It is the Heath Aerial Vehicle Co., sometimes known as Heath AV Co. and by mistake Heath "Aviation" Co.

-But the topic does not end here. The founder was pioneer pilot, designer and builder Edwards B. Heath.

-In 1909 he made a 25 hp two-cylinder. But in 1910 the company is known as Heath Airplane Corp, in Chicago. Later International Aircraft Corp, in Niles, MI.

-In 1918 he made the 4-B, a water-cooled, 4-cylinder, in-line engine that gave 75 hp. The same year this gave way to the 4-C that had the same arrangement, but gave 40-60 hp.

-Without a doubt the most characteristic engine of this brand is the Henderson motorcycle-engine adaptation that would give way to the B-4 in 1926. It gave 25 hp.

-It had a displacement of 83 cu. in. and four in-line, upright, air-cooled cylinders. Successive modifications by others would result in the Heath-Henderson or Heath-Cleveland.

“Heath, Henderson basis”

-By 1912, Heath bought Bates, also from Chicago, so horizontally-opposed, two-cylinder engines appear as Heath, being those contributed by Bates, like the C-2 of 1919 that gave 25 hp. You can see this engine at the "Seattle Museum of Flight"

-The C-3 was from 1919 as well, and gave 40 hp. It had three radial cylinders.

-The C-6 with 6 radial cylinders gave 80 hp.

-In a publication there is mentioned a Heath 12-cylinder V-engine that gave 200 hp and was water cooled.

-Heath made a horizontally-opposed, 2-cylinder engine that appears below on an airplane made by the same constructor.

-Possibly it is a Bates engine.

-It is the Heath 2B plane with the engine that is also called Heath 2B.

“Photo from 1919 with a Heath 2B”

-The photo is credited to Jim Jacobson

-But it surprises us when we only related the brand with the construction or better said adaptation of Henderson motorcycle engines.

-See Heath-Henderson.

-In fact it is mentioned in the main text that there was a 25 hp, two-cylinder engine, that is supposed to be the Heath 2B

-The Heath Airplane Co. modified a Thor Model 15A motorcycle engine in the year 1922.

-It had two cylinders in V and gave 20 hp with gear.

-As a curiosity in the summer heat they added another small propeller to the main one to cool the engine.

-See something similar in the BMW chapter.

From Appendix 6: It is the Heath Airplane Co. that adapts Henderson motorcycle engines (see main text). We found some of ads of the time -round 1925-. The price of the engine was about $ 250.

“Heath ads”

-We see in detail the aeronautical conversion of the Henderson motorcycle engine.

“Heath-Henderson conversion”