NASA, which earlier this year announced ambitious plans to resurrect the X-plane program in its quest to research advanced aeronautics, has unveiled the first of those vehicles, the X-57, which will be called Maxwell.
“With the return of piloted X-planes to NASA’s research capabilities—which is a key part of our 10-year-long New Aviation Horizons initiative—the general aviation-sized X-57 will take the first step in opening a new era of aviation,” said NASA Administrator Charles Bolden in a speech prepared for the annual Aviation and Aeronautics Forum and Exposition hosted last month by the American Institute of Aeronautics and Astronautics (AIAA).
In February NASA revealed the return of the X-plane demonstration vehicle program as part of its New Aviation Horizons research, saying, “It’s a shout-out to NASA’s century-old heritage in using experimental aircraft to test advanced technologies and revolutionary designs, and to reduce the time it takes for the tech to be adopted by industry and moved into the marketplace.”
The agency is asking Congress for a 24-percent hike in its aeronautics research budget to fund the projects, which will investigate both subsonic and supersonic technologies. In his speech before the AIAA last month, Bolden further discussed the program. “We expect there will be five mostly large-scale X-planes over the next decade that will flight-test new technologies and systems as well as novel aircraft and engine configurations,” he said. Three of the X-planes will be used to demonstrate possible technologies and configurations to reduce fuel, emissions and noise, Bolden said. The agency is considering technologies such as very high-aspect-ratio wings for boosting efficiency; new composite structures to support non-circular shapes like the hybrid wing body; advanced integration of airframe and propulsion to reduce drag; and boundary layer ingestion concepts to reduce drag, he added. The X-planes will be used to test multiple technologies simultaneously.
Another large-scale X-plane to come later in the program will study hybrid-electric propulsion and aircraft integration concepts. “This is a comparatively new area of research for NASA and for the community as a whole, so we are still investigating fundamental technologies and concepts that will eventually be integrated for demonstration in a large-scale vehicle,” Bolden said, estimating that airplane would fly in the mid-2020s. A fifth X-plane will be used for supersonic research.
Testing Multiple Technologies Simultaneously
Noting that the agency is “eager to move ahead,” NASA plans to fly Maxwell next year, kicking off a four-year flight demonstrator plan. He described the aircraft as “small-scale general aviation sized.”
Maxwell is being developed from a modified Tecnam P2006T twin-engine aircraft. The originally wing and piston engines will be replaced by a high-aspect-ratio wing carrying 14 embedded electric motors. Twelve of the motors will be on the leading edge and used for takeoff and landing, while a larger motor will be placed on each wingtip for use at cruise altitude, NASA said. Maxwell will be powered by batteries, which NASA said will reduce noise and eliminate both carbon emissions and the penalty for cruise at higher speed.
“We’ll be testing new propulsion technology that could result in a five-fold reduction in the energy required for a private airplane to cruise at 175 miles per hour,” he said. “We hope to validate the idea that by distributing electric power across a number of motors integrated with an aircraft in this way we can reach those propulsion goals along with fuel savings,” Bolden said.
The airplane is named after James Clerk Maxwell for his work in electromagnetism and fundamental physics in the 19th century. NASA has dubbed the research involved as the Scalable Convergent Electric Propulsion Operations Research project, Sceptor.
NASA has also begun preliminary design work on the large-scale X-plane to study supersonic technologies, he said, calling that vehicle the Quiet Supersonic Technology demonstrator, or QueSST. “With QueSST we’re trying to design and build an aircraft that flies at supersonic speeds without the annoying sonic boom of current aircraft,” he said. “We plan to provide data to federal and international regulators that could lead to new noise standards accommodating overland commercial supersonic flight.”
NASA began its X-plane program in 1947, the first named X-1. That aircraft became the first to fly faster than the speed of sound. “Dozens of X-planes of all shapes, sizes and purposes followed, all of them contributing to our stature as the world’s leader in aviation and space technology,” said Jaiwon Shin, associate administrator for NASA’s Aeronautics Research Mission Directorate. “Aircraft like the X-57, and the others to come, will help us maintain that role.”