• SpaceX experiences anomaly during Crew Dragon static fire
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https://twitter.com/EmreKelly/status/1119721013166657536 https://twitter.com/NASASpaceflight/status/1119729877232517122 More information to come. Red smoke = hypergolic fuel = really bad = could have been an RUD Likely the recently returned vehicle from the DM-1 mission. This has the potential to be very bad. Could push them back months.
Aren't hypergolic fumes extremely dangerous? Glad no one was near that place when it went up https://youtu.be/9549pl7zLjM
Well, better that it happens on a test stand than while carrying a crew. Still sucks.
oh ya that's nitrogen tetroxide
By rocketry standards they're merely "very dangerous", there's far nastier things the experimental rocket chemists have fired up. They're still something you want to stay far, far away from, if at all possible. You can handle it safely, as long as you follow the safety procedures to the letter, including the full hazmat suits and self-contained breathing apparatus. Nitric acids, hydrazines, and nitrogen oxides are not something to fuck around with. The amount of smoke seen in that picture makes me suspect the incident involved more than just the fuel in the capsule - Dragon doesn't have all that much of it, all things considered. Maybe the fire started in or spread to the nearby storage tanks? You can't keep those but so far away, since you have to load it into whatever you're firing.
The smoke is nitrogen tetroxide judging from the colour. Could be as simple as a bad shut down with the valve being stuck open after the hydrazine stopped. Need to wait for more info from SpaceX to see how bad it is.
As comments from reputable sources come in (as well as a leak that someone at SpaceX is going to lose their job over) we now know that the anomaly occurred during the countdown sequence at approximately T-9s prior to the ignition of the engines and resulted in an explosive event. While it is important to recognize that it is much better this happens now in testing rather than an actual mission with humans onboard, yesterday was a very sad day for NASA's Commercial Crew Program and spaceflight as a whole. It's safe to assume that Dragon will not be carrying astronauts to the ISS in 2019.
https://twitter.com/Astronut099/status/1119825093742530560
Ahh, this sucks big ass dick. I hope they figure this shit out quickly.
It's interesting that it wasn't even firing at the time. Could be similar to Starliners abort motor issue last year, which resulted in a fuel leak and them having to redesign the valves in the fuel system.
Better to have happened now, rather than on the launch pad with crew onboard. The video is short, but it's pretty clear that a crew would not have survived the event.
Or while at the ISS, since seemingly intended ignition is not required. If this happened while docked I don't think it would do the ISS much good.
An explosion like that while docked to the ISS would be a nightmare exceeding Hollywood's fantasies of near-orbit space drama. If you were lucky you wouldn't have to haul ass to the Soyuz capsule and abandon the station. This is why you always test thoroughly before deployment.
I think if you were lucky you would have time to haul ass to the Soyuz. This is the same capsule that spent a week at the ISS.
Doesn't it feel weird that this happens so regularly during rocket development? We've been developing rockets that are, fundamentally, the same for half a century at this point. We still have them detonate on the pad. All sorts of crazy failures happen. Don't get me wrong, I recognize that the scale of complexity here is absolutely mind boggling, but it feels like computer modeling followed by computer monitoring should be able to detect these eventualities and prevent them from becoming quite as catastrophic. These were not options during early development, but they seem like the most important addition now that we have the basic physics down. Has the underlying physics of the rocket design really changed that much? I dunno, it is probably just sadness from the setback talking.
Scott Manley has some info: https://www.youtube.com/watch?v=Fl3Jcczz5PY&t=1s
SpaceX makes extensive use of sensors and computer simulations but there's always going to be a discrepancy between a computer model and the real world when you are doing this complex. It's hard to detect things that might not be quite up to spec, if some obscure part was corroded by sea water, and detecting a fuel leak might not do you much good when your fuels do this: https://youtu.be/IcjYdEW_HLQ?t=210
Hypergolic fuels combust when they come into contact with pretty much anything (including, sometimes, themselves), so while they make for incredibly reliable ignition sources for abort systems, they are also incredibly dangerous and volatile even when stored 'safely'. As for the incident in question... It really, really sucks. I know it's better for it to happen now than in flight, but it almost feels... Unfair. It's just part of the process, but at the rate commercial crew (for both sides) has been going, Starship is going to be flying crew before they do. It's kind of bittersweet in a way. As someone who has been incredibly passionate and a huge fan of spaceflight since I was young, it's amazing to see the amount of progress made in just the last few years, and to see the renewed interest in spaceflight that it's brought. On the other hand, the HSF situation in the USA (and honestly, even the world at large) has been incredibly frustrating as an onlooker for the past 10 years. Combined with the recent surge of progress, it makes every setback now, even the small and expected ones, feel kind of like a gut punch. That's just my overly emotional take, though. Hopefully they can get things sorted out and back on track. Also, obligatory: ULA's snipers strike again!
I'm worried about special interests in congress using this as an excuse to shut this down, they already tried over Musk smoking weed.
Is this the first time a capsule has returned from orbit and had it's abort system tested again following splash down?
Still a better track record than when NASA was at the same development point. This is why they do tests like this. This is exactly why. It's better here than in space where people can't escape.
Yeah no hypergolic stuff is childs play compared to a NERVA failure. Main reason why NERVA engines never flew.
I wasn't even thinking nuclear, I was thinking stuff like ClF5, HTP, even just the liquid fluorine+liquid hydrogen rockets. Rocket chemists are a mad lot.
heh, that's the first place my mind went. Blame a mixture of too much KSP and too much Fallout. Rocket scientists are crazy, but then again you have people willing to strap themselves to one end of a giant bomb that's only supposed to explode in one direction rather than all of them.
It's an abort test too no? So what could possibly go wrong at t-9? When an actual abort would be initiated within a second or so. I was hoping to see a crew fly the dragon but thats gonna be delayed now, sad.
Further evaluation of the leak seems to indicate that the blast didn't occur at T-9 but the easily audible countdown is a delayed "echo". If you listen really closely with headphones you can make out the actual countdown. Of course we don't know for sure and everything is speculation until SpaceX makes a statement. It's bad no matter what but all we can do now is hope it's not a worst-case scenario design/manufacturing flaw. I've seen the Dragon "nest" at the Hawthorne facility and a bit of the manufacturing process firsthand and watching all that hard work go up in flames breaks my fucking heart. These vehicles are so unimaginably complex. So many hours lost in a single second. Cargo Dragon seems to still in service for the time being, which is good. Should be flying within 2 weeks or so. We'll see what happens for Crew but yeah, not looking too hot right now.
I wouldn't be surprised if Cargo Dragon gets grounded until the fault is identified. Both have Draco engines (which were tested prior to this), and it's likely both share many common components. I expect NASA are going to want to rule out those common components as the source of the issue before letting Cargo Dragon near the ISS.
Scott Manley said something and I agree with him: maybe the splash down damaged one of these motors or any other subsystem, which could've caused the explosion. Also, why use liquid fuel for abort? Isn't it like deadly dangerous compared to solid fuel?
Generally speaking once you turn solid fuel on you're not turning it off. You can stop squirting liquid fuel into the reaction chamber and you're fine as long as fire doesn't get up the valve into the fuel tank.
It's a different set of trade-offs. Hypergolic liquids are actually a bit more reliable to ignite. With pressurized prop tanks, you literally just open two valves, and bam, rocket is on. Solid rocket ignition is still quite reliable, but it's a few extra nines of reliability. Solid rockets are a bit worse when they explode. The actual blast is harsher, and you tend to get little bits of burning debris floating around. This was actually a fatal flaw in the Ares I, which used a solid first stage, if there was ever an abort and the first stage exploded, there was a near-certain chance the capsule parachutes would be destroyed by little bits of burning solid rocket fuel as it descended. Liquid rockets are also more controllable. You can't throttle a solid rocket motor, any change in thrust has to be literally baked in. SpaceX actually wanted to use the abort motors for a smooth propulsive landing if no abort occurred, since landing capsules under parachutes is often compared to a low-speed car crash in terms of violence. But, hypergolics do have disadvantages. A fuel leak is a lot more dangerous, as the ASTP incident shows. Solids are more dense, and can have higher thrust for a given size and weight. Loading becomes a lot more complicated and hazardous. And, they're just more well-studied for abort motors, since we've been using them forever.
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