4 amazing pioneering aircraft

Ornithopter
Leonardo da Vinci designed a bird-like flying machine known as an ornithopter. It’s unknown if he ever constructed his sketch, but a heavily adapted modern version, the Snowbird, is capable of flight.

‘Bat’ monoplane
In 1890 French engineer Clément Ader invented a steam-powered aircraft 13 years before the Wright brothers’ first flight. It could only fly just off the ground and for a distance of around 50m (160ft).

Giffard dirigible
The powered airship was invented by French engineer Henri Giffard in 1852. This lighter-than-air craft was filled with hydrogen, propelled by a steam engine and steered using a sail-like rudder.

NASA AD-1
This unusual aircraft, first flown by NASA in 1979, proved that aircraft wings could be pivoted in-flight and that, at high speeds, turning the wings reduces drag and improves
flight performance.