# STC SA4-309

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: Jay- Dee Aircraft Supply Co, United States
- Description: Engine cowling and baffles for aircraft with Pratt & Whitney R-1830-92 engines incorporating R-1830-75 or -94 cylinders.
- Status date: September 27, 1974
- 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/646FEE2C09FB3A6F85256CC2000C5E4A.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA4-309

## ADs that name it (0)

None.

## Approved models (3)

- McDonnell Douglas Corporation DC-3A Series ([TCDS A-669](https://openairdocs.org/tcds/A-669))
- McDonnell Douglas Corporation DC-3C Series ([TCDS A-669](https://openairdocs.org/tcds/A-669))
- McDonnell Douglas Corporation DC-3D Series ([TCDS A-669](https://openairdocs.org/tcds/A-669))

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