- Boeing will continue refining its Phantom Swift X-Plane design for the Pentagon
- The programme is geared at demonstrating efficient hover and high-speed flight
Boeing has been awarded a USD9.4 million contract modification to continue refining its design of the experimental vertical take-off and landing (VTOL) Phantom Swift X-Plane, according to a 26 August Department of Defense (DoD) announcement.
The DoD's Defense Advanced Research Projects Agency (DARPA) awarded the funds for a 16-month option on an existing 7-month base contract, according to the announcement.
"Boeing will continue to refine their design of the [VTOL] experimental aircraft, bringing it to a preliminary design review level," the DoD said. "Specifically, Boeing will complete the following milestones: system definition review; interim progress review; and preliminary design review."
Most of the work is to be performed at Boeing's Ridley Park, Pennsylvania, facility, according to the announcement.
Last year, Boeing's Phantom Works division used rapid prototyping and additive manufacturing techniques, such as three-dimensional printing, to quickly design, build, and fly a scaled-down (17% of planned size) Phantom Swift, the company had said in a statement.
DARPA in July performed conceptual design reviews of the four VTOL X-Plane contenders: Aurora Flight Sciences; Boeing; Karem; and Sikorsky. The competitors had received Phase 1 contracts for the USD130 million programme in 2013. The 26 August award to Boeing is considered a Phase 1B extension, company spokewoman Deborah VanNierop told IHS Jane's . Phase 2 and Phase 3 were planned as a downselect to one platform followed by further development with the goal of flight trials in the 2017-18 timeframe, respectively.
As of this writing DARPA had not responded to requests for confirmation of the schedule as defined at the programme's outset.
The agency did not specify whether the aircraft was to be manned or unmanned, but all entrants opted for unmanned platforms. However, there is potential for the full-scale Phantom Swift to be manned, and Boeing officials have said that they envisage a whole family of platforms based on the design.
The VTOL X-Plane programme is geared towards demonstrating efficient hover and high-speed flight. The specific requirements are that the aircraft achieve a top sustained speed of 300-400 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 5-6; and carry a useful load of at least 40% of the vehicle's projected gross weight of 10,000-12,000 lb (4,500-5,450 kg).
Of the four contenders, Boeing's Phantom Swift is the only one to have been built (as a scale model) and flown.
Phantom Swift employs ducted-fan technology. The company has devised a unique combination of body fans and tilt-wing fans for improved control. In its full-sized configuration the Phantom Swift will measure 15.2 m (50 ft) from wingtip to wingtip, 13.4 m from nose to tail, and will weigh up to 5,450 kg.
With two downward facing fans in the main body of the aircraft for vertical lift, payloads would be housed in bays in the nose, mid-section, and tail of the aircraft. In high-speed cruise the lift fans are shut down and doors are closed for greater aerodynamic performance (forward propulsion is provided by the wingtip thrusters).
While the demonstrator will be powered by a conventional General Electric CT7-8 engine, according to Boeing, the long-term plan is to incorporate an all-electric drive as soon as the technology makes it feasible.
- DARPA to progress VTOL X-Plane as Boeing reveals Phantom Swift details
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