Broadcast 3658 Dr. John Hunter

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Guest:  Dr. John Hunter;  Topics:  Green Launch, gas guns, shots to space and LEO, the Yuma Proving Grounds, propellant, CO2 in the atmosphere, market analysis and more.

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We welcomed back to the show Dr. John Hunter to discuss his new company, Green Launch.  Find out more about the company, see videos and Green Launch shot examples at  We began our discussion by asking Dr. Hunter to describe Green Launch and introduce us to the concept.  John started by describing their 54 foot tube they use for the gun, plus he told us how they acquired it out of a salvage pile.  John talked about the gun, why it is a green launch, how it recycles the propellant which is largely hydrogen and helium, and does not omit CO2 into the atmosphere as does a typical rocket launch  John had much to say about CO2 in the atmosphere but as you will hear throughout our discussion, the green approach and the recycling of propellant is a big thing for Green Launch.

John talked about his demo and test plan with various test shots coming up, the goal to raise additional funds so they can reach space (the Von Karman line) with their gun and eventually to LEO.  He said multiple times he wanted Green Launch to the Fed Ex for space.  He compared others in the field with the post office and UPS.  John then talked about payloads ranging from 5 to 10 kilos to LEO.  He talked about locations that would be superb for the gas gun launch plus he had separate comments about vertical and horizontal launches.  His current HQ at the Yuma Proving Grounds (YPG) is where they are currently doing their R&D and shot testing.  Based on one of my early questions, he described the Yuma Proving Grounds base to us. 

Listeners started sending us email questions. Bob in Phoenix wanted to know more about the Green Launch timeline.  John talked about their goals, their upcoming 23 test shots and the need for some additional fundraising to get to space.  Another listener, Jerry in Denver, wanted to know about competition and would he be going one on one with the new small launch companies coming into play such as RocketLab.  John said he welcomed all competition but spoke extensively about SpinLaunch.  SpinLaunch came up multiple times during the discussion as John had much praise for their ideas.  John also made it clear that what they were doing had his attention.  John then talked about the Brilliant Pebbles project, nuclear propulsion and then he mentioned Dr. Edward Teller.  John said he knew and had worked with Dr. Teller and referenced his having a meeting with him to find out what Dr. Teller really thought about the 9/11 attacks.  I asked John to tell us that story which he did.  It was an interesting digression from our Green Launch company focus. 

We took a call from Eric who asked multiple questions.  One question was about G hardened payloads but I extended it to ask how one goes about making a payload G hardened.  John had much to say about this and the process.  He told stories about it and he told how&  why Walmart epoxy was a good agent for small parts needing hardening.  Don't miss this question and answer.  Another question asked by Eric dealt with escape velocity regarding the Moon and Mars.  John explained how Green Launch would be welcome on both the Moon and Mars and then he again explained why recycling propulsion was a big deal.  Finally, Eric asked about RocketLab. Don't miss John's reply.  Before ending his call he talked about Green Launch 4 and 5 mega jewel shots, their altitude and energy. 

Email listener Sherry from Dallas asked if it was hard to talk to investors given the Green Launch concept and just how unique it was compared to other launch industry investment opportunities.  Be sure to hear what John said regarding investors and Green Launch.  Roger wanted to know about point to point services with Green Launch.  John said yes, a possibility but he repeated they were focused on cargo, not people.  He talked about the additional work Green Launch was doing with hypersonic testing and suggested this would likely be an additional cash flow source down the road.  SpinLaunch was discussed again as were suborbital launches in general with a focus on Virgin Galactic.

At this point in the discussion, John went back to some of his early gas gun research days when working in Livermore, CA around 1985-86. He said he was not really a space guy but was doing space because he saw it as being essential.  Somehow John and I got off on dogs.  John makes dog toys and talked about some of his toys, plus later when we returned to talking about dogs, he told us a story of how his dog saved his life.  Back to Green Launch, he compared Green Launch to a conventional rocket dumping multiple tons of CO2 in the atmosphere.  This prompted me to ask him what the environmental movement thought of Green Launch.  Listen to what he said.  The bottom line to his response came when he said Green Launch was not yet that visible.  John then mentioned cubesats, SWARM, and transponders.  Carl asked him about ITAR and Helen wanted to know how a 54 foot gun would be lifted to the Moon or Mars.  John explained that Green Launch for the Moon or Mars would be different from what it appears as here on Earth.  Listen for the description. 

John had concluding comments plus a short summary.  Please post your comments/questions for him on the blog for this show.  You can reach him through me or his Green Launch website.




Dr. Hunter's new venture, the Green Launch Company

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16 Mar 2021 Dr. John Hunter
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