Exhibit

Exhibit 3.1

FIFTH AMENDED AND RESTATED

CERTIFICATE OF INCORPORATION

ESTERLINE TECHNOLOGIES CORPORATION

FIRST: The name of the corporation (which is hereinafter referred to as the “Corporation”) is Esterline Technologies Corporation.

SECOND: The address of the Corporation’s registered office in the State of Delaware is Corporation Trust Center, 1209 Orange Street, in the City of Wilmington, County of New Castle, Delaware 19801. The name of its registered agent at such address is The Corporation Trust Company.

THIRD: The purpose of the Corporation is to engage in any lawful act or activity for which corporations may be organized under the General Corporation Law of the State of Delaware (the “DGCL”).

FOURTH: The total number of shares of stock that the Corporation shall have authority to issue is five thousand (5,000) shares, all of which shall be Common Stock, $0.01 par value per share.

FIFTH: Meetings of stockholders shall be held at such place, within or without the State of Delaware, as may be designated by or in the manner provided in the By-Laws of the Corporation (“By-Laws”), or, if not so designated, at the registered office of the Corporation in the State of Delaware. Election of directors need not be by written ballot unless and to the extent that the By-Laws so provide.

SIXTH: In furtherance and not in limitation of the powers conferred by law, the Board of Directors of the Corporation (the “Board”) is expressly authorized and empowered to make, alter and repeal the By-Laws by a majority vote at any regular or special meeting of the Board or by written consent.

SEVENTH: The Corporation reserves the right at any time, and from time to time, to amend, alter, change or repeal any provision contained in this Fifth Amended and Restated Certificate of Incorporation (this “Certificate of Incorporation”), and other provisions authorized by the laws of the State of Delaware at the time in force may be added or inserted, in the manner now or hereafter prescribed by law, and all rights, preferences and privileges of whatever nature conferred upon stockholders, directors or any other persons whomsoever by and pursuant to this Certificate of Incorporation in its present form or as hereafter amended are granted subject to the rights reserved in this Article Seventh.

EIGHTH: No director shall be personally liable to the Corporation or any stockholder for monetary damages for breach of fiduciary duty as a director; provided, however, that the foregoing shall not eliminate or limit the liability of a director:

(i) for any breach of the director’s duty of loyalty to the Corporation or its stockholders;

(ii) for acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law;

(iii) under Section 174 of the DGCL; or

(iv) for any transaction from which the director derived an improper personal benefit.

If the DGCL is amended after the date hereof to authorize corporate action further eliminating or limiting the personal liability of directors, then the liability of a director of the Corporation shall be eliminated or limited to the fullest extent permitted by the DGCL, as so amended.

NINTH: (1) With respect to any matter existing or occurring at or prior to the effective time (the “Effective Time”) of the merger contemplated by the Agreement and Plan of Merger, dated as of October 9, 2018, as amended by the First Amendment to Agreement and Plan of Merger, dated as of October 10, 2018, by and among the Corporation, TransDigm Group Incorporated and Thunderbird Merger Sub Inc.:

(a) each person who was or is a party or is threatened to be made a party to any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative or investigative, by reason of the fact that he is or was a director or officer of the Corporation, or is or was serving at the request of the Corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise, including service with respect to employee benefit plans, whether the basis of such proceeding is alleged action in an official capacity as a director, officer, employee or agent or in any other capacity while serving as a director, officer, employee or agent, shall be indemnified and held harmless by the Corporation to the fullest extent authorized or permitted by the DGCL, as the same exists or may hereafter be amended (but, in the case of any such amendment, only to the extent that such amendment permits the Corporation to provide broader indemnification rights that said law permitted the Corporation to provide prior to such amendment), against all expense, liability and loss (including attorneys’ fees, judgments, fines, ERISA excise taxes or penalties and amounts paid or to be paid in settlement) actually and reasonably incurred by such person in connection with such action, suit or proceeding, and such indemnification shall continue as to a person who has ceased to be a director, officer, employee or agent and shall inure to the benefit of the heirs, executors and administrators or such person; provided, however, that, except as provided in paragraph (1)(b) of this Article Ninth, the Corporation shall indemnify any such person seeking indemnification in connection with an action, suit or proceeding (or part thereof) initiated by such person only if such action, suit or proceeding (or part thereof) was authorized by the board of directors of the Corporation. The right to indemnification conferred in paragraph (1) of this Article Ninth shall be a contract right and shall include the right to be paid by the Corporation the expenses incurred in defending any such action, suit or proceeding in advance of its final disposition; provided, however, that if the DGCL requires, the payment of such expenses incurred by a director or officer in his capacity as such in advance of the final disposition of any such action, suit or proceeding shall be made only upon receipt by the Corporation of an undertaking by or on behalf of such director or officer to repay all amounts so advanced if it shall ultimately be determined that such director or officer is not entitled to be indemnified under paragraph (1) of this Article Ninth or otherwise. The Corporation may, by action of its board of directors, provide indemnification to employees and agents of the Corporation with the same scope and effect as the foregoing indemnification of directors and officers;

(b) if a claim under paragraph (1)(a) of this Article Ninth is not paid in full by the Corporation within thirty days after a written claim has been received by the Corporation, the claimant may at any time thereafter bring suit against the Corporation to recover the unpaid amount of the claim and, if successful in whole or in part, the claimant shall be entitled to be paid also the expense of prosecuting such claim. It shall be a defense to any such action (other than an action brought to enforce a claim for expenses incurred in defending any proceeding in advance of its final disposition where the required undertaking, if any is required, has been tendered to the Corporation) that the claimant has not met the standards of conduct which make it permissible under the DGCL for the Corporation to indemnify the claimant for the amount claimed, but the burden of proving such defense shall be on the Corporation. Neither the failure of

the Corporation (including its board of directors, independent legal counsel, or its stockholders) to have made a determination prior to the commencement of such action that indemnification of the claimant is proper in the circumstances because he has met the applicable standard of conduct set forth in the DGCL, nor an actual determination by the Corporation (including its board of directors, independent legal counsel, or its stockholders) that the claimant has not met such applicable standard of conduct, shall be a defense to the action or create a presumption that the claimant has not met the applicable standard of conduct; and

(c) the right to indemnification under paragraph (1) and the payment of expenses incurred in defending a proceeding in advance of its final disposition conferred in this Section shall not be exclusive of any other right which any person may have or hereafter acquire under any statute, provision of the Certificate of Incorporation, bylaw, agreement, vote of stockholders or disinterested directors or otherwise.

(2) With respect to any matter existing or occurring after the Effective Time:

(a)(i) the Corporation shall indemnify to the fullest extent permitted under and in accordance with the laws of the State of Delaware any person who was or is a party or is threatened to be made a party to any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative or investigative (other than an action by or in the right of the Corporation) by reason of the fact that the person is or was a director or officer of the Corporation, or is or was serving at the request of the Corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise, against expenses (including attorneys’ fees), judgments, fines and amounts paid in settlement actually and reasonably incurred by the person in connection with such action, suit or proceeding if the person acted in good faith and in a manner the person reasonably believed to be in or not opposed to the best interests of the Corporation, and, with respect to any criminal action or proceeding, had no reasonable cause to believe the person’s conduct was unlawful. The termination of any action, suit or proceeding by judgment, order, settlement, conviction, or upon a plea of nolo contendere or its equivalent, shall not, of itself, create a presumption that the person did not act in good faith and in a manner which the person reasonably believed to be in or not opposed to the best interests of the Corporation, and, with respect to any criminal action or proceeding, had reasonable cause to believe that the person’s conduct was unlawful; and

(ii) the Corporation shall indemnify any person who was or is a party or is threatened to be made a party to any threatened, pending or completed action or suit by or in the right of the Corporation to procure a judgment in its favor by reason of the fact that the person is or was a director or officer of the Corporation, or is or was serving at the request of the Corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise against expenses (including attorneys’ fees) actually and reasonably incurred by the person in connection with the defense or settlement of such action or suit if the person acted in good faith and in a manner the person reasonably believed to be in or not opposed to the best interests of the Corporation, except that no indemnification shall be made in respect of any claim, issue or matter as to which such person shall have been adjudged to be liable to the Corporation unless and only to the extent that the Delaware Court of Chancery or the court in which such action or suit was brought shall determine upon application that, despite the adjudication of liability but in view of all the circumstances of the case, such person is fairly and reasonably entitled to indemnity by the Corporation for such expenses which the Delaware Court of Chancery or such other court shall deem proper;

(b) expenses (including attorneys’ fees) incurred in defending any civil, criminal, administrative or investigative action, suit or proceeding shall (in the case of any action, suit or

proceeding against a director of the Corporation) or may (in the case of any action, suit or proceeding against an officer, trustee, employee or agent of the Corporation) be paid by the Corporation in advance of the final disposition of such action, suit or proceeding as authorized by the Board upon receipt of an undertaking by or on behalf of a person so indemnified to repay such amount if it shall ultimately be determined that he or she is not entitled to be indemnified by the Corporation as authorized in paragraph (2) of this Article Ninth; and

(c) the indemnification and other rights set forth in paragraph (2) of this Article Ninth shall not be exclusive of any provisions with respect thereto in the By-Laws or any other contract or agreement between the Corporation and any officer, director, employee or agent of the Corporation.

(3) The Corporation shall have the power to purchase and maintain insurance, at its expense, on behalf of any person who is or was a director, officer, employee or agent of the Corporation, or is or was serving at the request of the Corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise against any liability asserted against such person and incurred by such person in any such capacity, or arising out of such person’s status as such, whether or not the Corporation would have the power to indemnify such person against liability under this Article Ninth and applicable law, including the DGCL.

(4) Neither the amendment nor repeal of this Article Ninth, nor the adoption of any provision of this Certificate of Incorporation inconsistent with this Article Ninth, shall eliminate or reduce the effect of this Article Ninth in respect of any matter occurring before such amendment, repeal or adoption of an inconsistent provision or in respect of any cause of action, suit or claim relating to any such matter which would have given rise to a right of indemnification or right to the reimbursement of expenses pursuant to this Article Ninth if such provision had not been so amended or repealed or if a provision inconsistent therewith had not been so adopted.