Sikorsky R-4
Sikorsky R-4 of the Fleet Air Arm.
Role	Helicopter
National origin	USA
Manufacturer	Sikorsky.
First flight	1942
Introduction	1943
Status	Out of order
Primary user	United States Army Air Force
Number built	131 examples.

The Sikorsky R-4 is the first military helicopter built in USA. It flown during World War II and beginning of Korea War. Some were used by US Navy, US Coast Guard and Fleet Air Arm.

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-KOREAN WAR-

The R-4 was used in Korea as a rescue helicopter helping to carry wounded troops to military hospitals. Sikorsky said his greatest accomplishment with the helicopter, even better than making more space for air fields was the tens of thousands of live his invention saved through the multitude of wars it was deployed in.