# STC SA09374AC-D

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: S-TEC Corporation, United States
- Description: Installation of S-TEC System 30 ALT Altitude Hold System, Model ST-825.
- Applied: June 15, 1998
- Status date: June 18, 1998
- Product: Aircraft, Single-Engine
- Certification basis: Part 21
- Data sheets: [TCDS 3A15](https://openairdocs.org/tcds/3A15)
- Certificate PDF: https://openairdocs.org/files/sha256/49/fe/49fe0af9f194049f6f24ac43b9e58dcce33fec3cd17633488d6adb4db5fe0d05
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/E8E210A8DF1672C385256CC1007F3AC5.0001
- DRS record last changed: December 5, 2025
- Page: https://openairdocs.org/stc/SA09374AC-D

## ADs that name it (0)

None.

## Approved models (12)

- Beechcraft Corporation 35-33 ([TCDS 3A15](https://openairdocs.org/tcds/3A15))
- Beechcraft Corporation 35-A33 ([TCDS 3A15](https://openairdocs.org/tcds/3A15))
- Beechcraft Corporation 35-B33 ([TCDS 3A15](https://openairdocs.org/tcds/3A15))
- Beechcraft Corporation 35-C33 ([TCDS 3A15](https://openairdocs.org/tcds/3A15))
- Beechcraft Corporation 35-C33A ([TCDS 3A15](https://openairdocs.org/tcds/3A15))
- Beechcraft Corporation E33 ([TCDS 3A15](https://openairdocs.org/tcds/3A15))
- Beechcraft Corporation E33A ([TCDS 3A15](https://openairdocs.org/tcds/3A15))
- Beechcraft Corporation E33C ([TCDS 3A15](https://openairdocs.org/tcds/3A15))
- Beechcraft Corporation F33 ([TCDS 3A15](https://openairdocs.org/tcds/3A15))
- Beechcraft Corporation F33A ([TCDS 3A15](https://openairdocs.org/tcds/3A15))
- Beechcraft Corporation F33C ([TCDS 3A15](https://openairdocs.org/tcds/3A15))
- Beechcraft Corporation G33 ([TCDS 3A15](https://openairdocs.org/tcds/3A15))

## 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: SA09374 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 following product with the finitations and conditions therefer as speciped hereon meets the aiworthiness requiements of fat 3 of the Cord do Kegulations.

Original Product I ype Certifcate A umter: ЗА15 Make: Beech Model: 35-33, 35-А33, 35-В33, 35-С33, 35-С33А, Е33.

E33A, E33C, F33, F33C, G33, and F33A Description of Type Design Change:

Installation of S-TEC System 30 ALT Altitude Hold System, Model ST-825, according to Bulletin No 925, dated 6-15-98 and Master Drawing List No. 921102, dated 6-15-98 or later FAA Approved revisions of the above data (14 Volt System).

Only eligible on Beech Model F33A, S/N CE-315 & Below.

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.

Date of Application: 6-15-98 Date Reissued:

Late of ismance: 6-18-98 Date Amended:

By Direction of the Administrator FEDERAL AVIATION Mill 1L (Signature) TOMINSTRATO Mike Keirnan DAS Staff Coordinator, DAS 5 SW (Title)

United States of America Department of Transportation Federal Aviation Administration Supplemental Type Certificate (Continuation Sheet) Number: SA09374AC-D Limitations and Conditions: (con't.)

2. FAA/DAS Approved Pilot's Operating Handbook and/or Airplane Flight Manual Supplement, P/N 891748, dated 6-18-98 is required for Beech Models 35-33, 35-A33, and 35-B33 or later FAA Approved revisions of the above supplement.

FAA/DAS Approved Pilot's Operating Handbook and/or Airplane Flight Manual Supplement, P/N 891749, dated 6-18-98 is required for Beech Models 35-C33, 35-C33A, E33, E33A, E33C, F33, F33A, S/N CE-315 and Below, F33C and G33 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.

FAA Form 811C-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)

- June 18, 1998: Issued, Current. [certificate](https://openairdocs.org/files/sha256/49/fe/49fe0af9f194049f6f24ac43b9e58dcce33fec3cd17633488d6adb4db5fe0d05)

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