Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

SpaceX – Launch Vehicle Failure

news.ycombinator.com

Post reply on HN
Print view View original

321–330 of 347 posts

Re: SpaceX – Launch Vehicle Failure

#321

Post by robzyb »

HeyLaughingBoy wrote: post #320
robzyb wrote: post #319

Earlier quoted context omitted.

> You're supposed to do the fault tree analysis before you build the rocket Elon. How can you do a fault tree analysis before things go wrong? Maybe fault tree analysis means something different to you. According to Wikipedia, it is "a top down, deductive failure analysis in which an undesired state of a system is analyzed using Boolean logic to combine a series of lower-level events." There needs to be an undesirabl…

I'm no Risk expert, but going from memory, you hypothesize potential failures based on experience and knowledge of the module. Then you use the FTA to understand what faults may result in the failures under examination. FTA can be used either pre- or post- event.

> FTA can be used either pre- or post- event.

Fair point.

OP's objection to a post-event FTA still makes no sense, though.

Re: SpaceX – Launch Vehicle Failure

#322

Post by ctdonath »

Edmeral wrote: post #297
dcposch wrote: post #290

I watched the launch live this morning. It reminded me of one of the best interviews ever. Elon Musk after SpaceX's first three launches all exploded: http://archive.wired.com/science/space/news/2008/08/musk_qa I read that in high school, and it's part of the reason I became an engineer. "Far better is it to dare mighty things, to win glorious triumphs, even though checkered by failure... than to rank with those poor…

"Optimism, pessimism, fuck that; we're going to make it happen. As God is my bloody witness, I'm hell-bent on making it work." I got goose bumps reading Elon's response at the end of the article.

The thing I like most about the startup I work for: if anything goes wrong, everyone just objectively addresses what happened, where we are now, and what to do to move forward - an obsessive focus on the next step to success.

Re: SpaceX – Launch Vehicle Failure

#323

Post by will_hughes »

myth_buster wrote: post #240
51Cards wrote: post #235

Earlier quoted context omitted.

Yeah, it is too bad there wasn't some way to deploy the parachute system manually. It would be nice if the cargo could be saved.

I think Gerstenmaier was saying that may be a distant possibility.

While they might be able to recover the items, re-qualifying something that's been dunked in seawater after being dropped from 35km+ is probably a non-trivial task.

That's assuming it wasn't exposed to explosion debris.

Re: SpaceX – Launch Vehicle Failure

#324

Post by Dylan16807 »

hackuser wrote: post #286
engi_nerd wrote: post #271

Earlier quoted context omitted.

SpaceX still looks better than its direct competition, Orbital ATK: Antares CRS-3 turbopump failure, vehicle FTS was activated and launch vehicle impacted very close to the launch pad. $200 million vehicle lost, approximately $30 million in damage to launch facility. Loss of the $424 million Glory satellite due to payload fairing separation failure. *Loss of the $273 million Orbiting Carbon Observatory satellite due…

> I don't think the comparison between ULA and SpaceX is necessarily a fair one. ULA is the beneficiary of inheriting solid engineering teams and practices from very mature programs run by large defense corporations. SpaceX is comparatively very young ... Another commenter said something similar. If I am awarding merit badges, then I agree it's unfair. Otherwise, if I'm looking for someone to launch my satellite, the…

You're focusing on launching a satellite today. Those commenters are looking at satellite launches across the next decade, as ULA reliability doesn't change and SpaceX reliability grows (in theory).

Re: SpaceX – Launch Vehicle Failure

#325

Post by chillingeffect »

Havoc wrote: post #292
51Cards wrote: post #179

From Elon just now via Twitter: "There was an overpressure event in the upper stage liquid oxygen tank. Data suggests counterintuitive cause. That's all we can say with confidence right now. Will have more to say following a thorough fault tree analysis."

>Data suggests counterintuitive cause. What does this sentence mean?

I'm guessing if there was an overpressure event, that one would normally think that it was due to unanticipated heat, or a valve opening incorrectly (too early/late, far/little), etc. but that data from a measurement system on e.g. thermal or flow indicate the opposite, such as temperature doing down instead of up.

I wonder what the specs are for the systems they're using for telemetry... must be a gazillion channels at a high rate...

Re: SpaceX – Launch Vehicle Failure

#326

Post by will_hughes »

greglindahl wrote: post #288
27182818284 wrote: post #272

Earlier quoted context omitted.

And if I recall, some of the SpaceX launches are pricier (though not that level) for the more sensitive payloads--as in there is a Secret-Spy-Satellite optional charge package.

The extra charge is due to the paperwork requirement for these launches... which were imposed after a series of launch failures by LM and Boeing rockets carrying very expensive US Government satellites.

And the paperwork is (in part) because the US Government doesn't purchase insurance on their launches.

Re: SpaceX – Launch Vehicle Failure

#327

Post by lutorm »

Osmium wrote: post #139
MichaelMoser123 wrote: post #115

Good that nobody was hurt. that reminds me that Elon Musk said that Antares rockets are junk, so now his own spacecrafts are exploding. Space tech has its problems. Maybe that will teach him to be a bit more humble. http://www.dailygalaxy.com/my_weblog/2014/10/iss-bound-gear-...

I think that article might be a bit disingenuous. Elon Musk didn't say that in response to the Antares explosion, he said it several years earlier , and the part that's quoted is pretty accurate to be fair. When a failure does happen, nobody goes around celebrating it, whether they're competitors or not, and honestly I believe that includes Elon Musk. I believe that on a human level, but even on a business level it's…

He did express sympathy for Orbital's failure: https://twitter.com/elonmusk/status/527247155954610176

Re: SpaceX – Launch Vehicle Failure

#328

Post by FrankenPC »

pbreit wrote: post #223
FrankenPC wrote: post #221

My only question is, is the real time telemetry at a high enough resolution that the exact cause of the explosion can be ferreted out? I'm guessing yes. This is another very important learning experience. One of countless thousands on the way to reliable space launch and recovery. My only pessimistic thought in all this is that companies like Space X simply do not have the funds necessary to keep absorbing catastroph…

SpaceX at this point is pretty well-funded, still in a solid position to tap capital markets and has a healthy manifest of paying customer launches. There's probably some insurance in place to mitigate financial losses. And this is the benefit of bringing costs down, especially with the complete complete re-use SpaceX is targeting.

Reminds me of that article about the Sony Aibo dogs ending their mechanical end of life. After 16 years, they are failing and they're no replacement parts.

Point being, if Sony had kept going with that incredibly sophisticated robotics tech (for the time) they would be an industry leader right now at a time when robotics is about to explode. Did Sony run out of funds? No. They abandoned the project because of fear for stockholder repercussions. That's what I meant by that comment. Sometimes stockholder flash back is enough to abandon a really great idea.

Re: SpaceX – Launch Vehicle Failure

#329

Post by Dylan16807 »

mikeash wrote: post #114
jacquesm wrote: post #99

Earlier quoted context omitted.

Ah, I see. The English Language never ceases to surprise :)

Yeah, that one is not very obvious. Think of it like a warning: "Don't quote me on this, because if you do, you might find yourself repeating incorrect information." A literal command of "don't quote me because I'm telling you something I shouldn't" would be something like, "Off the record, this is what happened." And yeah, that would be silly to say on the internet.

I would say that the literal aspect is the same no matter how you interpret it. It's just that jacquesm guessed the wrong reason for not quoting. It's still a command.

Re: SpaceX – Launch Vehicle Failure

#330

Post by Dylan16807 »

DavidSJ wrote: post #129
n_coats wrote: post #49

Earlier quoted context omitted.

I saw two big puffs of smoke and initially thought it was the boosters releasing.

There are no solid rocket boosters on Falcon 9.

Falcon Heavy will have boosters, perhaps that's the confusion, unless 'booster' meant 'first stage'.

Nobody said solid.

Post reply on HN