# STC SA3-571 - Type: Supplemental type certificate - Status: Current, Reissued - Holder: D'Shannon Products Ltd., United States - Description: Lycoming O-360-A1D engine, McCauley 2D36C14/78KM-4 or Hartzell HC-C2YK-1A/7666-2 propellers. - Applied: November 11, 1959 - Status date: July 14, 2011 - Product: Aircraft, Single-Engine - Certification basis: Part 3, Part 21 - Data sheets: [TCDS 3A12](https://openairdocs.org/tcds/3A12) - Certificate PDF: https://openairdocs.org/files/sha256/c3/48/c348ab86aac9ea043f1884a3a2a1ec4306d445b2a5c3c89ce0af9b0bf7046677 - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/920D417C119B7825862578EF00479E41.0001 - DRS record last changed: December 5, 2025 - Page: https://openairdocs.org/stc/SA3-571 ## ADs that name it (2) - [AD 82-07-02](https://openairdocs.org/ad/82-07-02): Engine Crankcase Breather · Lycoming O-360-A1A engine and Hartzell HC-C2YK-1B/7666A-2… (Avcon Industries STC SA1324CE or 14 others). Effective Apr 8, 1982. Named in the applicability - [AD 69-15-03](https://openairdocs.org/ad/69-15-03): Muffler Assembly · Lycoming O-320-A1A, A1B, A3A, A3B or Lycoming O-320-B1A, B1B… (D'Shannon Products STC SA135CE or 8 others). Effective Aug 20, 1969. Named in the applicability ## Approved models (9) - The Cessna Aircraft Company 172 ([TCDS 3A12](https://openairdocs.org/tcds/3A12)) - The Cessna Aircraft Company 172A ([TCDS 3A12](https://openairdocs.org/tcds/3A12)) - The Cessna Aircraft Company 172B ([TCDS 3A12](https://openairdocs.org/tcds/3A12)) - The Cessna Aircraft Company 172C ([TCDS 3A12](https://openairdocs.org/tcds/3A12)) - The Cessna Aircraft Company 172D ([TCDS 3A12](https://openairdocs.org/tcds/3A12)) - The Cessna Aircraft Company 172E ([TCDS 3A12](https://openairdocs.org/tcds/3A12)) - The Cessna Aircraft Company 172F (USAF T-41A) ([TCDS 3A12](https://openairdocs.org/tcds/3A12)) - The Cessna Aircraft Company 172G ([TCDS 3A12](https://openairdocs.org/tcds/3A12)) - The Cessna Aircraft Company 172H (USAF T-41A) ([TCDS 3A12](https://openairdocs.org/tcds/3A12)) ## 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. This certificate issued to Part 3 of the Civil Air Regulations. Installation of Lycoming O-360-A1D engine with standard Lycoming accessories and McCauley 2D26C14/78KM-4 or Hartzell HC- C2YK-1A/7666-2 propellers. Data required: Cessna 172, A, B, C – Doyn Aircraft, Inc. Dwg. Nos. 1199 dtd 11/1/59; 1199-DCN1A dtd 4/18/60; 1199-DCN2 dtd 11/9/60; and 1199-DCN3A dtd 7/1/63. Cessna 172, D, E, F, G, H – Doyn Aircraft, Inc. Dwg. Nos. above for Cessna 172 and 1013—DCN3 dtd 8/22/63; 1700-DCN3 dtd 8/22/63; 1702 dtd 9/8/61; 1703 dtd 9/7/61; 1702-DCN1 dtd 9/4/63; and 1703-DCN2 dtd 8/25/63; in addition for Cessna 172G and H, Dwg. No. 1102-DCN3 dtd 10/28/65. 1. Engine Limits: (All operations) 2700 RPM, 180 HP. 2. Propeller Limits: McCauley 2D36C14/78KM-4 propleller. Pitch setting: 12.7° low, 27.5° high. Hartzell HC-C2YK- 1/7666-2 propeller. Pitch setting 13° low, 29° high. Placard: “Avoid continuous operation between 2000 RPM and 2250 RPM.” Powerplant Instruments: Red Line 2700, Red Arc 2000 – 2250 RPM. Special Installation Procedure: Blade centerline must be 120° clockwise from No. 1 crankthrow facing engine propeller engine. Compatibility of this modification with other previously approved modifications must be determined by the installer. D’Shannon Products, Ltd. 1309 County Road 134 Buffalo, MN 55313 3A12 Make : Cessna Model : 172 A, B, C, D, E, F, G, H Date of application : November 11, 1959 Date of issuance : September 21, 1960 Date reissued : 7/26/61; 7/5/63; 9/4/63; 10/23/63; 4/30/65; 11/5/65; 1/25/66; 12/20/66; 5/17/78; 5/12/11; 7/14/11 ( Signature) Melvin D. Taylor Manager Atlanta Aircraft Certification Office ( Title) ## Every issue (2) - July 14, 2011: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/c3/48/c348ab86aac9ea043f1884a3a2a1ec4306d445b2a5c3c89ce0af9b0bf7046677) - May 12, 2011: Reissued, Historical. [certificate](https://openairdocs.org/files/sha256/5e/38/5e38d420b9f8fec4d2672e9520d02c123dcfc5710bea32cee14176d36324d2b9) --- 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.