# STC SA09221AC-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-679.
- Applied: May 19, 1997
- Status date: May 23, 1997
- Product: Aircraft, Single-Engine
- Certification basis: Part 21
- Data sheets: [TCDS 2A3](https://openairdocs.org/tcds/2A3)
- Certificate PDF: https://openairdocs.org/files/sha256/dd/69/dd69fb738dd4815d23a4e3c0fed5f0c4a8366ff98ae7ad146f59218c75948ad5
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/9345AC621685EB0D85256CC1007F3A24.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA09221AC-D

## ADs that name it (0)

None.

## Approved models (2)

- Mooney International Corporation M20J ([TCDS 2A3](https://openairdocs.org/tcds/2A3))
- Mooney International Corporation M20K ([TCDS 2A3](https://openairdocs.org/tcds/2A3))

## 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: SA09221 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 limitations and conditions therefor as specified hereon moots the airmorthiness requiements of Part 3 of the Civil sli Regulations.

Original Product I ype Certifcate Number: 2A3 Make: Mooney Model: M20J and M20K Description of Type Design Change:

Installation of S-TEC System 30 ALT Altitude Hold System, Model ST-679, according to Bulletin No. 779, dated 5-16-97 and Master Drawing List No. 92994, dated 5-16-97 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 891386, dated 5-23-97, is required for Mooney Model M20J or later FAA Approved revisions of the above supplement.

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

Date of Application: 5-19-97 Date Reissued:

Date of Issuance: 5-23-97 Date Amended:

By Direction of the Administrator FEDERAL AVIATION и Нитк Signdtur TOMINSTRATIOR DAS Staff Coordinator, DAS 5 SW William J. Thomas (Title)

United States of America Department of Transportation Federal Aviation Administration Supplemental Type Certificate (Continuation Sheet) Number: SA09221 AC-D Limitations and Conditions: (con't.)

2. FAA/DAS Approved Pilot's Operating Handbook and/or Airplane Flight Manual Supplement, P/N 891387, dated 5-23-97 is required for Mooney Model M20K 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.

FAA Form 8110-2-1 (10-69) Page 2 of 2

The FAA will reissue the certificate in the name of the transferee and futwant it to bim

TRANSFER ENDORSEMENT Transfer the ownership of Supplemental Type Certificate Number to (Name of transferee) (Address of transferee) (Number and street) (Cityx State, and 2IP 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 23, 1997: Issued, Current. [certificate](https://openairdocs.org/files/sha256/dd/69/dd69fb738dd4815d23a4e3c0fed5f0c4a8366ff98ae7ad146f59218c75948ad5)

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