Exhibit 10.1

EXECUTION VERSION

AMENDMENT NO. 2 dated as of March 6, 2017 (this “ Amendment ”), to the SECOND AMENDED AND RESTATED CREDIT AGREEMENT dated as of June 4, 2014 (as amended by Amendment No. 1 dated as of June 9, 2016, and as further amended, supplemented or otherwise modified from time to time prior to the date hereof, the “ Credit Agreement ”; and as amended hereby, the “ Amended Credit Agreement ”), among TRANSDIGM INC., a Delaware corporation (the “ Borrower ”), TRANSDIGM GROUP INCORPORATED, a Delaware corporation (“ Holdings ”), each subsidiary of the Borrower from time to time party thereto, the lenders party thereto (the “ Lenders ”), and CREDIT SUISSE AG, as administrative agent and collateral agent for the Lenders (in such capacities, the “ Agent ”).

A. The Borrower has requested that, (i) on the Amendment No. 2 Effective Date (as defined below), certain provisions of the Credit Agreement be amended as set forth herein and (ii) Mortgages on certain Mortgaged Properties with an individual fair market value on the Amendment No. 2 Effective Date of less than $5,000,000 be released as set forth herein.

B. The Lenders party hereto, constituting the Required Lenders, are willing to amend the Credit Agreement as provided for herein and to authorize the release of such Mortgages as provided for herein, in each case, on the terms and subject to the conditions set forth herein and in the Credit Agreement.

Accordingly, in consideration of the mutual agreements herein contained and other good and valuable consideration, the sufficiency and receipt of which are hereby acknowledged, the parties hereto agree as follows:

SECTION 1. Defined Terms. Capitalized terms used but not defined herein (including in the recitals hereto) shall have the meanings given to them in the Credit Agreement. The rules of interpretation set forth in Section 1.03 of the Credit Agreement are hereby incorporated by reference herein, mutatis mutandis . As used herein, the term “ Amendment No.  2 Transactions ” means, collectively, (a) the execution, delivery and performance by each Loan Party of this Amendment and (b) the payment of fees and expenses incurred in connection with the foregoing.

SECTION 2. Amendments to the Credit Agreement. Effective as of the Amendment No. 2 Effective Date, the Credit Agreement is hereby amended as follows:

(a) Section 1.01 of the Credit Agreement is hereby amended by inserting the following defined terms in the appropriate alphabetical order therein:

“ Amendment No.  2 ” means Amendment No. 2 dated as of March 6, 2017, relating to this Agreement.

“ Amendment No.  2 Effective Date ” has the meaning assigned to such term in Amendment No. 2.

(b) The definition of the term “Permitted Investments” set forth in Section 1.01 of the Credit Agreement is hereby amended by replacing the words “(A) $50,000,000 and (B) 4.0%” in clause (10) thereof with the words “(A) $400,000,000 and (B) 8.0%”.

(c) Clause (10) of Section 6.02(c) of the Credit Agreement is hereby restated in its entirety as follows:

(10) Restricted Payments made on or after the Amendment No. 2 Effective Date in an aggregate amount not to exceed $1,500,000,000, solely to the extent the proceeds thereof are used by Holdings to repurchase shares of its Capital Stock or to pay dividends or other distributions on or in respect of its Capital Stock; provided that (i) any such Restricted Payment is declared and paid or otherwise consummated on or prior to the first anniversary of the Amendment No. 2 Effective Date and (ii) at the time any such Restricted Payment is declared and paid or otherwise consummated and after giving pro forma effect thereto, (A) no Revolving Loans or Swingline Loans are outstanding, (B) if the proceeds thereof are to be used by Holdings to repurchase shares of its Capital Stock, the Borrower’s Consolidated Secured Net Debt Ratio does not exceed 4.00 to 1.00 and (C) if the proceeds thereof are to be used by Holdings to pay dividends or other distributions on or in respect of its Capital Stock, the Borrower’s Consolidated Net Leverage Ratio does not exceed 6.50 to 1.00; provided , further that, subject to compliance with the immediately preceding clause (ii) (but not clause (i)), an amount not to exceed $500,000,000 may be made at any time after the Amendment No. 2 Effective Date (including after the first anniversary of the Amendment No. 2 Effective Date) solely to the extent that the proceeds thereof are used by Holdings to repurchase shares of its Common Stock; provided , further , that on each date that any such Restricted Payment is made pursuant to this clause (10), Holdings and the Borrower shall be deemed to have made the representation and warranty set forth in Section 3.13(a) (with the words “Second Restatement Date” in each place set forth therein being deemed to refer to the date on which such Restricted Payment is made, the words “Second Restatement Transactions” therein being deemed to refer to such Restricted Payment and the parenthetical set forth therein being disregarded) on and as of such date.

SECTION 3. Authorization to Release Certain Mortgages. Effective as of the Amendment No. 2 Effective Date, the Required Lenders hereby authorize and direct the Agent to release any Mortgages with respect to the following Mortgaged Properties (the “ Released Properties ”):

(a) 1043 North 47th Ave., Phoenix, AZ 85043-1817

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(b) 8301 Imperial Drive, Waco, TX 76712

(c) 900 South Richfield Road, Placentia, CA 92870

(d) 5000 Triggs Street, Los Angeles, CA 90022

(e) 313 Gillett Street, Painesville, OH 44077

(f) 450 Goolsby Blvd., Deerfield, FL 33442

(g) 2600 South Custer Ave., Wichita, KS 67217

(h) 1414 Randolph Avenue, Avenel, NJ 07001

(i) 4223 Monticello Blvd., South Euclid, OH 44121; and

(j) 9810 6th Street, Rancho Cucamonga, CA 91730.

SECTION 4. Conditions Precedent to Effectiveness. The effectiveness of this Amendment shall be subject to the satisfaction or waiver of the following conditions precedent (the date on which such conditions precedent are so satisfied or waived, the “ Amendment No.  2 Effective Date ”):

(a) the Agent shall have received counterparts of this Amendment that, when taken together, bear the signatures of (i) the Borrower, Holdings and the Subsidiaries of the Borrower party to the Credit Agreement on the date hereof, (ii) the Agent and (iii) Lenders constituting the Required Lenders;

(b) at the time of and immediately after giving effect to this Amendment, each of the conditions set forth in Section 4.01(b) and Section 4.01(c) of the Credit Agreement shall be satisfied; provided that, for purposes of the condition set forth in Section 4.01(b), the words “Second Restatement Date” set forth in Section 3.13(a) of the Credit Agreement shall be deemed to be “Amendment No. 2 Effective Date” in each place they appear therein, the words “Second Restatement Transactions” in Section 3.13(a) of the Credit Agreement shall be deemed to refer to the Amendment No. 2 Transactions, and the parenthetical in Section 3.13(a) of the Credit Agreement shall be disregarded;

(c) the Agent shall have received a certificate dated as of the Amendment No. 2 Effective Date and executed by a Financial Officer of the Borrower with respect to the conditions set forth in paragraph (b) above; and

(d) the Agent shall have received (x) payment of the fees set forth in Section 5 hereof and (y) payment of all fees and reimbursement of all expenses separately agreed in writing by the Borrower and the Agent or required by Section 9.03 of the Credit Agreement or by any other Loan Document to be reimbursed by the Borrower on the Amendment No. 2 Effective Date in connection with this Amendment and the transactions contemplated hereby to the

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extent such expenses are invoiced at least one Business Day prior to the Amendment No. 2 Effective Date.

The Agent shall notify the Borrower and the Lenders of the Amendment No. 2 Effective Date, and such notice shall be conclusive and binding.

SECTION 5. Fees . On the Amendment No. 2 Effective Date, the Borrower shall pay to the Agent for the account of each Lender that executes and irrevocably delivers a signature page to this Amendment to the Agent (or its counsel) at or prior to 12:00 (noon), New York City time, on March 2, 2017, a fee (the “ Amendment Fees ”), in an amount equal to 0.15% of the aggregate amount of Revolving Credit Commitments (whether used or unused) and outstanding Term Loans of such Lender on the Amendment No. 2 Effective Date. The Amendment Fees shall be payable in immediately available funds and, once paid, shall not be refundable under any circumstances.

SECTION 6. Representations and Warranties. To induce the other parties hereto to enter into this Amendment, Holdings and the Borrower represent and warrant to each of the Lenders and the Agent that (a) this Amendment has been duly authorized, executed and delivered by Holdings, the Borrower and the Subsidiaries of the Borrower party hereto, and this Amendment constitutes a legal, valid and binding obligation of Holdings, the Borrower and the Subsidiaries of the Borrower party hereto, subject to applicable bankruptcy, insolvency, moratorium, reorganization, fraudulent conveyance or other similar laws affecting creditors’ rights generally and to general principles of equity; (b) after giving effect to this Amendment, the representations and warranties set forth in Article III of the Credit Agreement and in each other Loan Document are true and correct in all material respects on and as of the Amendment No. 2 Effective Date, except to the extent such representations and warranties expressly relate to an earlier date, in which case they were true and correct in all material respects on and as of such earlier date; provided that, (i) in each case, such materiality qualifier shall not be applicable to any representation and warranty that already is qualified or modified by materiality in the text thereof and (ii) for purposes of the representation in Section 3.13(a) of the Credit Agreement, the words “Second Restatement Date” in each place set forth therein shall be deemed to be “Amendment No. 2 Effective Date”, the words “Second Restatement Transactions” shall be deemed to refer to the Amendment No. 2 Transactions and the parenthetical in Section 3.13(a) of the Credit Agreement shall be disregarded and (c) as of the Amendment No. 2 Effective Date, after giving effect to this Amendment, no Default or Event of Default has occurred and is continuing.

SECTION 7. Effect of Amendment. Except as expressly set forth herein, this Amendment shall not by implication or otherwise limit, impair, constitute a waiver of, or otherwise affect the rights and remedies of the Lenders or the Agent under the Credit Agreement or any other Loan Document, and shall not alter, modify, amend or in any way affect any of the terms, conditions, obligations, covenants or agreements contained in the Credit Agreement or any other Loan Document, all of which are ratified and affirmed in all respects and shall continue in full force and effect. Nothing herein shall be deemed to entitle any Loan Party to a consent to, or a waiver, amendment,

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modification or other change of, any of the terms, conditions, obligations, covenants or agreements contained in the Credit Agreement or any other Loan Document in similar or different circumstances. This Amendment shall apply and be effective only with respect to the provisions of the Credit Agreement specifically referred to herein. After the Amendment No. 2 Effective Date, any reference to the Credit Agreement in any Loan Document, and the terms “this Agreement”, “herein”, “hereunder”, “hereto”, “hereof” and words of similar import in the Credit Agreement, shall, unless the context otherwise requires, mean the Credit Agreement as modified hereby. This Amendment shall constitute a “Loan Document” for all purposes of the Amended Credit Agreement and the other Loan Documents.

SECTION 8. Acknowledgement and Consent. Each Loan Party hereby acknowledges that it has read this Amendment and consents to the terms hereof and further hereby affirms, confirms and agrees that (a) notwithstanding the effectiveness of this Amendment, the obligations of such Loan Party under each of the Loan Documents to which it is a party shall not be impaired and each of the Loan Documents to which such Loan Party is a party is, and shall continue to be, in full force and effect and is hereby confirmed and ratified in all respects, in each case, as amended hereby; (b) its Guarantee of the Obligations, and the pledge of and/or grant of a security interest in its assets as Collateral to secure the Obligations, all as and to the extent provided in the Collateral Documents as originally executed, shall continue in full force and effect in respect of, and to secure, the Obligations; and (c) all the representations and warranties made by or relating to it contained in the Credit Agreement and the other Loan Documents are true and correct in all material respects on and as of the Amendment No. 2 Effective Date, except to the extent such representations and warranties expressly relate to an earlier date, in which case they shall be true and correct in all material respects on and as of such earlier date; provided that, in each case, such materiality qualifier shall not be applicable to any representation and warranty that already is qualified or modified by materiality in the text thereof.

SECTION 9. Counterparts. This Amendment may be executed in counterparts (and by different parties hereto on different counterparts), each of which shall constitute an original, but all of which when taken together shall constitute a single contract. Delivery of an executed counterpart of a signature page of this Amendment by facsimile or other electronic method of transmission shall be effective as delivery of a manually signed counterpart of this Amendment.

SECTION 10. Governing Law. THIS AMENDMENT SHALL BE CONSTRUED IN ACCORDANCE WITH AND GOVERNED BY THE LAWS OF THE STATE OF NEW YORK. The provisions of Sections 9.09 and 9.10 of the Credit Agreement shall apply to this Amendment to the same extent as if fully set forth herein.

SECTION 11. Headings. Section headings used herein are for convenience of reference only, are not part of this Amendment and shall not affect the construction of, or be taken into consideration in interpreting, this Amendment.

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IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be duly executed by their duly authorized officers, all as of the date first above written.

[Signature Page to Amendment No. 2]

[Signature Page to Amendment No. 2]

Name of Institution: 1776 CLO I, Ltd.

For any institution requiring a second signature line:

Name of Institution: 3i GLOBAL FLOATING RATE INCOME LIMITED

For any institution requiring a second signature line:

Name of Institution: 3i US Senior Loan Fund, L.P.

For any institution requiring a second signature line:

Name of Institution: 5180-2 CLO LP

For any institution requiring a second signature line:

Name of Institution: 55 Loan Strategy Fund a series Trust of Multi Manager Global Investment Trust

For any institution requiring a second signature line:

Name of Institution: 55 Loan Strategy Fund Series 2 A Series Trust Of Multi Manager Global Investment Trust

For any institution requiring a second signature line:

Name of Institution: 55 Loan Strategy Fund Series 3 A Series Trust of Multi Manager Global Investment Trust

For any institution requiring a second signature line:

Name of Institution: A Series Trust of Multi Manager Global Investment Trust - PIMCO Cayman Bank Loan Libor Plus Fund JPY Hedge

For any institution requiring a second signature line:

Name of Institution: A Voce CLO, Ltd.

For any institution requiring a second signature line:

Name of Institution: AAA Life Insurance Company

For any institution requiring a second signature line:

Name of Institution: ABR Reinsurance LTD.

For any institution requiring a second signature line:

Name of Institution: ACAS CLO 2012-1, Ltd.

For any institution requiring a second signature line:

Name of Institution: ACAS CLO 2013-1, Ltd.

For any institution requiring a second signature line:

Name of Institution: ACAS CLO 2013-2, LTD

For any institution requiring a second signature line:

Name of Institution: ACAS CLO 2014-1, Ltd.

For any institution requiring a second signature line:

Name of Institution: ACAS CLO 2014-2, Ltd.

For any institution requiring a second signature line:

Name of Institution: ACAS CLO 2015-1, Ltd.

For any institution requiring a second signature line:

Name of Institution: ACAS CLO 2015-2, Ltd.

For any institution requiring a second signature line:

Name of Institution: ACAS CLO IX, Ltd.

For any institution requiring a second signature line:

Name of Institution: ACE American Insurance Company

For any institution requiring a second signature line:

Name of Institution: Ace European Group Limited

For any institution requiring a second signature line:

Name of Institution: ACE Property & Casualty Insurance Company

For any institution requiring a second signature line:

Name of Institution: ACIS CLO 2013-2 LTD

For any institution requiring a second signature line:

Name of Institution: ACIS CLO 2013-1 LTD.

For any institution requiring a second signature line:

Name of Institution: ACIS CLO 2014-3, Ltd.

For any institution requiring a second signature line:

Name of Institution: ACIS CLO 2014-4, Ltd.

For any institution requiring a second signature line:

Name of Institution: ACIS CLO 2014-5, Ltd.

For any institution requiring a second signature line:

Name of Institution: ACIS CLO 2015-6, Ltd

For any institution requiring a second signature line:

Name of Institution: Adams Mill CLO Ltd.

For any institution requiring a second signature line:

Name of Institution: Adirondack Park CLO Ltd.

For any institution requiring a second signature line:

Name of Institution: AdvisorShares Pacific Asset Enhanced Floating Rate ETF

For any institution requiring a second signature line:

Name of Institution: AEGIS Electric and Gas International Services, Ltd.

For any institution requiring a second signature line:

Name of Institution: Affiliated Independent Distributors, Inc.

For any institution requiring a second signature line:

Name of Institution: AGF Floating Rate Income Fund

For any institution requiring a second signature line:

AIB Debt Management, Limited.

Name of Institution: SunAmerica Income Funds - SunAmerica Flexible Credit Fund

For any institution requiring a second signature line:

Name of Institution: Allstate Insurance Company

For any institution requiring a second signature line:

Name of Institution: Allstate Life Insurance Company

For any institution requiring a second signature line:

For any institution requiring a second signature line:

For any institution requiring a second signature line:

Name of Institution: AIRLIE CLO 2006 II Ltd.

For any institution requiring a second signature line:

Name of Institution: ALJ Global Bank Loan Fund 2015 A SERIES TRUST OF MULTI MANAGER GLOBAL INVESTMENT TRUST

For any institution requiring a second signature line:

Name of Institution: ALJ Global Loan Fund 2016 A SERIES TRUST OF MULTI MANAGER GLOBAL INVESTMENT TRUST

For any institution requiring a second signature line:

Name of Institution: AXA IM Inc. for and on behalf of

Allegro CLO II Limited

Allegro CLO III Limited

Name of Institution: AB Bond Fund, Inc. - AB Limited Duration High Income Portfolio

For any institution requiring a second signature line:

Name of Institution: AllianceBernstein Global High Income Fund

For any institution requiring a second signature line:

Name of Institution: AllianceBernstein High Income Fund

For any institution requiring a second signature line:

Name of Institution: AllianceBernstein Institutional Investments - AXA High Yield Loan II Portfolio

For any institution requiring a second signature line:

Name of Institution: AllianceBernstein Institutional Investments - AXA High Yield Loan Portfolio

For any institution requiring a second signature line:

Name of Institution: ALM VII (R), Ltd.

For any institution requiring a second signature line:

Name of Institution: ALM VII (R)-2, Ltd.

For any institution requiring a second signature line:

Name of Institution: ALM VII, Ltd.

For any institution requiring a second signature line:

Name of Institution: ALM VIII, Ltd.

For any institution requiring a second signature line:

Name of Institution: ALM XI, Ltd.

For any institution requiring a second signature line:

Name of Institution: ALM XII, Ltd.

For any institution requiring a second signature line:

Name of Institution: ALM XIV, LTD.

For any institution requiring a second signature line:

Name of Institution: ALM XIX, LTD.

For any institution requiring a second signature line:

Name of Institution: ALM XVI, LTD.

For any institution requiring a second signature line:

Name of Institution: ALM XVII, Ltd.

For any institution requiring a second signature line:

Name of Institution: AMADABLUM US Leveraged Loan Fund a Series Trust of Global Multi Portfolio Investment Trust

For any institution requiring a second signature line:

Name of Institution: American Century Capital Portfolios, Inc. - AC Alternatives Income Fund

For any institution requiring a second signature line:

Name of Institution: American General Life Insurance Company

For any institution requiring a second signature line:

Name of Institution: American Home Assurance Company

For any institution requiring a second signature line:

Name of Institution: American Honda Master Retirement Trust

For any institution requiring a second signature line:

Name of Institution: Ameriprise Certificate Company

For any institution requiring a second signature line:

Name of Institution: AMJ Bank Loan Fund A Series Trust of Multimanager Global Investment Trust

For any institution requiring a second signature line:

Name of Institution: AMJ Bank Loan Fund SERIES 2 A SERIES TRUST OF MULTI MANAGER GLOBAL INVESTMENT TRUST

For any institution requiring a second signature line:

Name of Institution: AMJ LOAN FUND SERIES 3 A SERIES TRUST OF MULTIMANAGER GLOBAL INVESTMENT TRUST

For any institution requiring a second signature line:

Name of Institution: AMMC CLO 15, LIMITED

For any institution requiring a second signature line:

Name of Institution: AMMC CLO 16, LIMITED

For any institution requiring a second signature line:

Name of Institution: AMMC CLO 17, LIMITED

For any institution requiring a second signature line:

Name of Institution: AMMC CLO 18, LIMITED

For any institution requiring a second signature line:

Name of Institution: AMMC CLO 19, LIMITED