# STC SA09021AC-D

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: S-TEC Corporation, United States
- Description: Installation of S-TEC yaw damper system, Model ST-602.
- Applied: September 4, 1995
- Status date: September 21, 1995
- Product: Aircraft, Small Multi-Engine
- Certification basis: Part 21
- Data sheets: [TCDS A8EA](https://openairdocs.org/tcds/A8EA)
- Certificate PDF: https://openairdocs.org/files/sha256/e3/05/e305f1e3fce1563a5304cb1fcb1756469dac3ae66ea574a854a155302374d9c0
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/77C146A677D4E15385256CC1007F39AA.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA09021AC-D

## ADs that name it (0)

None.

## Approved models (1)

- Piper Aircraft Inc. PA-31P ([TCDS A8EA](https://openairdocs.org/tcds/A8EA))

## What the certificate says

This is OCR from the scanned FAA certificate. OCR can misread letters and numbers.

Baited Scares of Saerica Department of Transportation Federal Aviation Administration Supplemental Type Certificate Number: SA09021AC-D This certificate issued to: S-TEC Corporation 946 Pegram Mineral Wells, TX 76067 Certifies that the change in the type design for the follwing product with the limitations and conditions Shovefor as specified horeon mects the sinvorthiness reguinements of Port 3 of the CIVIl Air Regulations Original Product -Type Contificato Numbon: ABEA Make: Piper Model: PA-31P Tusciplion of Type Design hangs:

Installation of S-TEC Yaw Damper System, Model ST-602, according to Bulletin No.

/02, dated 9-01-95 and Master Drawing List No. 92804, dated 9-01-95 or later FAA Approved revisions of the above data (28 Volt System).

1. FAA/DAS Approved Pilot's Operating Handbook and/or Airplane Flight Manual Supplement, P/N 891196, dated 9-21-95 is required for Piper Model PA-31P or later FAA Approved revisions of the above supplement.

2. Compatibility of this modification with other previously approved modifications must be determined by the installer.

Thomas DAS Staff Coordinator, DAS 5 SW (Title)

FAA Foss 8110-2 (10-68)

TRANSFER ENDORSEMENT Transfer the ownership of Supplemental Type Certificate Number to (Name of transferee) (Address of transferee) (Number and street) (CItY, State, and ZIP code) from (Name of grantor) (Print or type) (Address of grantor) (Number & street) (City, Stater and ZIP code) Extent of Authority (if licensing agreement):

Signature of grantor (In ink):

## Every issue (1)

- September 21, 1995: Issued, Current. [certificate](https://openairdocs.org/files/sha256/e3/05/e305f1e3fce1563a5304cb1fcb1756469dac3ae66ea574a854a155302374d9c0)

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