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The chart is tons to LEO. Saturn V wasn't designed for LEO, but it certainly could have dropped that much there. (Skylab used a pretty fair fraction of that cap

The chart is tons to LEO. Saturn V wasn't designed for LEO, but it certainly could have dropped that much there. (Skylab used a pretty fair fraction of that capability.) When you're comparing launchers you have to pick some baseline target orbit. LEO is a good lowest common denominator, but isn't quite fair as launch systems optimized for higher energy orbits (like the Saturn V) lose some of their advantage. But a higher orbit is even less fair to systems designed for LEO; choose anything else, like GEO or lunar insertion, STS would have a big fat 0.

avmich 6y ago
Yeah, I know, but the point is Saturn V is shown as carrying to LEO 140 tons - and 140 tons was actual translunar payload (Apollo CSM + LEM, ~45 tons) plus dry 3rd stage (~15 tons) plus unspent fuel in the 3rd stage (about 2/3 of initial load of 105 tons of fuel). At the same time Space Shuttle doesn't show the empty mass (a lot) and unspent fuel (very little) of Space Shuttle "second stage", which is Orbiter, and mentions only payload in the bay of that Orbiter. We could arbitrarily say Energia brings 0 tons on orbit - because it's, strictly speaking, a suborbital rocket, the payload needs to add some ~100 m/s of velocity to get to orbit, this was done to avoid getting empty stage to orbit (so no littering, no necessary maneuver to deorbit). Or, alternatively, we could say Energia brings 170 (!) tons to LEO - indeed, if one pays no attention to factual suborbital speed and adds mass of empty 2nd stage of Energia, which is 78-86 tons (http://buran.ru/htm/rocket.htm http://buran.ru/htm/rocket.htm), one gets this number. So it's important to carefully compare similar things. 140 tons for Saturn V is too different from 27 tons of Space Shuttle by method, not by result.
- ggm 6y ago
  Thank you for a well reasoned argument. I would love some formalism of actual useful lofted weight, vs apparent weight lofted to some stated orbit. Getting 27 tonnes to LEO but leaving 50 tonnes in unstable orbit is not 77 tonnes of useful loft, to me (fictive example)

avmich 6y ago

Yeah, I know, but the point is Saturn V is shown as carrying to LEO 140 tons - and 140 tons was actual translunar payload (Apollo CSM + LEM, ~45 tons) plus dry 3rd stage (~15 tons) plus unspent fuel in the 3rd stage (about 2/3 of initial load of 105 tons of fuel). At the same time Space Shuttle doesn't show the empty mass (a lot) and unspent fuel (very little) of Space Shuttle "second stage", which is Orbiter, and mentions only payload in the bay of that Orbiter. We could arbitrarily say Energia brings 0 tons on orbit - because it's, strictly speaking, a suborbital rocket, the payload needs to add some ~100 m/s of velocity to get to orbit, this was done to avoid getting empty stage to orbit (so no littering, no necessary maneuver to deorbit). Or, alternatively, we could say Energia brings 170 (!) tons to LEO - indeed, if one pays no attention to factual suborbital speed and adds mass of empty 2nd stage of Energia, which is 78-86 tons (http://buran.ru/htm/rocket.htm http://buran.ru/htm/rocket.htm), one gets this number. So it's important to carefully compare similar things. 140 tons for Saturn V is too different from 27 tons of Space Shuttle by method, not by result.

ggm 6y ago
Thank you for a well reasoned argument. I would love some formalism of actual useful lofted weight, vs apparent weight lofted to some stated orbit. Getting 27 tonnes to LEO but leaving 50 tonnes in unstable orbit is not 77 tonnes of useful loft, to me (fictive example)