Retaining the same bat-like configuration of the Éole, the Avion III was equipped with two engines driving two propellers.

While the earlier aircraft had no means of directional control at all, this one was equipped with a rudder.

Trials began at the Satory army base near Versailles on 12 October 1897, with the aircraft taxiing along a circular track.

On 14 October 1897, it left the track, turned halfway around, and then stopped, but did not take flight.

[1] Later in his life, Ader claimed that there had been a flight of 100 m (328 ft) on this day, and said he had two witnesses to confirm it.