This artist’s concept of NASA’s X-57 Maxwell aircraft shows the plane’s specially designed wing and 14 electric motors. NASA Aeronautics researchers will use the Maxwell to demonstrate that electric propulsion can make planes quieter, more efficient and more environmentally friendly. Credits: NASA Langley/Advanced Concepts Lab, AMA, Inc. Click to enlarge.

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.

—Administrator Bolden

As many as five larger transport-scale X-planes also are planned as part of the initiative. Its goals—like the X-57—include demonstrating advanced technologies to reduce fuel use, emissions and noise, and thus accelerate their introduction to the marketplace.

The X-57 number designation was assigned by the US Air Force, which manages the history-making process, following a request from NASA. The first X-plane was the X-1, which in 1947 became the first airplane to fly faster than the speed of sound.

Dozens of X-planes of all shapes, sizes and purposes have since followed—all of them contributing to our stature as the world’s leader in aviation and space technology. Planes like the X-57, and the others to come, will help us maintain that role.

—Jaiwon Shin, associate administrator for NASA’s Aeronautics Research Mission Directorate

NASA researchers working directly with the electric airplane also chose to name the aircraft “Maxwell” to honor James Clerk Maxwell, the 19^th century Scottish physicist who did groundbreaking work in electromagnetism.

SCEPTOR. As part of a four-year flight demonstrator plan, NASA’s Scalable Convergent Electric Propulsion Technology Operations Research (SCEPTOR) project will build the X-57 by modifying a recently procured, Italian-designed Tecnam P2006T twin-engine light aircraft.

An advantage of modifying an existing aircraft is engineers will be able to compare the performance of the proposed experimental airplane with the original configuration, said Sean Clarke, SCEPTOR co-principal investigator at NASA’s Armstrong Flight Research Center in California. The Tecnam, currently under construction, is expected to be at Armstrong in about a year for integration of the wing with the fuselage. Armstrong flew a different Tecnam P2006T in September to gather performance data on the original configuration.

NASA Armstrong pilots flew a Tecnam P2006T aircraft in September 2015 to collect data to compare to the X-57. Click to enlarge.

The original wing and two gas-fueled piston engines will be replaced with a long, skinny wing embedded with 14 electric motors—12 on the leading edge for takeoffs and landings, and one larger motor on each wing tip for use while at cruise altitude.

NASA’s Hybrid Electric Integrated Systems Testbed (HEIST) is an experimental wing initially mounted on a specially modified truck. It is used for a series of research projects intended to integrate complex electric propulsion systems. The testbed functions like a wind tunnel on the ground, accelerating to as much as 73 mph to gather data. Researchers have used the testbed to measure lift, drag, pitching moment and rolling moment that can validate research tools. HEIST’s first experiment was called the Leading Edge Asynchronous Propeller Technology (Leaptech). The experiment began in May 2015 at Armstrong and consisted of 18 electric motors integrated into the carbon composite wing with lithium iron phosphate batteries. Tests showed the distribution of power among the 18 motors creates more than double the lift at lower speeds than traditional systems. Click to enlarge.

NASA’s aeronautical innovators hope to validate the idea that distributing electric power across a number of motors integrated with an aircraft in this way will result in a five-time reduction in the energy required for a private plane to cruise at 175 mph.

Several other benefits would result as well. “Maxwell” will be powered only by batteries, eliminating carbon emissions and demonstrating how demand would shrink for lead-based aviation fuel still in use by general aviation.

Energy efficiency at cruise altitude using X-57 technology could benefit travelers by reducing flight times, fuel usage, as well as reducing overall operational costs for small aircraft by as much as 40%. Typically, to get the best fuel efficiency an airplane has to fly slower than it is able. Electric propulsion essentially eliminates the penalty for cruising at higher speeds.

The X-57’s electric propulsion technology is also expected to significantly decrease aircraft noise, making it less annoying to the public.

The X-57 research started as part of the NASA Aeronautics Research Mission Directorate’s Transformative Aeronautics Program’s Convergent Aeronautics Solutions project, with the flight demonstrations being performed as part of the Flight Demonstration Concepts project in the Integrated Aviation Systems Program.