Sikorsky's X2 Technology Demonstrator that first took to the air on August 27, 2008 has flown for the last time. The 23rd and final flight was conducted in the early morning of July 14, 2011 from Sikorsky's new Innovations Center in West Palm Beach, Florida. In flight tests carried out over the three-year period, the X2 flew a total of around 22 hours and on September 15, 2010 achieved a maximum cruise speed of 253 knots in level flight - an unofficial record for a conventional helicopter. While the X2 is now officially entering retirement, the lessons learned and technologies developed for the X2 program will pave the way for Sikorsky's S-97 Raider helicopter.
Sikorsky first announced its intention to develop the X2 Technology Demonstrator using a coaxial rotor design in 2005, with the aim of demonstrating that a helicopter can cruise comfortably at 250 knots without sacrificing low speed maneuverability and hover capabilities and with the ability to transition from low to high speeds seamlessly. Sikorsky says the X2 program has now proven its design ticks all those boxes, while helping to develop the next generation of Sikorsky engineers, some of who are now working on the S-97 Raider program and the Firefly electric helicopter program.
The company says the S-97 Raider program will design, build and fly two prototype light tactical helicopters to allow the U.S. military to evaluate the viability of a fast and maneuverable next-generation rotorcraft for a variety of combat missions. Like the X2 demonstrator, the S-97 Raider will feature twin coaxial counter-rotating main rotors and a pusher propeller that enables an X2-designed helicopter to cruise at 220 knots, fly-by-wire flight controls, hub drag reduction, active vibration control, and an integrated auxiliary propulsion system.
"This program will produce two prototype assault/attack aircraft with six passenger cabins and the ability to carry armament," said Mark Miller, Sikorsky Vice President of Research & Engineering. "In addition to the superior speed and maneuverability of X2 technology, these aircraft are designed to be capable of 10,000-foot hover out of ground effect on a 95-degree (35° Celsius) day."
At the final flight of the X2 Technology demonstrator, Sikorsky President Jeffrey Pino said, "This flight is the culmination of a five-year, internally funded program to expand the operational envelope of helicopters. The results of this program speak to the success of a rapid prototyping environment, where a small empowered team was able to meet a specific number of very challenging goals. We met these within a small budget and a compressed schedule."