THIRD SUPPLEMENTAL INDENTURE Dated as of March 31, 2017 to Indenture Dated as of June 9, 2016 by and among TRANSDIGM INC., TRANSDIGM GROUP INCORPORATED, THE GUARANTORS NAMED THEREIN, AND THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A., as Trustee

Exhibit 4.6

TRANSDIGM INC.,

TRANSDIGM GROUP INCORPORATED,

THE GUARANTORS NAMED HEREIN,

AND

THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A.,

as Trustee

THIRD SUPPLEMENTAL INDENTURE

Dated as of March 31, 2017

to

Indenture

Dated as of June 9, 2016

by and among

TRANSDIGM INC.,

TRANSDIGM GROUP INCORPORATED,

THE GUARANTORS NAMED THEREIN,

AND

THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A.,

as Trustee

6.375% Senior Subordinated Notes due 2026

of TransDigm Inc.

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This THIRD SUPPLEMENTAL INDENTURE (this “Supplemental Indenture”), dated as of
March 31, 2017, is entered into by and among XXXXXXX Safety Products LLC, a Delaware limited liability company (“XXXXXXX”), Interiors In Flight LLC, a Delaware limited liability company (together with XXXXXXX, the “Guaranteeing Subsidiaries”), TransDigm Inc., a Delaware corporation (the “Company”), TransDigm Group Incorporated, a Delaware corporation (“TD Group”), Xxxxx Rite Aerospace, Inc., a California corporation (“Xxxxx Rite”), MarathonNorco Aerospace, Inc., a Delaware corporation (“Marathon”), Champion Aerospace LLC, a Delaware limited liability company (“Champion”), Avionic Instruments LLC, a Delaware limited liability company (“Avionic”), Xxxxxx Aerospace Inc., a Delaware corporation (“Xxxxxx”), CDA InterCorp LLC, a Florida limited liability company (“CDA”), Aviation Technologies, Inc., a Delaware corporation (“ATI”), AvtechTyee, Inc., a Washington corporation (“Avtech”), Transicoil LLC, a Delaware limited liability company (“Transicoil”), AeroControlex Group, Inc., a Delaware corporation (“AeroControlex”), Xxxxx Aerospace Inc., a Delaware corporation (“Xxxxx Aerospace”), CEF Industries, LLC, a Delaware limited liability company (“CEF”), Acme Aerospace, Inc., a Delaware corporation (“Acme”), Xxxxx Aerospace, Inc., a Delaware corporation (“Xxxxx”), Semco Instruments, Inc., a Delaware corporation, (“Semco”), Xxxxxxxx Corporation, a California corporation (“Xxxxxxxx”), XxXxxxxxx Aerospace DE, Inc., a Delaware corporation (“XxXxxxxxx Aerospace DE”), XxXxxxxxx Aerospace Holdings, Inc., a Delaware corporation (“XxXxxxxxx Aerospace Holdings”), XxXxxxxxx Aerospace Investments, Inc., a Delaware corporation (“XxXxxxxxx Aerospace Investments”), XxXxxxxxx Aerospace US LLC, a Delaware limited liability company (“XxXxxxxxx Aerospace US”), Texas Rotronics, Inc., a Texas corporation (“Rotronics”), Electromech Technologies LLC (formerly Western Sky Industries, LLC), a Delaware limited liability company (“Electromech”), Xxxxxxxxx LLC, a Delaware limited liability company (“Xxxxxxxxx”), HARCO LLC (formerly Harco Laboratories, Incorporated), a Connecticut limited liability company (“HARCO”), AmSafe Global Holdings, Inc., a Delaware corporation (“AmSafe Global”), Bridport Holdings, Inc., a Delaware corporation (“Bridport Holdings”), AmSafe, Inc., a Delaware corporation (“AmSafe Inc.”), Shield Restraint Systems, Inc. (formerly AmSafe Commercial Products, Inc.), a Delaware corporation (“Shield”), Bridport-Air Carrier, Inc., a Washington corporation (“Bridport-Air”), Bridport Erie Aviation, Inc., a Delaware corporation (“Bridport Erie”), Arkwin Industries, Inc., a New York corporation (“Arkwin”), Whippany Actuation Systems, LLC, a Delaware limited liability company (“Whippany”), Aerosonic LLC, a Delaware limited liability company (“Aerosonic”), Avionics Specialties, Inc., a Virginia corporation (“Avionics Specialties”), Airborne Global, Inc., a Delaware corporation (“Airborne Global”), Airborne Holdings, Inc., a Delaware Corporation (“Airborne Holdings”), Airborne Acquisition, Inc., a Delaware corporation (“Airborne Acquisitions”), Airborne Systems NA Inc., a Delaware corporation (“Airborne Systems NA”), Airborne Systems North America Inc., a Delaware corporation (“Airborne Systems North America”), Airborne Systems North America of CA Inc., a Delaware corporation (“Airborne Systems North America CA”), Airborne Systems North America of NJ Inc., a New Jersey corporation (“Airborne Systems North America NJ”), Telair US LLC, a Delaware limited liability company (“Telair US”), Telair International LLC, a Delaware limited liability company (“Telair International”), Pexco Aerospace, Inc., a Delaware corporation (“Pexco Aerospace”), PneuDraulics, Inc., a California corporation (“PneuDraulics”), Breeze-Eastern LLC, a Delaware limited liability company (“Breeze-Eastern”), ILC Holdings, Inc., a Delaware corporation (“ILC Holdings”), ILC Industries, LLC, a Delaware limited liability company (“ILC Industries”), Data Device Corporation, a Delaware corporation (“DDC”), Beta Transformer Technology Corporation, a New York corporation (“Beta Corporation”), Beta Transformer Technology LLC, a Delaware limited liability company (“Beta LLC”), Young & Franklin Inc., a New York corporation (“Young & Franklin”), Tactair Fluid Controls, Inc., a New York corporation (“Tactair”), and Xxxxxxx Liverpool LLC, a Delaware limited liability company (collectively with TD Group, Xxxxx Rite, Marathon, Champion, Avionic, Xxxxxx, CDA, ATI, Avtech, Transicoil, AeroControlex, Xxxxx Aerospace, CEF, Acme, Xxxxx, Semco, Xxxxxxxx, XxXxxxxxx Aerospace DE, XxXxxxxxx Aerospace Holdings, XxXxxxxxx Aerospace Investments, XxXxxxxxx Aerospace US, Rotronics, Electromech, Schneller, HARCO, AmSafe Global, Bridport Holdings, AmSafe Inc., Shield, Bridport-Air, Bridport Erie, Arkwin, Whippany, Aerosonic, Avionics Specialties, Airborne Global, Airborne Holdings, Airborne Acquisitions, Airborne Systems NA, Airborne Systems North America, Airborne Systems North America CA, Airborne Systems North America NJ, Telair US, Telair International, Pexco Aerospace, PneuDraulics, Breeze-Eastern, ILC Holdings, ILC Industries, DDC, Beta Corporation, Beta LLC, Young & Franklin and Tactair, the “Existing Guarantors”), and The Bank of New York Mellon Trust Company, N.A., as trustee (the “Trustee”) under the Indenture referred to below. Capitalized terms used herein and not otherwise defined shall have the meaning assigned to them in the Indenture.

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WITNESSETH:

WHEREAS, the Company and the Existing Guarantors have heretofore executed and delivered to the Trustee an indenture, dated as of June 9, 2016 (as supplemented by the First Supplemental Indenture thereto, dated as of July 8, 2016, and the Second Supplemental Indenture thereto, dated as of October 28, 2016, the “Indenture”), providing for the issuance by the Company of 6.375% Senior Subordinated Notes due 2026 (the “Notes”) and the guarantees thereof by each of the Existing Guarantors;

WHEREAS, the Indenture provides that under certain circumstances described therein, newly created or acquired Domestic Restricted Subsidiaries shall execute and deliver to the Trustee a supplemental indenture to the Indenture providing for a senior subordinated guarantee of payment of the Notes by such Domestic Restricted Subsidiary (the “Guarantee”);

WHEREAS, all things necessary to make this Supplemental Indenture the legal, valid and binding obligation of the Company, the Existing Guarantors and the Guaranteeing Subsidiaries have been done; and

WHEREAS, pursuant to Section 9.01(g) of the Indenture, the Trustee is authorized to execute and deliver this Supplemental Indenture without the consent of the Holders of the Notes.

NOW, THEREFORE, in consideration of the foregoing and for other good and valuable consideration, the receipt of which is hereby acknowledged, each of the Guaranteeing Subsidiaries covenants and agrees for the equal and ratable benefit of the Holders of the Notes as follows:

1. CAPITALIZED TERMS. Capitalized terms used herein without definition shall have the meanings assigned to them in the Indenture.

2. GUARANTEE, ETC. Each of the Guaranteeing Subsidiaries hereby agrees that from and after the date hereof it shall be a Guarantor under the Indenture and be bound by the terms thereof applicable to Guarantors and shall be entitled to all of the rights and subject to all the obligations of a Guarantor thereunder.

3. RATIFICATION OF INDENTURE; SUPPLEMENTAL INDENTURE PART OF INDENTURE. The Indenture is in all respects ratified and confirmed and all the terms, conditions and provisions thereof shall remain in full force and effect. This Supplemental Indenture shall form a part of the Indenture for all purposes, and every holder of Notes heretofore or hereafter authenticated and delivered shall be bound hereby.

4. EXECUTION AND DELIVERY. Each of the Guaranteeing Subsidiaries agrees that the Guarantee granted by it pursuant to the terms hereof shall remain in full force and effect notwithstanding any failure to endorse on each Note a notation of such Guarantee.

5. NO RECOURSE AGAINST OTHERS. No past, present or future director, officer, employee, incorporator, stockholder or agent of any of the Guaranteeing Subsidiaries (or any successor entity) (other than the Company or the Existing Guarantors), as such, shall have any liability for any obligations of the Company, TD Group, the Guaranteeing Subsidiaries or any other Guarantor under the Notes, any Guarantee, the Indenture or this Supplemental Indenture or for any claim based on, in respect of, or by reason of, such obligations or their creation. Each Holder of the Notes by accepting a Note waives and releases all such liability. The waiver and release are part of the consideration for issuance of the Notes.

6. NEW YORK LAW TO GOVERN. THE INTERNAL LAW OF THE STATE OF NEW YORK SHALL GOVERN AND BE USED TO CONSTRUE THIS SUPPLEMENTAL INDENTURE AND THE GUARANTEE GRANTED HEREUNDER WITHOUT GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY.

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7. COUNTERPART ORIGINALS. The parties may sign any number of copies of this Supplemental Indenture. Each signed copy shall be an original, but all of them together represent the same agreement.

8. EFFECT OF HEADINGS. The Section headings have been inserted for convenience of reference only, are not to be considered part of this Supplemental Indenture and shall in no way modify or restrict any of the terms or provisions hereof.

9. THE TRUSTEE. The Trustee shall not be responsible in any manner whatsoever for or in respect of the validity or sufficiency of this Supplemental Indenture or for or in respect of the recitals contained herein, all of which recitals are made solely by the Guaranteeing Subsidiaries, the Existing Guarantors and the Company.

[Signature page follows.]

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IN WITNESS WHEREOF, the parties hereto have caused this Supplemental Indenture to be duly executed as of the date hereof.

XXXXXXX SAFETY PRODUCTS LLC

INTERIORS IN FLIGHT LLC

By:    /s/ Xxxxxxxx X. Xxxxxxx    

Name: Xxxxxxxx X. Xxxxxxx

Title: Chief Executive Officer

TRANSDIGM INC.

By:    /s/ Xxxxxxxx X. Xxxxxxx    

Name: Xxxxxxxx X. Xxxxxxx

Title: Executive Vice President and
Chief Financial Officer

TRANSDIGM GROUP INCORPORATED

By:    /s/ Xxxxxxxx X. Xxxxxxx    

Name: Xxxxxxxx X. Xxxxxxx

Title Executive Vice President,
Chief Financial Officer and Treasurer

ACME AEROSPACE, INC.

XXXXX RITE AEROSPACE, INC.

AIRBORNE SYSTEMS NORTH AMERICA OF NJ INC.

AMSAFE GLOBAL HOLDINGS, INC.

AMSAFE, INC.

ARKWIN INDUSTRIES, INC.

AVTECHTYEE, INC.

BETA TRANSFORMER TECHNOLOGY CORPORATION

BETA TRANSFORMER TECHNOLOGY LLC

By: Beta Transformer Technology Corporation, as its sole member

XXXXX AEROSPACE, INC.

DATA DEVICE CORPORATION

XXXXX AEROSPACE, INC.

ELECTROMECH TECHNOLOGIES LLC

By: XxXxxxxxx Aerospace Investments, Inc., as its sole member

XXXXXXXX CORPORATION

XXXXXXX LIVERPOOL LLC

By: Young & Franklin Inc., as its sole member

MARATHONNORCO AEROSPACE INC.

XXXXXXXXX AEROSPACE INVESTMENTS, INC.

PEXCO AEROSPACE, INC.

PNEUDRAULICS, INC.

SEMCO INSTRUMENTS, INC.

SHIELD RESTRAINT SYSTEMS, INC.

XXXXXX AEROSPACE INC.

TACTAIR FLUID CONTROLS, INC.

TEXAS ROTRONICS, INC.

YOUNG & FRANKLIN INC.

By:    /s/ Xxxxxxxx X. Xxxxxxx    

Name: Xxxxxxxx X. Xxxxxxx

Title: Chief Executive Officer

[Signature page to the Third Supplemental Indenture – 2026 Notes]

AEROCONTROLEX GROUP, INC.

AIRBORNE ACQUISITION, INC.

AIRBORNE GLOBAL, INC.

AIRBORNE HOLDINGS, INC.

AVIATION TECHNOLOGIES, INC.

BRIDPORT-AIR CARRIER, INC.

BRIDPORT HOLDINGS, INC.

XXXXXXXXX AEROSPACE DE, INC.

XXXXXXXXX AEROSPACE US LLC

By: XxXxxxxxx Aerospace DE, Inc., as its sole member

TRANSICOIL LLC

By: Aviation Technologies, Inc., as its sole member

By:    /s/ Xxxxxxxx X. Xxxxxxx    

Name: Xxxxxxxx X. Xxxxxxx

Title: President and Chief Executive Officer

AEROSONIC LLC

AVIONIC INSTRUMENTS LLC

BREEZE-EASTERN LLC

CDA INTERCORP LLC

CEF INDUSTRIES, LLC

CHAMPION AEROSPACE LLC

HARCO LLC

XXXXXXXXX LLC

TELAIR US LLC

TELAIR INTERNATIONAL LLC

By: Telair US LLC, as its sole member

WHIPPANY ACTUATION SYSTEMS, LLC

Each By: TransDigm Inc., as its sole member

By:    /s/ Xxxxxxxx X. Xxxxxxx    

Name: Xxxxxxxx X. Xxxxxxx

Title: Executive Vice President and
Chief Financial Officer

AIRBORNE SYSTEMS NA INC.

AIRBORNE SYSTEMS NORTH AMERICA INC.

AVIONICS SPECIALTIES, INC.

ILC HOLDINGS, INC.

ILC INDUSTRIES, LLC

By: ILC Holdings, Inc., as its sole member

XXXXXXXXX AEROSPACE HOLDINGS, INC.

By:    /s/ Xxxxxxxx X. Xxxxxxx    

Name: Xxxxxxxx X. Xxxxxxx

Title: President

BRIDPORT ERIE AVIATION, INC.

By:    /s/ Xxxxxxxx X. Xxxxxxx    

Name: Xxxxxxxx X. Xxxxxxx

Title: Vice President and Treasurer

[Signature page to the Third Supplemental Indenture – 2026 Notes]

AIRBORNE SYSTEMS NORTH AMERICA OF CA INC.

By:    /s/ Xxxxx X. Xxxxxxx    

Name: Xxxxx X. Xxxxxxx

Title: Secretary

[Signature page to the Third Supplemental Indenture – 2026 Notes]

THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A., AS TRUSTEE

By:        /s/ Xxxxxxxx X. Xxxxx    

Name: Xxxxxxxx X. Xxxxx

Title: Vice President

[Signature page to the Third Supplemental Indenture – 2026 Notes]