Comment by dpifke
1 day ago
Preliminary indication is that we had an oxygen/fuel leak in the cavity above the ship engine firewall that was large enough to build pressure in excess of the vent capacity.
Apart from obviously double-checking for leaks, we will add fire suppression to that volume and probably increase vent area. Nothing so far suggests pushing next launch past next month.
Reminds me of one of NASA's reckless ideas, abandoned after Challenger in 1986, to put a liquid hydrogen stage inside the cargo bay of the Shuttle orbiter [0]. That would have likely leaked inside that confined volume, and could plausibly have exploded in a similar way as Starship.
[0] https://en.wikipedia.org/wiki/Shuttle-Centaur
- "The astronauts considered the Shuttle-Centaur missions to be riskiest Space Shuttle missions yet,[85] referring to Centaur as the "Death Star".[86]"
I wonder if it's related to the loose panel flapping about at the left of the screen here: https://youtu.be/qzWMEegqbLs?si=aUlI6zfkH3bZCmVm&t=111
This sounds like one of those "and also" things. I'd say you add fire suppression AND ALSO try more to reduce leaks. It's got to be really difficult to build huge massive tanks that hold oxygen and other gases under pressure (liquid methane too will have some vapor of course). Are leaks inherently going to happen?
This is meant to be a human rated ship of course, how will you reduce this danger? I know this stuff is hard, but you can't just iterate and say starship 57 has had 3 flights without leaks, we got it now. Since I have no expertise here, I can imagine all kinds of unlikely workarounds like holding the gas under lower pressure with humans on board or something to reduce the risk.
This might be one of those components where it just needs to be built without problems, and improved safety means fixing individual design and manufacturing flaws as you find them, until you’ve hopefully got them all.
This can work. Fundamental structural components of airliners just can’t fail without killing everyone, and high reliability is achieved with careful design, manufacturing, testing, and inspection. I’m not sure if a gigantic non-leaky tank is harder to pull off that way, but they might have to regardless.
We’re going to have to accept that space travel is going to be inherently dangerous for the foreseeable future. Starship is in a good position to improve this, because it should fly frequently (more opportunities to discover and fix problems) and the non-manned variant is very similar to the manned variant (you can discover many problems without killing people). But there are inherent limitations. There’s just not as much capacity for redundancy. The engines have to be clustered so fratricide or common failure modes are going to me more likely. Losing all the engines is guaranteed death on Starship, versus a good chance to survive in an airliner.
All other practical considerations aside, I think this alone sinks any possibility of using Starship for Earth-to-Earth travel as has been proposed by SpaceX.
High reliability of airliners is achieved by having redundancy of all critical parts. The idea is no single failure can cause a crash.
For example, if system A has a failure probability of 10%, if A is redundant with another A', the combined failure probability is 1%.
That of course presumes that A and A' are not connected.
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Lindbergh's Spirit of St Louis had the main fuel tank directly in front of him. This was in spite of his primal fear of being burned alive. In some airplanes you sit on the fuel tank.
Given that a) most human rated rockets have had 0 flights before use, and b) I'd expect each starship to have at least 10 flights, and at least 100 in total without mishap before launching, the statistics should be good
I don’t think (a) is true. The Shuttle flew with people on its maiden voyage, but that’s the only one I can think of.
(b) is true and should make it substantially safer than other launch systems. But given how narrow the margins are for something going wrong (zero ability to land safely with all engines dead, for example) it’s still going to be pretty dangerous compared to more mundane forms of travel.
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I'm not sure there's fire suppression effective enough for this type of leak (especially given rocket constraints)
Aerospace fire suppression is generally Halon, which would purge the cavity with inert gas.
Actually the Super Heavy (first stage) already uses heavy CO2 based fire suppression. Hopefully not that necessary in the long term, but should make it possible to get on with the testing in the short term.
What is a long term solution for this? Is there something more than "build tanks that don't leak"? I'm sure spaceX has top design and materials experts, now what ;-).
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That's interesting
However if you see the stream you can see one of the tanks rapidly emptied before loss of signal
It seems this was not survivable regardless of fire or not
It might not even be about fire suppression. Oxygen and different gases can pool oddly in different types of gravity. If oxygen was leaking, it may be as simple as making sure a vacuum de-gases a chamber before going full throttle.
We know nothing, but the test having good data on what went wrong is a great starting point.
Replying to this comment so people can see the incredible video of the breakup taken from a diverting aircraft:
https://www.reddit.com/r/aviation/comments/1i34dki/starship_...
If you can displace the oxidizer/air remaining in the volume why not.
The initial tweet says:
> we had an oxygen/fuel leak
If that's correct, then you can't just remove air. The only option would be to cool things down so it stops burning.
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just increased venting to keep any vapor concentrations of fuel and oxidiser below that capable of igniting, even simple baffling could suffice as the leaks may be trasitory and flowing out of blowoff valves, so possibly a known risk. Space x is also forgoeing much of the full system vibriatory tests, done on traditiinal 1 shot launches, and failure in presurised systems due to unknown resonance is common. Big question is did it just blow up, or did the automated abort, take it out, likely the latter or there would be a hold on the next launch.
There’s no way that was anything but the automated abort — it was a comprehensive instantaneous rapid event. Or I guess I’d say, however it started, the automated abort kicked in and worked.
Would be unpleasant if there was crew. Of course this thing is pretty far from human eating.
Would be unpleasant if there was crew.
19 people have died in the 391 crewed space missions humans have done so far. The risk of dying is very high. Starship is unlikely to change that, although the commoditization of space flight could have reduce the risk simply by making problems easier to spot because there's more flights.
The higher frequency of launches seems likely to have a big impact on reliability. It's no different than deploying once per day vs once per month. The more you do it, the more edge cases you hit and the more reliable you can make it.
SpaceX also has a simplification streak: the Raptor engines being the canonical example. Lower complexity generally means less unexpected failure modes.
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Modern space ships are very likely to change that, as designs mature and improve.
Early aviation was extremely dangerous. Now a plane is among the safest places to be.
I could imagine the risk going down to a few times air travel after 50+ years of operating a mature launch system.
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Test flights.
My tests keep failing until I fix all of my code, then we deploy to production. If code fails in production than that's a problem.
We could say that rockets are not code. A test run of a Spaceship surely cost much more than a test run of any software on my laptop but tests are still tests. They are very likely to fail and there are things to learn from their failures.
Running a code test doesn't require firing a rocket.
How would you test a rocket?
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Thank god you're not building rockets.
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He just means MORE checking for leaks.
They already implemented a whole host of changes to the vehicles after the first test back in 2023. There's a list of corrective actions here.
https://imgur.com/a/Y9dd43o
Even NASA years into their existence has suffered catastrophic fatal failures. Even with the best and most knowledgeable experts working on it we are ultimately still in the infancy of space flight. Just like airlines every incident we try and understand the cause and prevent it from happening again. Lastly what they are doing is incredibly difficult with probably thousands of things that could go wrong. I think they are doing an amazing job and hope one day, even if I miss it, that space flight becomes acceptable to all who wish to go to space.
I you are referring to the two Space Shuttle accidents, both of them could have been avoided with just a little bit more care - not launching in freezing temperatures for Challenger, and making sure insulation foam doesn't fall off the tank for Columbia.
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Can you name a space company with less failures? Also I think it is unfair to even compare SpaceX to anything else, because of the insane amount of starts / tests combined unparalleled creativity.
According to this website their current success rate is 99,18%. That's a good number I guess? Considering other companies did not even land their stages for years.
https://spaceinsider.tech/2024/07/31/ula-vs-spacex/#:~:text=....
Success rate isn’t a great metric for efficient initial work: it will keep improving as more launches are done, regardless of the initial work.
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It says right there in your source that that figure refers to Falcon in particular. For comparison, Starship's current track record is 3/7 launch failures (+1 landing failure).
There's an order of magnitude difference between them. If they were cars, it'd be like comparing the smallest car you can think of vs one of the biggest tanks ever made.
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It's just taxpayer money they're blowing up, so it doesn't really matter.
The taxpayer money is for r&d. We should be very tolerant of failure. Aggressively testing with real hardware is a key part of how we learn to make a more robust systems. Fear of failure and waste will slow down progress.
They're blowing up their own money, unless you still count it as being the taxpayer's after the government pays them for launch services.
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It sounds like he's talking to investors and not to general public.
In my experience in corporate america you communicate efficiency by proclaiming a checklist of things to do - plausible, but not necessarily accurate things - and then let engineers figure it out.
Nobody cares of the original checklist as long as the problem gets resolved. It's weird but it seems very hard to utter statement "I don't have specific answers but we have very capable engineers, I'm sure they will figure it out". It's always better to say (from the top of your head) "To resolve A, we will do X,Y and Z!". Then when A get's resolved, everyone praises the effort. Then when they query what actually was done it's "well we found out in fact what were amiss were I, J K".
He's talking to the FAA, because this will trigger an investigation and would usually mean months of no launches.
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