The record for mass delivered to LEO in a single launch was the Apollo 17 mission, which lofted 141 tons. Uprating Starship by 20% would mean a 180 ton payload in its reusable configuration and 300 tons if expended.
“Scotty, I need more water pressure! Maximum pressure! Divert all auxiliary power to the pumps!”
Wow. Elon Tweeted earlier about the test at 350 bar, saying the engines really wanted to melt... which made it sounds like this was an "upper limit test". That test equated to like 592K lbs of thrust.
I was wondering about that as well. Either they discovered something new as a result of testing the engines to their limits - or this is what you get from an expendable Starship, where they'd push the engines so hard that they produce almost 20% more thrust - but only for one run.
Would that be enough pressure for the "showerhead" effect described for the plate?
A napkin calculation on the rocket thrust using the current 6000 ton thrust level across the 9 meter diameter rocket diameter says that the plate will be hit by a pressure of 127 psi. So if the water is supposed to keep the plate free of thrust impingement, they're going to need something in that ballpark. Using the pressure calculator, the water would have to be 300' above the plate. The tallest water tower in the US is 216'. I guess SpaceX has had enough of towers for a while.
It appears that SpaceX will be using pressurized nitrogen to force the water through the deluge plate holes, based on the racks of high pressure tanks associated with the large “hot dog” water tanks for the deluge system.
I want one of those for my bathroom!
By my back-of-a-napkin maths, that's an extra 20 000 Newtons of thrust at lift-off.
