# STC SA635AL

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: Crosswinds STOL, United States
- Description: Install Avco Lycoming O-320-A2B engine and Sensenich propeller.
- Status date: June 6, 1978
- Product: Aircraft, Single-Engine
- Certification basis: Part 21
- Data sheets: [TCDS 1A4](https://openairdocs.org/tcds/1A4)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/5F1586366543594F85256CC200569F2B.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA635AL

## ADs that name it (0)

None.

## Approved models (2)

- The New Piper Aircraft Inc. PA-20 ([TCDS 1A4](https://openairdocs.org/tcds/1A4))
- The New Piper Aircraft Inc. PA-20-"135" ([TCDS 1A4](https://openairdocs.org/tcds/1A4))

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