under the Annual Incentive Plan, expressed as a percentage of annual base salary. The target bonus opportunities for ESL’s executive officers range from 45% to 100% of annual base salary. Based upon achievement of the financial and strategic performance measures that are established by ESL’s compensation committee for any given fiscal year, each executive officer will be eligible to receive an amount of annual incentive compensation for that fiscal year.

As described above, each of ESL’s executive officers is a party to a termination protection agreement. Pursuant to the termination protection agreements, during the two year period after the day preceding a change in control, ESL will maintain the equivalent total value of the compensation paid to each executive officer prior the change in control effective date, which includes, among other things, payment to the executive officer, within 75

days following the end of a fiscal year, of compensation with respect to each such fiscal year ending after the date immediately prior to the change in control date an amount at least equal to his or her target annual incentive compensation. If the executive officer incurs a qualifying termination of employment during the two year period after the day preceding a change in control, the executive officer will be entitled to severance payments and benefits under the termination protection agreement, which includes, among other things, a lump sum payment equal to three times the executive officer’s minimum total compensation, as described above.

Nonqualified Deferred Compensation Plans

DC SERP. All of ESL’s executive officers participate in a nonqualified, unsecured executive supplemental retirement and deferred compensation plan (which we refer to as the “DC SERP”) that allows participants to

defer compensation in excess of certain statutory limits in the ESL tax qualified 401(k) plan (in which ESL’s executive officers also participate) and provides an ESL match on deferred compensation amounts that exceed certain limits in the tax-qualified 401(k) plan that is based on a formula that is substantially the same as that in thetax-qualified 401(k) plan.

Pension SERPs. ESL maintains two nonqualified, unsecured, executive retirement pension plans. The first plan (which we refer to as the “SERP Pre 2005”) was frozen on December 31, 2004, and the second plan (which we refer to as the “SERP 2005+”) became effective on January 1, 2005. Each of the SERP Pre 2005 and SERP 2005+ permits benefits to be earned on compensation that is in excess of certain statutory limits that apply to ESL’stax-qualified pension plan (in which ESL’s executive officers also participate) based on benefit formulas that are similar to the final average pay formula and the cash balance formula in thetax-qualified pension plan. The following executive officers participate in the SERP 2005+: Messrs. Benson, Nolan, Reusser, Ross and Yost. None of ESL’s current executive officers participate in the SERP Pre 2005.

Funding of Executive Nonqualified Deferred Compensation Plans. No later than the day preceding the closing, ESL will contribute to rabbi trusts formed for the DC SERP, funds sufficient to fully satisfy all then outstanding benefit obligations under such plan.

Effect of the Merger Under the Nonqualified Deferred Compensation Plans. At the time of this filing, no amounts payable to any of the participants in ESL’s nonqualified deferred compensation plans will be enhanced or accelerated in connection with the merger. See the compensation tables entitled “Pension Benefits for Fiscal 2017” and “Nonqualified Deferred Compensation Table for Fiscal 2017” and the accompanying narrative disclosure in ESL’s Definitive Proxy Statement for relating to its annual meeting of shareholders held on February 8, 2018 for additional information regarding benefits payable to ESL’s named executive officers under the nonqualified deferred compensation plans.

Fiscal 2019 Equity Grants

Under and subject to the terms of the Merger Agreement, ESL may grant annual equity awards for the 2019 fiscal year to employees, including its directors and executive officers, pursuant to ESL’s customary annual grant cycle for the 2019 fiscal year or in the ordinary course of business consistent with past practice. SuchOn November 14, 2018, the Board granted restricted stock units to ESL’s executive officers. ESL expects to grant the 2019 annual equity awards will be subject to its directors immediately following its annual meeting in February 2019, in accordance with the terms and conditionstiming of ESL’s 2013 Incentive Award Plan and an applicable award agreement evidencingprior annual equity grants to directors. The amount of equity awards to be made to ESL’s directors in respect of the award.2019 fiscal year has not yet been issued, but is expected to be $110,000 in value consistent with the existing director compensation program. Any such equity awards that are outstanding immediately prior to the effective time, whether vested or unvested, will be subject to the treatment described under the section entitled “Proposal 1: Adoption of the Merger Agreement—The Merger—Interests of the Directors and Executive Officers of ESL in the Merger—Treatment of Company Awards,” beginning on page 53. As of the date of this proxy statement, the amount of any additional equity grants to be made to employees, including the directors and executive officers, of ESL in respect of the 2019 fiscal year or otherwise have not yet been determined.

Estimated Severance Payable to Executives

None of ESL’s executive officers are entitled to any severance payments or benefits unless there is both: (1) a change in control; and (2) a termination of employment either by ESL without cause or by the executive officer for good reason, in which case, the executive officer is entitled to severance pursuant to his or her termination protection agreement as described above.

For an estimate of the value of the amounts that would be paid or become payable to each of ESL’s named executive officers, assuming, among other things, that the merger was completed on NovemberApril 1, 20182019 and the employment of each named executive officer (other than Mr. George and Ms. Mason whose employment actually terminated prior to November 1, 2018)the date of this proxy statement) was terminated either by ESL without cause or by the named executive officer for good reason immediately thereafter, see the section of this proxy statement entitled “Proposal 2: Advisory Vote on Merger-Related Executive Compensation Arrangements.”

Sections 280G and 4999 of the Code

None of the executive officers are entitled to anygross-up payments in respect of any excise taxes imposed on “excess parachute payments” under Sections 280G and 4999 of the Code. Rather, if any of the amounts

provided for under the executive officer’s termination protection agreement or otherwise would constitute “parachute payments” within the meaning of Section 280G of the Code and would be subject to the related excise tax imposed under Section 4999 of the Code, the executive officer would receive either the full amount of such payments and benefits or such lesser amount that would result in no portion of the payments and benefits being subject to such excise tax, whichever results in the greaternet-after-tax amount to such executive officer.

Employee Matters

Under the merger agreement, TransDigm is obligated to provide, or to cause to be provided, each employee of ESL and its subsidiaries who is employed as of immediately prior to the effective time and who may continue to be employed following the effective time, including ESL’s executive officers, with certain additional benefits following the closing of the merger. These benefits are further described in the section entitled “Proposal 1: Adoption of the Merger Agreement—Terms of the Merger Agreement—Additional Agreements—Employees and Employee Benefits” beginning on page 76.77.

Insurance and Indemnification of Directors and Officers

Under the merger agreement, TransDigm and the surviving corporation are obligated to provide continued indemnification and directors’ and officers’ liability insurance for a period of six (6) years from the effective time of the merger. These benefits are further described in the section entitled “Proposal 1: Adoption of the Merger Agreement—Terms of the Merger Agreement—Additional Agreements—Directors’ and Officers’ Indemnification Insurance” beginning on page 77.78.

Financing of the Merger and Treatment of Existing Debt

In connection with entering into the merger agreement, TransDigm entered into a commitment letter, dated as of October 9, 2018, with Morgan Stanley Senior Funding, Inc., Credit Suisse Loan Funding LLC and Credit Suisse AG, that provided commitments for a $3.7 billion senior secured term facility subject to customary conditions precedent. TransDigm expects to finance the merger through proceeds from such debt financing and cash on hand. However, the merger is not conditioned on TransDigm’s ability to obtain any financing.

TransDigm will use, and shall cause its affiliates to use, their reasonable best efforts to take, or cause to be taken, all actions, and to do, or cause to be done, all things necessary or advisable to arrange and to obtain the proceeds of the debt financing on terms and conditions no less favorable to TransDigm than those contained in the commitment documents. ESL will use, and shall cause its subsidiaries to use, its and their reasonable best

efforts to cooperate with TransDigm prior to closing, as reasonably requested by TransDigm and at TransDigm’s sole expense, in connection with TransDigm’s arrangement of its debt financing.

The obligations of the lenders to provide TransDigm the debt financing described in the commitment documents are subject to a number of customary conditions precedent, including entry into customary documentation, and the commitments of those lenders to provide TransDigm such debt financing will terminate at 5:00 p.m., New York City time, on October 9, 2019 (which shall be extended to January 9, 2020 if all conditions under the merger agreement are satisfied as of such date other than certain regulatory approvals and foreign investment filings).

All obligations under ESL’s existing credit facility with Wells Fargo Bank, National Association, will be repaid at closing by TransDigm. On or prior to the consummation of the merger and at the written request of TransDigm, ESL will send a notice of redemption in compliance with the indenture governing TA Mfg Limited’s 3.625% senior notes due 2023 and take other actions to redeem such notes, so long as such redemption is conditioned on the consummation of the merger and TransDigm has deposited the funds required to redeem such notes.

Accounting Treatment

TransDigm prepares its financial statements in accordance with accounting principles generally accepted in the United States, which is referred to as GAAP. The merger will be accounted for as an acquisition of ESL by TransDigm under the acquisition method of accounting in accordance with GAAP. TransDigm will be treated as the acquirer for accounting purposes.

U.S. Federal Income Tax Consequences of the Merger

The following is a summary of the U.S. federal income tax consequences of the merger to U.S. holders andnon-U.S. holders (each as defined below) of ESL common stock who hold their stock as a capital asset within the meaning of Section 1221 of the Code. This summary is based on currently existing provisions of the Code, the existing, temporary and proposed U.S. Treasury Department regulations issued under the Code, which we refer to as the Treasury Regulations, and administrative and judicial interpretations thereof, all in effect as of the date of this proxy statement and all of which are subject to change at any time, possibly with retroactive effect, or differing interpretations. This summary is not binding on the Internal Revenue Service, which we refer to as the IRS, or a court and there can be no assurance that the tax consequences described in this summary will not be challenged by the IRS or that they would be sustained by a court if so challenged. No ruling has been or will be sought from the IRS, and no opinion of counsel has been or will be rendered, as to the U.S. federal income tax consequences of the merger.

For purposes of this discussion, the term “U.S. holder” means a beneficial owner of ESL common stock that is for U.S. federal income tax purposes (1) an individual who is a citizen or resident of the United States, (2) a corporation (or other entity treated as a corporation for U.S. federal income tax purposes) created or organized under the laws of the United States, any state thereof, or the District of Columbia, (3) an estate the income of which is includible in gross income for U.S. federal income tax purposes regardless of its source or (4) a trust if (A) a court within the United States is able to exercise primary supervision over the administration of the trust and one or more U.S. persons have the authority to control all substantial decisions of the trust, or (B) the trust has a valid election in effect under applicable Treasury Regulations to be treated as a U.S. person for U.S. federal income tax purposes. A“non-U.S. holder” means a beneficial owner of ESL common stock that is neither a U.S. holder nor a partnership for U.S. federal income tax purposes.

The tax consequences of the merger to shareholders who hold their shares of ESL common stock through a partnership or other flow-through entity will generally depend on the status of the shareholder and the activities of the partnership or other flow-through entity. Partners in a partnership (or other flow-through entity) holding shares of ESL common stock should consult their tax advisors regarding the tax consequences of the merger to them.

This summary is not a complete description of all the U.S. federal income tax consequences of the merger and, in particular, may not address U.S. federal income tax considerations applicable to holders of ESL common stock who are subject to special treatment under U.S. federal income tax law including, for example, partnerships (or an entity or arrangement treated as a partnership for U.S. federal income tax purposes) and partners therein, financial institutions, dealers in securities, insurance companies,tax-exempt entities, mutual funds, real estate investment trusts, personal holding companies, regulated investment companies, securities or currency dealers, traders in securities who elect to use themark-to-market method of accounting,tax-exempt investors, S corporations, holders whose functional currency is not the U.S. dollar,tax-deferred or other retirement accounts, U.S. expatriates, former long-term residents of the United States, holders who acquired ESL common stock pursuant to the exercise of an employee stock option or right or otherwise as compensation, and holders who hold ESL common stock as part of a hedge, straddle, constructive sale, conversion transaction, or other integrated investment. Also, this summary does not address U.S. federal income tax considerations applicable to holders of ESL common stock who exercise appraisal rights under Delaware law. Further, this summary does not address any tax consequences of the merger to U.S. holders of options, shares of restricted stock, restricted share units,

performance stock units or warrants to acquire shares of ESL common stock whose options, shares of restricted stock, restricted share units, performance stock units or warrants are canceled in exchange for cash or other consideration pursuant to the merger. Holders of such options, shares of restricted stock, restricted share units, performance units or warrants should consult their tax advisors regarding the tax consequences of the merger to them. In addition, no information is provided with respect to the tax consequences of the merger under any U.S. federal law other than income tax laws (including, for example the U.S. federal estate, gift, Medicare, and alternative minimum tax laws), or any applicable state, local, or foreign tax laws or any changes (or proposed changes) in applicable tax laws and interpretations thereof. This summary does not address the tax consequences of any transaction other than the merger.

The tax consequences of the merger will depend on your specific situation. You should consult your tax advisor as to the tax consequences of the merger in your particular circumstances, including the applicability and effect of the alternative minimum tax and any state, local,non-U.S. or other tax laws and of changes in those laws.

Tax Consequences to U.S. Holders

The receipt of cash by U.S. holders in exchange for shares of ESL common stock pursuant to the merger will be a taxable transaction for U.S. federal income tax purposes. In general, for U.S. federal income tax purposes, a U.S. holder who receives cash in exchange for shares of ESL common stock pursuant to the merger will recognize capital gain or loss in an amount equal to the difference, if any, between (1) the amount of cash received in the merger and (2) the U.S. holder’s adjusted tax basis in its ESL common stock exchanged therefor. A U.S. holder’s adjusted tax basis will generally equal the price the U.S. holder paid for such shares. If a U.S. holder’s holding period in the shares of ESL common stock surrendered in the merger is greater than one year as of the date of the merger, the gain or loss will be long-term capital gain or loss. Long-term capital gains of certainnon-corporate holders, including individuals, are generally subject to U.S. federal income tax at preferential rates. The deductibility of a capital loss recognized on the exchange is subject to limitations. If a U.S. holder acquired different blocks of ESL common stock at different times or different prices, such U.S. holder must determine its adjusted tax basis and holding period separately with respect to each block of ESL common stock.

Tax Consequences toNon-U.S. Holders

Payments made to anon-U.S. holder in exchange for shares of ESL common stock pursuant to the merger generally will not be subject to U.S. federal income tax unless:

Gain described in the first bullet point above will be subject to tax at generally applicable U.S. federal income tax rates. Any gain described in the first bullet point above of anon-U.S. holder that is a corporation may also be subject to an additional “branch profits tax” at a 30% rate (or lower applicable treaty rate). Anon-U.S.

holder described in the second bullet point immediately above will be subject to tax at a rate of 30% (or a lower applicable treaty rate) on any gain realized, which may be offset by U.S.-source capital losses recognized in the same taxable year. If the third bullet point above applies to anon-U.S. holder, gain recognized by such holder will be subject to tax at generally applicable U.S. federal income tax rates. ESL believes that it has not been a “U.S. real property holding corporation” for U.S. federal income tax purposes at any time during the five-year period preceding the merger.

Information Reporting and Backup Withholding

Payments made in exchange for shares of ESL common stock pursuant to the merger may be subject, under certain circumstances, to information reporting and backup withholding. To avoid backup withholding, a U.S. holder that does not otherwise establish an exemption should complete and return an IRS FormW-9, certifying under penalties of perjury that such U.S. holder is a “United States person” (within the meaning of the Code), that the taxpayer identification number provided is correct, and that such U.S. holder is not subject to backup withholding.

Anon-U.S. holder may be subject to information reporting and backup withholding on the cash received in exchange for ESL common stock unless thenon-U.S. holder establishes an exemption, for example, by properly certifying itsnon-U.S. status on an appropriate version of IRS FormW-8.

Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules may be refunded or credited against a holder’s U.S. federal income tax liability, if any, provided that such holder furnishes the required information to the IRS in a timely manner.

Holders of ESL common stock are urged to consult their tax advisors with respect to the tax consequences of the merger in their particular circumstances, including the applicability and effect of the alternative minimum tax and any state, local,non-U.S. or other tax laws and of changes in those laws.

Regulatory Approvals

General

ESL and TransDigm have each agreed to use their reasonable best efforts to take, or cause to be taken, all actions and do, or cause to be done, and assist and cooperate with the other parties in doing, all things necessary to cause the conditions to the closing of the merger to be satisfied as promptly as reasonably practicable and to effect the closing of the merger as promptly as reasonably practical, including obtaining any requisite approvals and complying with regulatory and foreign investment filings, subject to certain exceptions as described under the section entitled “Proposal 1: Adoption of the Merger Agreement—Terms of the Merger Agreement—Additional Agreements—Efforts to Complete the Merger.” These approvals include approval of, or under, the HSR Act, and from antitrust authorities in certain other jurisdictions, as well as foreign investment approval

under the FrenchCode monétaire et financier. Although we expect that all required regulatory clearances and approvals will be obtained, we cannot assure you that these regulatory clearances and approvals will be timely obtained or obtained at all, or that the granting of these regulatory clearances and approvals will not involve the imposition of additional conditions on the completion of the merger, including the requirement to divest assets, or require changes to the terms of the merger agreement. These conditions or changes could result in the conditions to the closing of the merger not being satisfied.

HSR Act and Other Antitrust Matters

Under the HSR Act and the rules promulgated thereunder by the Federal Trade Commission, the merger cannot be completed until TransDigm and ESL each file a notification and report form with the Federal Trade Commission and the Antitrust Division of the Department of Justice and the applicable waiting period thereunder

has expired or been terminated. A transaction notifiable under the HSR Act may not be completed until the expiration of a30-calendar-day waiting period following the parties’ filings of their respective HSR Act notification and report forms or the early termination of that waiting period. If the Antitrust Division of the Department of Justice or the Federal Trade Commission issues a Request for Additional Information and Documentary Material (a “Second Request”) prior to the expiration of the initial waiting period, the parties must observe a second30-calendar-day waiting period, which would begin to run only after both parties have substantially complied with the Second Request, unless the waiting period is terminated earlier or the parties otherwise agree to extend the waiting period.

ESL and TransDigm filed their respective HSR Act notifications on October 23, 2018. The waiting period expired on November 23, 2018.

At any time before or after consummation of the merger, notwithstanding the expiration or termination of the applicable waiting period under the HSR Act, the Antitrust Division of the Department of Justice or the Federal Trade Commission, or any state, could take such action under the antitrust laws as it deems necessary or desirable in the public interest, including seeking to enjoin the completion of the merger, seeking divestiture of substantial assets of the parties or requiring the parties to license, or hold separate, assets or terminate existing relationships and contractual rights. At any time before or after the completion of the merger, and notwithstanding the expiration or termination of the applicable waiting period under the HSR Act, any state could take such action under the antitrust laws as it deems necessary or desirable in the public interest. Such action could include seeking to enjoin the completion of the merger or seeking divestiture of substantial assets of the parties. Private parties may also seek to take legal action under the antitrust laws under certain circumstances.

The merger is also subject to clearance or approval by antitrust authorities in certain other jurisdictions. The merger cannot be completed until ESL and TransDigm obtain clearance to consummate the merger or applicable waiting periods have expired or been terminated in each applicable jurisdiction. ESL and TransDigm, in consultation and cooperation with each other, will file notifications, as required with antitrust authorities in certain other jurisdictions, as promptly as practicable after the date of the merger agreement. The relevant antitrust authorities could take such actions under the applicable antitrust laws as they deem necessary or desirable, including seeking divestiture of substantial assets of the parties or requiring the parties to license, or hold separate, assets or terminate existing relationships and contractual rights.

There is no assurance that ESL and TransDigm will obtain all required antitrust clearances or approvals on a timely basis, if at all.

Other Regulatory Approvals

Completion of the merger is further subject to the receipt of foreign investment approval under the FrenchCode monétaire et financier from the FrenchMinistre de l’Economie. TransDigm filed its request for approval under the FrenchCode monétaire et financier on November 22, 2018.

There is no assurance that ESL and TransDigm will obtain this approval on a timely basis, if at all.

Legal Proceedings Regarding the Merger

Kent v. Esterline Techs. Corp.

On November 26, 2018, a putative class action complaint was filed against the Company and its Board of Directors in the United States District Court for the District of Delaware under the captionKent v. Esterline Techs. Corp., Case No. 1:18-cv-01862-UNA (D. Del.). The complaint alleges that the preliminary proxy statement issued in connection with TransDigm’s proposed acquisition of the Company omitted material information in violation of Sections 14(a) and 20(a) of the Exchange Act, rendering the proxy statement false and misleading.

The complaint seeks an order enjoining the defendants from proceeding with the proposed transaction, rescinding the proposed transaction or awarding rescissory damages if the transaction is consummated, directing the Company’s directors to file a proxy statement that does not contain any disclosure deficiencies, declaring that the defendants violated Sections 14(a), 20(a) of the Exchange Act, and/or Rule 14a-9, awarding costs, including reasonable attorneys’ and experts’ fees; and granting such other and further relief as the court may deem just and proper. The Company and the individual defendants believe that the claims are without merit and intend to vigorously defend against them.

Rosenfeld v. Esterline Techs. Corp.

On November 29, 2018, a putative class action complaint was filed against the Company and its Board of Directors in the United States District Court for the District of Delaware under the captionRosenfeld v. Esterline Techs. Corp., Case No. 1:18-cv-01891-UNA (D. Del.). The complaint alleges that the preliminary proxy statement issued in connection with TransDigm’s proposed acquisition of the Company omitted material information in violation of Sections 14(a) and 20(a) of the Exchange Act, rendering the proxy statement false and misleading.

The complaint seeks an order maintaining the class action and certifying plaintiff as the class representative and his counsel as class counsel, enjoining the defendants from proceeding with the proposed transaction, rescinding the proposed transaction or awarding rescissory damages if the transaction is consummated, declaring that the defendants violated Sections 14(a), 20(a) of the Exchange Act, and/or Rule 14a-9, awarding costs, including reasonable attorneys’ and experts’ fees; and granting such other and further relief as the court may deem just and proper. The Company and the individual defendants believe that the claims are without merit and intend to vigorously defend against them.

TERMS OF THE MERGER AGREEMENT

The following summary describes certain material provisions of the merger agreement. This summary is not complete and is qualified in its entirety by reference to the merger agreement, which is attached to this proxy statement as Annex A and incorporated into this proxy statement by reference. We encourage you to read the merger agreement carefully in its entirety because this summary may not contain all the information about the merger agreement that is important to you. The rights and obligations of the parties are governed by the express terms of the merger agreement and not by this summary or any other information contained in this proxy statement.

The representations, warranties, covenants and agreements described below and included in the merger agreement were made for purposes of the merger agreement and as of specific dates, were for the benefit of the parties to the merger agreement except as expressly stated therein and may be subject to important qualifications, limitations and supplemental information agreed to by ESL, TransDigm and Merger Sub in connection with negotiating the terms of the merger agreement, including certain qualifications, limitations and supplemental information disclosed in the confidential disclosure schedules to the merger agreement. In addition, the representations and warranties were included in the merger agreement for the purpose of allocating contractual risk between ESL, TransDigm and Merger Sub, and may be subject to standards of materiality applicable to such parties that differ from those generally applicable to investors. In reviewing the representations, warranties and covenants contained in the merger agreement or any description thereof in this summary, it is important to bear in mind that such representations, warranties, covenants and agreements or any descriptions were not intended by the parties to the merger agreement to be characterizations of the actual state of facts or condition of ESL, TransDigm and Merger Sub or any of their respective affiliates or businesses except as expressly stated in the merger agreement. Moreover, information concerning the subject matter of the representations and warranties may change after the date of the merger agreement. In addition, you should not rely on the covenants in the merger agreement as actual limitations on the respective businesses of ESL, TransDigm and Merger Sub because the parties to the merger agreement may take certain actions that are either expressly permitted in the confidential disclosure schedules to the merger agreement or as otherwise consented to by the appropriate party, which consent may be given without prior notice to the public. The merger agreement is described below, and attached as Annex A hereto, with the intention of providing you with information regarding the terms of the merger. Accordingly, the representations, warranties, covenants and other agreements in the merger agreement should not be read alone, and you should read the information provided elsewhere in this document and in our filings with the SEC regarding ESL and our business. Please see “Where You Can Find More Information” beginning on page 101.102.

Structure of the Merger

Upon the terms and subject to the conditions of the merger agreement, on the closing date and at the effective time of the merger, Merger Sub will merge with and into ESL in accordance with the applicable provisions of the DGCL, and the separate corporate existence of Merger Sub will cease and ESL will continue as the surviving corporation in the merger and as a wholly owned subsidiary of TransDigm. The merger will have the effects set forth in the merger agreement and the applicable provisions of the DGCL.

Closing and the Effective Time of the Merger

The closing of the merger will take place on a date to be specified by the parties to the merger agreement, but no later than the third (3rd) business day after the satisfaction or waiver of all of the conditions to closing (described below under the section entitled “Proposal 1: Adoption of the Merger Agreement—Terms of the Merger Agreement—Conditions to the Closing of the Merger” beginning on page 79)80) (except for those conditions that by their nature are to be satisfied at the closing) unless another time or date is mutually agreed to in writing by the parties to the merger agreement.

At the closing, ESL will file a certificate of merger with the Secretary of State of the State of Delaware in accordance with the relevant provisions of the DGCL. The merger will become effective upon the filing of the certificate of merger, or at such other time as is agreed by ESL and TransDigm and set forth in the certificate of merger.

Directors and Officers; Certificate of Incorporation; Bylaws

The directors of Merger Sub immediately prior to the effective time of the merger will, as of the effective time of the merger, be the directors of the surviving corporation until their successors have been duly elected or appointed or until their earlier death, resignation or removal in accordance with the certificate of incorporation and the bylaws of the surviving corporation. The officers of Merger Sub immediately prior to the effective time of the merger will, as of the effective time of the merger, be the officers of the surviving corporation until their successors have been duly elected or appointed or until their earlier death, resignation or removal in accordance with the certificate of incorporation and bylaws of the surviving corporation.

At the effective time of the merger, the certificate of incorporation and bylaws of the surviving corporation will be amended and restated to be the same as the certificate of incorporation and bylaws of Merger Sub, as in effect immediately prior to the effective time of the merger, until thereafter amended as provided therein or by applicable law, except that the name of the surviving corporation shall be “Esterline Technologies Corporation.”

Merger Consideration

Common Stock

At the effective time of the merger and without any action on the part of TransDigm, Merger Sub, ESL or any ESL shareholder, each share of ESL common stock issued and outstanding immediately prior to the effective time of the merger (other than excluded shares), will be converted into the right to receive the merger consideration, without interest and subject to any withholding taxes. All shares, when so converted into the right to receive the merger consideration, will automatically be cancelled and will cease to exist.

If between the date of the merger agreement and the effective time of the merger, a change occurs in the outstanding shares of ESL common stock, including by reason of any reclassification, recapitalization, stock split or combination, division or subdivision of shares, stock dividend (with the record date for such dividend falling during such period), reverse stock split, exchange, consolidation of shares, readjustment or other similar transaction, then any number or amount contained in the merger agreement which is based upon the number of shares of ESL common stock will be appropriately adjusted to provide to the holders of ESL common stock the same economic effect as contemplated by the merger agreement prior to such event.

Treatment of Company Awards

Options. At the effective time of the merger, each Company Option granted under a Company Stock Plan that is outstanding immediately prior to the effective time, whether vested or unvested, will be cancelled and converted into the right to receive an amount in cash (without interest and subject to deduction for any required withholding tax) equal to the product obtained by multiplying (i) the amount by which $122.50 exceeds theper-share exercise price of such Company Option, by (ii) the total number of shares of ESL common stock underlying such Company Option, which cash payment will be made within 5 business days following the effective time. If theper-share exercise price of any such Company Option is equal to or greater than $122.50, such Company Option will be cancelled as of the effective time without the payment of any consideration.

Restricted Stock Units. At the effective time of the merger, each award of Company RSUs granted under a Company Stock Plan that is outstanding immediately prior to the effective time, whether vested or unvested, will be cancelled and converted into the right to receive an amount in cash (without interest and subject to deduction

for any required withholding tax) equal to the product obtained by multiplying (i) $122.50, by (ii) the total number of shares of ESL common stock underlying such Company RSU, which cash payment will be made within 5 business days following the effective time.

Performance Stock Units. At the effective time of the merger, each award of Company PSUs granted under a Company Stock Plan that is outstanding immediately prior to the effective time, whether vested or unvested (treating for this purpose any performance-based vesting condition to which such Company PSU is subject as having been attained at the “target level” with proration), will be cancelled and converted into the right to receive an amount in cash (without interest and subject to deduction for any required withholding tax) equal to the product obtained by multiplying (i) $122.50, by (ii) the total number of shares of ESL common stock underlying such Company PSU (treating for this purpose any performance-based vesting condition to which such Company PSU is subject as having been attained at the “target level” with proration), which cash payment will be made within 5 business days following the effective time.

Employee Stock Purchase Plan. With respect to the Company ESPP, no new offering period will commence, no ESL employee or other person will be permitted to begin participating in the Company ESPP and no current participants will be permitted to increase payroll contributions or make separatenon-payroll contributions to the Company ESPP in respect of the current offering period. The offering period in effect on October 9, 2018 will terminate upon the earlier of December 14, 2018 or 5 trading days prior to the effective time of the merger, and amounts credited to the accounts of participants will be used to purchase shares of ESL common stock in accordance with the terms of the Company ESPP, and such shares will be cancelled and converted into the right to receive the per share merger consideration. The Company ESPP will terminate effective immediately prior to the effective time.

Company SAYE Scheme. With respect to the Company SAYE Scheme, no new rights to purchase ESL common stock will be issued. Participants will be allowed to exercise their Company SAYE Options under the Company SAYE Scheme during the20-day period leading up to the effective time of the merger in accordance with applicable law. To the extent not exercised, at the effective time of the merger, each Company SAYE Option that is outstanding immediately prior to the effective time, whether vested or unvested, will be cancelled and converted into the right to receive an amount in cash (without interest and subject to deduction for any required withholding tax) equal to the product obtained by multiplying (i) the amount by which $122.50 exceeds theper-share exercise price of such Company SAYE Option, by (ii) the quotient of (x) the accumulated amount in the participant’s Company SAYE Scheme savings account immediately prior to the effective time divided by (B) theper-share exercise price of such Company SAYE Option, which cash payment will be made within 5 business days following the effective time. If theper-share exercise price of any such Company SAYE Option is equal to or greater than $122.50, such Company SAYE Option will be cancelled as of the effective time without the payment of any consideration, other than a return of the savings made by the participant in respect of the Company SAYE Option.

Exchange Procedures

Prior to the effective time of the merger, TransDigm shall appoint a bank or trust company mutually agreeable to TransDigm and ESL to act as paying agent for the payment and delivery of the merger consideration. Prior to the effective time of the merger, TransDigm shall deposit, or cause to be deposited, with the designated paying agent, as needed, cash sufficient to pay the merger consideration.

As soon as practicable after the effective time of the merger (and in any event within three (3) business days after the closing date of the merger), TransDigm shall cause the paying agent to mail to each holder of record of shares of ESL common stock:

Upon the surrender of, in the case of shares of ESL common stock represented by a certificate, a certificate for cancellation to the paying agent together with a duly completed and validly executed letter of transmittal in accordance with the instructions thereto (or affidavits in lieu thereof) or, in the case of shares of ESL common stock held as book-entry shares, the receipt of an “agent’s message” by the paying agent, in each case together with such other documents as may reasonably be required by the paying agent, the holder of shares of ESL common stock shall be entitled to receive in exchange therefor the merger consideration into which such shares of ESL common stock have been converted.

In the event of a transfer of ownership of ESL common stock that is not registered in the transfer records of ESL, the merger consideration may be paid to a transferee if the certificate or book-entry share representing such ESL common stock is presented to the paying agent (or, in the case of book-entry shares, proper evidence of such transfer) accompanied by all documents required to evidence and effect such transfer and by evidence that any applicable stock transfer taxes have been paid.

Until such shares of ESL common stock are surrendered as described above, each share of ESL common stock, and any certificate with respect thereto, shall be deemed at any time after the effective time of the merger to represent only the right to receive the merger consideration that the holders of shares of ESL common stock are entitled to receive in respect of such shares.

Any portion of the payment fund (including proceeds of any investment thereof) that remains undistributed to the holders of ESL common stock one (1) year after the closing date of the merger shall be delivered to TransDigm upon demand, and any holder of ESL common stock who has not complied with the exchange procedures in the merger agreement shall thereafter look only to the surviving corporation or TransDigm for payment of its claim for merger consideration without any interest thereon (subject to abandoned property, escheat or similar laws).

Withholding Rights

Each of ESL, TransDigm, the surviving corporation and the paying agent shall be entitled to deduct and withhold from the consideration payable pursuant to the merger agreement to any holder of ESL common stock or equity awards such amounts as it is required to deduct and withhold under U.S. federal tax law or any applicable provision of state, local or foreign tax law.

Appraisal Rights

Any dissenting shares will not be converted into the right to receive the merger consideration. Instead the holders of such dissenting shares will be entitled only to the right to receive payment of the appraised value of such shares of ESL common stock in accordance with Section 262 of the DGCL unless and until such holders fail to perfect or effectively withdraw or lose their rights to appraisal and payment, in which case such shareholder shall be entitled to receive the merger consideration in exchange for such shares of ESL common stock, and such shares of ESL common stock shall not be deemed to be dissenting shares.

Representations and Warranties

The merger agreement contains a number of representations and warranties made by the parties thereto that are subject in some cases to exceptions and qualifications, including “material adverse effect” qualifications. Please see the definition of “Company material adverse effect” in this section beginning on page 69.70. The representations and warranties of ESL in the merger agreement relate to, among other things:

The representations and warranties of TransDigm and Merger Sub in the merger agreement relate to, among other things:

Certain of the representations and warranties made by the parties are qualified as to “knowledge,” “materiality,” a “Company material adverse effect” or a “Parent material adverse effect,” as applicable. For purposes of the merger agreement, a “Company material adverse effect,” means any fact, circumstance, occurrence, effect, change, event or development, which we refer to collectively, as an “effect,” that, individually or in the aggregate, (x) has or would be reasonably expected to have a material adverse effect on the business, financial condition, assets or results of operations of ESL and its subsidiaries, taken as a whole; or (y) has or would reasonably be expected to prevent or materially impair or delay the consummation by ESL of the transactions contemplated by the merger agreement. However, in the case of clause (x), any effect resulting from or arising out of any of the following, individually or in the aggregate, shall not be taken into account in determining whether a Company material adverse effect has occurred or would reasonably be expected to occur:

The circumstances, effects or changes described insub-sections (a), (b), (c), (f), (h), (i) and (j) above will be taken into account in determining whether a Company material adverse effect has occurred to the extent such effect disproportionately impacts ESL and its subsidiaries, taken as a whole, relative to other companies in the industries in which ESL and its subsidiaries operate.

For purposes of the merger agreement, “Parent material adverse effect” means any effect that, individually or in the aggregate, has or would reasonably be expected to prevent or materially impair or delay TransDigm or Merger Sub’s consummation of the transactions contemplated by the merger agreement.

None of the representations and warranties contained in the merger agreement survive the effective time of the merger.

Conduct of Business Pending the Merger

From the date of the merger agreement until the earlier of the effective time of the merger and the termination of the merger agreement, except (i) as expressly set forth in ESL’s disclosure letter, (ii) as expressly permitted or expressly contemplated or required by the merger agreement, or for matters required by a governmental authority or by applicable law or a collective bargaining agreement, or (iii) with the prior written consent of TransDigm (not to be unreasonably withheld, conditioned or delayed), ESL shall, and shall cause each of its subsidiaries to, conduct its businesses in the ordinary course of business consistent with past practice in all

material respects, and use commercially reasonable efforts to (A) preserve intact its present business organizations, goodwill and ongoing businesses, (B) preserve its present relationships with customers, suppliers, vendors, licensors, licensees, governmental authorities and other persons with whom it and they have material business relations, and (C) not to, subject to certain exceptions:

Additional Agreements

No Solicitation

ESL has agreed that it will not, and will cause its subsidiaries not to, and will direct and use its reasonable best efforts to cause its and its subsidiaries’ representatives not to directly or indirectly solicit, initiate or knowingly encourage, or facilitate any proposal, offer or indication of interest (whether or not in writing) from any person, with respect to any of the following:

We refer to any of the transactions contemplated by any of the immediately preceding five bullet points as a company takeover proposal.

Additionally, ESL has agreed that it will not and will cause its subsidiaries not to, and will direct and use its reasonable best efforts to cause its and its subsidiaries’ representatives not to, (i) participate in any discussions or negotiations with any third party regarding, or furnish to any such person, any nonpublic information with respect to any company takeover proposal or any inquiry or proposal that would reasonably be expected to lead to a company takeover proposal, (ii) waive, terminate, modify or release any person from any provision of or grant any permission, waiver or request under any standstill or similar agreement (provided ESL shall not be required to take, or be prohibited from taking, any action otherwise prohibited or required if the Board of Directors determines in good faith (after consultation with financial advisors and outside legal counsel) that such action or inaction would reasonably be expected to be inconsistent with the Board of Directors’ fiduciary duties under applicable law) and (iii) subject to the ESL Alternative Acquisition Termination Right (as described under the section entitled “Proposal 1: Adoption of the Merger Agreement—Terms of the Merger Agreement—Termination of the Merger Agreement—Termination”), enter into any company acquisition agreement (as described under “Proposal 1: Adoption of the Merger Agreement—Terms of the Merger Agreement—Additional Agreements—Change of Recommendation”).

ESL will and will cause its subsidiaries to, and will direct and use its reasonable best efforts to cause its and its subsidiaries’ representatives to, immediately cease all existing solicitations, discussions or negotiations with

any persons with respect to any company takeover proposal, request the prompt return or destruction of all confidential information previously furnished and immediately terminate all physical and electronic data room access previously granted.

Nevertheless, at any time prior to obtaining the ESL shareholder approval, if ESL receives abona fide written company takeover proposal made after the date of the merger agreement that did not result from a material breach of the no solicitation obligations under the merger agreement, and that the Board of Directors determines in good faith (after consultation with financial advisors and outside legal counsel) (i) constitutes or would reasonably be expected to result in a superior company proposal (as described below) and (ii) the failure to take action with respect to such company takeover proposal would reasonably be expected to be inconsistent with the Board of Directors’ fiduciary duties under applicable law, then ESL and its representatives may furnish information to the person making the company takeover proposal pursuant to a confidentiality agreement containing terms no less restrictive than those contained in the confidentiality agreement between ESL and TransDigm (provided that all such information has been, or is substantially concurrently, provided to TransDigm) and participate in discussions regarding the terms of the company takeover proposal, including the terms of an agreement with respect to the company takeover proposal.

Change of Recommendation

Subject to the following paragraph, the Board of Directors will not change its recommendation that the holders of shares of ESL common stock vote “FOR” the merger proposal (the changing of such recommendation, being referred to as a “company adverse recommendation change”). Under the merger agreement, a company adverse recommendation change will occur if the Board of Directors (1) withdraws, changes, qualifies, withholds or modifies in any manner adverse to TransDigm or Merger Sub, its recommendation that the holders of shares of ESL common stock vote “FOR” the merger proposal, proposes publicly to do any of the foregoing or fails to make its recommendation when required under the merger agreement, (2) adopts, approves, recommends or declares advisable any company takeover proposal or proposes publicly to do any of the foregoing, (3) fails to include its recommendation that the holders of shares of ESL common stock vote “FOR” the merger proposal in this proxy statement, (4) subject to certain exceptions, including the last paragraph of “Proposal 1: Adoption of the Merger Agreement—Terms of the Merger Agreement—Additional Agreements—No Solicitation” and the following paragraphs, authorizes, permits, approves, recommends or declares advisable, or causes or allows ESL or any of its subsidiaries to execute or enter into any letter of intent, memorandum of understanding, agreement in principle, agreement or commitment constituting, or that would reasonably be expected to lead to, any company takeover proposal, or requiring, or that would reasonably be expected to cause, ESL to abandon or terminate the merger agreement or delay in any material respects or fail to consummate the transactions contemplated thereby, which we refer to as a company acquisition agreement, or proposes publicly to do any of the foregoing, or (5) in the event of a disclosure relating to the approval, recommendation or declaration of advisability by the Board of Directors with respect to a company takeover proposal, fails to publicly state that the Board of Directors expressly rejects such company takeover proposal or expressly reaffirm its recommendation that the holders of shares of ESL common stock vote “FOR” the merger proposal.

Prior to obtaining the ESL shareholder approval, the Board of Directors may make a company adverse recommendation change or may authorize and direct that ESL terminate the merger agreement, in each case, (i) in response to the receipt of abona fidewritten company takeover proposal (with applicable thresholds in the definition of a company takeover proposal of fifty percent (50%) instead of twenty percent (20%)) that the Board of Directors determines in good faith (after consultation with ESL’s outside legal counsel and financial advisor) is more favorable to ESL’s shareholders than the merger and the other transactions contemplated by the merger agreement and is reasonably capable of being completed in a reasonable timeframe, taking into account the legal, financial, regulatory and other aspects of such company takeover proposal and such other factors that are deemed relevant by the Board of Directors (such proposal being referred to as a “superior company proposal”), and (ii) if the Board of Directors determines in good faith (after consultation with ESL’s outside legal counsel and financial

advisor) that the failure to make a company adverse recommendation change or to terminate the merger agreement, as applicable, would reasonably be expected to be inconsistent with the Board of Directors’ fiduciary duties under applicable law; subject to providing three (3) business days prior written notice to TransDigm of its proposed decision to change its recommendation or terminate the merger agreement (and the basis therefor) and, if requested by TransDigm, during such three (3) business day period, negotiating in good faith with TransDigm regarding revisions to the merger agreement committed to in writing by TransDigm.

Prior to obtaining the ESL shareholder approval, the Board of Directors may also make a company adverse recommendation change (i) in response to any effect that does not relate to a company takeover proposal and occurs after the date of the merger agreement that prior to date of the merger agreement was unknown and not reasonably foreseeable that the Board of Directors determines in good faith (after consultation with ESL’s outside legal counsel and financial advisor) would reasonably be expected to materially adversely affect the expected benefits of the merger to the ESL shareholders from a financial point of view (such event being referred to as a “company intervening event”), and (ii) if the Board of Directors determines in good faith (after consultation with ESL’s outside legal counsel and financial advisor) that the failure to make a company adverse recommendation change would reasonably be expected to be inconsistent with the Board of Directors’ fiduciary duties under applicable law; subject to providing three (3) business days prior written notice to TransDigm of its proposed decision to change its recommendation or terminate the merger agreement (and the basis therefor) and, during such three (3) business day period, negotiating in good faith with TransDigm regarding revisions to the merger agreement or other mitigating factors or structural changes proposed by TransDigm.

Efforts to Obtain Required Shareholder Approvals

Unless the merger agreement has been earlier terminated, including pursuant to ESL’s right to terminate the merger agreement to enter into an agreement with respect to a superior company proposal (see “Proposal 1: Adoption of the Merger Agreement—Terms of the Merger Agreement—Additional Agreements—Change of Recommendation”), ESL has agreed to hold a special meeting of its shareholders and to use its reasonable best efforts to secure the ESL shareholder approval. ESL has agreed to include the Board of Directors’ recommendation that the holders of shares of ESL common stock vote “FOR” the merger proposal in this proxy statement.

Efforts to Complete the Merger

The parties have each agreed to use their reasonable best efforts to take, or cause to be taken, all actions and do, or cause to be done, and assist and cooperate with the other parties to the merger agreement in doing, all things necessary to cause the conditions to the closing to be satisfied as promptly as reasonably practicable and to effect the closing as promptly as reasonably practicable.

To the extent necessary, proper or advisable in order to (i) obtain clearance under the HSR Act or any other required consent of a governmental authority under an antitrust law or (ii) obtain approval under the FrenchCodemonétaire et financier from the FrenchMinistre de l’Economie, (iii) avoid the entry of, or to have vacated, lifted, reversed or overturned any judgment that prohibits, prevents or restricts consummation of, or impedes, interferes with or delays the closing of the merger before the end date or (iv) effect the expiration or termination of any waiting period that would otherwise have the effect of preventing, prohibiting or restricting consummation of the merger, TransDigm has agreed to take all reasonable actions to eliminate each and every impediment that may be asserted by a governmental authority with respect to the merger so as to enable the closing of the merger to occur as soon as reasonably possible, including:

Notwithstanding TransDigm’s obligations summarized in the immediately foregoing paragraph, TransDigm is only required to take such actions if (x) such action is conditioned upon the closing of the merger and becomes effective only from and after the effective time of the merger and (y) such actions do not relate to the businesses, assets, properties, product lines, equity interests, relationships, ventures, contractual rights, or obligations of TransDigm, ESL and their respective subsidiaries that, directly or indirectly, generated in the aggregate more than $90,000,000 in EBITDA (as defined in the merger agreement) for the twelve (12) months ended September 30, 2018.

In addition, TransDigm and ESL each agreed to, among other things:

Employees and Employee Benefits

From and after the effective time of the merger, TransDigm will or will cause the surviving corporation to assume, honor and fulfill all of the obligations under the ESL benefit plans, other than any equity-based ESL benefit plans, in accordance with their terms.

Except where applicable law, any ESL benefit plan or a collective bargaining agreement requires more favorable treatment, during the period commencing at the effective time of the merger and ending on the first anniversary thereof, TransDigm is obligated to provide, or to cause to be provided, to each employee of ESL or any of its subsidiaries who continues to be employed by TransDigm or any of its subsidiaries, including the surviving corporation, with (i) at least the same level of base salary or hourly wage rate, as the case may be, that was provided to each such employee immediately prior to the effective time of the merger, (ii) target incentive compensation opportunities (including annual cash performance bonus), other than any equity-based incentive opportunities, that are no less favorable than those in effect with respect to each such employee immediately prior to the effective time of the merger, (iii) severance pay and benefits to any such employee who incurs a qualifying termination at any time during theone-year period following the effective time of the merger at levels that are no less favorable than the levels of such severance pay and benefits as in effect under the applicable ESL benefit plans immediately prior to the effective time of the merger, and (iv) other compensation and employee benefits (other than equity based opportunities and benefits) which are no less favorable in the aggregate (including with respect to the proportion of employee cost) to the compensation and employee benefits provided to such employee immediately prior to the effective time of the merger.

From and after the effective time of the merger, TransDigm will cause any employee benefit plans in which any continuing employee of ESL or any of its subsidiaries is eligible to participate following the effective time of the merger to recognize for all purposes, including eligibility, vesting, level of benefits, any waiting period and benefit accrual thereunder, service with ESL and its subsidiaries and their respective predecessor entities, in each case, to the same extent such service was recognized under a comparable ESL benefit plan prior to the effective

time of the merger (except to the extent it would result in a duplication of benefits with respect to the same period of service).

With respect to any health or welfare benefit plan in which any continuing employee of ESL or any of its subsidiaries is eligible to participate following the effective time of the merger which replaces coverage under a comparable ESL benefit plan in which such employee participated immediately prior to the effective time of the merger, TransDigm will (i) waive all limitations as to preexisting condition exclusions and all waiting periods with respect to participation and coverage requirements applicable to each such employee to the extent waived or satisfied under the comparable ESL benefit plan in which the employee participated immediately prior to the effective time of the merger, (ii) provide that the employee will be immediately eligible to participate in any such health or welfare benefit plan, without any waiting period, to the extent such employee was eligible to participate in the comparable ESL benefit plan immediately prior to the effective time of the merger, and (iii) credit each employee for any applicable amounts paid or eligible expenses incurred by such employee (and his or her covered dependents) under the terms of the ESL benefit plan toward satisfying any applicable deductible,co-payment orout-of-pocket requirements under the applicable health and welfare benefit plan that replaces such ESL benefit plan for the plan year in which the effective time of the merger occurs.

Promptly following the effective time of the merger, TransDigm will establish an annual incentive plan or plans for the remainder of the year in which the effective time of the merger occurs, which annual incentive plans will provide continuing employees of ESL or any of its subsidiaries with a bonus opportunity at least equal to that provided under the applicable annual incentive plan or program maintained by ESL or its subsidiaries in which such employee participated immediately prior to the effective time of the merger, other than any equity-based incentive plans or programs,pro-rated for the remainder of such year.

ESL will, and will cause its subsidiaries to, and TransDigm will, and will cause its affiliates to, cooperate fully in satisfying all legal or contractual requirements to provide notice to, or carry out any information and/or consultation procedure with, any employee or groups of employees of ESL or any of its subsidiaries, or any labor or trade union, labor organization, works council or any other employee representative or employee representative body, which is representing any employee of ESL or any of its subsidiaries, in connection with the transactions contemplated by the merger agreement.

Notwithstanding anything in the merger agreement to the contrary, (i) the foregoing provisions of the merger agreement are solely for the benefit of the parties to the merger agreement, (ii) nothing therein is intended to, or will, constitute the establishment or adoption of or an amendment to any employee benefit plan, and (iii) none of the continuing employees of ESL or any of its subsidiaries or any other individual associated therewith will be regarded for any purpose as a third-party beneficiary of the merger agreement or have the right to enforce the provisions of the merger agreement, including in respect of continued employment (or resumed employment). Nothing in the merger agreement will be deemed to limit the right of Parent or any of its subsidiaries, including the surviving corporation, to terminate the employment of any continuing employee of ESL or its subsidiaries or alter theat-will employment relationship of any such employee.

Directors’ and Officers’ Indemnification and Insurance

For six (6) years from and after the effective time of the merger, TransDigm and the surviving corporation will indemnify and hold harmless each director or officer of ESL or any of its subsidiaries who was a director or officer prior to or as of the effective time of the merger and their heirs and personal representatives against all claims arising out of or pertaining to the fact that the foregoing is or was a director or officer of ESL or any of its subsidiaries, whether asserted or claimed prior to, at or after the effective time, as provided in their respective organizational documents and any indemnification or other similar agreements and to the fullest extent permitted under applicable law. For six (6) years from and after the effective time of the merger, TransDigm will not permit any indemnification, advancement of expenses or exculpation provision in such organizational documents or such indemnification agreements to be amended, repealed or otherwise modified in any manner that would

adversely affect the rights of the indemnified parties thereunder, unless such amendment, repeal or modification is required by applicable law.

For a period of six (6) years from and after the effective time of the merger, TransDigm will and will cause the surviving corporation either to cause to be maintained in effect the current policies of directors’ and officers’ liability insurance and fiduciary liability insurance maintained by ESL or its subsidiaries or provide substitute policies for ESL and its current and former directors, officers, employees and agents who are currently covered by such liability insurance coverage currently maintained by ESL, in either case, with limits not less than the existing coverage and having other terms not less favorable to the insured persons than such liability insurance coverage currently maintained by ESL with respect to claims arising from facts or events that occurred on or before the effective time of the merger, except that in no event shall the surviving corporation be required to pay with respect to such insurance policies in respect of any one (1) policy year more than three hundred percent (300%) of the aggregate the annual premium most recently paid by ESL prior to the date of the merger agreement, which we refer to as the maximum amount, and if TransDigm or the surviving corporation is unable to obtain such insurance it shall obtain as much comparable insurance as possible within such six (6) year period for an aggregate amount equal to the maximum amount. However, in lieu of such insurance, prior to the closing date ESL may, at its option, purchase a fully prepaid andnon-cancellable “tail” directors’ and officers’ liability insurance policy and fiduciary insurance policy for ESL and its current and former directors and officers who are currently covered by such liability insurance coverage currently maintained by ESL, such tail insurance to provide coverage not less than the existing coverage and to have other terms not less favorable to the insured persons than the directors’ and officers’ liability insurance coverage currently maintained by ESL with respect to claims arising from facts or events that occurred on or before the effective time of the merger; provided that in no event shall the cost of any such tail insurance in respect of any one (1) policy year exceed the maximum amount.

Transaction Litigation

ESL will promptly notify TransDigm of any shareholder litigation arising from the merger agreement or the merger, keep TransDigm reasonably informed regarding any such shareholder litigation and give TransDigm the opportunity to participate (at TransDigm’s expense) in, and reasonably cooperate with TransDigm in, the defense or settlement of any shareholder litigation against ESL, any of its subsidiaries or any of their representatives, including members of the Board of Directors. ESL will not settle any such shareholder litigation without TransDigm’s prior written consent (such consent not to be unreasonably withheld or delayed unless such settlement does not include a full release of TransDigm and its affiliates).

Financing and Financing Cooperation

In connection with entering into the merger agreement, TransDigm entered into a commitment letter, dated as of October 9, 2018, with Morgan Stanley Senior Funding, Inc., Credit Suisse Loan Funding LLC and Credit Suisse AG, pursuant to which, upon the terms and subject to the conditions set forth therein, the financing sources party thereto have committed to provide a $3.7 billion senior secured term facility subject to customary conditions precedent. TransDigm expects to finance the merger through proceeds from such debt financing and cash on hand.

TransDigm will use, and shall cause its affiliates to use, their reasonable best efforts to take, or cause to be taken, all actions, and to do, or cause to be done, all things necessary or advisable to arrange and to obtain the proceeds of the debt financing on terms and conditions no less favorable to TransDigm than those contained in the commitment documents. ESL will use, and shall cause its subsidiaries to use, its and their reasonable best efforts to cooperate with TransDigm prior to closing, as reasonably requested by TransDigm and at TransDigm’s sole expense, in connection with TransDigm’s arrangement of its debt financing.

Other Covenants and Agreements

The merger agreement contains certain other covenants and agreements, including covenants relating to, among other things:

Conditions to the Closing of the Merger

The respective obligations of TransDigm, Merger Sub and ESL to effect the closing of the merger are subject to the satisfaction or waiver on or prior to the closing of the following conditions:

The obligations of TransDigm and Merger Sub to consummate the merger will be further subject to the satisfaction or waiver at or prior to the closing date of the following conditions:

The obligation of ESL to consummate the merger will be further subject to the satisfaction or waiver on or prior to the closing date of the following conditions:

Termination of the Merger Agreement

Termination

The merger agreement may be terminated and the merger may be abandoned at any time prior to the effective time of the merger:

Effect of Termination

If the merger agreement is terminated as described above under the section entitled “Proposal 1: Adoption of the Merger Agreement—Terms of the Merger Agreement—Termination of the Merger Agreement—Termination” beginning on page 81,82, the merger agreement will immediately become void and have no effect, without any liability or obligation on the part of any party based on, arising out of or relating to the merger agreement, except for:

For the purpose of the merger agreement, the term intentional breach means a material breach of the merger agreement that is a consequence of an act or omission by the breaching party with the knowledge or intent that the taking of, or the omission of taking, such act would, or would reasonably be expected to, cause or constitute a material breach of the merger agreement.

Termination Fee

Under the merger agreement, ESL will be required to pay a termination fee of $128,855,000 in connection with a termination of the merger agreement under the following circumstances:

If the merger agreement is terminated under circumstances in which ESL is obligated to pay TransDigm the termination fee, then ESL shall have no further liability with respect to the merger agreement or the transactions contemplated thereby to TransDigm, Merger Sub or their respective affiliates or representatives, and payment of the termination fee and such costs and expenses (as described under “Proposal 1: Adoption of the Merger Agreement—Terms of the Merger Agreement—Termination of the Merger Agreement—Expense Reimbursement”) shall be TransDigm’s sole and exclusive remedy. In no event will ESL be required to pay the termination fee described above on more than one occasion.

Expense Reimbursement

If ESL fails to promptly pay any amount due to TransDigm in connection with a termination described in “Proposal 1: Adoption of the Merger Agreement—Terms of the Merger Agreement—Termination of the Merger Agreement—Termination Fee,” it shall also pay TransDigm’s reasonable, documentedout-of-pocket costs and expenses incurred in connection with a suit that results in a judgment against ESL for such amount, together with interest on such amount or portion thereof at the prime rate published by theWall Street Journal in effect on the date such payment was required through the date of payment (or such lesser rate as is the maximum permitted by applicable law).

Expenses

Except for the provisions described above under the section entitled “Proposal 1: Adoption of the Merger Agreement—Terms of the Merger Agreement—Termination of the Merger Agreement—Expense Reimbursement,” generally, each of ESL, TransDigm and Merger Sub will pay their own fees, costs and expenses incurred in connection with the merger agreement and the transactions contemplated by the merger agreement. However, TransDigm will pay one hundred percent (100%) of the filing fees associated with regulatory and foreign investment filings or consents.

Amendment and Waiver

Amendment

The merger agreement may be amended, modified or supplemented by the parties at any time before the effective time of the merger (including after the receipt of the ESL shareholder approval) by a written instrument executed by each party to the merger agreement. However, after the receipt of the ESL shareholder approval, the parties may not amend the merger agreement in a manner that requires further approval by the shareholders of ESL without having received such further approval. The provisions expressly relating to the financing sources may not be amended, modified or supplemented or waived in a manner that adversely affects any financing source without the prior written consent of each such adversely affected party.

Extension; Waiver

At any time prior to the effective time of the merger, with certain exceptions, the parties to the merger agreement may:

Governing Law; Venue

The merger agreement is governed by the laws of the state of Delaware (without giving effect to conflict of law principles thereof), except that claims and causes of action involving the financing sources in any way relating to the merger agreement or the transactions contemplated thereby, the debt letters, the financing or the performance thereof or related will be governed by the laws of the state of New York (without giving effect to conflict of law principles thereof).

The exclusive venue for claims is the Court of Chancery of the State of Delaware and any appellate court therefrom within the State of Delaware, or, to the extent such court does not have subject matter jurisdiction, the Superior Court of the State of Delaware or the United States District Court for the District of Delaware, except that claims and causes of action involving the financing sources in any way relating to the merger agreement or the transactions contemplated thereby, the debt letters, the financing or the performance thereof or related will be subject to the exclusive jurisdiction of the United States Federal and New York State courts located in the borough of Manhattan.

Specific Performance

The parties are entitled to injunctions or other equitable relief to prevent breaches or threatened breaches of the merger agreement and to enforce specifically the performance of the terms and provisions of the merger agreement in addition to any other remedy to which they are entitled at law or equity.

PROPOSAL 2: ADVISORY VOTE ON MERGER-RELATED EXECUTIVE COMPENSATION ARRANGEMENTS

The Merger-Related Compensation Proposal

Section 14A of the Exchange Act, which was enacted as part of the Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010, requires that we provide our shareholders with the opportunity to vote to approve, on an advisorynon-binding basis, the payment of certain compensation that will or may become payable by ESL to its named executive officers in connection with the merger. For a summary of the terms and conditions of the payments described below, see the section of this proxy statement entitled “Proposal 1: Adoption of the Merger Agreement—The Merger—Interests of the Directors and Executive Officers of ESL in the Merger” beginning on page 53.

The information set forth in the table below titled “Quantification of Potential Payments and Benefits to Named Executive Officers in Connection with the Merger,” is intended to comply with Item 402(t) of the SEC’s RegulationS-K, which requires disclosure of information about certain compensation for each named executive officer of ESL that is based on, or otherwise relates to, the merger. The amounts reported below are estimates based on multiple assumptions that may or may not actually occur, including assumptions described in this proxy statement, and do not reflect certain actions that may occur before completion of the merger. As a result, the actual amounts, if any, to be received by a named executive officer may materially differ from the amounts set forth below. In particular, for purposes of calculating the amounts set forth in the table below (as determined on November 27, 2018), we have assumed that (1) the merger waswill be completed on NovemberApril 1, 2018 (the latest practicable date prior to filing this proxy statement)2019 and each named executive officer’s outstanding equity awards, base salary and target bonus amounts are calculated as of such date, (2) the employment of each of the named executive officers (other than Mr. George and Ms. Mason whose employment actually terminated prior to November 1, 2018)the date of this proxy statement) was terminated either by ESL without cause or by the named executive officer for good reason immediately thereafter, (3) each named executive officer would receive approximately the amounts set forth in the table below, based on a $122.50 per share price for each share of ESL common stock (which is the per share merger consideration) (and without subtraction of applicable withholding taxes through net settlement or otherwise) and (4) no amounts payable to the named executive officers under any of ESL’s nonqualified deferred compensation plans will be enhanced or accelerated in connection with the merger. Depending on when the merger is completed, directors and executive officers may receive a grant of additional equity awards for the 2019 fiscal year, which amounts are not determinable at this time and therefore are not reflected in the table. Mr. George and Ms. Mason are listed as named executive officers in the table because they appear as named executive officers in ESL’s annual proxy statement for the fiscal year ended September 29, 2017.

Quantification of Potential Payments and Benefits to Named Executive Officers in Connection with the Merger

The table below provides information on the estimated value of unvested Company Options held by the named executive officers. The amounts shown with respect to each Company Option represent the product of (a) the excess, if any, of $122.50 over the applicableper-share exercise price of such Company Option, multiplied by (b) the number of shares of ESL common stock subject to such Company Option:

The table below provides details on the estimated value of unvested Company RSUs and Company PSUs (treating for this purpose any performance-based vesting condition to which such Company PSU is subject as having been attained at the “target level” with proration). A portion of the RSUs granted in fiscal 2019 were awarded in lieu of PSUs, and such awards held by each of the named executive officers (other than Mr. George and Ms. Mason) at the time of closing will be pro-rated to the closing date, rather than being fully accelerated. The amounts shown represent the product (a) $122.50 and (b) the number of shares of ESL common stock underlying such Company RSUs or Company PSUs, respectively.