# STC ST870SO

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: Southern Airways, Inc, United States
- Description: Installation of Collins FPC 75 ground proximity warning system.
- Status date: November 25, 1975
- Product: Aircraft, Large Multi-Engine
- Certification basis: Part 21
- Data sheets: [TCDS A6WE](https://openairdocs.org/tcds/A6WE)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/DA89ACD27EF7444385256CC3000374BC.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/ST870SO

## ADs that name it (0)

None.

## Approved models (2)

- McDonnell Douglas Corporation DC-9-10 Series ([TCDS A6WE](https://openairdocs.org/tcds/A6WE))
- McDonnell Douglas Corporation DC-9-30 Series ([TCDS A6WE](https://openairdocs.org/tcds/A6WE))

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