Franklin O-335 Explained

The Franklin O-335 (company designations variations on 6A and 6V) was an American air-cooled aircraft engine of the 1940s. The engine was of six-cylinder, horizontally-opposed layout and displaced 335abbr=onNaNabbr=on. The power output of later variants was 225abbr=onNaNabbr=on.

Design and development

These engines were commonly vertically mounted and used to power many early helicopters in the United States. They were closely related to the 2A4 and 4A4 2- and 4-cylinder engines. In various subtypes, the 6A4 remained in continuous production from 1945 to the time Franklin's United States operations ceased in 1975, with versions continuing in Polish production into the 1990s.

In 1947 this engine was modified into a water-cooled version by the Tucker Car Corporation for use in the 1948 Tucker Sedan. Tucker liked the engine so much that he purchased the Aircooled Motors/Franklin Engine Company, and it remained under the ownership of the Tucker family until 1961.

Variants

O-335-1:Military designation of vertical installation model for helicopters :175abbr=onNaNabbr=on

References

Gunston, Bill. (1986) World Encyclopedia of Aero Engines. Patrick Stephens: Wellingborough. p. 57
Erickson, Jack. Horizontally Opposed Piston Aero Engines
Book: Wilkinson, Paul H.. Aircraft Engines of the world 1945. 1945. Paul H. Wilkinson. New York. 80–81.
US Department of Transportation Federal Aviation Administration Type Certificate Data Sheet E-238 Revision 12, December 8, 1994.