Gustave de Ponton d'Amécourt (16 August 1825 – 20 January 1888, Trilport, France[1]) was a French inventor, archaeologist, and numismatist.

[2][3] The lineage traced back to Augustin de Ponton (1736–1808), a commissioner of the Navy and later inspector general of the king's farms, who married Louise Maille in 1768.

Gustave de Ponton d'Amécourt, an erudite who studied mathematics, Sanskrit, Greek, and Latin, was a numismatist and archaeologist.

Notably, he conducted extensive studies on Merovingian coins delivered to the Historical and Archaeological Society of Maine, of which he was a member.

He successfully invented one of the first prototypes of a helicopter by designing his "dear propeller [fr]" in 1861, with his friend Gabriel de La Landelle, an experimental small prototype of a "heavier-than-air [fr]" aerostat with counter-rotating rotor with two coaxial aerial propellers, and a bicarbonate steam engine[4][5] (whose boiler was one of the first uses of aluminum), inspired, among other things, by the aerial screw and the ornithopter from Leonardo da Vinci's manuscripts [fr] of the 1480s, the Chinese bamboo-copter of the 4th century,[6] and their early study prototypes of aerial propeller, the "spiralifers".