# STC SA3425SW-D

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: Century Flight Systems Inc, United States
- Description: Installation of Century automatic flight system Model AK928 consisting of a Century 31 autopilot.
- Applied: October 23, 1984
- Status date: October 23, 1984
- Product: Aircraft, Single-Engine
- Certification basis: Part 21
- Data sheets: [TCDS 3A12](https://openairdocs.org/tcds/3A12)
- Certificate PDF: https://openairdocs.org/files/sha256/98/70/9870e4a82ab112bb9cb91ce02cbdd33148d269daf42aa72b64f4f3046cba260d
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/EEE0E1668A41158985256CC2000A97F1.0001
- DRS record last changed: December 5, 2025
- Page: https://openairdocs.org/stc/SA3425SW-D

## ADs that name it (0)

None.

## Approved models (10)

- Cessna Aircraft Company 172D ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- Cessna Aircraft Company 172E ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- Cessna Aircraft Company 172F (USAF T-41A) ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- Cessna Aircraft Company 172G ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- Cessna Aircraft Company 172H (USAF T-41A) ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- Cessna Aircraft Company 172I ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- Cessna Aircraft Company 172K ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- Cessna Aircraft Company 172L ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- Cessna Aircraft Company 172M ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- Cessna Aircraft Company 172N ([TCDS 3A12](https://openairdocs.org/tcds/3A12))

## 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: SA342554-7 This certificate issued to: Century Flight Systems, Inc..

P.O. Box 610 Mineral Wells, Texas 76067 Part 3 of the CIVII AIr Regulations.

Original Product -Type bientificate Numben: 3A12 Make: Cessna Model: 172D, 172E, 172F, 172G, 172H, 1721, Description of Type Design Change: 172K, 172L, 172M, and 172N Installation of Century Automatic Flight System Model AK928 consisting of a Century 31 Autopilot according to Bulletin No. 1058 dated 6-7-84 and Master Drawing List No. 87A1137 dated 6-7-84, or later FAA approved revision.

Pilot's Operating Handbook and FAA/DAS Approved Airplane Flight Manual Supplement dated 8-16-84 (P/N 68S969 is required.

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

Date of Application: October 23, 1984 Date Reissued:

Date of Issuance: . October 23, 1984 Date Amended:

FEDERA By Direction of the Administrator DAS Staff Coordinator DASTSW (Title) 47 FAA FORM B110-2 (10-68)

TRANSFER ENDORSEMENT Transfer the ownership of Supplemental Type Certificate Number to (Name of transferee) _ (Address of transferee) (139175 pro esquens") from (Name of grantor) (Print or type) (Address of grantor) ( Number and sireel ;

(City, Stake, and 218 codes Extent of Authority (if licensing agreement):

Signature of grantor (In ink): - +11+r. 0~: 1980-862-180

## Every issue (1)

- October 23, 1984: Issued, Current. [certificate](https://openairdocs.org/files/sha256/98/70/9870e4a82ab112bb9cb91ce02cbdd33148d269daf42aa72b64f4f3046cba260d)

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