You gotta remember the helicopters back then were prototypes. They had a Japanese helicopter that could carry a torpedo or a depth charge and it could launch off carriers. By the time they said we'll make them America bombed all there factories. That's the only WWII helicopter I know of though.
The Ka-1 was technically an autogyro in that it used an unpowered rotor to provide lift and an engine-powered propellor to provide thrust.
The Fa 233 helicopter was used by the Luftwaffe to transport supplies and troops, think mostly used in mountainous areas and only 20 were manufactured. The US has the Sikorsky R-4 helicopter that was the first helicopter to be used in a combat rescue operation in the CBI theater in 1944.
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