# STC SH173WE

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: Western Helicopters, Inc, United States
- Description: Installation of derated Lycoming TVO-435-B1A or TVO-435-B1B engine in lieu of TVO-435-A1A engine using existing TVO-435-A1A installation components.
- Status date: November 11, 1974
- Product: Aircraft, Rotorcraft
- Certification basis: Part 21
- Data sheets: [TCDS 2H3](https://openairdocs.org/tcds/2H3)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/A90BAADA3720CFB885256CC2005C2EF9.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SH173WE

## ADs that name it (0)

None.

## Approved models (1)

- Bell Helicopter Textron 47G-3B ([TCDS 2H3](https://openairdocs.org/tcds/2H3))

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