# STC SA2735SO

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: Chelton Aviation Corporation, United States
- Description: Installation of the OCEM autopilot system AP-2B or AP-3B.
- Applied: September 18, 1987
- Status date: April 6, 2004
- Product: Aircraft, Single-Engine
- Certification basis: Part 3, Part 21
- Data sheets: [TCDS 3A12](https://openairdocs.org/tcds/3A12)
- Certificate PDF: https://openairdocs.org/files/sha256/7e/cd/7ecdbca51238cf2c1e8e9cec69d7ddff8e977c3c93f7a323da73612e60b126f6
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/682EE2B17B45A8CA86256E830066B8D6.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA2735SO

## ADs that name it (0)

None.

## Approved models (15)

- The Cessna Aircraft Company 172 ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- The Cessna Aircraft Company 172A ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- The Cessna Aircraft Company 172B ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- The Cessna Aircraft Company 172C ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- The Cessna Aircraft Company 172D ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- The Cessna Aircraft Company 172E ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- The Cessna Aircraft Company 172F (USAF T-41A) ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- The Cessna Aircraft Company 172G ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- The Cessna Aircraft Company 172H (USAF T-41A) ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- The Cessna Aircraft Company 172I ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- The Cessna Aircraft Company 172K ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- The Cessna Aircraft Company 172L ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- The Cessna Aircraft Company 172M ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- The Cessna Aircraft Company 172N ([TCDS 3A12](https://openairdocs.org/tcds/3A12))
- The Cessna Aircraft Company 172P ([TCDS 3A12](https://openairdocs.org/tcds/3A12))

## 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.

Number SA2735SO This certificate issued to Chelton Aviation Corporation 5011 Sabre Drive Denton, Texas 76207

Part 3 of the Civil Aviation Regulations.

Original Product--Type Certificate Number : 3A12 Make :

Cessna 172, 172-A thru I, K, L, M, N, P Description of Type Design Change: Installation of the OCEM Autopilot System AP-2B or AP-3B in accordance with Installation Manual dated April 8, 1990, or later FAA Approved revision or installation of the OCEM Autopilot System AP-2C, or AP-3C in accordance with “Automatic Flight Systems OCEM AP- 2C, AP-3C Installation Manual for Aircraft Cessna Models 172, 172A, 172B, 172C, 172D, 172E, 172F, 172G, 172H, 172I, 172K, 172L, 172M, 172N, 172P” dated June , 1992, or later FAA Approved revisions.

Limitations and Conditions: This approval should not be extended to other aircraft of this model on which other previously approved modifications are incorporated, unless it is determined by the installer that the interrelationship between this change and any other previously approved modifications will produce no adverse effect upon the airworthiness of that airplane. FAA Approved Flight Manual Supplement, dated April 18, 1990, for the AP-3B or dated December 30, 1993, for the AP-2B or FAA Approved Airplane Flight Manual Supplement for the Ap-2C or the AP-3C both dated 3/28/95, or later FAA Approved revisions, is a required 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 : September 18, 1987 Date of issuance : April 18, 1990 Date reissued : April 6, 2004

Date amended : December 30, 1993, March 28, 1995, September 4, 1997

(Signature) Melvin D. Taylor Manager Atlanta Aircraft Certification Office

(Title)

## Every issue (1)

- April 6, 2004: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/7e/cd/7ecdbca51238cf2c1e8e9cec69d7ddff8e977c3c93f7a323da73612e60b126f6)

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