# STC SPW-2

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: Northwest Propeller Inc, United States
- Description: Modification of Hamilton Standard4A2-V5 propeller governor to NWP-D18 on aircraft with Pratt & Whitney R-985 engines.
- Status date: January 1, 1960
- Product: Propeller
- Certification basis: Part 21
- Data sheets: [TCDS P-891](https://openairdocs.org/tcds/P-891)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/E9885658FF202E84862570C200618795.0001
- DRS record last changed: December 5, 2025
- Page: https://openairdocs.org/stc/SPW-2

## ADs that name it (0)

None.

## Approved models (1)

- Hartzell Propeller Inc. HC-93Z ([TCDS P-891](https://openairdocs.org/tcds/P-891))

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