Clément Ader

Clément Ader Avion III

The Clément Ader Avion III, built in 1897 by French engineer and inventor Clément Ader, was the culmination of his early attempts to achieve powered, heavier‑than‑air flight. Following the ill‑fated Avion I (1890) and the partially successful Avion II (1897), Ader designed the third machine as a twin‑propeller, steam‑driven monoplane with a 30‑horsepower Éole engine, one of the first purpose‑built aviation powerplants. Its wingspan of 13 metres and triangular planform gave the aircraft a pronounced dihedral, while the fuselage featured a wooden lattice framework covered with canvas, typical of the era. The twin propellers were mounted on a central shaft and turned in opposite directions, a concept intended to cancel torque and improve stability.

On 14 October 1897 Ader claimed that the Avion III made a brief, uncontrolled hop of about 100 metres, an event that, if true, would pre‑date the Wright brothers’ flight by several years. Though contemporary witnesses disputed the distance and control, the aircraft demonstrated the feasibility of steam propulsion and twin‑propeller arrangements, influencing later designers. The Avion III stands as a landmark in the transition from speculative experiments to systematic engineering in early aviation, marking Clément Ader’s lasting contribution to the quest for powered flight.

Classification

Dimensions

Length
5.2 metre
Height
3.5 metre
Wingspan
15 metre
Mass
258 kilogram

Production & History

Units Produced
1
First Flight
1897

Design & Classification

Manufacturer
Clément Ader
Engine
steam engine
Wikidata ID
Q356358