One notable test performed with the RSRA was the use of the main and tail rotor load measurement system to determine the vertical drag of the airframe. The joint NASA/Army project began in December 1970, first flight on Octowith the first of two aircraft arriving from Sikorsky to NASA on February 11, 1979. The RSRA was a unique pure research aircraft developed to fill the void between design analysis, wind tunnel testing, and flight results of rotor aircraft.

This system, when activated, fired explosive bolts that severed the main rotor blades, escape panels were blown off the roof of the aircraft, then the crew was extracted using rockets. Unique among helicopters of its time, it was fitted with a crew emergency extraction system. In addition, it could fly as a fixed-wing aircraft without a main rotor. The RSRA could be fitted with TF34 turbofans and wings to allow compound helicopter configurations to be experimentally investigated at speeds up to 300 knots (560В km/h). The airframe was developed using an existing Sikorsky S-61 main rotor, an S-61 roller gearbox, and a highly modified Sikorsky S-67 airframe. The RSRA was developed to allow the inflight measurement of helicopter rotor characteristics.

The Rotor Systems Research Aircraft (RSRA) was developed by Sikorsky for NASA and the Army.

X wing cockpit