Exhibit 3.1

SECOND AMENDED AND RESTATED CERTIFICATE OF INCORPORATION

OF

TRANSDIGM GROUP INCORPORATED

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TRANSDIGM GROUP INCORPORATED (formerly TD Holding Corporation), a corporation organized and existing under the laws of the State of Delaware, hereby certifies as follows:

1. The name of the corporation is TransDigm Group Incorporated. TransDigm Group Incorporated was originally incorporated under the laws of the State of Delaware under the name TD Holding Corporation, and the original Certificate of Incorporation of the corporation was filed with the Secretary of State of the State of Delaware on July 8, 2003. TransDigm Group Incorporated filed an amendment to its Certificate of Incorporation with the Secretary of State of the State of Delaware on January 19, 2006, pursuant to which the name of the corporation was changed from TD Holding Corporation to TransDigm Group Incorporated.

2. The Amended and Restated Certificate of Incorporation was filed by the corporation with the Secretary of State of the State of Delaware on March 14, 2006.

3. Pursuant to Sections 242 and 245 of the General Corporation Law of the State of Delaware, this Second Amended and Restated Certificate of Incorporation restates and integrates and further amends the provisions of the Amended and Restated Certificate of Incorporation of TransDigm Group Incorporated.

4. This Second Amended and Restated Certificate of Incorporation was duly adopted pursuant to a resolution adopted by the Board of Directors of TransDigm Group Incorporated and approved by the holders of the requisite number of shares of capital stock of TransDigm Group Incorporated in accordance with Section 242 of the Delaware General Corporation Law.

5. TransDigm Group Incorporated’s certificate of incorporation shall be amended and restated in its entirety to read as follows:

ARTICLE I

The name of the corporation (the “Corporation”) is:

TransDigm Group Incorporated

ARTICLE II

The address of the registered office of the Corporation in the State of Delaware is Corporation Service Company, 2711 Centerville Road, Suite 400, Wilmington, Delaware 19808. The name of the registered agent of the Corporation at such address is Corporation Service Company, in the county of New Castle.

ARTICLE III

The nature of the business or purposes to be conducted or promoted by 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 as now in effect or hereafter amended (the “DGCL”).

ARTICLE IV

The total number of shares of all classes of stock which the Corporation shall have authority to issue is (a) 224,400,000 shares of common stock, par value $0.01 per share (the “Common Stock”), and (b) 149,600,000 shares of preferred stock, par value $0.01 per share (the “Preferred Stock”). Subject to the rights, if any, of the holders of any outstanding series of Preferred Stock, the number of authorized shares of any of the Common Stock or the Preferred Stock may be increased or decreased (but not below the number of shares thereof then outstanding) by the affirmative vote of the holders of a majority in voting power of the stock of the Corporation entitled to vote thereon irrespective of the provisions of Section 242(b)(2) of the DGCL (or any successor provision thereto), and no vote of the holders of any of the Common Stock or the Preferred Stock voting separately as a class shall be required therefor.

This Second Amended and Restated Certificate of Incorporation shall become effective at 5:00 P.M. Eastern Time on the date of the filing of this Second Amended and Restated Certificate of Incorporation in accordance with the DGCL (such time of effectiveness, the “Effective Time”).

The Preferred Stock may be issued from time to time in one or more series, each of which series shall have such distinctive designation or title and such number of shares as shall be fixed by the Board of Directors of the Corporation (the “Board of Directors”) prior to the issuance of any shares thereof. Each such series of Preferred Stock shall have such voting powers, full or limited, or no voting powers, and such preferences and relative, participating optional or other special rights and such qualifications, limitations or restrictions thereof, as shall be stated and expressed in the resolution or resolutions providing for the issue of such series of Preferred Stock as may be adopted from time to time by the Board of Directors prior to the issuance of any shares thereof pursuant to the authority hereby expressly vested in it. The Board of Directors is further authorized to increase or decrease (but not below the number of shares outstanding) the number of shares of any series of Preferred Stock subsequent to the issuance of shares of that series. In case the number of shares of any series shall be so decreased, the shares constituting such decrease shall resume the status of which they had prior to the adoption of the resolution originally fixing the number of shares of such series.

The Common Stock shall have the designations, powers, preferences and relative, participating, optional or other special rights, and the qualifications, limitations or restrictions thereof, as hereinafter set forth in this Article IV.

(a) Dividends. Subject to the preferences applicable to any series of Preferred Stock outstanding at any time, and the terms set forth in this Second Amended and Restated Certificate of Incorporation, the holders of shares of Common Stock shall be entitled to receive such dividends and other distributions in cash, property or shares of stock of the Corporation as may be declared thereon by the Board of Directors from time to time out of assets or funds of the Corporation legally available therefor.

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(b) Liquidation Rights. Upon the dissolution, liquidation or winding up of the Corporation, subject to the rights, if any, of the holders of any outstanding series of Preferred Stock, the holders of shares of Common Stock shall be entitled to receive the assets of the Corporation available for distribution to its stockholders ratably in proportion to the number of shares held by them.

(c) Voting Rights. Except as required by law, each holder of Common Stock shall be entitled, with respect to each share of Common Stock held by such holder on the applicable record date, to one (1) vote in person or by proxy on all matters submitted to a vote of the holders of Common Stock, including, without limitation, in connection with the election of directors to the Board of Directors (it being understood that in respect of the election of directors, no stockholder shall be entitled to cumulate votes on behalf of any candidate), whether voting separately as a class or otherwise. Notwithstanding the foregoing, and except as otherwise required by law, holders of Common Stock, as such, shall not be entitled to vote on any amendment to this Second Amended and Restated Certificate of Incorporation (including any Certificate of Designations relating to any series of Preferred Stock) that relates solely to the terms of one or more outstanding series of Preferred Stock if the holders of such affected series of Preferred Stock are entitled, either separately or together with the holders of one or more other such series of Preferred Stock, to vote thereon pursuant to this Second Amended and Restated Certificate of Incorporation (including any Certificate of Designations relating to any series of Preferred Stock) or pursuant to the DGCL.

ARTICLE V

(a) Management by Board of Directors. The business and affairs of the Corporation shall be managed by or under the direction of the Board of Directors. In addition to the powers and authorities expressly conferred upon the Board of Directors by statute or this Second Amended and Restated Certificate of Incorporation, the Board of Directors may exercise all such powers of the Corporation and do all such lawful acts and things as are not by law, this Second Amended and Restated Certificate of Incorporation or the by-laws required to be exercised or done by the stockholders. Subject to the rights of the holders of any series of Preferred Stock to elect additional directors under specified circumstances, if any, the number of directors of the Corporation shall be fixed from time to time by resolution of the Board of Directors. Elections of directors need not be by written ballot.

(b) Election of Board of Directors. Subject to the rights of the holders of any series of Preferred Stock to elect additional directors under specified circumstances, if any, until the election of directors at the 2015 Annual Meeting of Stockholders, the Board of Directors shall be divided into three classes: Class I, Class II and Class III. The number of directors in each class shall be as nearly equal as possible. The term of the directors in Class III shall expire at the 2015

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Annual Meeting of Stockholders, the term of the directors in Class I shall expire at the 2016 Annual Meeting of Stockholders and the term of the directors in Class II shall expire at the 2017 Annual Meeting of Stockholders. Commencing with the directors elected at the 2015 Annual Meeting of Stockholders, each director elected by the stockholders shall serve for a term expiring at the next succeeding Annual Meeting of Stockholders after their election. Except as the DGCL may otherwise require, in the interim between Annual Meetings of Stockholders or Special Meetings of Stockholders called for the election of directors and/or the removal of one or more directors and the filling of any vacancy in connection therewith, newly created directorships and any vacancies in the Board of Directors, including unfilled vacancies resulting from the removal of directors, may be filled by the vote of a majority of the remaining directors in office, although less than a quorum (as defined in the Corporation’s by-laws), or by the sole remaining director. All directors shall hold office until the expiration of their respective terms of office and until their successors shall have been elected and qualified. A director elected to fill a vacancy resulting from the death, resignation or removal of a director shall serve for the remainder of the full term of the director whose death, resignation or removal shall have created such vacancy and until his or her successor shall have been elected and qualified. Notwithstanding any other provision of this Second Amended and Restated Certificate of Incorporation that might otherwise permit a lesser vote or no vote, but in addition to any affirmative vote of the holders of any particular class or series of the stock of the Corporation required by law or this Second Amended and Restated Certificate of Incorporation, the affirmative vote of the holders of at least 75% of the voting power of the then outstanding voting stock of the Corporation, voting together as a single class, shall be required for the stockholders of the Corporation to alter, amend or repeal this Article V.

(c) Removal of Directors. Prior to and until the time at which the Board of Directors ceases to be classified pursuant to Article V, Section (b) of this Second Amended and Restated Certificate of Incorporation, a director may be removed from office only for Cause (as hereinafter defined) and only by the affirmative vote of the stockholders of the Corporation holding at least a majority of the outstanding stock of the Corporation entitled to vote in an election of directors to the Board of Directors, at meetings of stockholders at which directors are elected, a special meeting of the stockholders or by written consent without a meeting in accordance with the DGCL. For purposes of this Second Amended and Restated Certificate of Incorporation, “Cause” shall mean (x) a final conviction of a felony involving moral turpitude or (y) willful misconduct that is materially and demonstrably injurious economically to the Corporation or its subsidiaries. For purposes of the definition of “Cause,” no act, or failure to act, by a director shall be considered “willful” unless committed in bad faith and without a reasonable belief that the act or failure to act was in the best interest of the Corporation. From and after the time at which the Board of Directors ceases to be classified pursuant to this Article V, Section (b) of this Second Amended and Restated Certificate of Incorporation, any director may be removed, with or without cause, and only by the affirmative vote of the stockholders of the Corporation holding at least a majority of the outstanding stock of the Corporation entitled to vote in an election of directors to the Board of Directors, at meetings of stockholders at which directors are elected, a special meeting of the stockholders or by written consent without a meeting in accordance with the DGCL.

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ARTICLE VI

In furtherance and not in limitation of the powers conferred by statute, the by-laws of the Corporation may be made, altered, amended or repealed by the stockholders of the Corporation or by a majority of the entire Board of Directors; provided, however, that notwithstanding any other provision of this Second Amended and Restated Certificate of Incorporation that might otherwise permit a lesser vote or no vote, but in addition to any affirmative vote of the holders of any particular class or series of the stock of the Corporation required by law or this Second Amended and Restated Certificate of Incorporation, the affirmative vote of the holders of at least 75% of the voting power of the then outstanding voting stock of the Corporation, voting together as a single class, shall be required for the stockholders of the Corporation to alter, amend or repeal Article II, Sections 2, 4 and 12 and Article III, Sections 3, 4 and 5 of the by-laws.

ARTICLE VII

(a) 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.

(b) 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 and 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 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 Court of Chancery or such other court shall deem proper.

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(c) 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 of Directors 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 this Article VII.

(d) The indemnification and other rights set forth in this Article VII shall not be exclusive of any provisions with respect thereto in the by-laws of the Corporation or any other contract or agreement between the Corporation and any officer, director, employee or agent of the Corporation. The Corporation shall have the power to purchase and maintain insurance 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 VII and applicable law, including the DGCL.

(e) Neither the amendment nor repeal of this Article VII, nor the adoption of any provision of this Second Amended and Restated Certificate of Incorporation inconsistent with this Article VII, shall eliminate or reduce the effect of this Article VII 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 VII if such provision had not been so amended or repealed or if a provision inconsistent therewith had not been so adopted.

(f) 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.

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ARTICLE VIII

The Corporation reserves the right to amend this Second Amended and Restated Certificate of Incorporation in any manner permitted by the DGCL and, subject to the terms of this Second Amended and Restated Certificate of Incorporation, all rights and powers conferred herein on stockholders, directors, officers and other persons, if any, are subject to this reserved power.

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IN WITNESS WHEREOF, TransDigm Group Incorporated has caused this Second Amended and Restated Certificate of Incorporation to be signed by Halle Fine Terrion, its General Counsel and Chief Compliance Officer, this 28 day of April, 2014.

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