Thread: SN10
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Old March 26th 21, 06:48 AM posted to sci.space.policy
snidely
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Default SN10

David Spain pounded on thar keyboard to tell us

Several design changes in the works for SN11.


SN11? Probably not any major change. SN15 is supposed to be the 1.1
release.

I suspect a total re-think of
the helium pressurization setup for the header tanks. Perhaps some new form
of autogenous pressurization, along the lines of a cascade dual
pressurization scheme, whereby the header tanks are placed under higher
pressure than before from the engines and then that is used to prevent ullage
slosh, while the engines are off during the belly flop. Not sure why Elon
went the helium route in the first place on SN9/SN10. It's going to be more
complex in some ways than the helium scheme but hopefully and somewhat
un-intuitively more reliable.


It was a quick fix to the low header pressure problem of SN8, of
course. And it wasn't so supposed to be the permanent fix, so SN15
could be a *revised* autogenous pressurization scheme; after all,
they've had 3 months to do fresh engineering.

/dps

--
"This is all very fine, but let us not be carried away be excitement,
but ask calmly, how does this person feel about in in his cooler
moments next day, with six or seven thousand feet of snow and stuff on
top of him?"
_Roughing It_, Mark Twain.