24 thoughts on “Stoke Space”

  2. Rand, no one today is developing an SSTO RLV or even proposing one as far as I can tell.

    Given this, can we conclude that the SSTO RLV projects of 20 to 30 years ago, like DC-1, Venture Star, Roton, etc. were unrealistic?

    If so, what did their advocates miss?

    If not, why aren’t we seeing SSTO RLV proposals and projects today?

    Finally, are you surprised that SSTO RLVs don’t even seem to be on the table these days?

    1. Certainly VentureStar was a terrible concept (and Lockmart should have never gotten the contract for their non-responsive proposal). We’ll probably never know how DC-Y or Roton would have turned out if fully funded.

      I do think that the difficulties of SSTO were underestimated (and Gary might even agree today), but if they’re not being considered today, it’s because it appears that staging isn’t the cost or operational issue that many previously believed, and SSTOs don’t really fit the current marketplace, due to their crap off-nominal performance, whereas payloads want a wide variety of altitudes and inclinations. If we ever start to see large amounts of activity in ELEO, from the equator, that would be the ideal market for an SSTO, if it’s possible.

      1. Isn’t as simple as SSTO don’t lower the amount of rocket fuel used.
        Isn’t using less rocket fuel. what follows Starship?
        So, using zero stage assisted launch- the “first stage” not using rocket fuel.
        But Musk is cheating, he launching a lot rockets per year. That works for almost anything. He doesn’t even need reusablity. Building them even faster, works, also.
        Of course building satellite a lot faster could as important as making reusable rocket.

  3. The article talks about the second stage they are building. Are they really trying SSTO?
    Also says once the second stage is proved they’ll build stage 1. Where does the SSTO talk come from?

  4. I wonder what the possibility is that they end up only building the second stage and launching it on a Falcon 9? It would seem this would be the cheapest, quickest route to proving their reusable second stage concept.

    1. That is a good idea and they should weigh the opportunity cost of using SpaceX and other launchers vs ever building their own first stage.

      1. The development effort to transform the expendable Falcon 9 first stage was monumental .I say that was from my perspective as FAA/AST Chief Engineer, which allowed me to see what most people never: the licensing process. It was brutal even with George Nield heading up AST. I get the sense that it has gotten worse.

        So, yes, if I were them, I would make some kind of deal with SpaceX. Right out of the box, I could see them using a Falcon 9 first stage as an Uber, to get them to, say, 200,000 feet and 10,000 feet/second. That would give the Falcon a milder flight profile,, and leave it with scads of performance margin on both ascent and descent.

        Having a signed contract in hand with a known first stage operator for that kind of arrangement, they would have to put on scuba gear to avoid drowning in all of the cash that would be thrown their way. Hell, I think even I could raise money with an arrangement like that – and I know how damned difficult it is.

        1. Yeah, didn’t you run KellySpace? How to make a small fortune in space: start with a large fortune…

          But yeah, avoiding government licensing issues altogether makes sense.

          1. “Yeah, didn’t you run KellySpace? ”

            I did, indeed. However, I didn’t start with a large fortune and make a small one. I started it while broke, and wound up the same way. Long story with a sad ending. But man, did I have some fun along the way.

          2. I imagine there were some licensing issues involved with towing a spaceplane behind a 747 and fueling it in the air.

          3. Well, my concept didn’t involve “fueling” in mid-air, just towing the launch vehicle with a full propellant load behind a suitable transport aircraft. Towing a more lightly loaded launch vehicle with a hose instead of a tow line, then transferring sufficient propellant to bring the LV up to “full” while in the air was a concept proposed by Mitchell Burnside Clapp. He and I have had a number of discussions over the years about “tow and flow”, and it really does combine the virtues of tow-launch with Black Horse aerial refueling. It might even make the launch vehicle itself able to make orbit without addition stages.

            But the licensing (FAA) issues with my concept were far fewer than for a pad-launched expendable.

          4. This is what bothers me so much about NASA. That sort of thing is precisely the kind of thing NACA did: trying out the new ideas, finding the edge of the envelope. It’s instead up to private space companies to take all these risks and acquire capital just to test the ideas.

            Landing a first stage on a barge and re-using it is something NASA should have been testing in the 1980s. Towing a spaceplane to cruising altitude and launching from there – hell, they were most of the way there with X15.

            So much time and taxpayer money has been squandered on operations that the primary aerospace research has been neglected.

  5. I think much of the SSTO attraction was it seemed like a simple way to get all the hardware back, minus all the risky business of staging and in-flight engine ignition. Another point was, if you need more payload, build a bigger SSTO. Somewhere along the way, it was noticed the risky business wasn’t nearly as hard as surviving reentry. Stoke is building the upper stage and reentry vehicle on the theory that’s the hard part, compared to building a brute force object to lift it into the stratosphere and throw it down range in the right direction. A really big rubber band on a 200,000 foot tall slingshot, now…

  6. “Stoke is building the upper stage and reentry vehicle on the theory that’s the hard part”

    Which is exactly why Elon built the Starship part first.

  7. The problem with SSTO is getting all that extra mass all the way to orbit and then the even bigger problem of getting it all down in one piece, un-melted. Physics abides.

    1. I saw something way back claiming that the Atlas with its balloon tank was, on paper at least, capable of one-way SSTO. Of course, nobody ever flew it that way.

      1. It couldn’t lift off without the booster engine(s). I’ve read the H-II core could make orbit with no payload. I’ve also seen studies that say Starship with 29 sea level Raptors could be an expendable SSTO with a respectable payload, but what would be the point?

    1. I was running some numbers quite a while back. SSTO from Mars is, of course, much simpler. A CO/O2 rocket looked like it might be Mars SSTO capable.

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