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Musk says SpaceX knows what caused the latest rocket failure
- Trisell 10y agoSeems best that they found this out at this stage instead of when they had 3 humans setting on top of it. While the loss of the cargo is regrettable, it in no way is as damaging as the loss of 1-3 lived would have been on SpaceX.
- krastanov 10y agoI agree with the general sentiment, however SpaceX and others have said that this particular explosion would not have harmed any astronauts. The Dragon 2 crew capsule has a launch abort system - if an explosion happens the Dragon launches off to a safe distance using its own thrust.
- arcanus 10y agoIn principle. Best way to keep astronauts alive is not having to use the launch abort system.
- tunap 10y agoWhy do they not use this continency for saving the capsule & non-living cargo, as well? Surely the recommissioning costs would be less than full replacement of equipment+cargo & would give working knowledge for any future "live cargo" aborts.
- deleted 10y ago[deleted]
- Anchor 10y agoThey could, when Dragon 2 is in use for supplying ISS. But Dragons do not carry the kinds of payloads lost in this case. The satellite is on top of the second stage and covered by fairings. There's no craft on top of second stage, so there is no launch escape system.
- Retric 10y agoLaunch abort systems lowers the amount of cargo they can carry and only help in a small fraction of cases. Overall it's not worth it.
- sandworm101 10y agoThere is no point of a launch abort system if the cargo saved would not survive being saved. You cannot just accelerate a satellite to 10g then drop it into the ocean by parachute. Humans in flight suits, strapped to chairs inside watertight capsules, are actually pretty tough in comparison.
- kobeya 10y agoFor non-living cargo it is cheaper to buy insurance.
- dogma1138 10y agoIIRC the stress on the capsule is actually considerably greater during LPAS than during any normal launch (remember that the capsule has to outrun the rocket if anything goes wrong), not to mention a potentially hard landing. So overall unlike humans there is actually pretty low chance for the cargo to survive intact and satellites isn't something you can just fix a dent in, taking it apart doing a full analysis of every component checking for stress, microfractures, and pretty everything else under the sun would probably cost just as much if not more than building a new one. In this case insurance is pretty much the way to go, especially once you consider the added costs of actually building a LPAS or IFAS for satellites / in orbit release payloads and the fact that they have very little chance of surviving the abort without any damage.
- kuschku 10y ago> The Dragon 2 crew capsule has a launch abort system But ITS, the Mars rocket from SpaceX, won’t have a launch abort system. At all.
- hga 10y agoWell, SpaceX does have a launch escape system, as did past US rockets and the current Soviet/Russian one (https://en.wikipedia.org/wiki/Launch_escape_system https://en.wikipedia.org/wiki/Launch_escape_system), it's the Shuttle that was anomalous in having no provisions for crew survival if something happened after the first few test flights. Although look at the bottom of that link, operationally they've been a mixed blessing, saving one Soyuz crew, but another one wasn't safed after a scrubbed launch and killed a bunch of pad workers. This stuff is hard, "rocket science" really does deserve its connotations of difficulty, and is inherently dangerous.
- sandworm101 10y ago> Shuttle that was anomalous in having no provisions for crew survival if something happened Shuttle had launch abort modes. There was a dead zone during SRB burn, but the rest of the assent had planned abort modes for saving the crew. https://en.wikipedia.org/wiki/Space_Shuttle_abort_modes https://en.wikipedia.org/wiki/Space_Shuttle_abort_modes
- ceejayoz 10y agoPlanned, but the bailout method in particular was deemed pretty likely to wind up with a bunch of dead astronauts, as it required unbuckling and making your way to a hatch and jumping out at potentially several times the speed of sound from an out-of-control launch vehicle.
- kobeya 10y agoNot to mention emergency life support requiring active intervention to work. It was like having seat belts that required you to push a button to engage in the event of a crash. Not surprisingly not a single astronaut survived Columbia's depressurization at altitude, because of failure to engage active life support. (A blessing because they had a literal snowballs chance in hell of surviving what followed, but still...)
- sandworm101 10y agoLaunch aborts are not an options for any tumbling vehicle. A launch abort from a spinning/tumbling rocket would see the capsule fired strait into the ground. Any out of control vehicle is pretty much a lost cause. Shuttle's abort modes, including the bailouts, were premised on the craft being under control. Given the forces involves, if it wasn't under control it probably was about to disintegrate. But the same is true of spaceX-style capsule launches. Whether parachutes would correct a tumbling capsule, or rip it in half, is an open question. They both need to initiate abort procedures at least a millisecond before the craft departs into uncontrolled flight. (And aborts can be triggered automatically, or by someone on the ground.)
- Tinyyy 10y agoI understand that SpaceX and Tesla do some pretty revolutionary stuff and we hope to see them succeed. But is it really meaningful for these ‘glass half full’ comments to sit at the top of every single Elon Musk thread?
- Theodores 10y agoThis is a quick investigation into the 'disaster' and that contrasts with how things normally get investigated, i.e. by big government with findings taking years to see the light of day and with big business and other special interests doing what they can to obfuscate truth and shift the blame onto 'the pilot' (as is usually the way in aviation, car crashes, train crashes and anything else that crashes). Well done to SpaceX for getting to this explanation, I am so glad this has not been blamed on a sniper hired by their rivals!!!
- daphreak 10y agoI understand your criticism but the Columbia Accident Investigation Board released a full report with recommendations for changes 6 months after that accident. Not too shabby. Right now we have a press release that is pretty thin on details from SpaceX. Not quite comparable.
- userbinator 10y agoThe solid oxygen that formed could have ignited with the carbon, causing the explosion that destroyed the rocket. This makes me wonder why the liquid oxygen wouldn't have the same effect? Liquid oxygen is itself an extremely reactive oxidiser (search YouTube videos.)
- endymi0n 10y agoCould it be sharp oxygen crystals penetrating the carbon fiber resin layer - just like what happens when freezing living cells?
- phkahler 10y ago>> Could it be sharp oxygen crystals penetrating the carbon fiber resin layer Why would one keep just a layer of hardened resin between all that oxygen and carbon? Seems like an accident waiting to happen.
- ethbro 10y agoI'm guessing the reason you don't do a lot of "Plan B" mitigation in rocketry: weight and added complexity.
- dogma1138 10y agoThe carbon fiber and resin are the shell (AKA a straight jacket) over usually a thin titanium vessel. Carbon fiber alone won't be enough to keep liquid helium at least from precipitating through it, the darn thing can leak through solid glass when it's cold enough. Not sure about liquid oxygen, but still there is no carbon fiber on the inside of the tank, if nothing else than to ensure that no particulate matter ever gets into the fuel system.
- jordanb 10y agoOn the topic of the dangers of LOX, here's a really fun campy Air Force training video from the 60s: https://www.youtube.com/watch?v=rUKcHe0-m_I https://www.youtube.com/watch?v=rUKcHe0-m_I
- Animats 10y agoStrange. Their previous failure (CRS-7 blowing up in flight in 2015.[1]) was supposedly caused by a liquid helium tank support strut in the second stage breaking in flight. The liquid helium tank is inside the liquid oxygen tank, so a failure there overpressurizes the liquid oxygen tank.[1] This second failure again involves a similar liquid helium tank. Not one under flight stress, just sitting there on the pad. Similar failure, though - tank leaks, overpressurizes liquid oxygen tank, second stage explodes. The Saturn V had helium tanks inside the liquid oxygen tanks, but they were compressed gaseous helium, not liquid helium. Has any other rocket design ever put a liquid helium tank inside a liquid oxygen tank? [1] https://www.nasaspaceflight.com/2015/07/spacex-falcon-9-failure-investigation-focuses-update/ https://www.nasaspaceflight.com/2015/07/spacex-falcon-9-fail...
- JshWright 10y agoOther than the fact that they involved the He tanks, there weren't many similarities between the events. With CRS-7, there was acoustic evidence of the strut failing and the COPV smacking into the tank wall. With AMOS-6, the first indication of any event was the catastrophic failure of the COPV. In either case, the location of the He tank isn't terribly relevant... It was going to destroy the rocket either way.
- caconym_ 10y agoSo how are they going to fix it? Will changes to the loading sequence be enough? Otherwise, December seems a bit soon for a return to flight.
- vayeate 10y agoSeems to be caused by the too-cold liquid oxygen interacting with carbon elements. So either change how the tanks are pressurized with helium to prevent the oxygen getting too cold, and/or somehow insulate the carbon from the oxygen better. Neither seem like insurmountable problems.
- edblarney 10y agoI should hope so ...