The H-5, originally designated the R-5 (H for Helicopter; R for Rotorcraft), was designed to provide a helicopter having greater useful load, endurance, speed, and service ceiling than the R-4. The development of the XR-5 officially began in April 1942 when the British Air Commission ordered two prototype helicopters. The U.S. Army Air Forces (AAF) caught on to the possibilities of an upgraded R-4 and in May 1942 the Air Material Command released funds for the construction of four XR-5's.
The XR-5 fuselage was more streamlined and slimmer than the R-4 and nearly the entire nose of the helicopter was covered in Plexiglas windows that allowed greater visibility. Initially the three main rotor blades consisted of a laminated wood spar with supporting wooden ribs covered with fabric. These blades were difficult to build, hard to balance and easily damaged by rain.
The first XR-5 of four ordered made its initial flight on August 18, 1943 flown by Sikorsky chief test pilot Les Morris. On September 13, 1943, the XR-5 lifted a pilot, observer, and eight passengers perched on the landing gear fairing and exceeded the military useful load requirement by 600 pounds. Lt. Col. Frank Gregory, head of the AAF helicopter program, was enthusiastic about the XR-5. He considered it more advanced than any other American helicopter developed up to that time. The fifth and final XR-5 ordered was accepted by the AAF and transferred to Wright Field for further development on September 30, 1944. In March 1944, the AAF ordered 26 YR-5As for service testing, and in February 1945, the first YR-5A was delivered. Although the AAF accepted R-5A helicopters before the end of World War II, these never reached operational units. A number of R-5 variants served until after the Korean War.
During its service life, the H-5 was used for rescue and mercy missions throughout the world. It gained its greatest fame, however, during the Korean War when it conducted thousands of medical evacuation (medevac) missions to evacuate wounded personnel from frontline areas and many rescue missions of pilots shot down behind enemy lines
More than 300 H-5s had been built by the time production was halted in 1951.
The YH-5A on display at the U.S. Air Force Museum, one of the 26 ordered in 1944, was obtained from Eglin AFB, Florida, in March 1955.
Main rotor diameter: 48 ft.
Tail rotor diameter: 8 ft. 5 in.
Fuselage Length: 41 ft. 2 in.
Height: 12 ft. 11 in.
Weight: 4,815 lbs. loaded
Engine: Pratt & Whitney R-985 of 450 hp.
Maximum speed: 90 mph.
Cruising speed: 70 mph.
Range: 280 miles
Service Ceiling: 10,000 ft.