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Old 06-12-2019, 04:12 PM   #23
Join Date: Jul 2008
Default Re: Approaching TL9?

Originally Posted by AlexanderHowl View Post
I can guarantee you that the each stage is not getting an ISP of 480. A delta-v increase of 2.52 mps (~4.04 km/s) is an ISP of 412, which is well within LOX/LH2 design parameters. The first stage of the Saturn V used RP-1/LOX, so it had only an ISP of 263, but the upper stages used LOX/LH2, so they had an ISP of 421.
You can guarantee anything you want to, but the stats you gave with stages getting 3.12 mps off of a 65% fuel mass imply an Isp of 488 seconds.
I don't know any 3e, so there is no chance that I am talking about 3e rules by accident.
Ulzgoroth is offline   Reply With Quote