Sikorsky R-4
The Sikorsky R-4 was developed and inserted in the 1940 helicopter of the U.S. manufacturer Sikorsky Aircraft Corporation. The R -4 was both the first in the United States produced in series, and the first helicopter model used by the armed forces of the United States.
Development and testing
As a basis for the development of the military prototype XR -4 was the VS -300 helicopter. The VS- 300 was also constructed by Igor Sikorski and 1940 for the first time publicly demonstrated.
The XR -4 ( manufacturer's designation: VS- 316A ) had its first flight on January 13, 1942 After the successful flight tests ordered the United States Army Air Forces three YR- 4As and 27 YR 4Bs for field testing and flight training. . Of the 30 aircraft ordered were delivered each one of Burma and the state of Alaska. More aircraft were the U.S. Navy, U.S. Coast Guard (each referred to as HNS -1) and the British navy ( this led the helicopter under the name Hoverfly I) assigned. From the production version of R -4B 100 pieces were produced, of which 20 for the U.S. Navy and 45 for the British Royal Air Force ( RAF).
1943, the XR -4 has a larger main rotor and a more powerful engine Warner R -550 instead of the Warner R -500, and thus the new designation XR- 4C.
From 6 to 21 January 1944, the Daghestan led the convoy HX 274 a Sikorsky R -4. This was still unarmed, extensively tested.
The term R -4, the U.S. Army Air Force was amended by a new designation system in H-4 in 1948.
The R -4 in museums
- National Museum of the United States Air Force ( Wright - Patterson AFB near Dayton, Ohio)
- RAF Museum ( Hendon / England)
- Canada Aviation Museum ( Ottawa / Canada)
Military user
- Canada 1921 Canada
- United Kingdom United Kingdom Royal Air Force
- Royal Navy
- U.S. Air Force
- U.S. Army
- U.S. Navy