Sikorsky comes to Paris buoyed by its announcement of plans to develop a high speed helicopter harnessing coaxial rotor technology and capable of cruising at speeds of up to 250kt (460km/h).

Dubbed the X2, the demonstrator will be a tandem-seat machine, funded entirely by Sikorsky, but built by the company's Schweizer Aircraft subsidiary. It is expected to fly by the end of 2006.

The aircraft will be a single-engine design, powered by an LHTEC T800-801 turboshaft, which will drive the coaxial four-blade rotors and the tail-mounted propulsor. The counter-rotating design negates the need for a tailrotor.


A modified Schweizer 333 helicopter will fly before the end of the year to test the fly-by-wire flight control system.

In high speed configuration, one or more 'pusher props' form part of an integrated auxiliary propulsion system, which means that there is no requirement to reconfigure the aircraft during flight.

Sikorsky is applying 'X2' to a range of technologies including new rotor blade designs, advanced flight control laws, transmissions with greater horsepower-to-weight performance and active vibration control.

Although a production aircraft using the X2 technology suite is a long way off, Sikorsky envisages a number of markets using both manned and unmanned aircraft, with a design that can be scaled all the way from light civil helicopters through to the USA's Joint Heavy Lift rotorcraft.

Source: Flight Daily News