# STC SA323SO

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: Piedmont Aviation Inc, United States
- Description: Solid state voltage regulator.
- Status date: January 1, 1960
- Product: Aircraft, Large Multi-Engine
- Certification basis: Part 21
- Data sheets: [TCDS 7A1](https://openairdocs.org/tcds/7A1), [TCDS A-669](https://openairdocs.org/tcds/A-669)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/F76BF2C9F0A56D2E862570C2005E8AF8.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA323SO

## ADs that name it (0)

None.

## Approved models (2)

- Fairchild Industries Inc. F27 Series ([TCDS 7A1](https://openairdocs.org/tcds/7A1))
- McDonnell Douglas Corporation DC-3 Series ([TCDS A-669](https://openairdocs.org/tcds/A-669))

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