# STC SE78WE

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: Yehnert Helicopters, Inc, United States
- Description: Install two locking pins in Franklin Part Number 21014J oil transfer collar, 180 degrees apart, to prevent rotation of oil seal in collar.
- Status date: August 11, 1976
- Product: Engine
- Certification basis: Part 21
- Data sheets: [TCDS E9EA](https://openairdocs.org/tcds/E9EA)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/D1C2031C9E60626385256CC2005C2D41.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SE78WE

## ADs that name it (0)

None.

## Approved models (3)

- Wytwornia Sprzetu Komunikacyjnego 6A-350-C1 ([TCDS E9EA](https://openairdocs.org/tcds/E9EA))
- Wytwornia Sprzetu Komunikacyjnego 6A-350-C1A ([TCDS E9EA](https://openairdocs.org/tcds/E9EA))
- Wytwornia Sprzetu Komunikacyjnego 6A-350-C2 ([TCDS E9EA](https://openairdocs.org/tcds/E9EA))

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