Boeing and Karem named as latest VTOL X-Plane contenders
Gareth Jennings, London
18 March 2014
DARPA's VTOL Experimental Plane (VTOL X-Plane) programme seeks to enable radical improvements in vertical take-off and landing flight through cross-pollination between the fixed-wing and rotary-wing worlds. DARPA has awarded prime contracts for Phase 1 of VTOL X-Plane to Aurora Flight Sciences, Boeing, Karem Aircraft and Sikorsky. Three of the four—Boeing (top), Karem Aircraft (middle) and Sikorsky (bottom)—provided concept images of their proposed designs. (DARPA)
Boeing and Karem have been officially added to the list of companies awarded contracts under the Defense Advanced Research Projects Agency (DARPA) vertical take-off and landing (VTOL) X-Plane programme, the agency announced on 18 March.
The companies join Aurora Flight Sciences, and Sikorsky in being awarded Phase 1 contract to cross-pollinate the best of fixed- and rotary-winged aircraft with the goal of improving vertical and cruise flight capabilities. No value was disclosed, though the overall programme is expected to be worth USD130 million.
According to the agency, the VTOL X-Plane demonstrator should achieve a top sustained flight speed of 300 kt to 400 kt; raise aircraft hover efficiency from 60% to at least 75%; present a more favourable cruise lift-to-drag ratio of at least 10, up from the current 5 to 6; and carry a useful load of at least 40% of the vehicle's projected gross weight of 10,000-12,000 lb (4,500 kg to 5,450 kg).
"The technologies that VTOL X-Plane intends to develop [should] apply equally well to manned [and unmanned] aircraft. Another common element among the designs is that they all incorporate multipurpose technologies to varying degrees. Multipurpose technologies decrease the number of systems in a vehicle andits overall mechanical complexity. Multipurpose technologies also use space and weight more efficiently to improve performance and enable new andimproved capabilities," DARPA said.
With the Phase 1 contracts now awarded, the four participants are required to submit their preliminary designs for review by DARPA in late 2015. A downselect to one design will be made for Phase 2 and Phase 3, with flight trials scheduled for the 2017 - 2018 timeframe.