In 1921, Russian engineer George de Bothezat was awarded a contract by the U.S. Army Air Corps to develop what would be the first American military helicopter to take flight.
De Bothezat flew the 10 ft tall, 65 ft long quadcopter for the first time at McCook Field near Dayton, Ohio, in 1922. Although the first flight only lasted 90 seconds the experiment allowed De Bothezat and his team to test different techniques that would lead to over 100 test flights that could hold up to three passengers.
After a few years of constant re-engineering, the Air Service lost interest in the project.
Nearly 20 years later, Russian engineer Igor Sikorsky would build a helicopter that the military would actually use. His R-4 which was the first mass produced helicopter was used for combat rescues and was the only helicopter to serve in WWII.
Watch the videos below to learn more about both men