PASADENA, Calif. — Phase Four, a company developing an advanced electric propulsion system for use on cubesats and larger spacecraft, announced sales of its thrusters to NASA and Astro Digital May 24.

The company, based in El Segundo, California, said that NASA has purchased one of the company’s electric radio frequency (RF) thrusters for testing. That thruster, to be delivered in 2019, will ultimately be used on a spacecraft mission to demonstrate its ability to support future operational small satellite missions.

In a separate agreement, Astro Digital, a Silicon Valley-based company developing Earth imaging smallsats, will buy Phase Four thrusters for use on its Landmapper series of satellites. Astro Digital, which also manufactures satellites for other companies, will offer Phase Four thrusters on those satellites.

In an interview during the Space Tech Expo conference here May 24, Simon Halpern, founder and chief executive of Phase Four, said the agreements are validations of the company’s technology. “That’s a great vote of confidence from NASA to actually deliver something to them,” he said.

Phase Four’s thruster is a plasma propulsion system that makes use of radiofrequency technology, rather than electrodes, to generate the plasma. The thrusters provide high specific impulse without the expense of alternative systems like Hall Effect thrusters. The company released test results in April by the Aerospace Corporation that found that its thrusters has performance comparable to Hall Effect thrusters.

“What we’ve done is develop a simple, elegant system that has the same performance as the state-of-the-art Hall thrusters, but without all the pain points of those systems,” he said, such as high voltage electronics and cathodes that often cause failures of those systems. “You end up with a simple, scalable, manufacturable, affordable smallsat propulsion system.”

The first flight of a Phase Four thruster will take place later this year, Halpern said, as a technology demonstration mission in cooperation with Astro Digital. “It’s purely a demo of our ability to build proper flight hardware,” he said, including the entire propulsion subsystem of which the thruster is one part.

The Phase Four technology can also be scaled up and used in an array for use on larger spacecraft, including large geostationary communications satellites, he said. However, he said he expected the bulk of the demand to come from large constellations of smallsats and cubesats versus larger satellites.

Phase Four is one of a number of companies offering innovative technologies to serve the growing demand for smallsat propulsion system. Like participants during an earlier panel at the conference, Halpern expected there to be some consolidation in the years to come.

“You have a huge spectrum of options,” he said. “A few people will come out with really great systems proven in the right circumstances.”