# STC SA8357SW-D

- Type: Supplemental type certificate
- Status: Current, Amended
- Holder: S-TEC Corporation, United States
- Description: Installation of S-TEC system 65 two axis automatic flight guidance system, Model ST-491.
- Applied: July 31, 1992
- Status date: February 28, 2002
- Product: Aircraft, Single-Engine
- Certification basis: Part 21
- Data sheets: [TCDS A-782](https://openairdocs.org/tcds/A-782)
- Certificate PDF: https://openairdocs.org/files/sha256/4d/32/4d326ce464e7399eeebdd72c6be0dd98b5d8218533d7f3ceabf94faa8ae6fdd9
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/A4C395ADE3F425F586256D1E00560A62.0001
- DRS record last changed: December 5, 2025
- Page: https://openairdocs.org/stc/SA8357SW-D

## ADs that name it (0)

None.

## Approved models (7)

- Navion Aircraft Company Ltd. Navion A (Army L-17B and L-17C) ([TCDS A-782](https://openairdocs.org/tcds/A-782))
- Navion Aircraft Company Ltd. Navion B ([TCDS A-782](https://openairdocs.org/tcds/A-782))
- Navion Aircraft Company Ltd. Navion D ([TCDS A-782](https://openairdocs.org/tcds/A-782))
- Navion Aircraft Company Ltd. Navion E ([TCDS A-782](https://openairdocs.org/tcds/A-782))
- Navion Aircraft Company Ltd. Navion F ([TCDS A-782](https://openairdocs.org/tcds/A-782))
- Navion Aircraft Company Ltd. Navion G ([TCDS A-782](https://openairdocs.org/tcds/A-782))
- Navion Aircraft Company Ltd. Navion H ([TCDS A-782](https://openairdocs.org/tcds/A-782))

## 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: SA8357SW-D This certificate issued to: S-TEC Corporation One S-TEC Way Mineral Wells Municipal Airport Mineral Wells, TX 76067-9236 Part 3 of the Civil l i Regulations.

Original Product I ype Certificate Number: A-782 Make: Navion Model: A, B, D, E, F, G, and H Description of Type Design Change:

Installation of S-TEC System 65 Two Axis Automatic Flight Guidance System, Model ST-491, according to Bulletin No. 591, Revision 2, dated 2-22-02 and Master Drawing List No. 92572, Revision B, dated 2-22-02 or later FAA Approved revisions of the above data (14 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: 7-31-92 Date Reissued:

Date of Issuance: 8-06-92 Date Amended: 2-28-02 By Direction of the Administrator FEDERAL AVIATION (Signature) TOMNISTRATO Michael Keirnan DAS Staff Coordinator, DAS S SW (Title)

United States of America Department of Transportation Federal Aviation Administration Supplemental Type Certificate (Continuation Sheet) Number: SA8357SW-D Limitations and Conditions: (con't.)

Eligibility limited to Navion models A, B, D, E, F, G, and H when modified by Palo Alto Airport, Inc. or Symon's Engineering horizontal stabilizer angle of incidence change with or without tip tanks and the above models when modified by 285 H.P. engine conversion.

FAA/DAS Approved Supplemental Flight Manual, P/N 89985, dated 8-06-92 is required for Navion Models A, B, D, E, and F When Modified Per STC SA4-241 (Stabilizer Modification) and STC SA4-915 (Tip Tanks) And The Above Models When Modified by 285 H.P. Engine Conversion and/or later FAA Approved revisions of the above supplement.

FAA/DAS Approved Supplemental Flight Manual, P/N 89985, Revision 1, dated 2-28-02 is required for Navion models A, B, D, E, F, G, and H when modified by Palo Alto Airport, Inc. or Symon's Engineering horizontal stabilizer angle of incidence change with or without tip tanks and the above models when modified by 285 H.P. engine conversion or later FAA Approved revisions of the above supplement.

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

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

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 and street) (City, State, and ZIP code) Extent of Authority (if licensing agreement): - Date of Transfer:

Signature of grantor (In ink):.

U.S. GOVERNMENT PRINTING OFFICE : 1966 OF-205-579 →

## Every issue (1)

- February 28, 2002: Amended, Current. [certificate](https://openairdocs.org/files/sha256/4d/32/4d326ce464e7399eeebdd72c6be0dd98b5d8218533d7f3ceabf94faa8ae6fdd9)

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