# STC SA7149SW-D

- Type: Supplemental type certificate
- Status: Current, Amended
- Holder: S-TEC Corporation, United States
- Description: Installation of S-TEC yaw damper system, Model ST-406.
- Applied: May 10, 1987
- Status date: September 28, 1992
- Product: Aircraft, Small Multi-Engine
- Certification basis: Part 21
- Data sheets: [TCDS 3A25](https://openairdocs.org/tcds/3A25)
- Certificate PDF: https://openairdocs.org/files/sha256/8d/ef/8defcd946babeb605e2fa6b93983feea6d46f91af1eb55bda3fbe83d7f5d548d
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/4A962FFB8BB05FAE85256CC20056A1AF.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA7149SW-D

## ADs that name it (0)

None.

## Approved models (3)

- The Cessna Aircraft Company 335 ([TCDS 3A25](https://openairdocs.org/tcds/3A25))
- The Cessna Aircraft Company 340 ([TCDS 3A25](https://openairdocs.org/tcds/3A25))
- The Cessna Aircraft Company 340A ([TCDS 3A25](https://openairdocs.org/tcds/3A25))

## What the certificate says

Read from the PDF's text layer, without the form's printed wording; the layout is lost and the order can differ. The PDF is the record.

&ata Btpartramt of transportation—jfotaal atnation administration Supplemental t^pe Certificate tSU4m&0T' SA7149SW-D S-TEC Corporation 946 Pegram Welters Industrial Park Mineral Wells, Texas 76067 3 ^^e- C i v i 1 Air : 3A25 Cessna 335, 340, and 340A Installation of S-TEC Yaw Damper System, Model ST-406, according to Bulletin No.

506, Revision 2, dated 8-21-92 and Master Drawing List No. 92441, Revision B, dated 8-21-92 and/or later FAA Approved revisions of the above data (28 Volt System).

1. Also eligible on Models 340 and 340A When Modified Per STC SE4327SW (RAM Engine Conversion) .

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

^cf*Tunj^ £flc6n*nt&/raZi>r-^ ^*~: 4-13-87 5-01-87 £,~~~J*t. 9-28-92, Revision 1 William J. Thomas DAS Staff Coordinator, DAS 5 SW (Title) Any alteration of this eertifieale it punishable by a,fine of not exceeding 17,000, or imprisonment not exceeding 3 years, or both.

TKit ttftijitale may Ar tTuuferrtd in aenrjfna wttk FAX 21.47.

Untied States of 2atnra Bcpartmtnt of Iransportanon— jfttol Stttanon administration Supplemental ICgpe Certificate(Continuation £heet) SA7149SW-D Limitations and Conditions (con't.)

2. FAA Approved Supplement to Pilot's Operating Handbook and/or FAA Approved Airplane Flight Manual, P/N 89739, dated 5-01-87 is required for Cessna Models 335, 340, and 340A and/or later FAA Approved revisions of the above supplement.

3. FAA Approved Supplement to Pilot's Operating Handbook and/or FAA Approved Airplane Flight Manual, P/N 89739-1, dated 9-28-92 is required for Cessna Models 335, 340, and 340A and 340 and 340A When Modified Per STC SE4327SW (RAM Engine Conversion) and/or later FAA Approved revisions of the above supplement.

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

'D alteration of this certificate is punishable by a fine of not exceeding Si,OOP, or imprisonment not exceeding 3 years, or bmh.

AA FORM si 10.J-1 («v««> Tint tirtipeatt may *« tfantfirriJ in aetardaiui with l-'Ali .'/.•/" PAGE 2 OF 2 PAGES

INSTRUCTIONS : The transfer endorsement below may be used to notify the appropriate FAA Regional Office of the transfer of this Supplemental Type Certificate.

The FAA will reissue the certificate in the name of the transferre and forward It to him.

TRANSFER ENDORSEMENT Transfer the ownership of Supplemental Type Certificate Number _ to (%jame of transferee) (Address of transferee) (9{um6er and strut) (City, State, andZlf cade) from (Qfyme of grantor) (Print or type) _ __ ___ ___ (Address of grantor) ___ strut) (City, State, andZlf code) Exent of Authority (if licensing agreement) :

Signature of grantor (In Page 2 of 2

## Every issue (1)

- September 28, 1992: Amended, Current. [certificate](https://openairdocs.org/files/sha256/8d/ef/8defcd946babeb605e2fa6b93983feea6d46f91af1eb55bda3fbe83d7f5d548d)

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