# STC SA09357AC-D

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: S-TEC Corporation, United States
- Description: Installation of S-TEC System 30 alt altitude hold system Model ST-813
- Applied: April 9, 1998
- Status date: April 13, 1998
- Product: Aircraft, Small Airplane
- Certification basis: Part 21
- Data sheets: [TCDS 3A25](https://openairdocs.org/tcds/3A25)
- Certificate PDF: https://openairdocs.org/files/sha256/7c/5a/7c5a90e345c885e3ffff217d3397f2d68ca503737094b1ceb3b5cda34bd8fb94
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/E97C67E30D96A7B185256CC1007F3AB1.0001
- DRS record last changed: December 5, 2025
- Page: https://openairdocs.org/stc/SA09357AC-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 5A09357 AC-D This certificate issued to: S-TEC Corporation One S-TEC Way Mineral Wells Municipal Airport Mineral Wells, TX 76067-9236 9 art 3 of the Cirt Is Regulations.

Original Product I ype Cerlifcate Number: 3A25 Make: Cessna Model: 320B, 320C, 320D, 320E, and 320F Description of Type Design Change:

Installation of S-TEC System 30 ALT Altitude Hold System, Model ST-813, according to Bulletin No.

913, dated 4-08-98 and Master Drawing List No. 921088, dated 4-08-98 or later FAA Approved revisions of the above data (28 Volt System).

FAA/DAS Approved Supplemental Flight Manual, P/N 891714, is required for Cessna Models 320B, 320C, 320D, 320E, and 320F or later FAA Approved revisions of the above supplement.

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

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.

suspended, revoked or a termination date is otherese established by the Administrator of the Federal I viation Administration.

Date of Application: 4-09-98 Date Amended:

Date of Issuance: 4-13-98 By Direction of the Administrator FEDERAL AVIATION (Signature) TMINISTRATIOR William J. Thomas DAS Staff Coordinator, DAS 5 SW (Title)

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, State, and ZIP code) Extent of Authority (if licensing agreement):

Signature of grantor (In ink):

## Every issue (1)

- April 13, 1998: Issued, Current. [certificate](https://openairdocs.org/files/sha256/7c/5a/7c5a90e345c885e3ffff217d3397f2d68ca503737094b1ceb3b5cda34bd8fb94)

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