I thought about going after the hamburger, but decided to opt for the helicopter.
First helicopter flights in the US were in 1922. It was built under a US Army contract by a Georges de Bothezat. By 1924, the French had an operating machine. By 1930, Italy and Belgium had joined in.
By 1935, the French were flying over an hour and covering over 25 miles.
And the Germans, of course, began to work on the problem as soon as they were able. FW had a sucessful machine by 1936. (Over 11,000 ft in altitude; it set a distance record of almost 150 miles. (This is the craft that is best known for the famous indoor flight by Hanna Reitsch)
The Germans had two different helicopers in production (1940) before the Americans did (1941).
Primary source here: http://www.enae.umd.edu/AGRC/Aero/history.html
I'm no expert on the subject but perhaps the key word left out of the "FAQ" is "practical" or "successful" helicopter flight as noted below:
From Airscooter.com
It was not until Sikorsky came along that the first practical helicopter, the single rotor VS-300, came into existence. The VS-300 was first flown on 14 September 1939 with Sikorsky himself as the test pilot. The original VS-300 was powered by a 75 HP engine. The aircraft's body was nothing more than an open cockpit with a welded steel tubing frame.
From the History of The Helicopter
scroll down to Sept. 14, 1939
And from National Helicopter Museum, Stratford, Conn.
Indeed, the 15-year-old museum is the only institution in the country devoted solely to the helicopter. Igor Sikorsky made helicopter history when he developed the first practical, and then the first production, helicopters in Stratford.
SAM! Where the hell are you?