The Nelson H-44 is an American single ignition, four-cylinder, horizontally opposed, direct drive, two-stroke aircraft engine that was developed by the Nelson Engine Company for use in motorgliders.
[1] The H-44 was designed in the period following the Second World War and a specially designed motor glider was created by Hawley Bowlus to utilize the engine, the Bowlus/Nelson Dragonfly.
[1] The four-cylinder engine runs on a 12:1 mixture of 80 octane gasoline and SAE 30 oil.
It is equipped with a single Carter WA1 carburetor and a recoil starter.
[1] Employed in the Dragonfly the H-44 proved underpowered, which led to the design of the H-49 version.