44 thoughts on “Starship/Super-Heavy”

  1. It’s always been serious, but especially these last eight or nine months since the decisions to go stainless and kick the project up to flank speed were made. A launch mount was obviously on the critical path so it’s certainly none too soon to be pursuing the design and construction of same. If, as a SpaceX higher-up recently said, the goal is to initiate commercial service with SHS two years hence, the new launch mount needs to be completed by roughly this time next year, if not sooner, in order to support the test flight program needed prior to flying customer payloads.

  2. SpaceX tends to wait on construction until they are up against the deadline of need, like the landing pads at LC 40 and Vandy, the ASDS ships, etc.

    So, if they are starting on a SH launchpad now, it tells me they think they will need it soon.

    If their SH schedule is anywhere close to what they are saying, SH/Starship probably will see orbit before SLS does.

    I also, at this juncture, think it’s possible that Starship could do a lunar landing mission before SLS does Artemis 1 (EM-1), the SLS first launch (which is slipping yet again) . And Starship is looking well positioned to do a manned lunar landing within the Artemis 2014 deadline.

    So, what if Elon Musk makes an offer; a lunar landing program, COD?

    Starship’s claimed capabilities (especially the downmass and cost) are what is needed for a real lunar program.

    1. Agreed on nearly all counts. A launch mount for SHS a year from now is pretty much the outside edge of reasonable, given the announced schedule for commercial payloads. By the end of this year would be much better.

      As for SHS vs. SLS, I see no real question that the former will beat the latter off the ground. SHS may well have been delivering boxcar loads of Starlink birds to LEO for all or most of a year before even the earliest potential launch date for Artemis-1, which I take to be mid-2021.

      I’m not entirely confident that even an unmanned mission to the lunar surface can be undertaken before that with SHS. If at least one Starship tanker is in-hand by then, though, it is possible. The lunar-bound Starship freighter would need up to five tanker-loads of propellant. But, if Super Heavy is reliably landing on its launch mount, doing five quick turnarounds of a single tanker could make such a mission possible. I’d be delighted to see that happen. Such a mission – especially if it could occur before Artemis-1’s notional launch – would drive a fat wooden stake right through the heart of SLS-Orion.

      1. Work on the SLS launch tower was finished a long time ago, so they’re far ahead of SpaceX in that regard. However, finishing the tower started a hard clock on the launch date: They have to launch SLS before the launch tower is declared a historic monument and they have to build a different one.

  3. I had no idea that it could take so many tanker loads to fuel up a Starship in orbit. I know a tanker variant of Starship would have a lower dry mass, but, come to think of it, I have no clue what the Starship fuel load is.

    A quick search shows a possibly outdated 240 tons for Starship fuel load (wikipedia). *IF* so (and that’s a mighty big if, I know) a Starship tanker ought to be able (due to having a lower dry mass, thus more prop) fill it up in two missions. Ah, or, not… I just remembered that this would not be done in LEO, but something closer to GTO, so that would cut into the tanker’s prop payload by quite a bit.

    But, no matter what, for Starship to do anything more than high lunar orbit, they’d need the tanker version to fill it up (I suspect they’ll have more than one SH by then, too). However, how hard would a tanker variant be to build, given their construction methods? I’m having a hard time believing what I’m seeing (spaceships being built in open air, like water tanks) but if that method works, it’s revolutionary for construction speed and certain design changes.

    My current SWAG regarding Artemis-1 is, unless they cut a lot of corners (which can end in RUD) mid 2022. (I almost typoed that to 2202, which might actually be more realistic..) I know Starship doing a moon landing before SLS flies is a bit of a stretch, one for which everything has to go near perfect for Starship’s schedule, but it sure would be a wonderful thing. (BTW, I’m thinking unmanned for the first one). I’d like nothing better than seeing a Starship on the moon with SLS yet to make it to orbit, because as you say, that’d drive a stake through the heart of SLS/Orion. Heck, even flying DearMoon before SLS flies would probably do that, and do it well indeed.

    1. I don’t know the exact orbital elements of the Starship pre-TLI refueling orbit, but I recall it being pretty high altitude. The Starship propellant load at liftoff is 1,150 tonnes, much of which it will probably have to burn to get its 100 tonne payload up to that refueling orbit. So needing five tanker trips to provide enough juice for TLI-ing a 100 tonne payload to the Moon, then coming back to Earth sounds entirely reasonable.

      I agree that getting to a place where commercial service with SHS can, indeed, be started by mid-2021, and the ability to do an unmanned lunar freight run not much later, is going to be a tough schedule to keep. We should have a good idea by this year’s end whether that still looks reasonable. I’m optimistic.

      I share your rough estimation of SLS-Orion’s debut mission timeline. NASA already seems to be edging toward an announcement that it will be at least mid-2021. Given the program’s recent year-per-year schedule slippage, I think it has one more increment left. Of course, I also think, if SHS is flying by 2021, even if not yet in commercial service for non-SpaceX clients, even the upcoming Artemis-1 delay to an official date of mid-2021 or later might be enough to get the SLS-Orion program cancelled. Here’s hoping.

      1. I did a bunch of Starship math a few weeks ago in a Selenian Boondock’s thread.

        My first conclusion is that Starship as currently described, and fully fueled in LEO, couldn’t deliver a positive payload mass to the moon due to its low mass ratio and thus barely adequate delta-V for a lunar mission. Then I looked at refueling it in GTO and discovered that it also couldn’t deliver as much fuel to GTO as a Falcon 9 because it arrives in LEO with a mass ratio of about 2, and it takes a MR of 2 for it to get to GTO.

        The problem is that when launched on Super Heavy, Starship itself is still doing too much of the work just getting to orbit. It’s ideally sized for efficient payload delivery to orbit, but suffers from the Shuttle’s problem that by the time it gets to orbit, it’s all payload and bricks and no fuel.

        However, if it launches on three Super Heavies, just like a Falcon Heavy, the situation changes radically, and it becomes possible to delivery ungodly payloads (255 tonnes) to the lunar surface with just three launches.

        So I don’t really know what they’re thinking as to the deep space architecture, but piggyback boosters ALA Falcon Heavy don’t seem unlikely.

        1. As an aside, that was calculated based on Starship’s stated dry mass, LEO payload capability, and a reserve for propulsive landing. It’s not a performance calculation from the launch pad to orbit, so if the stated payload capabilities are way off for some particular technical reason, so are my conclusions.

          1. Math is not my strong suit, so please take what I’m about to say with a huge dose of salt.

            George, my only quibbles with your math is that you seem to be assuming that the tanker variant of Starship will have the same mass ratio as crewed Starship. This is just my opinion (I’ve seen nothing to verify it) but I think that’s most highly unlikely. Crewed starship needs a large pressurized section, consumables, life support, a big solar array and radiator array, etc. etc. A tanker needs none of that, though it does of course need roughly the same raptors, thrust frames, and TPS. As a gross rule of thumb, I’m thinking that the tanker version will be a little shorter, but with stretched tanks, essentially replacing the mass of the crew compartment (essentially the forward half, minus the skin) and payload with prop. I think it should therefor get to GTO at about the same mass as crewed Starship, but delivering the dry mass difference (plus whatever a crewed Starship would have arriving at GTO) as prop.

            Also, regarding prop load on the crewed Starship; the figures I’ve seen (which may well be outdated, so more salt, please..) are 240,000kg prop at launch. So, refueled in GTO, it should have 240 tonnes of prop. If we assume 100 tons of cargo plus 100 tons dry mass, at 380 ISP that would give that Starship a delta/V capacity of 7.884 KPS. From GTO, that’s plenty for a lunar landing and return, and I’m not even making any adjustments to account that the cargo would not be present for takeoff from the moon. (from GEO to the lunar surface is, not counting margins and inefficiencies, about 4 kps, lunar surface to earth return is about 2.4kps)

            I’m personally, as a SWAG, using 100 tons as a crewed Starship dry mass, not the 89 tons SpaceX mentioned, because dry mass estimates so often turn out to be optimistic.


          2. I think I was going with 104 tonnes dry mass because I’m counting the required landing fuel as mass that it has to keep on board through re-entry, which I took as 14,000 tonnes. I had 1,104,545 kg of propellant at launch.

            Now, the interesting kicker is that we naturally assume the payload is on top like a normal rocket, but if they’re going to re-enter pitched up at 90 degrees, they’ll still need the CG to be near the center of pressure. They also list a pretty large payload return capability, and that might mean the payload will need to be near the middle of the rocket, not on one end, unless they do something else quite creative so they don’t have to burn a massive amount of propellant to keep the rocket from pitching either nose first or tail first.

            So at this point, I have no clue what the interior layout really is, how cargo gets loaded and unloaded, or where they’ll put it, but I’m prepared for surprises. 🙂

        2. It was an interesting thread, despite starting off with the “Starship/SuperHeavy is too Big!” meme. Here’s what I think:

          OldSpace defenders are living in the past, while NewSpace defenders are living in the present. But Elon Musk and his band of rocketship designers are living in the future and the know something the rest of us don’t.

          I haven’t forgotten the confident pronouncements (some from ULA executives) that Falcon 9 reuse wouldn’t work because it required “new physics.” Hey, maybe there’s a little sphere of unresublimated thiotimolene in the Falcon 9 propulsion bay?

          1. Speaking of thiotimolene, yesterday evening I wondered if I could route the helium for pressurizing the main tanks through the gas generator, which would drop the combustion temperatures enough to allow the burner to run near stoichiometric or even lean and quit dumping unburned propellant overboard.

            The exhaust gases would be CO2, H2O, and helium, and the CO2 and H2O would easily condense or freeze out by passing the exhaust through a LOX heat exchanger, and the helium could be returned to the tanks, either rewarmed or left cold. Heck, it might be possible to bubble the entire chilled exhaust stream back to the tanks and just let the frozen exhaust products mix in and get pumped through the engine with the rest of the propellants.

            And of course if the gas generator needs more helium than tank pressurization does, the helium could just be recirculated from the top of the tank with small pump.

            I haven’t found any references on doing anything like this, so I figure it was either rejected as unworkable back in the 1950’s or 60’s, or there are some technical complexities or thermodynamics that I haven’t looked at yet, or nobody has ever bothered with it.

            Has anybody heard of anything remotely similar?

      2. I’m always doubtful on SpaceX timelines. “Elon time” became a saying for a reason. 🙂 However, I’m even more a skeptic on SLS timelines, so I am am confident that, should SpaceX have a schedule slip, SLS will surpass it with a larger schedule slip.

        I still remember some of the SLS mafia slamming Falcon Heavy as a “Powerpoint Rocket” because, they assured us, Falcon Heavy doesn’t really exist (no hardware seen, so just vaporware) but SLS does exist (at the time, there was no SLS flight hardware). And, FH did indeed have massive schedule slips, but SLS had more, so here we are; FH is operational and flying missions, SLS is, well, SLS.

        My guess is that in order for Starship to make it obvious to a degree that even congress can’t fight, Starship (cargo version) will need to be flying missions, plus the crewed version will need to at least exist and have flown, and so will the tanker version. I think that once they demonstrate in-space refueling, it’s a done deal, especially if SLS is still yet to get to the pad.

        1. “Elon time” is definitely a thing, but it’s also much exaggerated.

          The currently announced SHS schedule has it entering commercial service in mid-2021. That means the freighter version will have been in orbital testing – probably combined with boxcar-class Starlink deployments – for some time by then, perhaps as much as a year. The tanker version will also be well along by then. The crew version will probably be done last.

          SpaceX may well have to do its own crewed testing without NASA imprimatur, at least initially, owing to that agency’s extreme slowness and caution. So Dear Moon should be flyable by 2023 – or maybe 2024 – but I’m much less certain that the makers of those first fresh lunar bootprints in better than 50 years will be made by people riding on Starship. Maybe yes – I certainly hope so – but maybe not.

          Either way, SHS could contribute hugely to Artemis-1, and follow-on missions, via use of the freighter and tanker versions to preposition hundreds of tonnes of supplies and equipment at the proposed landing/base site before humans arrive via whatever mode of transport.

    1. Wow, that will upset the JSC resistance. I’m not saying Gerstenmaier is one of them, but you don’t need much to get the JSC resistance to start whining about the evils of Trump expecting them to accomplish something after 8 years of Obama increasing budgets without expectation.

    2. Way overdue, but a splendid move nonetheless. It has been a mystery to me for quite awhile as to why that man was still drawing a NASA paycheck.

  4. The irony of SLS vs SH/Starship vis-a-vis the 60’s moon race with the Russians? Or maybe Congress has unintentionally started a moonrace with the SLS (core stage) red menace? If SLS didn’t exist would there not be the pressure to proceed? Or maybe having a Blue Origin vs SpaceX would be enough. But then again perhaps only the US Treasury has the pockets deep enough to provide a challenge to the billionaire privateers. The value of SLS is motivational not operational. Let’s build a rocket that will guarantee space expansion failure as a challenge to private enterprise to get there first with rockets the won’t fail the expansionist goal. This is how SLS may ultimately go down in the history books.

  5. We should test it by putting those people who lick ice cream and spit in bottled tea in supermarkets, and shoot them out into space. If there’s an explosion . . . well, small loss.

  6. Of course it’s serious. Elon Musk is betting SpaceX on Starlink and the Starship/Super Heavy. He is on a wartime footing to get both generating revenue as soon as possible. He is done with updating yesterday’s tech like the Falcon/Dragon, Elon wants the future and he wants it’s now. He knows from his other startups you need to minimize the time between starting the breakthrough and earning revenue if you want to survive. I just hope the government doesn’t throw any speed bumps under him.

  7. It is going to get very hard to defend the SLS when on the launch pad next to it a bigger and more powerful rocket is launching weekly and returning to launch again. Even the densest Congress Critters are going to take notice and start asking questions of the Space Mafia colleagues about what is going on.

    1. Do not underestimate congressional density. There is a reason that an event horizon keeps trying to form around the capitol building.

    2. As I’ve written before, politicians have different measures for success than the rest of us. We foolish civilians are concerned about availability dates, costs, capabilities, and the like. Politicians are concerned about spending in their districts, votes bought, campaign contributions received, and cushy do-nothing jobs created for their family members and cronies. By those measures, SLS is a tremendous (political) success even if it never flies.

    3. Exactly….buggy whips vs Tin Lizzies.

      And the only question is when will the bulk of the buggy whip factories be shut down.

    1. I certainly hope so, but it seems to keep on coming back like the villain in a cheap slasher movie.

  8. I am certainly looking forward to seeing Starhopper make its first hop on Tuesday. Not to mention seeing Starship mk1 make its first 20km test flight in a few months.

    One of the problems with making guesses about what Starship can and can’t do is, SpaceX is always an iteration or two ahead of what we know. It’s what I meant by saying they live in the future.

    1. That was the main problem with my aforementioned look at what Starship’s capabilities might be. It’s hard enough to get solid numbers on Falcon FT block something or other, without some of the various numbers coming from some prior iteration instead of the version in question. And that’s for a vehicle that is frequently flying.

      The technical specs for Starship Enterprise, NCC 1701, are vastly more accurate and sourced than anything published regarding Starship or Superheavy. So I was looking at spreadsheet numbers with dry weights and delta V’s out to six or so significant figures, while in reality the cells should be “not so heavy, heavy, really heavy” and “kinda fast, pretty fast, really fast.”

      It’s a bit like predicting the capabilities of a new Soviet ICBM based on a U-2 photo of a launch tower’s shadow.

  9. When ITS was first announced, I sat down and tried to draw an imagined reusable vehicle that could lift off from Texas, fly to Mars, land, and fly back, all on a single load of fuel. I wound up with a three stage monster that put 990,000 lbs IMLEO, with 54mln lbs liftoff thrust involving 36 F1 class methalox engines. My first thought was to wonder where you’d launch it from. Then I tried to imagine it exploding on the pad. I settled on Jackass Flats in Nevada.

    1. That was pretty funny. It’s not often that a program director on an over-budget, behind-schedule government aerospace project inspires such passions.

      Me: Whew. I guess we can pick up the pace now, eh Pug?”
      Pug: When the Grey Hair is dead, Magua will eat his heart. Before he dies Magua will put his children under the knife so the Grey Hair will see his seed is wiped out forever.
      Me: Alrighty then. Imma go get some coffee.

      Meanwhile, Kieth Cowling has this short little quote

      “[NASA SLS Core Stage Manufacturing Manager Chad] BRYANT: Think of it as a jobs program. So we’re taking – all of the funding that is given us to build this rocket, we’re creating jobs everywhere. And not only that, we’re all coming together to build a product that is going to make us proud to be Americans.”

      That’s almost right up there with AOC’s chief of staff (He of the Indian Hitler fan club) blabbing that the Green New Deal had nothing to do with climate, and was just an excuse to establish totalitarian socialism.

      If it’s really a jobs program, we should limit them to hacksaws and files instead of letting them use power tools.

        1. I’m starting to get (Monty) Python-esque images.
          Or maybe the method of propulsion used in the 100 y/o Exxon Valdez from the movie Waterworld…

  10. I think big rockets should be launched from the ocean and when they explode, the sound just annoys the whales.

    I would launch them from what call, a Pipe launcher.
    Which is huge pipe which is built in a shipyard, and launched
    as a ship is, and is towed to the location.
    The ends of pipe are sealed, and when location one end is unsealed.
    The other end is the platform from which the rocket is launched.
    When unseal the one end, the pipe fills with water and it will float
    vertically. Sort like a sinking ship when bow end rises before going
    under the water. Except pipelauncher designed to hold the air pressure.
    The pipe launcher designed to add and remove air from the pipe and can add air to accelerate a rocket from say 50 to 200 mph.
    A tower and rocket is connected to top of the pipelauncher.
    The rocket fueled, The pipelauncher can slowly lowered to near waterline and can slowly raised say 100 feet above the waterline.
    And launch sequence is lower the top of pipe launcher near waterline and accelerate at some constant rate upward- say at 5 m/s/s or 10 m/s/s. And rocket launches when hundreds of feet above the waterline.
    And pipelauncher is about 600 feet to more 1000 feet tall and 40 or more feet in diameter. So tall and compared it’s length, narrow diameter, but diameter going larger than the rocket diameter- a very big diameter pipe. So accelerates like car or motorcycle does on flat road, but pipelauncher is going vertical, than stops accelerating and then rocket is launched. If one wants a fast speed, then it’s likely the entire pipelauncher will leave the water, after the rocket is launched, but if want to abort the rocket launch, you probably don’t want the entire pipelauncher leaving the water.
    Or you might design pipelauncher to launch at +100 mph, but operationally in beginning limit it to about 50 mph.

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