# STC SA7785SW-D

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: S-TEC Corporation, United States
- Description: Installation of S-TEC System 40/50, single and two axis automatic flight guidance systems, model ST-270-40/50.
- Applied: April 1, 1991
- Status date: April 5, 1991
- 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/ca/32/ca3259318b68615edd0368dc7e59120e87c17ad0c8b9e8d743d137b4fb1644c9
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/54168431FB9E5C5C85256CC20056A48D.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA7785SW-D

## ADs that name it (0)

None.

## Approved models (5)

- The Cessna Aircraft Company 320B ([TCDS 3A25](https://openairdocs.org/tcds/3A25))
- The Cessna Aircraft Company 320C ([TCDS 3A25](https://openairdocs.org/tcds/3A25))
- The Cessna Aircraft Company 320D ([TCDS 3A25](https://openairdocs.org/tcds/3A25))
- The Cessna Aircraft Company 320E ([TCDS 3A25](https://openairdocs.org/tcds/3A25))
- The Cessna Aircraft Company 320F ([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.

flinri £ma rf avrin Btparrmmt of transportation —federal Station Administration Supplemental 'Cgpe Certificate — y—y*rt/<4trrm mrrifl i^r SA7785SW-D S-TEC Corporation Rt. 4, Bldg. 946 Wolters Industrial Complex Mineral Wells, Texas 76067 C 1 V 1 1 AirrrtV 3A25 Cessna 320B, 320C, 320D, 320E, and 320F Installation of S-TEC System 40/50, Single and Two Axis Automatic Flight Guidance Systems, Model ST-270-40/50, according to Bulletin No. 370, Revision 2, dated 3-29-91 and Master Drawing List No. 92366, Revision B, dated 3-29-91 and/or later FAA Approved revisions of the above data (28 Volt System).

1. FAA Approved Supplemental Flight Manual, P/N 89912, dated 4-05-91 is required for S-TEC System 40 for Cessna Models 320B, 320C, 320D, 320E, and 320F and/or later FAA Approved revisions of the above supplement.

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

S%c/rrU 4-01-91 4-05-91 y-A- •.. ..

William J. ThomasDAS Staff rnnrrHnatnr, DAS (TMlt) fine of not exceeding tl ,000, or imprisonment not exceeding 3 years, or both.

7*Au etrtijkate may bt traiafmij in mcctr Janet unlh FAR 21.17.

ttratrd Starts of 3nmn Bepartmcnt of Xransportanon— jp cderal Sttnation administration Supplemental Itgpe Certificate(Continuation SA7785SW-D Limitations and Conditions (con't.)

2. FAA Approved Supplemental Flight Manual, P/N 89914, dated 4-05-91 is required for S-TEC System 50 for Cessna Models 320B, 320C, 320D, 320E, and 320F and/or later FAA Approved revisions of the above supplement.

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

.-In] alteration of this certificate is punishable by afiru of not exceeding SI,OOP, or imprisonment not exceeding 3 years, or hnth.

FAA FORM «iio.l-t (to-M> Thil cirttfeati may bt Irani/arid in accordant! tuitH I'.Mt .'/.•/*.

ilv. Stale, and ^JP code I Extent of Authority (if licensing agreement):

Signature of grantor (hi ink):

## Every issue (1)

- April 5, 1991: Issued, Current. [certificate](https://openairdocs.org/files/sha256/ca/32/ca3259318b68615edd0368dc7e59120e87c17ad0c8b9e8d743d137b4fb1644c9)

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