Blended wing body research aircraft flies for the first time

The modified X-48C blended wing body (BWB) research aircraft flew for the first time on 7 August from NASA’s Dryden Flight Research Center at Edwards Air Force Base in California.

Designed by Boeing and built by Cranfield Aerospace in the UK, the unmanned X-48C aircraft took off at 07:56 PDT and climbed to an altitude of 5,500ft (1,676m) before landing nine minutes later.

According to Boeing, the X-48C is a scale model of a heavy-lift subsonic vehicle that forgoes conventional tube-and-wing aircraft design in favour of a triangular aircraft that blends the vehicle’s wing and body.

Boeing and NASA believe the BWB concept offers the potential over the long term of significantly greater fuel efficiency, consuming at least 20 per cent less fuel compared with conventional subsonic aircraft. The design of the BWB means also that it is 50dB less noisy on approaching an airport.

‘Working with NASA, we are very pleased to enter into the next flight-test phase of our work to explore and validate the aerodynamic characteristics and efficiencies of the BWB concept,’ said Bob Liebeck, a Boeing senior technical fellow and the company’s BWB programme manager.

‘In our earlier flight testing of the X-48B, we proved that a BWB aircraft can be controlled as effectively as a conventional tube-and-wing aircraft during take-offs and landings, and other low-speed segments of the flight regime,’ he added. ‘With the X-48C, we will be evaluating the impact of noise-shielding concepts on low-speed flight characteristics.’

The X-48C is a modified version of the X-48B aircraft, which flew 92 times at NASA Dryden between 2007 and 2010. The X-48C is configured with two 89lb thrust turbojet engines, instead of the three 50lb thrust engines on the B model; and wingtip winglets have been relocated in board next to the engines on the C model, effectively turning them into twin tails. The aft deck has also been extended about 2ft at the rear.

Engineers from Boeing Research & Technology will be working with NASA engineers during flight tests of the X-48C, which are expected to continue throughout 2012. As handling qualities of the X-48C will be different from those of the X-48B, the project team has developed flight control software modifications, including flight-control limiters to keep the craft flying within a safe flight envelope.

With a 21ft wingspan, the 500lb aircraft is an 8.5 per cent scale model of a heavy-lift subsonic aircraft with a 240ft wingspan that could possibly be developed in the next 15–20 years for military applications such as aerial refuelling and cargo missions.

Boeing and NASA’s Aeronautics Research Mission Directorate are funding X-48 technology demonstration research. The effort supports NASA’s Environmentally Responsible Aviation project, which aims to reduce the fuel burn, emissions and noise of future aircraft.

We’ve been made aware that some of you are having difficulty viewing the video of the X-48C’s maiden flight. The flight can be viewed by clicking here.