# STC SA721AL

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: Schneider Richard J, United States
- Description: Installation of Schneider Model SWS-4000 main wheel skis and Schneider Model SWS-1000 tail wheel skis.
- Status date: March 25, 1981
- Product: Aircraft, Single-Engine
- Certification basis: Part 21
- Data sheets: [TCDS 1A6](https://openairdocs.org/tcds/1A6)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/EE25DA1B80E8D3D485256CC20056A21A.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA721AL

## ADs that name it (0)

None.

## Approved models (8)

- The New Piper Aircraft Inc. PA-22 ([TCDS 1A6](https://openairdocs.org/tcds/1A6))
- The New Piper Aircraft Inc. PA-22-108 ([TCDS 1A6](https://openairdocs.org/tcds/1A6))
- The New Piper Aircraft Inc. PA-22-135 ([TCDS 1A6](https://openairdocs.org/tcds/1A6))
- The New Piper Aircraft Inc. PA-22-150 ([TCDS 1A6](https://openairdocs.org/tcds/1A6))
- The New Piper Aircraft Inc. PA-22-160 ([TCDS 1A6](https://openairdocs.org/tcds/1A6))
- The New Piper Aircraft Inc. PA-22S-135 ([TCDS 1A6](https://openairdocs.org/tcds/1A6))
- The New Piper Aircraft Inc. PA-22S-150 ([TCDS 1A6](https://openairdocs.org/tcds/1A6))
- The New Piper Aircraft Inc. PA-22S-160 ([TCDS 1A6](https://openairdocs.org/tcds/1A6))

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