# STC SA4-455

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: Executive Radio and Aircraft Svc Inc, United States
- Description: Hamilton Standard governors IM12-G5.
- Status date: January 1, 1960
- Product: Aircraft, Small Multi-Engine
- Certification basis: Part 21
- Data sheets: [TCDS 2A4](https://openairdocs.org/tcds/2A4), [TCDS 6A1](https://openairdocs.org/tcds/6A1)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/CA38829FAD38210C862570D00054DAD2.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA4-455

## ADs that name it (0)

None.

## Approved models (3)

- Twin Commander Aircraft Corporation 560 ([TCDS 6A1](https://openairdocs.org/tcds/6A1))
- Twin Commander Aircraft Corporation 680 ([TCDS 2A4](https://openairdocs.org/tcds/2A4))
- Twin Commander Aircraft Corporation 720 ([TCDS 2A4](https://openairdocs.org/tcds/2A4))

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