Manly–Balzer engine

The Manly–Balzer was the first purpose-designed aircraft engine, built in 1901 for the Langley Aerodrome project. The engine was originally ordered from Stephen Balzer (1864–1940) in New York, but his five-cylinder radial engine design failed to live up to its claims. Langley's chief assistant, Charles Manly, then reworked the engine to produce a design that held the record for power-to-weight ratio for any engine for many years. Manly later worked for Glenn Curtiss, and was one of the team-members who designed the mass-produced Curtiss OX-5.