Sikorsky S-72

Sikorsky Aircraft Corporation · United States · first flew 1976 · helicopter

The Sikorsky S-72 Rotor Systems Research Aircraft (RSRA) was an experimental compound helicopter developed for NASA and the US Army to test advanced rotor configurations at high speed, first flown in 1976.

Recognition (WEFT)

W — Wings	High-mounted, rotary
E — Engines	2 × turboshaft, fuselage-mounted
F — Fuselage	23.139 m fuselage
T — Tail	Conventional

WEFT is AircraftIQ's four-point recognition method — how it works.

Spot it by:

Experimental compound helicopter / RSRA research aircraft
Standard helicopter rotor plus stub wings and tail-mounted jet engines
NASA/US Army Rotor Systems Research Aircraft

Resembles a large utility helicopter but carries prominent stub wings midway along the fuselage and has a more angular body than standard utility helicopters; additional jet engine pods may be fitted for compound flight research.

Specifications

The Sikorsky S-72 has a length of 23.139 m (76 ft).
It has a wingspan of 13.746 m (45 ft).
Typical crew: 2.

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

History

Two S-72 RSRA aircraft were built under a NASA/Army contract to serve as variable-configuration flying testbeds. The aircraft could be flown as a conventional helicopter, a compound helicopter with stub wings and auxiliary thrust, or theoretically as a fixed-wing aircraft with rotor removed. One aircraft was later modified with X-wing rotor-wing blades for the X-wing programme, which was cancelled in 1988.

Variants

The S-72 RSRA (two aircraft) and the proposed X-wing variant (heavily modified); both programmes are completed.

Where you'll see it

Operated by NASA Ames Research Center and the US Army for rotor research; never a production type.

Related aircraft

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