Aerospace engineers at Sikorsky Aircraft Co., Stratford, Conn. (www.sikorsky.com), have been developing and testing the X2, a demonstrator aircraft that showcases new helicopter technologies. If all goes as planned, the advances should let tomorrow’s vertical-lift aircraft hover efficiently and still cruise at more than 250 knots, a world record for a helicopter. (The Westland Lynx set a record of 217 knots that has stood for 22 years.)
To simplify hardware but keep the most advanced controls, the two-seat X2 uses fly-by-wire controls that translate pilot inputs into signals for the rotor rpm, the high lift-to-drag blades, low-drag hub fairings, and an active vibration-control system. The craft is powered by a 1,362-shp CTS8000 turbine, a turboshaft engine developed jointly by Rolls-Royce and Honeywell. The engine turns two counterrotating sets of props, which means the tail rotor is no longer needed to counter torque inherent in a single set of rotors. So the “pusher prop” is now used to generate extra thrust.
Edited by Stephen J. Mraz
