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Nikxice
Active Member
Should be an easy engineering fix. It's not as though SpaceX hasn't seen the problem before.
N5329K
Active Member
Has SpaceX released enough information yet to conclude the post landing RUD was due to landing too fast,
which in turn was due to (unexplained) lower thrust than expected from the last engine running?
During the ascent video from inside the skirt showed one engine burning with a noticeably different color than the others.
Has there been any comment from SpaceX on this or suggestion there is a connection to the lower than nominal thrust
of the engine burning during landing?
which in turn was due to (unexplained) lower thrust than expected from the last engine running?
During the ascent video from inside the skirt showed one engine burning with a noticeably different color than the others.
Has there been any comment from SpaceX on this or suggestion there is a connection to the lower than nominal thrust
of the engine burning during landing?
I doubt we'll get that level of detail. People need to realize these are engineering test articles. Half of these ships are jury rigged. They are trying to test a few key things like flight attitude control and landing. Meanwhile the rest of the engineering team is also trying to build and test fuel and oxidizer pressure systems and those are rickety prototypes themselves. The point being is that this isn't like a Falcon 9 failure. Any F9 anomaly is well researched because no anomalies should occur. With Starship, it is a miracle if no anomalies occur. I wouldn't be surprised if every single major sub system had problems. For instance, the 4K slow mo video made it clear that the landing legs didn't even all lock properly.
-Elon
"SN10 engine was low on thrust due (probably) to partial helium ingestion from fuel header tank. Impact of 10m/s crushed legs & part of skirt. Multiple fixes in work for SN11."
-Chris B - NSF
"This is a tricky one given that I believe said helium pressurization was added to the CH4 header tank to mitigate what happened with SN8.
That's why it's a test program, of course."
-Elon
"Fair point. If autogenous pressurization had been used, CH4 bubbles would most likely have reverted to liquid.
Helium in header was used to prevent ullage collapse from slosh, which happened in prior flight. My fault for approving. Sounded good at the time."
"SN10 engine was low on thrust due (probably) to partial helium ingestion from fuel header tank. Impact of 10m/s crushed legs & part of skirt. Multiple fixes in work for SN11."
-Chris B - NSF
"This is a tricky one given that I believe said helium pressurization was added to the CH4 header tank to mitigate what happened with SN8.
That's why it's a test program, of course."
-Elon
"Fair point. If autogenous pressurization had been used, CH4 bubbles would most likely have reverted to liquid.
Helium in header was used to prevent ullage collapse from slosh, which happened in prior flight. My fault for approving. Sounded good at the time."
That is a great reply @Cosmacelf thank you. I knew they were moving VERY fast and expecting many RUDs along the way, but until your post I didn't appreciate how much many of the subsystems themselves are 'good enough for now' prototypes to enable testing of key capabilities. A miracle indeed!
Yeah, that's how Elon rolls. Back when they were learning how to recover the F9 first stage, Elon drove the entire team to attempt to do a drone ship landing well before they were ready. The first droneship landing occurred with a grid fin control system that used an open loop hydraulic fluid system. ie. the hydraulic fluid wasn't recaptured, it was just dumped overboard. Obviously this wasn't anywhere near the final design which would have to have a recapture system. Likewise the software to pinpoint land the ship wasn't anywhere near final - it had been designed and tested in something like 12 weeks of all out coding with engineers literally sleeping under their desks. Elon told his team that even if the chance of this patched together system actually landing was only 5%, it was still better than 100% chance of just losing the booster, and besides, they would learn a lot from whatever failed.
In the end, they ran out of hydraulic fluid (because of the jury rigged open loop) and crash landed near the drone ship. The software worked pretty well and they did indeed learn a lot from that first attempt.
The general public has no idea just how far out there Elon is. Nor, apparently, do his competitors. The latest dinosaur to not understand Elon's ideas was a German boring machine executive who dumped all over The Boring Company. I wish him good health in his retirement
e-FTW
New electron smell
Yup. Making water towers fly to 10 km, belly-flop and then land themselves is pretty darn incredible.
Buckminster
Well-Known Member
e-FTW
New electron smell
Never happens, but they’ll still try and come up with amazing solutions along the way that will benefit other projects or industries. I think we all under appreciate how much effort is put in to making air travel comfortable enough for our feeble senses and stomachs... Now imagine being in Starship that is getting caught by a movable structure.
Elon, please prove me wrong!
I could see them doing it to reduce weight on the earth to earth and earth to LEO versions.
At this point I suspect SpaceX has embraced variants of a core design vs a one size fits all.
-Harry
e-FTW
New electron smell
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