# STC SA1528SO

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: Ontic Engineering and Manufacturing Inc., United States
- Description: Installation of Litton LTN 72R inertial navigation system utilizing software program 72-7 supplement 72-19 installed
- Applied: August 29, 1983
- Status date: March 17, 2022
- Product: Aircraft, Small Airplane
- Certification basis: Part 3, Part 21
- Data sheets: [TCDS A5SW](https://openairdocs.org/tcds/A5SW)
- Certificate PDF: https://openairdocs.org/files/sha256/6f/ed/6fedad77d65ee8f743c185869adf0db6fa871a2d334d48ccb9a37ef308206434
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/FCE7FE313A02E2308625882B004E9DB1.0001
- DRS record last changed: December 5, 2025
- Page: https://openairdocs.org/stc/SA1528SO

## ADs that name it (0)

None.

## Approved models (1)

- M7 Aerospace LLC SA227-AT ([TCDS A5SW](https://openairdocs.org/tcds/A5SW))

## 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.

SA1528SO Ontic Engineering and Manufacturing, Inc.

1176 Telecom Drive Creedmoor, NC 27522 Part 3 the Civil Air Regulations A5SW Fairchild/Swearingen SA227-AT, (Merlin) Installation of Litton LTN 72R Inertial Navigation System utilizing Software Program 72-7 and Supplement 72-19 installed in accordance with appropriate drawings as listed in Master Drawing List, Report No.

DC83V001, Revision K, dated November 7, 1983, or later FAA approved revision.

(See continuation sheet 3 of 3) August 29, 1983 November 5, 1987; January 9, 1991; June 28, 2012;

March 17, 2022 December 16, 1983 S. Frances Cox Acting Manager, Fort Worth ACO Branch, Compliance & Airworthiness Division Aircraft Certification Service 3

SA1528SO 3

SA1528SO Date of Issuance: December 16, 1983 Date of Reissuance: December 17, 2021

The installer must determine whether this design change is compatible with previously approved modifications. If the holder agrees to permit another person to use this certificate to alter a product, the holder must give the other person written evidence of that permission. FAA Approved Airplane Flight Manual Supplement dated December 16, 1983, is a required part of this STC. FAR 43 is adequate to insure Continued Airworthiness of this modification.

-END- 3 3

## Every issue (2)

- March 17, 2022: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/6f/ed/6fedad77d65ee8f743c185869adf0db6fa871a2d334d48ccb9a37ef308206434)
- June 28, 2012: Reissued, Historical. [certificate](https://openairdocs.org/files/sha256/7d/2b/7d2ba4f48bc9bff812a7e32166b660867c95c4e94992f5f4096634b721bee46a)

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