Clark Bi-wing Ornithopter
James W. Clark of Bridgewater, Pennsylvania, supposedly tested this machine between 1900 and 1910. It failed to fly, was wrecked, then rebuilt and fitted with its present engine – a 5 hp 2-cylinder Waterman – in 1907.
Currently residing at the Owls Head Transportation Museum in Maine, possibly the oldest full-sized internal combustion engine powered flying machine anywhere in the world.