# STC SA7221SW-D

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: S-TEC Corporation, United States
- Description: Installation of S-TEC manual electric trim system, model ST-328.
- Applied: May 17, 1990
- Status date: June 8, 1990
- Product: Aircraft, Single-Engine
- Certification basis: Part 21
- Data sheets: [TCDS 3A17](https://openairdocs.org/tcds/3A17)
- Certificate PDF: https://openairdocs.org/files/sha256/7b/ab/7babbe446c58e9d1ba4344263f253a8d01f463869444b17207d127b396135b22
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/62E90189BBE781E485256CC20056A222.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA7221SW-D

## ADs that name it (0)

None.

## Approved models (4)

- The Cessna Aircraft Company R172E Series ([TCDS 3A17](https://openairdocs.org/tcds/3A17))
- The Cessna Aircraft Company R172F (USAF T-41D) ([TCDS 3A17](https://openairdocs.org/tcds/3A17))
- The Cessna Aircraft Company R172G Series ([TCDS 3A17](https://openairdocs.org/tcds/3A17))
- The Cessna Aircraft Company R172H (USAF T-41D) ([TCDS 3A17](https://openairdocs.org/tcds/3A17))

## What the certificate says

This is OCR from the scanned FAA certificate. OCR can misread letters and numbers.

red Sate a Sucia Department of Transportation Federal Aviation Administration Supplemental Type Certificate Number: SA7221SW-D This certificate issued to: S-TEC Corporation Rt. 4, Bldg 946 Wolters Industrial Complex Mineral Wells, TX 76067 Port 3 of the CiVIl Air Regulations.

Original Product -Type Cortificato Numbor: 3A17 Make: CESSNA Model: R172E, R172F, R172G & R172H Description of Type Design Change:

Installation of S-TEC Manaul Electric Trim System, Model SI-328, according to Bulletin No. 428, dated 5-08-90 and Master Drawing List No. 92517, dated 5-08-90 and/or later FAA Approved revisions of the above data (14 Volt System).

1. FAA/DAS Approved Supplemental Flight Manual, P/N 89871, dated 6-08-90 is required for Cessna Models R172E, R172F, R172G & R172H and/or later FAA Approved revisions of the above supplement.

2. Compatability of this modification with other previously approved modifications must be determined by the installer.

6-08-90 Date Amended:

FEDERAL AVIATION (Signalure) TOMINIS187 TION Harold W. Holdeman DAS Staff Coordinator, DAS 5 SW (Tille)

47.

TRANSFER ENDORSEMENT Transfer the ownership of Supplemental Type Certificate Number to (Name of transferee) (Address of transferee) (Number and street) (City, State, and Z1P code) from (Name of grantor) (Print or type) (Address of grantor) (Number and street) (City, State, and ZIP code) Exent of Authority (if licensing agreement) :

Signature of grantor (In ink] :

## Every issue (1)

- June 8, 1990: Issued, Current. [certificate](https://openairdocs.org/files/sha256/7b/ab/7babbe446c58e9d1ba4344263f253a8d01f463869444b17207d127b396135b22)

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