# STC SA09361AC-D

- Type: Supplemental type certificate
- Status: Current, Amended
- Holder: S-TEC Corporation, United States
- Description: Installation of S-TEC system 30 alt altitude hold system Model ST-821
- Applied: April 28, 1998
- Status date: May 27, 1999
- Product: Aircraft, Small Airplane
- Certification basis: Part 21
- Data sheets: [TCDS 3A23](https://openairdocs.org/tcds/3A23)
- Certificate PDF: https://openairdocs.org/files/sha256/a1/6b/a16b511e40e18c43ff8a7e213e325c0849c15615389b5dd1452103c24280d295
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/0774FE1B9BB8D47885256CC1007F3AB3.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA09361AC-D

## ADs that name it (0)

None.

## Approved models (4)

- Maule Aerospace Technology Inc. MT-7-235 ([TCDS 3A23](https://openairdocs.org/tcds/3A23))
- Maule Aerospace Technology Inc. MX-7-180A ([TCDS 3A23](https://openairdocs.org/tcds/3A23))
- Maule Aerospace Technology Inc. MX-7-180B ([TCDS 3A23](https://openairdocs.org/tcds/3A23))
- Maule Aerospace Technology Inc. MX-7-180C ([TCDS 3A23](https://openairdocs.org/tcds/3A23))

## 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: SA09361AC-D This certificate issued to: S-TEC Corporation One S-TEC Way Mineral Wells Municipal Airport Mineral Wells, TX 76067-9236 Past 3 of the Civil din Regulations.

Criginal I soduel Type Certificate A nember: 3A23 Make: Maule Model: MX-7-180A, MX-7-180B, MX-7-180C, and MT-7-235 Description of Type Design Change:

Installation of S-TEC System 30 ALT Altitude Hold System, Model ST-821, according to Bulletin No.

921, Revision 1, dated 5-24-99 and Master Drawing List No. 921091, Revision A, dated 5-24-99 or later FAA Approved revisions of the above data (28 Volt System).

FAA/DAS Approved Pilot's Operating Handbook and/or Airplane Flight Manual Supplement, P/N 891724, dated 4-30-98 is required for Maule Model MX-7-180C or later FAA Approved revisions of the above supplement.

(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.

2. FAA/DAS Approved Pilot's Operating Handbook and/or Airplane Flight Manual Supplement, P/N 891725, dated 4-30-98 is required for Maule Model MT-7-235 or later FAA Approved revisions of the above supplement.

3. FAA/DAS Approved Pilot's Operating Handbook and/or Airplane Flight Manual Supplement, P/N 891724, Revision 1, dated 5-27-99 is required for Maule models MX-7-180A, MX-7-180B, and MX-7-180C 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.

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)

- May 27, 1999: Amended, Current. [certificate](https://openairdocs.org/files/sha256/a1/6b/a16b511e40e18c43ff8a7e213e325c0849c15615389b5dd1452103c24280d295)

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