Broadcast 3402 Dr. Umair Siddiqui

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Guest:  Dr. Umair Siddiqui;  Topics:  The Phase Four radio frequency plasma thruster, plasma science, Hall thrusters, LEO, comsats, mega satellite constellations and more.

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We welcomed Dr. Umair Siddiqui, CTO of Phase Four, to discuss with us their radio-frequency plasma thruster work, plasma science, LEO comsat smallsat mega satellite constellations and more.  We started our one segment 68 minute discussion by asking our guest to introduce us to electric propulsion, plasma physics, Hall Effect thrusters, the PhaseFour electric propulsion with their introductory Maxwell thruster (, LEO smallsat mega satellite constellations and much more.  The initial introduction soon evolved to a more detailed discussion about plasma physics, thrusters, propulsion characteristics, power, fuel, battery storage and of course, the future for LEO mega constellations.  While technical at times, our guest did a great job with the topic so all of us could understand the PhaseFour work, their Maxwell thruster project plus a look at the future for all of this and the use of LEO.  Our look down the road and into the future came near the end of our discussion.

Marshall called near the end of the first half of our discussion.  First, he asked if the earlier SMART-1 mission was really an ion thruster mission from 2004.  Our guest looked it up and said yes it was and pointed out why Marshall picked up on it and made a good call.  In addition, he wanted to discuss satellite inclination, spacecraft optimization, plus traditional satellite design.  After Marshall's call, we received an email from Bill wanting to know about restarting the Phase Four thruster as compared to traditional satellite propulsion systems/engines.  Listen to the tests described by our guest, or what he said about their thruster not having a cathode and what that meant for enabling a near instant restart. 

Umair was asked about their product in flight.  We learned they were not yet flying but contracted to do so soon.  While he did not mention any specifics about his customers or the launchers that would be used, he did say that Maxwell was designed to be flown to LEO on all available launch platforms.

If we backup for a few minutes, do pay attention to the details and explanation provided by our guest between the starting introduction and Marshall's call.  This is where our guest explained their thruster, Maxwell, made sure we knew about electric propulsion and its variations, performance characterizes and propellants including noble gases, water, Krypton and Xenon.  Umair was asked how Krypton and Xenon were obtained so don't miss what he said in response to this listener question.  

After Marshall's call and the questions from Bill via email, our guest was asked a series of business questions.  For example, he was asked to describe the competitive advantage of Maxwell over other electric propulsion thrusters in the market.  Another listener then asked for the pricing strategy for Maxwell.  Our guest did not go into great detail for proprietary reasons but one can see they plan on being very price competitive in the market.  Umair said that their product would be plug and play.  Another set of questions came up regarding compatibility with other thrusters being used and thruster diversification that might be used by a customer. 

Umair was asked for the five and ten year perspective for both PhaseFour and LEO mega satellite constellation industry.  Don't miss what he said about the projections for LEO mega satellite constellation grown which were estimated to be about ten times what it is today.  This was mentioned several times during our interview.  As part of his answer, Umair outlined the post-Maxwell roadmap for the company.  Don't miss what he said about looking forward in this industry.  Moving and going fast was part of his plan. When asked why, other companies and competition and a fast moving industry with fast moving deployment and operations factored greatly in a decision to move and act fast with their development plans.  As for future thrusters, listen to what he said about a thruster that could generate thrust out of the air in the upper atmosphere. 

As we were closing in on the end of our discussion, a listener wanted to know if there was a terrestrial application for their thruster.  Don't miss what he said in response to this question.  Another listener asked him for the most challenging issues faced by their R& D program.  Don't miss what he said and by way of inference, had to say about working with venture capital support and financing.  Before we ended, our guest was asked about NASA business or support, plus the same for DOD, the USAF, national security departments of the government and other federal agency support or involvement.  In the end, I asked if he was subject to ITAR and if could sell to foreign customers.  He said yes, that they were not so concerned with ITAR but do have regulatory requirements with the Export Administration Regulations (EAR).

Please post your comments/questions on TSS blog for this program.  You can reach our guest through Phase Four ( or through The Space Show.




Phase Four's pioneering new form of electric propulsion called RF plasma propulsion.

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29 Oct 2019 Dr. Umair Siddiqui
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