# STC SA1851SO

- Type: Supplemental type certificate
- Status: Current, Amended
- Holder: Avionics & Aircraft Systems, Inc., United States
- Description: Installation of the Canadian Marconi CMA 771 Alpha Mark III VLF/Omega Navigation System.
- Status date: November 19, 1987
- Product: Aircraft, Large Multi-Engine
- Certification basis: Part 21
- Data sheets: [TCDS 4A25](https://openairdocs.org/tcds/4A25)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/23764D0C5CD9B4C385256CC10083D1A1.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA1851SO

## ADs that name it (0)

None.

## Approved models (2)

- McDonnell Douglas Corporation DC-8-61 ([TCDS 4A25](https://openairdocs.org/tcds/4A25))
- McDonnell Douglas Corporation DC-8-63 ([TCDS 4A25](https://openairdocs.org/tcds/4A25))

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