Sikorsky is targeting the third quarter to achieve the 250kt (460km/h) goal for its X2 high-speed prototype, after several delays in the flight-test programme.
Twenty months after first flight, Sikorsky expects to complete the tenth flight in the coaxial rotor aircraft's test programme during the week of 19 April, says Jim Kagdis, Sikorsky director for advanced programmes.
Sikorsky intends to increase the speed by 20kt increments in each flight test, with 150kt the goal for the 10th flight, he says. Follow-on flight tests are expected to occur every three weeks.
A gearbox manufacturing problem halted flight tests after December 2009. The key component for the LHTEC T800 turboshaft-powered counter-rotating coaxial pusher system has since been repaired and overhauled, Kagdis says.
© Ahsish Bagai/Sikorsky
The X2 is Sikorsky's bid to usher in a breakthrough in helicopter performance. By integrating modern flight controls and vibration cancellation systems, Sikorsky believes it can overcome the challenges faced by similar high-speed rotorcraft systems attempted in the 1970s.
Although the flight-test programme has encountered problems, Kagdis notes that none of the issues have changed Sikorsky's expectations. "We have not found anything that tells us that we can't get out to a higher speed," he says.
Sikorsky intends to offer the X2 initially for the US Army's potential competition to replace the Bell OH-58D Kiowa Warrior. A production version of the high-speed aircraft could be available in 2018.
The army is conducting a mandatory analysis of alternatives until December or January. Its key dilemma is whether to invest in a new airframe using existing technology, or wait several years for a next-generation leap in technology, says Maj Gen Jeffrey Schloesser, director of army aviation. "That decision is not ready to be made," he adds.