# STC SA622NW

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: William G Joplin dba, United States
- Description: Installation of two Lycoming GO-485-C2B engines, Hartzell HC-82X2O-2A/V9333N propellers and associated systems
- Applied: February 24, 1978
- Status date: September 15, 1978
- Product: Aircraft, Small Airplane
- Certification basis: Part 21
- Data sheets: [TCDS A-734](https://openairdocs.org/tcds/A-734), [TCDS A-767](https://openairdocs.org/tcds/A-767)
- Certificate PDF: https://openairdocs.org/files/sha256/82/8b/828bc7481249154e0ae29d340523eeb2ac65f75b34ddc3be3e4f6da54de45492
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/C5DF4225F618D12F86257A40006FFEA4.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA622NW

## ADs that name it (0)

None.

## Approved models (2)

- Gulfstream American Corporation G-44 ([TCDS A-734](https://openairdocs.org/tcds/A-734))
- Univair Aircraft Corporation 108-1 ([TCDS A-767](https://openairdocs.org/tcds/A-767))

## What the certificate says

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

United States of America Department of Transportation Federal Aviation Administration Supplemental Type Certificate Number: SA622Nw This certificate issued to: William G. Joplin, dBA Part 4a of the CiviI Air Regulations:

Original Product - Type bertificate Numben: A-734 Make: Grumman Model: G-44 (Widgon) Description of Type Design Change: Installation of two Lycoming 60-485-C2B engines, Hartzell HC-82X20-2A/V9333N propellers and associated systems in accordance with Lockheed Aircraft Service, Inc. Master Drawing SPD-712116 as per Item 108A of T.C.

Data Sheet A-734.

This modification includes a Widgon Exhaust System in accordance with Air Transport Industries Report 78FS007D1 and Drawing No. 78FS007 (Rev. A).

Limitations and Conditions: Data pertaining to this modification are considered inadequate for duplication in other aircraft. This approval is limited to the installation in a Grumman G-44, Serial Number 1328 only. A Copy of this Certificate shall be maintained as part of the permanent records for the modified aircraft.

Intes/ application: February 24, 1978 Date Reissued:

Date of Issuance: September 15, 1978 Date Amended:

FEDERAL AVIATION By direc OP. Riggin Acting Chief, Engineering and Manufacturing Branch (I stle)

47.

## Every issue (2)

- September 15, 1978: Issued, Current. [certificate](https://openairdocs.org/files/sha256/82/8b/828bc7481249154e0ae29d340523eeb2ac65f75b34ddc3be3e4f6da54de45492)
- June 23, 1978: Issued, Current. [certificate](https://openairdocs.org/files/sha256/72/06/7206bffcd099dbf69973fe79a000abbc932eff264a19155cc90653c832dabf50)

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