Boeing has chosen an old McDonnell-Douglas airliner as the test bed for the Transonic Truss Braced Wing that it hopes will eventually lift a new-generation passenger aircraft toward sustainability. NASA has contracted Boeing to build a Sustainable Flight Demonstrator and key to the design is a set of long, thin wings that are braced by large trusses that also work as lifting surfaces. It will be known as the X-66A, and the actual prototype is expected to fly in 2028, but in the meantime the old rear-engined descendent of the DC-9 will test the wing concept. It was ferried from Victorville to Boeing’s Palmdale, California, facility on Aug. 17.
“We at NASA are excited to be working with Boeing on the X-66A Sustainable Flight Demonstrator making critical contributions to accelerate aviation towards its 2050 net-zero greenhouse gas emission goal,” said Ed Waggoner, deputy associate administrator for programs in the NASA Aeronautics Research Mission Directorate. Boeing and NASA are hoping for a 30 percent reduction in fuel burn and emissions with the skinny wings and trusses.