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Space Businesses

SpaceX Starship SN-1 Fails Pressure Test and Explodes (space.com) 96

SpaceX envisions Starship as a 387-foot-tall (118 meters) spacecraft/booster that can carry up to 100 people to Mars. Pig Hogger (Slashdot reader #10,379) tipped us off to this progress report from Space.com: SpaceX's new Starship prototype appeared to burst during a pressure test late Friday (Feb. 28), rupturing under the glare of flood lights and mist at the company's south Texas facility. The Starship SN1 prototype, which SpaceX moved to a launchpad near its Boca Chica, Texas, assembly site earlier this week, blew apart during a liquid nitrogen pressure test according to a video captured by SPadre.com. A separate video posted by NASASpaceflight.com member BocaChicaGal clearly shows the Starship SN1's midsection buckle during the test, then shoot upward before crashing back to the ground...

SpaceX founder and CEO Elon Musk has hinted that many of these prototypes will be needed to perfect the Starship vehicle... Musk unveiled the first full-size Starship prototype, called the Starship Mk1, in September 2019. That vehicle blew its top during cryogenic testing.

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SpaceX Starship SN-1 Fails Pressure Test and Explodes

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  • by timeOday ( 582209 ) on Saturday February 29, 2020 @09:36PM (#59783216)
    I know they expect some of this but it's slightly surprising/disconcerting that with computer models they still can't avoid it. I say disconcerting because certainly the trip to mars will test certain conditions that cannot be replicated in testing here on earth.
    • I'm sure the trip will come with one incredible waiver to sign.

      • by Tablizer ( 95088 )

        Sends lawyers and politicians to test it.

        • "What do you call 100 lawyers on their way to Mars?"

          "A good start."

          • The pressures they will test here will have to be several times the anticipated loads for a Mars landing. Thats how these things are usually done. Unless the vehicle passes tests well in excess of the forces needed for it's anticipated service envelope, it won't be up to the task.
          • by quenda ( 644621 )

            I used to think Musk was crazy. Why would anyone want to live on Mars, except visiting a scientific base?
            But then I realised - his real plan is to build an equivalent of Golgafrinchan Ark Fleet Ship B.
            Genius!

            • Sunsets, Sunrises, the night sky.

              And I guess if I was there with the right lady, she would love to fall asleep in my hug after we watched the skyes.

          • a waste of a trip?
        • by Tablizer ( 95088 )

          (Send)

      • by hey! ( 33014 )

        Well, look on the bright side. The radiation on a trip to Mars would fry your brain like an egg in a hot cast iron pan, leaving you Alzheimer's like dementia and unrelenting terror of commonplace situations.

        This way, it's over quickly.

    • >I say disconcerting because certainly the trip to mars will test certain conditions that cannot be replicated in testing here on earth.

      Men wanted for hazardous journey. Low wages, bitter cold, long hours of complete darkness. Safe return doubtful. Honour and recognition in event of success.

    • Re: Yikes (Score:4, Interesting)

      by im_thatoneguy ( 819432 ) on Saturday February 29, 2020 @10:14PM (#59783284)

      Computer models say "with a good weld this seam will hold."

      But Elon Musk said they were using the wrong settings for the welder.

      They are building this by hand so you end up with hand crafted errors. Each weld is unique and non repeatable. The real rockets will I'm sure be robotically welded and perfect repeatable.

      • In fact, several professional welders looked at the video and declare it to be bird poop, which I guess means horrible welds.
    • Re:Yikes (Score:5, Interesting)

      by Guspaz ( 556486 ) on Saturday February 29, 2020 @10:15PM (#59783286)

      Before this test, they said that the wrong settings had been used in the welding, so they moved the static fire from SN1 to SN2, so they knew in advance that this one was compromised. Computer models can't account for a human messing up the construction.

    • Re: Yikes (Score:4, Insightful)

      by BytePusher ( 209961 ) on Saturday February 29, 2020 @10:15PM (#59783288) Homepage
      The issue is that they need to test the boundaries of their models. Rockets need to be as light as possible. Manufacturing processes and materials need to be affordable. Pressure in tanks with larger volumes grows proportionately with the volume(cubic), so its a LOT more pressure than their current tanks are designed for. If they werenâ(TM)t blowing things up during testing I would be concerned.
      • by BigBlockMopar ( 191202 ) on Sunday March 01, 2020 @12:07AM (#59783430) Homepage

        The issue is that they need to test the boundaries of their models. Rockets need to be as light as possible. Manufacturing processes and materials need to be affordable. Pressure in tanks with larger volumes grows proportionately with the volume(cubic), so its a LOT more pressure than their current tanks are designed for. If they werenâ(TM)t blowing things up during testing I would be concerned.

        Yup.

        Getting to space is incredibly difficult. There are going to be failures. And yes, humans will continue to die. But Elon is on the right track. He's learning manufacturing and machining from Tesla, and taking those lessons - and Tesla Model 3 motors - to SpaceX. He's bringing SpaceX computers and system engineering like the classic inverted pendulum problem (which is a rocket propulsively landing) and reliability to Tesla Autopilot.

        The guy has his fingers in too many pies? No... He has his fingers in all the right pies to meet his goals.

        Look at my username. I love cars, I love horsepower, I love knowing I can smoke the tires off the thing any time I want. It's not so different from someone who wants the fastest computer in the store.. and then overclocks and water-cools it. I've driven some seriously powerful musclecars over the years - Buick Grand National GNX, Ferrari and Lamborghini "supercars", Dodge Vipers, every engine Chrysler stuffed into a car from 1960 to 1990 including a 426 Hemi A-body. (No, I didn't get to drive a Chrysler Turbine - but I have seen one running, and I can tell you that it sounds like a vacuum cleaner when it's idling.) I've stuffed a Buick 231 (3.8L, the "3800") V6 into a Chevette and really was scared of what I had built. My fingers are calloused from welding burns and soldering burns so much that people think I'm either a pothead or a guitarist. So I'm not your typical "Yo, I had it tuned!" fan of the Fast and the Furious crap.

        I was doubtful at first and then I got behind the wheel of a Tesla Model 3. Uh.... all I can say is holy shit.

        When you get right down to it, an electric car is just a cordless drill on four wheels. That's all it is. The Model 3 is an eerily-silent machine which can outperform almost any vintage American musclecar on the 1/4 mile. And it does it as a 4-door sedan with a huge curb weight (batteries, inefficient body design, weirdness in control arms); in that way, it takes you by surprise the way a Buick Grand National's V6 and heavy body-on-frame does. And it *handles*, the low center of gravity makes it feel stable and the weight distribution is centered right under the passenger compartment so your inner ear feels what the rest of the car is feeling in a way that isn't possible with a 700lb chunk of iron up front. I am sold. The only limitation to Tesla's cars are range (especially in cold climates) and recharge times (especially on long trips). But the Model 3 would probably be a fun (!) upgrade for about 90% of sedan buyers.

        Jay Leno is a *huge* car guy, and I like Jay Leno's Garage on YouTube far more than I ever liked his late night show. Jay Leno is not easily impressed by a powerful car, considering he personally owns and drives some of the most powerful cars ever made.

        This is Jay Leno's reaction to the 2020 Tesla Roadster prototype. [youtube.com]

        Sandy Munro is an expert in automotive manufacturing. You'll see he's a salty no-bullshit guy from Detroit, and he really isn't impressed by Tesla's overall body quality. He loves the Superbottle under the hood of every Model 3 as an amazing example of the integration and ingenuity that conventional car companies simply cannot do because of their organizational structure. He loves the pride that the Tesla engineers took in the idea, showing it off with the Superbottle mascot. As for drivetrain, motor, electronics, batteries, he is clearly very impressed by Tesla cars. The tin can on the outside is mediocre; everything else about the Model S and the Model

        • by AmiMoJo ( 196126 ) on Sunday March 01, 2020 @04:45AM (#59783708) Homepage Journal

          He's bringing SpaceX computers and system engineering like the classic inverted pendulum problem (which is a rocket propulsively landing) and reliability to Tesla Autopilot.

          If he has the same attitude towards space flight as he does towards autopilot then you would be crazy to get on one of his rockets.

          The worst thing about autopilot is that he ignores criticism and doesn't fix the flaws in it. It's got to the point now where the government is going to have to regulate it because Tesla have proven that they can't be trusted to do so themselves.

          • It's got to the point now where the government is going to have to regulate it because Tesla have proven that they can't be trusted to do so themselves.

            I think they jury's still out on that one. But the government was always going to need to step in and regulate this. Firstly in case of accident it's not clear where the liability lies. And secondly without regulation people will not accept it unless it reaches unrealistic levels of safety. Even being 1000x safer than human drivers wouldn't be OK. If anythin

            • [...] But the government was always going to need to step in and regulate this. Firstly in case of accident it's not clear where the liability lies. And secondly without regulation people will not accept it unless it reaches unrealistic levels of safety. Even being 1000x safer than human drivers wouldn't be OK. If anything that would be worse because as it is traffic accidents don't make the news, but if self driving cars had only say 10 accidents per year, all 10 would be newsworthy. Not only that but the accidents may well be ones that an alert, well trained, skilled human driver would not have made, because self driving systems will likely have different accidents.

              Yup.

              The car doesn't need to know or care whether it's a cat or a dog running across the road, only that it should avoid hitting it. Things become more difficult when it's a black cat or a pothole - which is it? Easy enough for a human to decide, hard as hell for a computer.

              Now, is that a plastic bag blowing in the wind, or is that a toddler running across the road? Does your computer make a decision to cause an accident with another car (and its relatively-well protected occupants) to avoid hitting a plasti

              • Tesla AP is already safer than the average human drivers. That is a fact. OTOH, it is NOT ready for all situations. It really needs to remain on the highways, and just off of them. This is why I would like to see Tesla Semi cut a deal with state (and maybe province) DOTs to allow AP trucks to fun from 2100 until 0600 on clear nights. In addition, they have to be basically ware-house to ware-house which must be located close to the highway entrance/exit (lot are within a mile. ). This would be ideal for mor
            • by AmiMoJo ( 196126 )

              I don't think it has to be perfect, just make two changes.

              1. Properly monitor the driver with a camera.

              2. Less frequent, more consistent updates that are properly tested, not alpha tested on customers.

              The systems used by Cadillac, Nissan and Lexus are all much better in these regards.

              • The systems used by Cadillac, Nissan and Lexus are all much better in these regards.

                and more dangerous than Tesla's AP.

                • by AmiMoJo ( 196126 )

                  No, they are a lot safer. They use HD maps to locate the car to within a few centimetres on the road and a camera to make sure that the driver is paying attention, so the driver can go hands free. This has two advantages that Tesla would do well to copy:

                  1. It only works on specific roads, you can't enable it where it isn't safe to do so.

                  2. You can't fool the driver attention monitoring system with a bit of fruit, or any known way.

          • by Teckla ( 630646 )

            If he has the same attitude towards space flight as he does towards autopilot then you would be crazy to get on one of his rockets.

            The only thing Tesla Autopilot is guilty of is a very poorly chosen name for the feature.

            They make it extremely clear it's a driver-assistance system. The driver is still expected to pay attention, and Tesla has even built in some features to help ensure that as much as possible.

            That being said, they really, really should rename it.

            • In that case, they should rename airplane autopilots as well. Do you seriously think airplane pilots are not expected to pay attention? When the autopilot crashes a plane (and they do, occasionally), it's almost invariably classified as pilot error because they should have caught the error and intervened.

              • by Teckla ( 630646 )
                I respectfully disagree. Airline pilots are highly trained (hopefully). We're talking about the naming of a feature for a mass-market audience here, not for highly trained airline pilots.
                • U are missing the point. In both the aviation and EV, the pilot/driver KNOW that the AP is not 100% and that they are supposed to watch. These ppl are elected to not do so.
                • Small airplanes, flown by hobbyists with barely any training, have autopilots too. The earliest autopilots could simply fly an airplane straight ahead. Training has nothing to do with it. it's simply a term widely used for automated systems that assist in controlling an airplane, boat or other vehicle.

                  Straight from Wikipedia:
                  An autopilot is a system used to control the trajectory of an aircraft, marine craft or spacecraft without constant manual control by a human operator being required. Autopilots do not

            • No, it really does not need to be renamed. Look, when looking at the vehicles and when buying it, Tesla makes SURE that customer KNOWS that AP is not fully ready yet. Their goal is to make it 100%, but it is not there (in spit of Elon promising to having by end of each year ).
              Those few ppl who have died while using AP, in each case, it was because they had gotten complacent and trusted a system that they were TOLD was not ready. In each time, it was not the drive simply sitting back, relaxing, but active
          • wrong. The AP is constantly improving. In addition, it is a neural net, so, it is not like you code it directly for the solution. Basically, you have more and more training and deeper nets.
            As an owner of Tesla and we recently traded our 2013 MS for a 2018 MX, which includes AP, I can now say that I am impressed by it. I see over and over that it does a better job than the average driver. And the fact that it does not get tired is amazing.

            If I did not have young kids, I would happily go in a SX rocket.
      • Exactly. There's a *reason* that "rocket scientist" is universal shorthand for: "pretty much the most brilliant person imaginable", after all. Rocketry is HARD. Like... it's really, Really, REALLY hard; at every level of the endeavor from the design, to the assembly, to parts manufacturing, to sourcing the materials (Or even developing new materials entirely.), to the infrastructure so you can actually launch the thing once it it's built. If it wasn't, everybody could do it. And as much as I enjoyed th

        • Actually, early rocketry, by Dr. Goddard and even the Germans, WAS done with COTs parts. Later, they would make parts, but normally, they were still derivatives. After all, it is cheaper and easier to do so.
    • Re: Yikes (Score:4, Insightful)

      by paul_engr ( 6280294 ) on Saturday February 29, 2020 @11:04PM (#59783364)
      Computer models are only as good as the defects you model. It is very easy to simulate a perfect structure with no localized defects that cause failure points, however it is not possible to build such a perfect structure in reality.
      • Secret sauce for a long time are turbopumps. You are pumping rocket fuel at a fantastic rate at takeoff, and that will create a void or negative pressure somewhere else. So you want to pressurize the top as you suck from the center. But now the fuel flowing is not at the same temperature, causing thermal expansion stress on the joins/rings. A difficult problem for anything thicker than say a 44 gal barrel. The diameter of the rocket is?? Now when the rocket shakes like hell at takeoff, of the fuel resonate
        • keep in mind that just recently, SX had to re-do a large number of parachute equations and understanding. Books are being re-written even now.
          I suspect that many more books will be re-written as SX does more and more R*D.
        • I don't want to imagine a 737max at all, thank you.
    • I know they expect some of this but it's slightly surprising/disconcerting that with computer models they still can't avoid it.

      If computer models were infallible there would be no need for physical testing. Unfortunately, computers only model what you tell them to model and if you forget to tell them something important or don't make something exactly how you told the computer you made it bad things can happen.

    • It was probably a test to see what the actual limit was before it would burst. So they deliberatly pushed it well beyond the safe limits of what they think it should be capable of. Same kind of test that NASA did a few weeks ago with their SLS rocket.
    • The problem is getting people to build it exactly as the computer models it :-)

      I would think that welds are quite chaotic in nature. The heat changes the crystal structure of the steel, the welds are not uniform, etc.

      Steel is really complicated stuff. It's a matrix of iron alloy and hard nonmetallic crystals like carbides. The iron alloy can have five different crystal structures, and can transition between them through heating - which welding does. There is also thermal stress from welding, which you can

      • which is also why SX is moving away from simple manual welding to automated welding.
        It is also why Nuke reactors need to be SMRs so that they can be automated welded.
    • This isn't the SLS, they're not going to put people on one of the first few flights. A manned trip to Mars will come after probably at least a hundred unmanned orbital flights. The high unmanned flight rate is what will prove safety -- at least as far as not exploding. All the other dangers of going to Mars, like radiation and muscle loss and lack of medical facilities and surviving once you get there, are another matter.

      • like radiation and muscle loss and lack of medical facilities and surviving once you get there, are another matter.

        Which is exactly why it should be a 1-way trip to mars until we iron out a number of those issues. Going to mars is less dangerous in terms of radiation, then coming back. The reason is that you can use H2O to shield the radiation. As you get further in the trip, you lose H2o, but your radiation does also goes down. Coming back it is the exact opposite.

    • Computer models don't account for craftsmanship defects. All it would take is to have one weld fail and all that pressure goes out of it, causing it to rip the hole bigger and bigger until you get what we see in the video - all the pressure rushing out so fast that it actually causes negative pressure inside the rest of the vessel, which the atmosphere crushes like a giant empty can of Coors Light.

    • Re:Yikes (Score:4, Insightful)

      by tlhIngan ( 30335 ) <slashdot&worf,net> on Sunday March 01, 2020 @06:36AM (#59783782)

      I know they expect some of this but it's slightly surprising/disconcerting that with computer models they still can't avoid it. I say disconcerting because certainly the trip to mars will test certain conditions that cannot be replicated in testing here on earth.

      Here's the thing - if nothing happened, then the test didn't really do anything. All it tells you is that under the conditions you did the test, nothing happened.

      That really doesn't tell you much - it doesn't even tell you if your models are corrrect - if the model says your rocket will explode if the pressure reaches X PSI, and you test it to Y PSI (Y X), you learn nothing - what if there was an error and it explodes at Z PSI (Y Z X).

      So by having it explode, all of a sudden there's a lot of interesting data. Especially if it's something that was overlooked.

      The truth is, you learn more from failure than from success

    • Comment removed based on user account deletion
    • ...they still can't avoid it.

      Fuck, you people don't get it. They're not trying to avoid [destructive] testing; they're trying to determine limits, not take guesses at them by running software simulations.

    • They could save a lot of trouble and expense and just murder the 100 people on the ground.
  • That blowed up good.
  • by Gravis Zero ( 934156 ) on Saturday February 29, 2020 @09:42PM (#59783226)

    Isn't this why you run tests in the first place?

  • It's their money and nobody was injured.
  • Typically you would test to failure for something like this to validate their analysis models. Flight units would get NON-DESTRUCTIVE testing :) Source: am aerospace engineer.
  • by 93 Escort Wagon ( 326346 ) on Saturday February 29, 2020 @10:01PM (#59783264)

    They undergo rapid unscheduled disassembly.

  • by bobstreo ( 1320787 ) on Saturday February 29, 2020 @10:03PM (#59783268)

    Or if they even bother with pressure testing. Since, "It's ok, no problems here"

  • Making an omelette...

    SpaceX learn from their mistakes. The cylinder / hemisphere boundary is constantly the problem. Sure they know this and sure they'll figure it out. I suggested this:

    https://3dwarehouse.sketchup.c... [sketchup.com]

    but it probably won't fly... ;)

    • by dohzer ( 867770 )

      Maybe they could use the opportunity to change the spaceship's shape to one that looks decent.

      • I'm pretty sure that spaceflight is the ultimate example of function over form. Who gives a shit what it looks like, as long as it performs the way it's supposed to, and meets or exceeds all planned specifications?

        The Apollo LM was sure not a spacecraft that "looked decent" but not only did it perform exactly as it was supposed to even with several computer failures along the way during the landing of Apollo 11, but it exceeded design specification when it saved the lives of Apollo 13 doing what it was nev

        • "with several computer failures along the way during the landing of Apollo 11" - this was a human error that left a radar pinging the command module while another radar was measuring the distance to the ground. This caused the lunar module's flight computer to react to a higher processing load than expected due to 2 radars running instead of 1 radar running. The flight computer was working as designed and reported alarms that the "executive" was attempting to process too much information. Sufficient altitud

  • by Anonymous Coward
    Who fed the Zuck beans AGAIN?
  • Explode? (Score:4, Insightful)

    by AlanObject ( 3603453 ) on Sunday March 01, 2020 @12:04AM (#59783424)

    The article says "explode" but when you watch the video it seems the body of the structure actually seems to implode. Crushed like a beer can with the air sucked out of it. Check the slow-mo repeat.

    Could someone explain what the pressure mode being tested actually is?

    • Re:Explode? (Score:4, Interesting)

      by Bruce Perens ( 3872 ) <bruce@perens.com> on Sunday March 01, 2020 @12:32AM (#59783460) Homepage Journal
      Cryogenic nitrogen. The force of it rushing out creates a vacuum.
      • The force of it rushing out creates a vacuum.

        That doesn't quite make sense; are you sure it's not the sudden cooling-effect that accompanies depresserization? FYI, IDNWTV (I did not watch the vid).

        • Interesting reference:

          Blast wind: At the explosion site, a vacuum is created by the rapid outward movement of the blast. This vacuum will almost immediately refill itself with the surrounding atmosphere. This creates a very strong pull on any nearby person or structural surface after the initial push effect of the blast has been delivered. As this void is refilled, it creates a high-intensity wind that causes fragmented objects, glass and debris to be drawn back in toward the source of the explosion.

          Here. [howstuffworks.com]

    • by k6mfw ( 1182893 )
      Maybe most people when they see something go rapid unscheduled disassembly, they simply say it exploded or blowup. Like back in the days of blowing up an old TV (CRT) set but it actually implodes. Way way way back before CRTs had mesh screens to hold them together if glass breaks.
    • When the bottom came off, the contents fell out. With nothing now inside it dropped the internal pressure below atmospheric pressure. Air crushed the tank.
  • The explosion is seen to start in the side of the vehicle [perens.com]. The lower arrow is where it starts.

    A blowout on the remains [twitter.com] may correspond to this.

  • Careless (Score:1, Troll)

    by Jzanu ( 668651 )
    Hardware is not software. Risky testing with combustible materials gets people killed. Not just technicians at the test sites, but even people living in the surrounding neighborhoods and any that is flying over if it explodes slightly later. Think about that one for a while.
    • Tanks were filled with nitrogen, not combustible fuel. Nearby roads were closed [cameroncounty.us], and I'm sure the same goes for the airspace over the site. I trust the thinking at SpaceX a whole lot more than that of the pundits on teh interwebs.
    • You are kind of an idiot. Do you think Elon was out there with a really big red button yelling "YEEEEEEE HAWWWW" as he mashed it as hard as he could, while fanboys just cheered on?

      They knew it would fail. They wanted it to fail, because in failure you get valuable data. So, you plan for it to fail, and fail safely. They did this by using a non-combustible gas (nitrogen) and clearing everybody well beyond expected hazard zones. Roads get shut down, FAA warns aircraft to stay miles away. The county poli

      • by Jzanu ( 668651 )
        Simply the perspective obtained by not being a Musk worshiping idiot. My point is simply that industrial accidents do happen and there is no control that will prevent all harm.
        • But not worshiping Musk still makes you post idiot comments. The SN1 was not going to fly. The tank was full of an non-flammable fluid. Testing was to find limits in the construction. Your post shows you as an idiot regardless of what you think of Musk.
  • by nospam007 ( 722110 ) * on Sunday March 01, 2020 @05:39AM (#59783744)

    Isn't a pressure test exactly that, increasing pressure until it makes boom?

    • Isn't a pressure test exactly that, increasing pressure until it makes boom?

      Yes. They'll learn a lot more from this "fail" than if it hadn't goon boom.

  • This is why they can do things so quickly. Its funny how upset software people get when hardware is experimented with. That type of thinking is exactly why NASA takes forever to do anything. This should be a mantra: Test often and fail early.
  • Test, break, repeat until success.

    Unlike certain aircraft makers, they're not hiding their process.

  • This post was previously hidden by defensive fans, but the reality is this: Hardware is not software. Risky testing with combustible materials gets people killed. Not just technicians at the test sites, but even people living in the surrounding neighborhoods and any that is flying over if it explodes slightly later. Think about that one for a while.
    • Right, please post an URL on how you burn liquid nitrogen by itself.
    • All the pressure-vessel testing protocols that I've seen have you starting the certification programme by filing the vessel with water then jumping the pressure to a few MPa (note volume pumped), 100MPa (note volume), 150MPa (note volume) ... going up in steps until you approach your working pressure, and then in smaller increments to get to your test pressure. As you go on, you plot up (manually, by computer, meh) the pressure versus volume pumped and start to get very careful when the pressure increases

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