# STC SA684NW

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: Nagel, Jack E., United States
- Description: Installation of a McCauley propeller on a Franklin engine
- Applied: August 18, 1978
- Status date: July 20, 1988
- Product: Aircraft, Small Airplane
- Certification basis: Part 21
- Data sheets: [TCDS A-766](https://openairdocs.org/tcds/A-766)
- Certificate PDF: https://openairdocs.org/files/sha256/12/5c/125cebc8e32e8ee95647145226f0d4ebac6ec102ea6829f5437336e3a0155c2d
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/0E7529FB9729AE1C86257A4600479BF6.0001
- DRS record last changed: December 5, 2025
- Page: https://openairdocs.org/stc/SA684NW

## ADs that name it (0)

None.

## Approved models (1)

- Swift Museum Foundation Inc. GC-1B ([TCDS A-766](https://openairdocs.org/tcds/A-766))

## 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 SA684NW This certificate issued to: Jack E. Nagel Part 42 4 the Civil Air Frequelations.

Original Product - Type-Pertificate Number: A-766 Make: Universal Aircraft Industries Make: GIobe GC-1B Description of Type Design Change: . Installation of a McCauley 2A31C21/84SF-10 propeller on a Franklin 6A-350-Cl engine in accordance with Jack E. Nagel photograph 1.

Limitations and Conditions: Data pertaining to this modification are considered inadequate for duplication in other aircraft. This approval is limited to the installation in Universal Aircraft Industries, Globe model GC-1B aircraft, Serial Number 1115 only. A copy of this Certificate and Continuation Sheet must be maintained as part of the permanent records for the modified aircraft.

allowable Oil Inlet: 240°F Max. allowable Propeller: McCauley 2A31C21/84SF-10 Propeller Limits: 220 HP and 2800 RPM Serial Number Eligible: 1115 Air Speed Limits: No change.

Maximum Weight: 1970 1bs.

C.G. Limits: (+29.6) to (+33.5) at 1970 1bs.

Powerplant Instrument Markings: Radial red line at 2800 RPM Airspeed Markings: No change.

- END -

47.

## Every issue (1)

- July 20, 1988: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/12/5c/125cebc8e32e8ee95647145226f0d4ebac6ec102ea6829f5437336e3a0155c2d)

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