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SpaceX's Falcon Heavy center booster lacked ignition fluid to re-light engines

latimes.com

171–180 of 185 posts

Re: SpaceX's Falcon Heavy center booster lacked ignition fluid to re-light engines

#171

Obviously one of the things you don't want "too much of" is a pyrophoric fluid that you need to dump before you can let people near :-). Have they ever published their safeing procedure? I'm wondering if they recover more volattiles than the old shuttle did after it landed.

It doesn't have as much nasty as Shuttle. The TEA-TEB takes care of itself by combusting when vented, but that's the only hazardous material. Shuttle had hypergolics on board which F9 doesn't use (just kerosene, oxygen, nitrogen, and helium.) The rest of the passivation will mostly be purging the engines, closing valves, and releasing pressure in the various tanks and vessels. LOX venting might take a while as it all…

Man, TEA-TEB is a hypergolic pair

Re: SpaceX's Falcon Heavy center booster lacked ignition fluid to re-light engines

#172
post #159

Earlier quoted context omitted.

Hm, I don't know of a rule that specifies how to use the word "about". To me at least, "about 328 feet" seems okay. It gives you more precision than "about 300 feet" while still letting you know that it's not exactly 328 feet.

328 feet is a unit conversion after already rounding to one significant figure

This discussion reminds me of the time Apple quoted surprisingly precise weights for how much material they recovered through recycling[1]. It turned out the figures were converted from heavily rounded metric numbers.

The best part was that in the websites for some some markets they converted the very precise imperial figure back to metric and claimed something that was close to the original rounded number number but off enough to be extra weird (like 2,999 kg of silver).

[1] https://news.ycombinator.com/item?id=11514106

Re: SpaceX's Falcon Heavy center booster lacked ignition fluid to re-light engines

#173
post #46
post #13

Earlier quoted context omitted.

It apparently ran out of TEA-TEB ignition fluid, not fuel: https://space.stackexchange.com/questions/15403/why-is-tea-t... I can't find any info on how much TEA-TEB is carried on-board, only that it's ground supplied for initial launch with the on-board TEA-TEB being used only for restarts. (I'm not even an amateur rocket scientist: I just googled all this.)

If I'm not mistaken, the SR-71 and A12 had enough TEB for 15 restarts. After doing an aerial refueling, they had to use TEB to get back to afterburner.

Which was like a pint and a half. Pretty powerful stuff.

Re: SpaceX's Falcon Heavy center booster lacked ignition fluid to re-light engines

#174
post #20

Has anyone seen any updates on how their fairing recovery attempt went? They had the ship done and seemingly ready back in December - https://imgur.com/gallery/MQcEE

Isn't the fairing just a simple pair of metal casings. Why bother to recover it?

Musk mentioned that they are about 2 mil each.

Re: SpaceX's Falcon Heavy center booster lacked ignition fluid to re-light engines

#175

Earlier quoted context omitted.

Yeah. I guess in space flight you can't just double the calculated requirement. That would be expensive.

Probably not as expensive as losing the entire booster, though.

Expensive as in, if you apply it to everything, the booster doesn't work.

Re: SpaceX's Falcon Heavy center booster lacked ignition fluid to re-light engines

#176
post #165
post #5

This is why we compare hard problems to rocket science. It's so hard to recover from failure of even the smallest sources.

but the hip programming tips these days are to move fast and break things! a rocket certainly moves fast...

SpaceX have been moving fast and breaking things. It's worked out pretty well for them, even in non-software.

Re: SpaceX's Falcon Heavy center booster lacked ignition fluid to re-light engines

#177
post #163

Earlier quoted context omitted.

The video feed didn't stop working, or if it did, it was only for a brief moment. If you watch this part of the YouTube stream, after it cuts back to the two hosts there is a monitor at the far right center of the video that shows the continuing camera feed of the drone ship landing pad. Only part of the monitor is visible, but after the smoke clears over the next few minutes you can see the empty pad: https://www.yo…

Although I understand why they would have done that for click-bait news outlets, it did really bother me that they were so slow in revealing what happened. What I like about SpaceX is that they're always been very open about their failures, even compiling that great video of their failures. Being able to seeing the full result would have been nice, and I spent a fair bit of time for the following hours refreshing Twi…

They weren't only slow about revealing it, they straight-up lied.

Smoke on deck clears, no core visible, deck empty. Both go "oh." and after a pause, while looking at the empty deck: "we're waiting to hear what happens. [...] we'll let you know as soon as we find out" and "we'll [...] know [...] whether it's standing". All while looking at the empty pad.

They saw it didn't land, they found out immediately and didn't let "us" know. Instead they claimed it might be possible it is standing despite seeing the empty deck.

Re: SpaceX's Falcon Heavy center booster lacked ignition fluid to re-light engines

#178

Earlier quoted context omitted.

Hm, I don't know of a rule that specifies how to use the word "about". To me at least, "about 328 feet" seems okay. It gives you more precision than "about 300 feet" while still letting you know that it's not exactly 328 feet.

The point is that extra precision is unwarranted. We only know that it missed by somewhere between 50 and 149 meters, so it's not appropriate to imply that we know it more precisely.

Ah, didn't notice that. Thanks for clarifying.

Re: SpaceX's Falcon Heavy center booster lacked ignition fluid to re-light engines

#179
post #42

Earlier quoted context omitted.

Going all in on the Culture ship names. I'd be happy if he just made 100(ish) more just to name them after every ship that Iain M. Banks named. They don't need to catch rockets, they can just link up and make a floating utopia.

They don't need to catch rockets, they can just link up and make a floating utopia. Well for that, you'd want to change the hull type from a barge to a spar buoy. Given that, there's no reason why they couldn't do both. http://www.technip.com/sites/default/files/technip/illustrat... (Permanent structures in the ocean need to be spar buoys, or some other architecture that are largely immune to Rogue Waves.)

Got any more cool info on permanent ocean structures. Or large ocean structure engineering in general?

Re: SpaceX's Falcon Heavy center booster lacked ignition fluid to re-light engines

#180

I'm someone who doesn't follow a lot about current aerospace capabilities and technologies. Can someone explain why the work SpaceX is doing is so much more exciting than that of United Launch Alliance or Khrunichev or similar systems?

Perhaps the most important reason people are so excited about SpaceX is they are planning to colonize Mars, and are busy working on the BFR to to make it possible. NASA also wants to go to Mars, but their plans are way smaller and they many years behind SpaceX.
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