Sikorsky's X2 Technology demonstrator is back in the air, modified and ready to begin high-speed flight testing with the goal of achieving 250kt. Two flights totalling an hour on June 30 included the first full engagement of the tail-mounted propulsor.
Driven from the same T800 engine as the rotors, the variable-pitch propulsor is one of the "X2 technologies". The others include the rigid counter-rotating rotors with their low-drag hubs, fly-by-wire flight controls and active vibration control. Sikorsky quotes chief test pilot Kevin Bredenbeck as saying noise and vibration were "very low" on the June 30 flights, which reached 52kt.
Compare with X2 with Sikorsky's XH-59, which used the same advancing-blade rotor concept, and you can see what changes 20 years of technology development have wrought.
Photo: 1000aircraftphotos.com, Johan Visschedijk Collection
The XH-59 was fast, but it was also noisy, shaky, draggy and thirsty. It needed two pilots and four engines to do what the X2 can do with one pilot and one engine. Or promises to. Sikorsky is running a bit behind schedule, but says it still plans to reach 250 kt by year-end.