# STC SA09016AC-D

- Type: Supplemental type certificate
- Status: Current, Amended
- Holder: S-TEC Corporation, United States
- Description: Installation of S-TEC System 55/55X two axis automatic flight guidance system, Model ST-594
- Applied: July 24, 1995
- Status date: May 11, 2001
- Product: Aircraft, Small Multi-Engine
- Certification basis: Part 21
- Data sheets: [TCDS 3A25](https://openairdocs.org/tcds/3A25)
- Certificate PDF: https://openairdocs.org/files/sha256/e3/51/e351303dfac2a33dceeed5623db11afa9e2f26c685125e8f9ce36689c031e69f
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/6D3A6FBE4B489F0085256CC1007F39A4.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA09016AC-D

## ADs that name it (0)

None.

## Approved models (5)

- Cessna Aircraft Company 320B ([TCDS 3A25](https://openairdocs.org/tcds/3A25))
- Cessna Aircraft Company 320C ([TCDS 3A25](https://openairdocs.org/tcds/3A25))
- Cessna Aircraft Company 320D ([TCDS 3A25](https://openairdocs.org/tcds/3A25))
- Cessna Aircraft Company 320E ([TCDS 3A25](https://openairdocs.org/tcds/3A25))
- Cessna Aircraft Company 320F ([TCDS 3A25](https://openairdocs.org/tcds/3A25))

## What the certificate says

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

United States of America Department of Transportation Federal Aviation Administration Supplemental Type Certificate Number: SA09016AC-D This certificate issued to: S-TEC Corporation One S-TEC Way Mineral Wells Municipal Airport Mineral Wells, TX 76067-9236 Lost 3 of the Cil st i Kegulations.

Original Product I ype Certificate A umber : ЗА25 Make: Cessna Model: 320B, 320C, 320D, 320E, and 320F Description of Type Design Change:

Installation of S-TEC System 55/55X Two Axis Automatic Flight Guidance System, Model ST-594, according to Bulletin No. 694, Revision 4, dated 5-11-01 and Master Drawing List No. 92794, Revision D, dated 5-11-01 or later FAA Approved revisions of the above data (28 Volt System).

(See Continuation Sheet, Page 2, a part of this STC.)

If the holder agrees to permit another person to use this certificate to alter the product, the holder shall give the other person written evidence of that permission.

Date of Application: 7-24-95 Bate wisued:

Date of Issuance: 8-02-95 Date Amended: 5-11-01 By Direction of the Administrator FEDERAL AVIATION тілк (Signature) TOMNISTRATIO Michael Keirnan DAS Staff Coordinator, DAS 5 SW (Title)

United States of America Department of Transportation Federal Aviation Administration Supplemental Type Certificate (Continuation Sheet) Number: SA09016AC-D Limitations and Conditions: (con't.)

FAA/DAS Approved Supplemental Flight Manual, P/N 891181, dated 8-02-95 is required for Cessna Models 320B, 320C, 320D, 320E, and 320F or later FAA Approved revisions of the above supplement.

2. FAA/DAS Approved Supplemental Flight Manual, P/N 891181, Revision 1, dated 5-11-01 is required for Cessna models 320B, 320C, 320D, 320E, and 320F for S-TEC System 55/55X or later FAA Approved revisions of the above supplement.

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

FAA Form 8110-2-1(10-69) Page 2 of 2

## Every issue (1)

- May 11, 2001: Amended, Current. [certificate](https://openairdocs.org/files/sha256/e3/51/e351303dfac2a33dceeed5623db11afa9e2f26c685125e8f9ce36689c031e69f)

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