- A U.S. utility and training helicopter designed and manufactured by the Sikorsky Aircraft Division of United Aircraft Corporation from 1942 to 1944
- The world's first mass-produced helicopter and the first to enter U.S. and British military service
- Developed from the VS-300 helicopter, Sikorsky's first airworthy helicopter, with fabric-covered rear fuselage, side-by-side seating and dual controls
- Exceeded all previous records for helicopter endurance, altitude and airspeed
- A U.S. Coast Guard R-4 made the first recorded helicopter rescue mission, in 1944
- A U.S. Coast Guard R-4 made the first helicopter rescue in Canada (in an inaccessible area 200 kilometres from Goose Bay, Labrador), in May 1945
- First flight was on January 4, 1942 (XR-4)
Following a demonstration of his VS-300 helicopter in 1939, Igor Sikorsky won a contract for development of the XR-4 which retained the single rotor of the VS-300 but had a covered fuselage, side-by-side seating and dual controls. The flying controls in the XR-4 set the standard for all subsequent helicopters. The XR-4 was re-engined in 1943 and called XR-4C. Service trials with the YR-4A and YR-4B, including one from a tanker, resulted in the final variant, the R-4B. One hundred R-4Bs were made with 45 going to Britain.
This aircraft was the first helicopter produced for the US Air Force, and the world’s first mass-produced helicopter. The first helicopter rescue in Canada occurred when a US Coast Guard R-4 picked up the crew of a Canso that had crashed 482 km (300 miles) southwest of Goose Bay, Labrador.
Reserve Hangar, Canada Aviation and Space Museum
Exchange with the Planes of Fame Museum, United States
The Sikorsky Aircraft Division of United Aircraft Corporation built this R-4 for the U.S. Army Air Forces in 1944. Its subsequent history is not known. The Museum acquired it from the Planes of Fame Air Museum in Chino, California in 1983, in exchange for a Japanese aircraft. The R-4 does not have an engine.
|Rotor diameter:||11.6 m (38 ft)|
|Length||10.8 m (35 ft 5 in)|
|Height||3.8 m (12 ft 5 in)|
|Weight, Empty||916 kg (2,020 lb)|
|Weight, Gross||1,150 kg (2,535 lb)|
|Cruising Speed||104 km/h (65 mph)|
|Max Speed||131 km/h (81 mph)|
|Rate of Climb||198 m (650 ft) /min|
|Service Ceiling||2,440 m (8,000 ft)|
|Range||370 km (230 mi)|
|Power Plant||one Warner R-550-3, 200 hp, 7-cylinder, fan-cooled, radial engine|