Changing the Way We Move in Space

Changing the Way We Move in Space


Phase Four is a disruptive provider of next generation electric propulsion (EP) solutions for satellites. Phase Four’s RF Thruster represents a revolutionary new architecture that realizes lower cost, mass-manufacturability, miniaturized power electronics, and propellant agnosticism over incumbent technologies, without compromising performance. In 2021 Phase Four’s Maxwell turn-key propulsion system achieved flight heritage and is now being regularly utilized by satellite operators.

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Maxwell is a high performance turn-key plasma propulsion system that leverages miniaturized RF electronics and our electrodeless thruster in a compact form factor.


Maxwell Systems Delivered


Maxwell Systems launched into low Earth orbit


Phase Four is moving into a new facility located at: 12605 S Van Ness Ave, Hawthorne CA

We've Moved


Read more about us and updates in the news.

Phase Four Wins AFWERX Funding Boost for Propulsion Tech Development
Propulsion company Phase Four received a funding increase from the Air Force Research Laboratory and its innovation arm AFWERX.
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The plasma glow created by Phase Four’s novel RF spacecraft engine firing on AFRL’s “green” propellant.
Phase Four’s spacecraft engine first to demo AFRL’s game-changing ‘green’ fuel
Former NASA administrator Jim Bridenstine told Breaking Defense that Phase Four has the potential to "disrupt the in-space propulsion market," and its technology "is important for the country."
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Phase Four Unveils Game Changing Engine for LEO Constellations
Leveraging its new Block 2 architecture, Phase Four announces Max-V, a revolutionary plasma propulsion system available in 2023
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