NASA has offered a preliminary version of its first fully electric experimental aircraft, the X-57 Maxwell, at an aerospace laboratory in the California desert.
The aircraft, based on the Italian twin-engine Technum B 2006 T, is being developed since 2015 and is still at least a year away from its first test flight.
The aircraft relies on 14 electric engines powered by lithium-ion batteries.
Although private companies have been developing electric planes for years, NASA's X-57 project aims to design and demonstrate technology that meets standards that businesses can apply for government approval.
Brent Cablah, an official at the department's Armstrong Aviation Research Center, said standards include aviation efficiency, safety, energy and noise reduction.
"We are focusing on things that can support the entire sector, not just one company. Our goal now is to fly this aircraft by the end of 2020," he told Reuters in an interview.