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• 2007-01-04 21:14 Signaleer 504×157×??? (27573 bytes) In 1907, the French inventor Paul Cornu made a helicopter that used two 20-foot (6-meter) counter-rotating rotors driven by a 24-hp (18-kW) Antoinette engine. It lifted its inventor to about five feet (1.5 meters) and remained aloft one minute. ==Source=