# STC SA706NW

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: Thunderbird Aero Maintenance, United States
- Description: Installation of a Hartzell HC-C2YK-1 BF/7666A propeller on a Lycoming O-360-A1A engine
- Applied: November 1, 1978
- Status date: January 11, 1979
- Product: Aircraft, Small Airplane
- Certification basis: Part 21
- Data sheets: [TCDS 1A15](https://openairdocs.org/tcds/1A15)
- Certificate PDF: https://openairdocs.org/files/sha256/e7/6e/e76e5111f642bc0f725e5615b97dc6e9f2872dc710f013f21887c3743925e00d
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/1AEB03CFB9BC32E386257A4400666422.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA706NW

## ADs that name it (0)

None.

## Approved models (1)

- Piper Aircraft Inc. PA-24 ([TCDS 1A15](https://openairdocs.org/tcds/1A15))

## What the certificate says

This is OCR from the scanned FAA certificate. OCR can misread letters and numbers.

STC United States of America Bool Department of Transportation Federal Aviation Administration Supplemental Type Certificate Number: SA706NW This certificate issued to: Thunderbird Aero Maintenance Purt 3 of the CiVil Air Regulations, effective November 1, 1949 including amendments 3-1 to 3-12.

Original Product -Type bertificate Number: 1A15 Make: Piper Model: PA-24 Description of Type Design Change: Installation of a Hartzel! HC-C2VK-1 BF/7666A propeller on a Lycoming 0-360-A1A engine in accordance with Thunderbird Aero Maintenance photos (1) through (3).

Limitations and Conditions: Data pertaining to this modification are considered inadequate for duplication in other aircraft. This approval is limited to the installation in Piper Model PA-24, S/N 24-1233 only. A copy of this Certificate, Thunderbird Aero Maintenance FAA Approved Flight Manual Supplement shall be maintained as part of the permanent records for the modified aircraft.

Date of Application: November 1, 1978 Date Reissued:

Date of Issuance: January 11, 1979 Date Amended:

FEDERAL AVIATION By Direction of the Administrator Signal er TOMINISTRA Acting Chief, Engineering and Manufacturing Branch (Title)

47.

## Every issue (1)

- January 11, 1979: Issued, Current. [certificate](https://openairdocs.org/files/sha256/e7/6e/e76e5111f642bc0f725e5615b97dc6e9f2872dc710f013f21887c3743925e00d)

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