# STC ST165CH - Type: Supplemental type certificate - Status: Current, Reissued - Holder: USA Jet Airlines Inc., United States - Description: Fabrication and installation of a Stage 3 hushkit when powered by Pratt & Whitney JT8D-7, -9, or -11, -15, or -17 series engines. - Applied: January 18, 1991 - Status date: August 1, 2008 - Product: Aircraft, Large Multi-Engine - Certification basis: Part 21 - Data sheets: [TCDS A6WE](https://openairdocs.org/tcds/A6WE) - Certificate PDF: https://openairdocs.org/files/sha256/05/98/05981a003ae3f63bd40def36a68865ae72106e6707b9141cb45e58ed1bd65247 - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/AD45484331E976AC8625749D00474FA0.0001 - DRS record last changed: December 5, 2025 - Page: https://openairdocs.org/stc/ST165CH ## ADs that name it (0) None. ## Approved models (8) - McDonnell Douglas Corporation DC-9-31 ([TCDS A6WE](https://openairdocs.org/tcds/A6WE)) - McDonnell Douglas Corporation DC-9-32 ([TCDS A6WE](https://openairdocs.org/tcds/A6WE)) - McDonnell Douglas Corporation DC-9-32F ([TCDS A6WE](https://openairdocs.org/tcds/A6WE)) - McDonnell Douglas Corporation DC-9-33F ([TCDS A6WE](https://openairdocs.org/tcds/A6WE)) - McDonnell Douglas Corporation DC-9-34 ([TCDS A6WE](https://openairdocs.org/tcds/A6WE)) - McDonnell Douglas Corporation DC-9-34F ([TCDS A6WE](https://openairdocs.org/tcds/A6WE)) - McDonnell Douglas Corporation DC-9-41 ([TCDS A6WE](https://openairdocs.org/tcds/A6WE)) - McDonnell Douglas Corporation DC-9-51 ([TCDS A6WE](https://openairdocs.org/tcds/A6WE)) ## What the certificate says Read from the PDF's text layer, without the form's printed wording; the layout is lost and the order can differ. The PDF is the record. United States Of America Department of Transportation - Federal Aviation Administration Certificate issued to replace certificate reported lost Supplemental Type Certificate This Certificate issued to USA JET AIRLINES, INC. HANGAR 2064 D Street Willow Run Airport Belleville, Michigan 48111 Part 4b* of the Civil Air Regulations. *Certification basis is set forth in Type Certificate Data Sheet TCDS No. A6WE Original Product Type Certificate Number : A6WE McDonnell Douglas DC-9-31, -32, -32F, -33F, -34, -34F, DC-9-41, DC-9-51 Description of Type Design Change : Fabrication and installation of Stage 3 Hushkits on the above models when powered by Pratt & Whitney JT8D -7, -9, -11, -15, or -17 series engines in accordance with ABS Partnership Master Dr awing List No. MDL- 009-002-91, Rev. G, dated December 13, 1993, or later FAA approved revisions. Limitations and Conditions: The installation should not be incor porated in any aircraft unless it is determined that the interrelationship between this installation and any previously approved configuration will not introduce any adverse effect upon the airworthiness of the aircraft. The approval of this modification applies to the above noted airplane model series only. A copy of this STC must be included in the permanent records of the modified aircraft. If the holder agrees to permit another person to us e this certificate to alter the product, the holder shall give the other person written evidence of that permission. (See Page 3 for continuation) Date of application : January 18, 1991 Date of issuance : January 26,1994 Date reissued : Mar. 27, 2002; Dec. 24, 2003 August 1, 2008 Date amended : April 29, 1997; April 30, 1999 ( Signature) Manager, Propulsion Branch Los Angeles Aircraft Certification Office ( Title) NOTE: **DO NOT DELETE THIS PAGE.** **DO NOT ADD ANY DATA TO THIS PAGE.** **THIS PAGE IS FOR PAGE NUMBERING PURPOSES, PLEASE DISCARD PRINTED COPY.** Number ST165CH Limitations and Conditions: (Cont.) 1. Compatibility of this design change with pr eviously approved modifications must be determined by the installer. 2. Aircraft Model and eligibly combinations are as follows: Aircraft Model Pratt & Whitney Engine Models DC-9-31, -32, -32F, -33F, -34, -34F JT8D-7, -7A, -9, -9A, -11, -15, -15A, -17, -17A DC-9-41 JT8D-9, -11, -15 DC-9-51 JT8D-15, -15A, -17, -17A 3. FAA approved Airplane Flight Manual S upplement FMS-K51000-093 for McDonnell Douglas DC-9-31, -32, -32F, -33F, -34, -34F series w ith Pratt & Whitney JT8D-7, -9, -11, -15, -17 series engines with ABS Partnership Stage 3 Hushkit installed, dated January 26, 1994, or later FAA approved revision is required with this modification. FAA approved Airplane Flight Manual S upplement FMS-K51001-093 for McDonnell Douglas DC-9-41 series with Pratt & Whitney JT8D-9, -11, -15, series engines with ABS Partnership Stage 3 Hushkit installed, dated January 26, 1994, or late r FAA approved revision is required with this modification. FAA approved Airplane Flight Manual S upplement FMS-K51002-093 for McDonnell Douglas DC-9-51 series with Pratt & Whitney JT8D-15, -17 series engines with ABS Partnership Stage 3 Hushkit installed, Revision A, Dated June 18, 1997, or later FAA approved revision is required with this modification. 4. The instruction for continued airworthiness of the basic aircraft and engines are still applicable. -END- ## Every issue (2) - August 1, 2008: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/05/98/05981a003ae3f63bd40def36a68865ae72106e6707b9141cb45e58ed1bd65247) - December 24, 2003: Reissued, Historical. [certificate](https://openairdocs.org/files/sha256/e8/bb/e8bbc2ec6047b65b30d06865e5c0ddfa5da01e394267ebe89215ed2ce0cc2779) --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.