The good news is it seems like a fairly easy thing to fix going forward. Not really an engineering problem as such, but rather a miscalculation
SpaceX's Falcon Heavy center booster lacked ignition fluid to re-light engines
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Re: SpaceX's Falcon Heavy center booster lacked ignition fluid to re-light engines
#72> Those two boosters, which were used in previous launches of SpaceX's workhorse Falcon 9 rocket, will not be reused again, Musk said in a post-launch news conference last week. Why did SpaceX spend resources to get them to safe landing then? I presume, they rather maintain their routine and maintain the success of landing the booster. It would probably be expensive to change their standard procedure. Does any know h…
To analyze/test the used boosters, or to put them on display, probably
Probably both, particularly with the main booster now lost.
"This was the pair of boosters used on the historic first flight of X to Y" looks good on a museum plaque.
Re: SpaceX's Falcon Heavy center booster lacked ignition fluid to re-light engines
#73Earlier quoted context omitted.
Sure, but that system was in place for all the Falcon 9 relights as well. Presumably there's something different about the FH - minor architectural differences, flight profile, etc. - that caused this previously reliable system to run out.
The center core has a different structural design than the side boosters, which are stock F9 stages AFAIK.
Both of the side boosters were re-used for the Falcon Heavy launch. So stock F9s to some extent.
Re: SpaceX's Falcon Heavy center booster lacked ignition fluid to re-light engines
#74Earlier 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.
They also had to use TEB to re-light after an unstart [1]. I think 15 is abount right but it seems like a very small margin to deal with considering how common unstarts were.
Re: SpaceX's Falcon Heavy center booster lacked ignition fluid to re-light engines
#75Has 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?
They look a little more complicated than just a sheet of metal.
https://img.purch.com/h/1400/aHR0cDovL3d3dy5zcGFjZS5jb20vaW1...
Re: SpaceX's Falcon Heavy center booster lacked ignition fluid to re-light engines
#76He also announced the 3rd drone ship's name on twitter as "A Shortfall of Gravitas".
The 'Gravitas' thing is a running gag across the series. I'm glad they picked up on it.
For those unaware, the name came about when a competing civilization to the Culture complained that the Culture's powerful warships "ought to have names with more gravitas", and the Minds made a joke out of it.
I wonder if the same thing happened here. Maybe Elon saw someone complaining about his irreverent ship naming (both the ASDS and the "BFR") and decided to respond with this.
Re: SpaceX's Falcon Heavy center booster lacked ignition fluid to re-light engines
#77Perhaps some rocket scientist can explain why this seemingly-obvious error even happened? Shouldn't it be possible to calculate the precise amount of fuel used, and therefore required?
It's because there are very high penalties for carrying excess weight in aerospace, and the environment is uncontrolled. Imagine trying to calculate how much gasoline you need to drive from A to B which is 1,000 miles away, but for every extra fluid ounce of fuel you have at the end, you have to pay $10,000. You have to deal with varying weather, wind speeds, traffic and so on. How would you do this "precisely"? Let's remind ourselves that this rocket did 99% of its mission successfully, but didn't seal the deal.
Re: SpaceX's Falcon Heavy center booster lacked ignition fluid to re-light engines
#78Earlier quoted context omitted.
It says right there in the article that it used up the fuel while attempting to re-lights the engines (without success).
Sure, but that system was in place for all the Falcon 9 relights as well. Presumably there's something different about the FH - minor architectural differences, flight profile, etc. - that caused this previously reliable system to run out.
Elon mentioned that it’s heavier in the post launch press conference. But of course they would have used that information in their calculations...
Re: SpaceX's Falcon Heavy center booster lacked ignition fluid to re-light engines
#79They’ll learn and move on. All told it was a very successful mission and they got the money shot of the two other boosters landing back at the space center + putting the car in orbit. Very impressed with everything they’ve accomplished and can’t wait to see what’s next.
Re: SpaceX's Falcon Heavy center booster lacked ignition fluid to re-light engines
#80I bet it didn't randomly lack fluid due to some stupid miscalculation. It's probably more like: "Due to unforeseen circumstances it needed more fluid than expected. But we adjust our numbers and next time we expect more (in the hopes that it will be enough, which it will probably be)."
It says right there in the article that it used up the fuel while attempting to re-lights the engines (without success).
This was the original tweet: https://twitter.com/elonmusk/status/963107229523038211 that the article referenced but not linked.