# STC ST566CH

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: ElectroSonics Div of AiRadio Corporation, United States
- Description: Installation of an AlliedSignal/Sundstrand Mark VI ground proximity warning system (GPWS).
- Status date: November 1, 1996
- Product: Aircraft, Large Multi-Engine
- Certification basis: Part 21
- Data sheets: [TCDS A-669](https://openairdocs.org/tcds/A-669)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/24CB77301D5A121A85256CC30003608C.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/ST566CH

## ADs that name it (0)

None.

## Approved models (5)

- McDonnell Douglas Corporation DC3C-R-1830-90C (Army C-47B) ([TCDS A-669](https://openairdocs.org/tcds/A-669))
- McDonnell Douglas Corporation DC3C-R-1830-90C (Navy R4D-6) ([TCDS A-669](https://openairdocs.org/tcds/A-669))
- McDonnell Douglas Corporation DC3C-S1C3G ([TCDS A-669](https://openairdocs.org/tcds/A-669))
- McDonnell Douglas Corporation DC3C-S4C4G ([TCDS A-669](https://openairdocs.org/tcds/A-669))
- McDonnell Douglas Corporation DC3C-SC3G ([TCDS A-669](https://openairdocs.org/tcds/A-669))

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