Heath-Henderson B-4

Heath-Henderson B-4
Heath-Henderson B-4 aircraft engine on display at the Steven F. Udvar-Hazy Center
Type	Piston aero engine
National origin	United States
Manufacturer	Heath-Henderson
First run	1930?
Major applications	Heath V Parasol
Unit cost	$300 in 1932

The Heath-Henderson B-4 engine was a motorcycle piston engine modified for use in aircraft.

"The Heath Airplane Company's Model B-4 was an in-line, four-cylinder, air-cooled Henderson motorcycle engine converted for use in aircraft by modifying the lubrication system and the valves. The B-4 mainly powered the small and economical Heath Parasol monoplane, which Heath sold in kit form for homebuilders in the 1920s and '30s."

"The low-cost, reliable Henderson motorcycle engine was well-suited for the Heath airplane design because it helped make sport flying affordable for many people. Service was simple and economical because parts were cheap and easy to obtain throughout the country."

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Wikipedia