# STC SA7789SW-D

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: S-TEC Corporation, United States
- Description: Installation of S-TEC system60 two axis automatic flight guidance system, model ST-305, with optional automatic electric trim system.
- Applied: January 21, 1991
- Status date: February 14, 1991
- Product: Aircraft, Single-Engine
- Certification basis: Part 21
- Data sheets: [TCDS 2A13](https://openairdocs.org/tcds/2A13)
- Certificate PDF: https://openairdocs.org/files/sha256/2f/38/2f380077efd5116cbbe2a1d477e4b0b454fde6f1935863a2c3a403b2b838618c
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/9A324E7443C3AAD185256CC20056A491.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA7789SW-D

## ADs that name it (0)

None.

## Approved models (1)

- The New Piper Aircraft Inc. PA-28-235 ([TCDS 2A13](https://openairdocs.org/tcds/2A13))

## What the certificate says

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

Writed Scates of Saurice Department of Transportation Federal Aviation Administration Supplemental Type Certificate Number: SA778954-0 This certificate issued to: S-TEC Corporation Rt. 4, Bldg. 946 Wolters Industrial Complex Mineral Wells, TX 76067 Certifies that the change in the type design for the following product with the limilations and conditions shomfor as specified horon meels the sinconthiness requinments of Port 3 of the CIVil Air Regulations Original Product -Typo Contificato Numbon: 2A13 Make: PIPER Model: PA-28-235 Description of Type Design Change:

Installation of S-TEC System 60 Two Axis Automatic Flight Guidance System, Model ST-305, with Optional Automatic Electric Trim System according to Bulletin No. 405, dated 1-18-91 and Master Drawing List No. 92533, dated 1-18-91 with Optional Flight Director Steering Horizon and/or later FAA Approved revisions of the above data (14 Volt System).

1. Eligible only on Piper Model PA-28-235, S/N 28-7310001 & Up.

L. FAA/DAS Approved Airplane Flight Manual Supplement, P/N 89908, dated 2-14-91 1s required for Piper Model PA-28-235, S/N 28-7310001 & Up and/or later FAA Approved revisions of the above supplement.

3. Compatibility of this modification with other previously approved modifications This come ale ne termy po in thale in e2 the basis for approved shall romain in ofel until sur vendored, suspended, revoked, or a lormination dato is dhorviss established by the SAdministrator of the Federal Aviation Administration Date of Application: 1-21-91 Datomissuso:

Diato sissnanco: 2-14-91 Date Amended:

FEDERAL ANTATION By Direction of the Administrator Winian ( Signajes William J. Thomas DAS Staff Coordinator, DAS 5 SW (Title)

17.

**PAA 7026 8110-2 (10-68)**

TRANSFER ENDORSEMENT Transfer the ownership of Supplemental Type Certificate Number - to (Name of transferee) (Address of transferee) (Number and streel) (City, Stale, and ZIP code) from (Name of grantor) (Print or type) (Address of grantor) ( Nunher and streel) ( City. State, and ZIP code ) Extent of Authority (if licensing agreement):

Date of Transfer: - Signature of grantor (In ink):

## Every issue (1)

- February 14, 1991: Issued, Current. [certificate](https://openairdocs.org/files/sha256/2f/38/2f380077efd5116cbbe2a1d477e4b0b454fde6f1935863a2c3a403b2b838618c)

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