Phase Four Reinvents Electric Propulsion With Maxwell

Maxwell in a transparent small satellite. (Credit: Phase Four)

EL SEGUNDO, Calif., June 27, 2019 (Phase Four PR) — Phase Four today introduced Maxwell, the first turn key plasma propulsion solution for small satellites. Maxwell combines a complete propellant management system and Phase Four’s proprietary RF (radio frequency) plasma thruster into a compact form factor.

Designed with ease of integration and operation in mind, Maxwell expands what’s possible for small satellites and rises to the challenge of next generation spacecraft constellations. It combines simplicity with the powerful performance of complex traditional electric engines. In an industry first, Maxwell eliminates bulky high voltage components and electrodes, simultaneously reducing cost and removing supply chain barriers that have long plagued traditional satellite engines.

“We believe that customers shouldn’t have to choose between thrust and efficiency when it comes to propulsion. Maxwell provides the best of both worlds, delivering simple plug and play delta-V,” said Beau Jarvis, Phase Four CEO. “Maxwell will enable rapid ROI for low Earth orbit small sat constellations looking for 4-6 year operational lifetimes.”


RF thruster in a vacuum chamber. (Credit: Phase Four)

Maxwell is the most powerful electric propulsion system of its size, delivering up to 10 mN of thrust and up to 1,400 s of specific impulse, with total impulse of up to 14,000 Ns. Maxwell is ideal for small satellites (20 to 500 kg) with 300 to 500 W power budgets.


Turn it on and go. Maxwell is an instant startup propulsion unit. No delays. No need to warm and condition cathodes.


Maxwell marks a new digital era for small satellite propulsion. Equipped with a robust, flexible interface, Maxwell can finely tune thrust parameters on orbit to accommodate changing mission needs.


Maxwell diagram (Credit: Phase Four)

With a full 1 kilogram tank of xenon, Maxwell weighs in at just 8.4 kilograms and takes up a modest volume of 7.5 x 7.3 x 5.3 inches.


Maxwell is the most cost-effective propulsion system for small satellites available today, offering the most thrust for your buck. Maxwell further lowers the barriers of entry to space. First deliveries of flight-qualified Maxwell begin in 4Q19, and sign-ups for deliveries in 1Q20 start at US $190,000 per unit. Volume discounts are available.

Maxwell will be formally unveiled at the Small Satellite conference in Logan, Utah. Mark your calendars: 9:30am Mountain time on August 6, 2019 at Utah State University’s Eccles conference center in room 203.

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