32 thoughts on “The Raptor Crisis”

  1. He has said repeatedly over the years that building a rocket is not as hard as building a rocket assembly line.

    I’m certain he will work out the production issues. This will all make a fascinating book or documentary years from now.

    1. Elon Musk has since commented on it on Twitter, so either he’s hacked (in which case he’d probably be raising alarm bells we’d have heard by now) or it’s real. I think it’s real.

      I further think (pure speculation here) that Raptor 2.0 proved to be a flop; too hard to produce, and too expensive. There might have been reliability issues as well. So, I think this explains his comment from a month or so ago that there would be a new engine, not named Raptor, for Starship.

      My further guess is it’s not a clean-slate resdesign, but it will be a redesign, with a focus on production rate and cost.

      There is a very plausible time constraint; they need Starship to launch Starlink 2.0. sats, (F9 can’t handle stats of that mass and size in sufficient numbers per launch) and my guess is they’ve switched over production from Starlink 1.5 to 2.0, hence the slowdown in launch cadence for Starlink launches. If Starship can’t start launching Starlink in 2022, they’ll find themselves in a bind.

      I think the “bankruptcy” warning was mainly a motivator rather than real, though it’s IMHO fair to say that from a cash flow standpoint, this is quite serious of not corrected, and corrected fast.

      The good news IMHO is Elon Musk didn’t try to sweep this issue under the rug. Rather, he took a bullhorn and broadcast it.

      1. Well, he did cash out some Tesla stock and it wasn’t to make Bernie happy with taxes to be sure. Now we know what he wanted the money for.

  2. Contrast this with BE4 issues. Which management style will produce the best outcome? How many launches will BO or ULA do in a month? What payloads will SpaceX be launching other than Starlink? How many Super Heavies and Starships are expected to be in the fleet? How many of the 2022 launches are expected to survive?

    It doesn’t look like many are expected to survive. Success could relive some of the manufacturing pressure but maybe not next year or ever depending on desired fleet size.

    Musk and SpaceX are incredibly ambitious and hold themselves to a higher standard than their competition. Will they be successful? Eventually, but then we will be reading other articles about other challenges as SpaceX moves from milestone to milestone.

  3. Interesting. Raptor V2 was supposed to stream-line production if I recall correctly from comments Elon make on Tim Dodd’s video taken at Boca Chica and published a few months ago. Apparently there’s been a snag. It’ll be fascinating to learn what it is and if it *does* in fact, affect the design. Design going into production is somewhat inherently a feedback loop.

  4. Starship is the shuttle.
    Starship is planned to improved {unlike Shuttle}
    but what SpaceX has got is Falcon.
    A big error of NASA was getting rid of launcher
    which were competition {“unnecessary competition”}
    to the Shuttle. It seems to me, SpaceX should focus on long term
    use of Falcon. And after Starship is no longer experimental
    then one imagines the end of life of Falcon, but perhaps it still
    is useful, after the Starship is operational.

  5. I’m surprised nobody else has linked this back to the last leaked email from Elon, as this email and crisis seems to explain that email rather well.

    It’s the one that said something to the effect of: “If I give an order, you have three options: do it, tell me why I’m wrong, or tender your resignation. That’s it.”

    I’m guessing that email also coincided with the departure of the two VPs.

    1. I never understood why that leaked statement got such a reaction from the media. It sounds like a policy that many CEO’s would have, and even more might have a 2 choice policy leaving out the “tell me why I’m wrong” option.

  6. Adhesives have been a long standing issue in aerospace for decades, somewhat to my surprise. Witness the shuttle’s tiles falling off. I’m somewhat surprised that the industry as a whole has not devoted more research in this area. One manager on an ISS module I was working on as a CAD designer in the late 90s told me that he hated the amount of time he had to spend dealing with the adhesives’ issue. Adhesion in extreme temperatures, high and low, along with outgassing, IIRC.
    At least they aren’t using garbage products like a certain brand that gets a lot of attention these days, with aggressive marketing and terrible performance in the field. I’ve ranted on this product elsewhere at length, so I won’t do so here..
    One final thought/question: certain US air and naval assets use a lot of tiles to minimize detection. I assume that these use some kind of adhesive. Would it be possible to pass on some of that knowledge to space companies without jeopardizing national security?

  7. Mr. Sindberg, a tiny bit off-topic, but I love the up-skirt view of the engines that head the linked article–the duplicated engines give the thing an almost biological complexity.
    It also piques my desire to understand what I’m seeing. What does all that plumbing do?
    I get the same feeling looking at a lot of ISS photos. Yes, diagrams labeling the various modules abound–but again, all the visible cruft looks like something from a SF spaceship. What does it all DO?
    Do you know of a resource that identifies all these strange vines on our new cathedrals?

    1. In a nutshell, they are to smooth the propellant flow to the combustion chamber so that there are no burps or hiccups in the combustion process. It’s more complicated than that, but that’s the fundamental reason.

      1. Thanks, but I’m looking for more detail than that. The big ducts are propellant feeds, but most of the other stuff, I expect, is for hydraulics, sensing, and so forth. And the ISS complexity is likely to have nothing to do with propellants at all.

        1. The pipes on the outside of the US segment are primarily ammonia lines connecting the heat producing modules with the radiators (the square things sticking off the aft end of the main truss). The piping on the Russian segment is more complex and does involve propellants. Zvezda, Zarya, and Nauka have tanks for hydrazine and dinitrogen tetroxide, as well as water and compressed air. External lines connect those tanks with the active docking ports on the three large modules, plus the ones on Rassvet, Prichal, and Poisk (as well as Pirs, before it was discarded) so they can be replenished by Progress tankers.

          The US segment has no propellants or thrusters, but does maintain primary attitude control for the station via control moment gyros mounted on the Z1 truss, connected to the zenith berthing port on Node 1 “Unity.” The US water lines and air ducts are internal, as are the gas lines associated with the ECLSS units in Node 3 “Tranquility.” Deliveries of oxygen and nitrogen aboard Cygnus are transferred to the external tanks on the Quest airlock via 100-foot pressure hose, similar to what you use on a home compressor, but bigger.

        2. I haven’t spent much time on Raptor plumbing, but some of those pipes have wiring inside them. The rest, methane and oxygen (both liquid and hot gas), and the Starship still uses helium pressurant, though it’ll eventually switch to a hot gas bleed.

  8. Typical. This is the same Musk who got a little slap from SEC for making Tweets about Tesla. And these are the same amateur space journalists (which includes most “professional” space journalists, unfortunatley) now slobbering, wetting themselves, and having orgasms over the impending demise of SpaceX. If this was a publicly traded company, the SEC would be gloating over its new fines, and some lawsuits would be under weigh. But its a private company and Musk can say pretty much what he pleases. He should hunt down and punish the leaker, though, just on principle.

    Some simple facts. All variants of Raptor are cheaper to manufacture than Merlin. So what’s the problem? The 2022 test program, as described, is going to need at least 5 SuperHeavy/Starship combos. Each combo requires 3 RVacs, 10 RSLs, and 20 Rboosts. So that’s 15 Rvacs, 50 RSLs, and 100 Rboosts to comple 5 stacks. Assuming SpaceX will lose somewhere between 2 and all 5 stacks next year (pending a regulatory decision allowing RTLS, due to noise constraints), that means all the engines needed to begin commercial service, including tanker launches for LSS and Starlink launches, will have to be substantial in production during 2022. In this context, the RVacs and RSLs are lost in the noise of producing at least 300 Rboost engines by early 2023. And the Rboost engines take the brunt of the work of getting aloft, running at a high chamber pressure, so they’ll wear out sooner. They *have* to be cheaper, and, apparently, they’re not. Now lets remember what happened to the upper management of Starlink: “Do it, tell me why I’m wrong, or hand in your resignation.” Funnily enough, I watched Battlestar Galactic Razor last night…

    1. And, of course, I can’t count above 10 with my shoes on. 3 Rvacs on Starship, 3 RSLs on Starship, 7 RSLs on SuperHeavy (so 10 RSLs total), and 22 Rboost on SuperHeavy (22 + 7 = 29, right?), eventually rising to 26 + 7 = 33, total engine count 39 per stack, with Musk joking about 42. (Don’t look at me, I only have 20 digits [I think]). The usual exaggerators are claiming SpaceX will lose 10 full stacks before they get one back, so 390 engines lost, or about a year’s production. I’m saying at least two before a landing attempt is permitted (by FAA) and I bet the first landing attempt will be successful. Losing 10 Starships before successful EDL is only a loss of 60 engines, not so bad. It’s also the number of tankers required to fuel the two Lunar Starship flights NASA has bought. The tankers are cheap, less than $10mln apiece, engines and all, so $100mln in tankers for two lunar landings, vs. $9bln worth of SLS launches to launch Artemis II and III with crews.

      1. I can’t count above 10 with my shoes on…

        Using binary, one can count up to 32 on one hand, and 1,024 on two. I use it for counting long rests in orchestra, or counting paces while walking — 1,000 double (2-legged) paces is a Roman mile!

        1. If I could do that I might have amounted to something in this world (SF writer doesn’t count as “something”). On the other hand, since I can’t count paces, I can use my mind for something else useful (like planning for sex, remembering past sex, and writing stories about sex that I can sell for money). I don’t have a one-track mind, it’s just that most of the parallel tracks are variations on a theme (which I’ve tried to explain to various irritated women over the years).

        2. Using binary, one can count up to 32 on one hand
          So….. Are you big thumbian (msf) or little thumbian (lsf)?
          Index finger to modulo or modulo 8?

          Either thumbian way be careful with 4 (or if you do the index modulo 1 a 2). You don’t want to inadvertently signal someone to 2 or 4 or even 64 off….

      2. The current Super Heavies, B4 and B5, have 9 RSLs – one center engine and eight in a ring around the center one with 20 Rboosts in an outer ring on the periphery. 29 engines in all. At some future point, probably quite soon, Super Heavies will get four more RSLs for a total of 33 engines – a central equilateral triangular cluster of three RSLs surrounded by a ring of 10. the 20 peripheral Rboosts won’t change. This new design could debut as soon as B6 or B7 as 13-engine thrust pucks have long since been spotted being delivered to the Starbase production area.

        With 3 RSLs and 3 Rvacs on a Starship, the 33-engine Super Heavy configuration will yield a 39-engine total for the entire stack. Elon has floated the idea that at least some future Starships might be equipped with 6 Rvacs which would raise the total for a complete stack to 42. It would seem that such a configuration would make excellent sense for tanker Starships as the extra engines would allow for higher maximum G and a shorter duration under power during ascent which should translate to a maximized payload capability.

        1. One of my hobby horses being compensating nozzles, I find it odd that there is no consideration of them here.

          1. It’s hard to see how comensating nozzles, per se, would be simpler or cheaper, or even fit under the skirts of SuperHeavy and Starship. That said, it can be argued that the ring of Rboost engines on SperHeavy constitute a species of compensating nozzle, with the RSLs in the center creating the aerospike gas flow plug nozzle. The same thing has been said of N-1, btw. Musk is going for the simplest, cheapest solution in creating Rboost, otherwise he’d just use RSls on SuperHeavy. He’s also noted the the bulk of the impulse for Starship is via the three RVacs, with the 3 RSLs required mainly for steering (when they’ll be throttled down) and landing.

          2. reply to William Barton 8:28 am

            I believe I have figured out at least two methods for getting compensating nozzles in the same envelope size as the standard vacuum engines. Avoiding some of the problems with aerospikes is a good start point. Wrote about a few of them in the selenian boondocks blog.

          3. I went back and looked the esays up. I’d read them before, but it’s been a while. I guess the big problem I have with compensating nozzles (once I got over SASSTO) is they, like tripropellant, mainly seem like an approach to the SSTO problem, and maybe not worth it, given limits to materials and cost. What’s unique about SuperHeavy is the way it straddles the gulf between Big Dumb Booster and Bleeding Edge Performance, and I don’t think anything you get from compensating nozzles improves on that. Maybe if you could build a thermonuclear aerospike? Then again, I’m still a fan of nuclear salt water rockets…

  9. The problems with Raptor production are, no doubt, real, as were the Model 3 production problems at Tesla awhile back. There were executive departures associated with fixing the Model 3’s production issues too. Elon was also inclined, at that time, to wax a tad melodramatic in his e-correspondence. This, too, shall pass.

    1. I will be very curious to see what solution they come up with (or what Musk will call the Rboost replacement). How much Kevlar (or steel) would you neet to contain a full Raptor RUD? A special culvert around the skirt shielding the Rboosts on 3 sides, with Kevlar walls between individual engines, so if one went blammo you might lose its immediate neighbors, but no more? The Rboosts can’t throttle , but you might get away without copensating diametric shutsdowns (a la N-1) by relying on the steering authority of the 7 central RSLs, which can throttle and gimbal. And then you’d be able to simplify the Rboosts by removing the sensors and lines thereof, and most of the electronics. All you really need to know is, is it lit? If it blows up, well then it’s not really lit anymore…

  10. How many times can a Raptor engine be used? How many does Elon plan to make a year? How many is he making now? Like per week, or month? How much does it cost to make a Raptor engine?
    I’m hoping that he can soon get this solved.

    1. The current answer is “no one knows.” For Merlin, the goal was ten reuses minimum (now reached) and a production rate of 400 per year (also reached). Musk has said he can repurpose much of the Merlin assembly line for Raptors when the time comes (obviously, that time was right now). Musk has also said the initial protype engines cost $2mln apiece, that the current cost is under $1mln apiece, and that the asperational goal is for the average Raptor engine to cost around $250k apiece. Rboosts are the main engine type, with RSLs around 25%, and RVacs almost lost in the noise. For Starship to work out financially, the Rboosts probably have to last dozens of launches, with an asperational goal of 100 flights. Merlin is the forerunner for all this, as we see how many flights they survive down the line.

  11. I rarely regret my age,but sometimes… Well. In my life I was a good mechanic, a superior computer programmer, and arguably one of the best writers to come out of the late 20th century. Watching Starship take shape, I sometimes feel wistful. If only this has happened in 1981, when I went to see STS-1 take off, and then, back at the shipyard, some co-workers and I wondered if we could get jobs working on it (marine machinery mechanic and airframe mechanic are convertible trades for blue collars and some of us had done both). Etc.

    1. Horror writer Owl Goingback had been an airframe mechanic when young, and we had a fine time some years back exploring the engineering spaces of the Queen Mary together. It’s fairly easy to imagine the two of us (in younger bodies!) making emergency repairs to a Starship adrift off the moons of Saturn…

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