Sikorsky HR2S-1 Mojave

Sikorsky Aircraft Corporation · USA · first flew 1953 · helicopter

The HR2S-1 Mojave was the US Navy designation for the Sikorsky S-56, the largest and most powerful piston-engine helicopter of its era, designed to carry heavy equipment and large numbers of troops for assault operations. It was a significant leap in helicopter capability.

Recognition (WEFT)

W — WingsHigh-mounted, rotary
E — Engines2 × piston, fuselage-mounted
F — Fuselage21.5 m fuselage
T — TailNo tailplane

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Very large helicopter with twin piston engine sponsons flanking a broad fuselage, clamshell nose loading doors, five-bladed main rotor, and retractable undercarriage — the largest single-rotor piston helicopter ever built.

Specifications

Figures are for the representative variant described above; marks differ. See how AircraftIQ sources figures.

History

The S-56 first flew in 1953 and entered Marine Corps service as the HR2S-1 and Army service as the H-37 Mojave. The design featured two radial piston engines mounted in sponsons on either side of the fuselage, driving a single five-bladed main rotor. The clamshell nose doors allowed direct loading of vehicles and artillery.

Variants

The HR2S-1 was the Navy/Marine Corps version; the Army operated it as the H-37A and H-37B Mojave. A turbine-powered development was proposed but not built.

Where you'll see it

Served with the US Marine Corps and Army in the late 1950s and early 1960s for heavy-lift assault operations; used in the early stages of US involvement in Vietnam before being replaced by the CH-47 Chinook.

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