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0 pointsjakeinspace2y ago0 comments

I might be off here, but I think the super heavy booster actually puts out more power than 3 Gorges. At stage separation, the booster and starship were moving at ~5500 kph, or about 1500 m/s. The nominal maximum thrust of the super heavy booster is given as 75,000 KN on Wikipedia. Possibly that level of thrust is only happening ar liftoff, I’m not sure, but if the engines were still burning that hot at stage sep, then that would give an instantaneous power output of 75,000,000 N * 1500 m/s = 112.5 GW.

Edit: misread your comment, we’re in agreement. But I’ll leave the arithmetic.

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Retric2y ago

Right ballpark but missing a few important caveats. Rocket engines generally throttle down to maintain a constant acceleration, otherwise you need to add more structural support to the following stages which costs weight.

Also, calculating power output like that is misleading. A solar powered ion engine on a probe has constant solar power and constant acceleration but would have increasing calculated power output over time as it keeps accelerating. What’s going on is rather than the engine being more powerful the propellant starts with more kinetic energy.

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0 pointsjakeinspace2y ago0 comments

Edit: misread your comment, we’re in agreement. But I’ll leave the arithmetic.

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Retric2y ago

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