# STC SA09401AC-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-853,
- Applied: March 9, 1999
- Status date: March 14, 2001
- Product: Aircraft, Small Multi-Engine
- Certification basis: Part 21
- Data sheets: [TCDS A7CE](https://openairdocs.org/tcds/A7CE)
- Certificate PDF: https://openairdocs.org/files/sha256/14/07/1407724475495d249d74bbc912e6701731eee02e91db79f4f073de916dfb7e8c
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/D60CCF804D91D40C85256CC1007F3AE3.0001
- DRS record last changed: December 5, 2025
- Page: https://openairdocs.org/stc/SA09401AC-D

## ADs that name it (0)

None.

## Approved models (6)

- Cessna Aircraft Company 401 ([TCDS A7CE](https://openairdocs.org/tcds/A7CE))
- Cessna Aircraft Company 401A ([TCDS A7CE](https://openairdocs.org/tcds/A7CE))
- Cessna Aircraft Company 401B ([TCDS A7CE](https://openairdocs.org/tcds/A7CE))
- Cessna Aircraft Company 402A ([TCDS A7CE](https://openairdocs.org/tcds/A7CE))
- Cessna Aircraft Company 402B ([TCDS A7CE](https://openairdocs.org/tcds/A7CE))
- Cessna Aircraft Company 402C ([TCDS A7CE](https://openairdocs.org/tcds/A7CE))

## 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: SA09401 AC-D This certificate issued to: S-TEC Corporation One S-TEC Way Mineral Wells Municipal Airport Mineral Wells, TX 76067-9236 Certifies that the change in the type design for the fillaring paduct with the timitations and conditions therefos as prefed heren meets the ancothiness squirements of Fast 2 of the Cirl sta Regulations.

Original Product I ype Certifeate A umber: A7CE Al ate : Cessna Model: 401, 401A, 401B, 402A, 402B, and 402C Description of Type Design Change:

Installation of S-TEC System 55/55X Two Axis Automatic Flight Guidance System, Model ST-853, according to Bulletin No. 953, Revision 3, dated 3-14-01 and Master Drawing List No. 921151, Revision C, dated 3-14-01 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.

Late of affliction: 3-09-99 Jafe wissued:

I ate of ismance: 3-12-99 Date Amended: 3-14-01 FEDERAL AVIATION By direction of the 1 dministator (Signature) TOMINSTRATIO 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: SA09401AC-D Limitations and Conditions: (con't.)

FAA/DAS Approved Pilot's Operating Handbook and/or Airplane Flight Manual Supplement, P/N 891835, dated 3-12-99 is required for Cessna models 401, 401A, and 401B or later FAA Approved revisions of the above supplement.

2. FAA/DAS Approved Pilot's Operating Handbook and/or Airplane Flight Manual Supplement, P/N 891836, dated 3-12-99 is required for Cessna models 402A and 402B or later FAA Approved revisions of the above supplement.

3. FAA/DAS Approved Pilot's Operating Handbook and/or Airplane Flight Manual Supplement, P/N 891837, dated 3-12-99 is required for Cessna model 402C or later FAA Approved revisions of the above supplement.

4. FAA/DAS Approved Pilot's Operating Handbook and/or Airplane Flight Manual Supplement, P/N 891835, Revision 1, dated 3-14-01 is required for Cessna models 401, 401A, and 401B for S-TEC System 55/55X or later FAA Approved revisions of the above supplement.

FAA/DAS Approved Pilot's Operating Handbook and/or Airplane Flight Manual Supplement, P/N 891836, Revision 1, dated 3-14-01 is required for Cessna models 402A and 402B for S-TEC System 55/55X or later FAA Approved revisions of the above supplement.

6. FAA/DAS Approved Pilot's Operating Handbook and/or Airplane Flight Manual Supplement, P/N 891837, Revision 1, dated 3-14-01 is required for Cessna model 402C for S-TEC System 55/55X or later FAA Approved revisions of the above supplement.

7. 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

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)

- March 14, 2001: Amended, Current. [certificate](https://openairdocs.org/files/sha256/14/07/1407724475495d249d74bbc912e6701731eee02e91db79f4f073de916dfb7e8c)

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