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SpaceX Moves Past Explosion With New Launch Plans (cnn.com)
SpaceX plans to resume launching rockets as soon as next week, after completing an investigation into a spectacular launch pad explosion that destroyed a rocket and a satellite in September. From a report on CNN: The news comes following an in-depth investigation into the explosion of a rocket from SpaceX's September mission. The company said in a statement Monday the botched launch was due to a failed pressure vessel in a liquid oxygen tank. The vessel buckled, causing liquid oxygen to accumulate. It believes this led to friction, sparks and the explosion. SpaceX conducted the investigation along with officials from NASA, the Federal Aviation Authority, the U.S. Air Force and the National Transportation Safety Board. The Federal Aviation Administration will have to sign off on the report and issue SpaceX a license to launch. SpaceX appears optimistic it will be launching rockets again soon.
Ten minutes after Challenger blew up, the other engineers I worked with and I were saying to each other: "Watch, it'll come down to some idiot middle manager screaming "Whaddya MEAN I can't ship on time???". The thing about Rocket Science is: IT'S FUCKING ROCKET SCIENCE!!! Shut the fuck up about your pulled-out-of-your-ass ship date!
Because nobody at ULA makes any money, and they certainly don't have taxpayer paid launches.
Might want to take a look at the dollar per payload on competing heavy lift platforms.
I'm a good cook. I'm a fantastic eater. - Steven Brust
You can have $70M of your taxpayer dollars used on his rockets, or you can have $160M of your taxpayer dollars go to Lockheed Martin and Boeing. Your choice.
So:
* Cheaper by 55%
* Built entirely in America
* Doesn't give money to a country we're sanctioning
* No design elements from the 1970s
* Company is doing innovative things to drive down costs even more in the future
* Slightly more likely to explode
Seems like a good thing to me.
LOX is unstable in contact with most organics. To the point that with the exception of some fluoropolymers, it's generally considered that all organics have a critical pressure in which they'll spontaneously combust with LOX. For many organics that pressure is below atmospheric pressure (aka hypergolic). For most plastics it is above atmospheric pressure, but not tremendously so. This includes the epoxy binders used in composites.
Yes, CF is the standard abbreviation for carbon fibre.
The LOX is supposed to be squeezed out of the CF as the COPVs pressurize. The COPV are comprised of a non-permeable aluminum inner liner and a permeable carbon fiber overwrap that bears the load. By freezing solid, the LOX was unable to escape the overwrap as the pressure increased as the COPVs were filled, and was correspondingly pressurized inside of it.
The system was not "designed so that it has areas which are likely to detonate". The LOX was supposed to be squeezed out of the overwrap, not become trapped in it as SOX.
None of their statements that I've come across mentioned "heating". They did, however, mention that the solidification of the LOX led to a pressure buildup. I've read quite a few LOX handing guidebooks (for working on a project involving LOX), and LOX pressurized against carbon fiber is considered an explosion hazard. You don't even store LOX in composite containers in low pressure conditions long-term. You know the main differences between a LOX dewar and a LN2 dewar? The latter often has either no lid and/or contains plastic or composite or silicone components. The former always has a lid and does not contain (non-fluorinated) plastic or composite components, and rarely silicone (fluoropolymers are usually okay). Also some metals don't work with LOX either.
It's not a case of "you say detonation, I say combustion". The spontaneous pressure-induced reaction of LOX and CF is a detonation. The rocket as a whole however was primarily consumed by a deflagration (non-supersonic combustion) between LOX and RP-1.
Nowehere in anything that I've seen from them were "sparks" mentioned.
Your "sparks" and "temperature" comments are directly in contradiction to SpaceX's comments about the conditions causing the formation of SOX and preventing the egress of LOX from the overwrap.
For the love of Crom, am I the only one here who wants to keep the U.S. technologically competitive?
You can do rocketry as ULA does; exactly like we've been doing for the past twenty+ years and have it cost exactly the same as it has for the past twenty+ years.
_Or_ you can invent new, _substantially_ more cost-effective ways of doing rocketry. Whenever you're doing something new in a high-energy field, there's a chance of explosive failure. (Remember Apollo 1?) Hell, explosive failure happens even when you're doing the same old thing. (Remember Challenger? Columbia?)
The only con SpaceX is revealing is the long-play ULA and others like them have been running on the American People. Rocketry can be cheaper, better, and require only domestically-sourced components. All that was required to make this happen was someone who gave enough of a shit to make it happen. This could have happened _decades_ ago, but didn't because the Big Aerospace Contractors were more interested in milking the government teat than providing the best value to the American People.
As a side note, I'm really uncomfortable with their plan to make IPS entirely out of carbon fibre. As they're finding out (and has others have found out in the past), it's really difficult to use LOX with composites.
Well for one thing the pressure in a COPV is several orders of magnitude higher than in a LOX tank so it seems foolish to over react to a failure of composites under extreme pressure and exotic conditioned when future applications will be different in nearly every way. Secondly, you could always work exactly the same as a COPV and line the interior of the composite structure with a thin layer of aluminum to prevent any contact at all. In fact we don't even know if that's not already the plan. In this instance SpaceX simply didn't think it was necessary to prevent contact of LOX and carbon and they were arguably right until they pushed the conditions slightly too far, it's telling that they are returning to flight with the exact same hardware.
You can't radically upset the economics of space flight by doing the exact same things the exact same way everybody else has always done it. You'll end up with the same thing at the same price.