Two and four cylinder engines based on the German Volkswagen car engine.

-At first the Hummel Aviation factory was located in Bryan, OH. It is currently in the new location of Coolidge, AZ.

-The two-cylinder engine is a Half-VW, giving 37 hp at 3,000 rpm. It is known as the "1/2 VW". Below we show a photograph of this engine.

“Hummel twin-cylinder”

-In the first photograph we see the two-cylinder engine. It is a Volkswagen engine of which only the two front cylinders are used.

-The spaces for the rear cylinders are covered with individual cover plates.

“Hummel two-cylinder engine”

-It uses a Slick magneto with simple ignition. We can see the two output cables.

-The two-cylinder engines are offered with 28, 32, 37 and 45 hp according to accessories.

“Hummel 4-cylinder engine”

-The four-cylinder engines are offered with the possibility of double magneto and powers ranging from 50, 60, 76 to 85 hp depending on version.

From Appendix 10: Below we show another two-cylinder Hummel based on the cutting of an automotive Volkswagen engine. We see the two front cylinders with the heads cut in half. The block and crankshaft too. A single magneto at the rear mounted on a plate directly on the engine, supplying two sparks for the two spark plugs.

“Hummel 2-cylinder front view”