# STC SA840NW

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: Yarcho, William A., United States
- Description: Installation of a lycoming engine, Sensenich propeller, PA-22 balanced elevators and an overhead sky light window
- Applied: June 24, 1979
- Status date: October 1, 1979
- Product: Aircraft, Small Airplane
- Certification basis: Part 21
- Data sheets: [TCDS 1A1](https://openairdocs.org/tcds/1A1)
- Certificate PDF: https://openairdocs.org/files/sha256/19/6a/196a782daf06ac9fd69b08fbd799c7c18affc1cdb76a7e3de3b915607d39340c
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/F7BC2AB74E5A9F1F86257A3D006D1867.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA840NW

## ADs that name it (0)

None.

## Approved models (1)

- Piper Aircraft Inc. PA-16 ([TCDS 1A1](https://openairdocs.org/tcds/1A1))

## What the certificate says

The certificate is a scan without a text layer; open the PDF to read it.

## Every issue (1)

- October 1, 1979: Issued, Current. [certificate](https://openairdocs.org/files/sha256/19/6a/196a782daf06ac9fd69b08fbd799c7c18affc1cdb76a7e3de3b915607d39340c)

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