# STC SA8370SW-D

- Type: Supplemental type certificate
- Status: Current, Amended
- Holder: S-TEC Corporation, United States
- Description: Installation of S-TEC System 40/50 single and two axis automatic flight guidance systems, Model ST-508.
- Applied: July 9, 1993
- Status date: July 29, 1994
- Product: Aircraft, Small Multi-Engine
- Certification basis: Part 21
- Data sheets: [TCDS 1A10](https://openairdocs.org/tcds/1A10)
- Certificate PDF: https://openairdocs.org/files/sha256/7e/3e/7e3e5114848036efc14b2e6f3e726ace20df0b9d5d5b335092790ff5db49e3d6
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/0A0144897FF4B67F85256CC20058E75C.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA8370SW-D

## ADs that name it (0)

None.

## Approved models (2)

- The New Piper Aircraft Inc. PA-23 ([TCDS 1A10](https://openairdocs.org/tcds/1A10))
- The New Piper Aircraft Inc. PA-23-160 ([TCDS 1A10](https://openairdocs.org/tcds/1A10))

## 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.

Bcparnrcnt of transportation —jfotoal Station administration Supplemental l^pc Certificate SA8370SW-D S-TEC Corporation 946 Pegram Mineral Wells, Texas 76067 ^ 3 y^ Civil Air : 1A10 PIPER PA-23 AND PA-23-160 Installation of S-TEC System 40/50 Single and Two Axis Automatic Flight Guidance Systems, Model ST-508, according to Bulletin No. 608, Revision 2, dated 7-21-94 and Master Drawing List No. 92587, Revision B, dated 7-21-94 or later FAA Approved revisions of the above data (14 Volt System).

1. Also eligible on Models PA-23 and PA-23-160 When Modified Per STC SA461SW, STC SA636SW, STC SA671SW, and STC SA899SW (Geronimo Conversion).

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

7-09-93 7-22-93 J&*^ri4*^ S£/mini& &L& —— u£J: 11-11-93, 7-29-94, Revision 2 William J. Thomas DAS Staff Coordinator. DAS 5 SW(Tilt.)

Any alteration oftkii ttrtificalt ii punishable by a fine of not exceeding SI,OOP, or imprisonment not exceeding 3 years, or both.

TAii ttrtijuatt may te traniferrtJ in accordant with FAR 21.47.

»AA Htm •) 10-2(10-4*1

ftniad Stain of 2ntnn Bepartment of Transportation— federal Nation administration Supplemental ICgpe Certificate(Continuation £heet) SA8370SW-D, Revision 2 Limitations and Conditions (con't.)

2. FAA/DAS Approved Airplane Flight Manual Supplement, P/N 891029, dated 7-22-93 is required for S-TEC System 40 for Piper Model PA-23-160 or later FAA Approved revisions of the above supplement.

3. FAA/DAS Approved Airplane Flight Manual Supplement, P/N 891029-1, dated 7_29-94 is required for S-TEC System 40 for Piper Models PA-23 and PA-23-160 or later FAA Approved revisions of the above supplement.

4. FAA/DAS Approved Airplane Flight Manual Supplement, P/N 891030, dated 7-22-93 is required for S-TEC System 50 for Piper Model PA-23-160 or later FAA Approved revisions of the above supplement.

5. FAA/DAS Approved Airplane Flight Manual Supplement, P/N 891030-1, dated 7_29-94 is required for S-TEC System 50 for Piper Models PA-23 and PA-23-160 or later FAA Approved revisions of the above supplement.

6. FAA/DAS Approved Airplane Flight Manual Supplement, P/N 891038, dated I-1-11-93 is required for S-TEC System 40 for Piper Model PA-23-160 When Modified Per STC SA461SW, STC SA636SW, STC SA671SW, and STC SA899SW (Geronimo Conversion) or later FAA Approved revisions of the above supplement.

7. FAA/DAS Approved Airplane Flight Manual Supplement, P/N 891038-1, dated 7-29-94 is required for S-TEC System 40 for Piper Models PA-23 and PA-23-160 When Modified Per STC SA461SW, STC SA636SW, STC SA671SW, and STC SA899SW (Geronimo Conversion) or later FAA Approved revisions of the above supplement,

8. FAA/DAS Approved Airplane Flight Manual Supplement, P/N 891039, dated II-11-93 is required for S-TEC System 50 for Piper Model PA-23-160 When Modified Per STC SA461SW, STC SA636SW, STC SA671SW, and STC SA899SW (Geronimo Conversion) or later FAA Approved revisions of the above supplement,

9. FAA/DAS Approved Airplane Flight Manual Supplement, P/N 891039-1, dated 7-29-94 is required for S-TEC System 50 for Piper Models PA-23 and PA-23-160 When Modified Per STC SA461SW, STC SA636SW, STC SA671SW, and STC SA899SW (Geronimo Conversion) or later FAA Approved revisions of the above supplement,

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

.•IHV alteration of this certificate is punishable by afiru of not exceeding 11,000, or imprisonment not exceeding 3 years, or hnih.

FAA FORM 1110.2-1 UO-M) THit ciriifeati may bt Hansftrnd in aceotdanct u/ilH I'AK .'/.•/*.

TRANSFER ENDORSEMENT Transfer the ownership of Supplemental Type Certificate Number to (Name of transferee) (Address of transferee) (Number and street) (City, State, and ^IP code) from (Name of grantor) (Print or type) (Address of grantor) (Number and street) (City, State, and £IP code) Extent of Authority (if licensing agreement):

Signature of grantor (In ink):.

U.S. GOVERNMENT PRINTING OFFICE : I9«6 OF—205-579

## Every issue (1)

- July 29, 1994: Amended, Current. [certificate](https://openairdocs.org/files/sha256/7e/3e/7e3e5114848036efc14b2e6f3e726ace20df0b9d5d5b335092790ff5db49e3d6)

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