s of Clement Ader's
Éole. '' (1897 photograph). Following his work with V8 engines, Ader turned to the problem of mechanical flight and until the end of his life gave much time and money to this. Using the studies of
Louis Pierre Mouillard (1834–1897) on the flight of birds, he constructed his first flying machine in 1886, the
Ader Éole. It was a bat-like design run by a lightweight
steam engine of his own invention, with 4 cylinders with a
power rating of , driving a four-blade
propeller. The engine weighed . The wings had a span of . All-up weight was . On 9 October 1890 Ader attempted to fly the
Éole. Aviation historians give credit to this effort as a powered take-off and uncontrolled flight in
ground effect of approximately at a height of approximately . Ader also claimed credit for getting off the ground in the Éole. Ader began construction of a second aircraft he called the
Avion II, also referred to as the
Zephyr or
Éole II. Most sources agree that work on this aircraft was never completed, and it was abandoned in favour of the
Avion III. Ader's later claim that he flew the
Avion II in August 1892 for a distance of in
Satory near Paris, was never widely accepted. == Book on aviation ==