[1] Most sources agree that work on it was never completed, Ader abandoning it in favour of the Avion III that had a financial backer.

Ader's later claim that he flew the Avion II in August 1892 for a distance of 100 m at a field in Satory is not widely accepted.

[citation needed] The name "Avion" was devised by Ader from Latin avis ("bird") and became the origin of the word avion, the most common in French to designate an airplane (heavier-than-air aircraft).

[citation needed] The engine developed for Avion II, called Zéphyr was a light steam engine driving a 3 m (10 ft) diameter 4-bladed propeller, in which steam was cooled through a condenser.

It yielded 22 kW (30 hp) at 480 rpm at a pressure of 15 Pa (0.00 psi), weighing 33 kg (73 lb) dry, and 134 kg (295 lb) with full boiler and accessories.