# STC ST473CH

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: Avionics Group Inc., United States
- Description: Installation of an AlliedSignal Mark VII ground proxomity and windshear warning system.
- Status date: December 20, 1995
- 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/A82592EB334E12D485256CC30003603C.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/ST473CH

## ADs that name it (0)

None.

## Approved models (1)

- McDonnell Douglas Corporation DC-9-21 ([TCDS A6WE](https://openairdocs.org/tcds/A6WE))

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