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Can someone explain the seemingly big drop of payload capacities of New Glenn from LEO's 45t to GTO's 13.6T? That is GTO/LEO=30% for a two staged rocket. Falcon 9 FT is 36.8%. Although Kerosine 1st stage gives Flcon 9 advantage, but Hydrolox 2nd stage should give New Glenn advantage too. So I would expect New Glenn to be at least equal to Falcon 9 or even better (if payload does not scale linearly with overall mass).

BTW, the figures for New Glenn are from their user guide and are final design spec, not temparory figures of prototyping.

iewgnem said:

Also keep in mind you can't just stack more and more mass without increasing diameter or change fuel, at some point you'll reach the physics limit of engine chamber pressure with a given fuel chemistry. Right now they're basically betting everything on Raptor 3 and Starship v3, and even then I would not be surprised if final performance is not much different than Long March 10, and achieved after Long March 10

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I guess you meant CZ-9 which is in the same league as starship.

iewgnem said:

As for Blue Orgin, New Glen is a properly engineered rocket, certainly better than Starship, but its LEO lift is half of LM10, and it's GTO / TLI performance is actually lower than LM5, i.e. it wouldn't even be able to launch Chang'e 5 at 8,200 kg to TLI... Yeah they're betting on in-orbit fuel depot too, but counting on it to pull off manned lunar mission is asking a lot.

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Are you talking about CZ-10 or 9? New Glenn's LEO is 45t (200km, 51.6 degree), CZ-10 is no less than 70t, so New Glenn's LEO is well above half of CZ10. If you are talking about CZ-9, then its LEO is 150t, then New Glenn is less than 1/3 of it.

Xiongmao said:

I think the worst nightmare scenario that NASA should strive to avoid is the prospect of astronauts stranded on the moon because the Starship toppled over or the engines fail to reignite to lift back off the surface. The more they rush, the less time they have to prepare for contingencies. Also, the SpaceX methodology, that is to do adopt an agile approach to development, doesn't provide much comfort when you are quarter of a million miles from Earth.

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I think NASA's mentality now is the same as the time when they decided to skip escape system for space shuttle, "we will have to make it (starship HLS/shuttle) much much more reliable". I won't comment on that as history has told us.

Further more I think NASA is gambling that in the first moon landing everything works and they immediately stop further moon missions and call a win (beating China for the 1st). They are betting on that just like shuttle's high risk did not menifest in the early missions. Afterall the whole rush is more about political statement than science ever since Obama's time when US found that China's moon program is catching up quickly.

Lastly and also what I am really curious of is what SpaceX' thought is of landing a skyscraper like HLS on an uneven and not-leveled moon surface without all the landing aide becons and assistance guidance systems on earth.

taxiya said:

I guess you meant CZ-9 which is in the same league as starship.

Are you talking about CZ-10 or 9? New Glenn's LEO is 45t (200km, 51.6 degree), CZ-10 is no less than 70t, so New Glenn's LEO is well above half of CZ10. If you are talking about CZ-9, then its LEO is 150t, then New Glenn is less than 1/3 of it.

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Nope, I meant LM10 at 70 ton. Run the numbers yourself using velocity-altitude curve from their streams, see how much takeoff mass they need to add to go from suborbital to minimum orbit with no payload, how much takeoff mass for +20 ton payload, and verify that with performance delta after they added 25% upper stage fuel on v2. Remember v1 couldn't even make orbit with no payload and it was denied until v2 and v3 were announced.

For New Glen, sure 45 is more than half of 70, but not by enough to change calculus on lunar missions.

taxiya said:

Can someone explain the seemingly big drop of payload capacities of New Glenn from LEO's 45t to GTO's 13.6T? That is GTO/LEO=30% for a two staged rocket. Falcon 9 FT is 36.8%. Although Kerosine 1st stage gives Flcon 9 advantage, but Hydrolox 2nd stage should give New Glenn advantage too. So I would expect New Glenn to be at least equal to Falcon 9 or even better (if payload does not scale linearly with overall mass).

BTW, the figures for New Glenn are from their user guide and are final design spec, not temparory figures of prototyping.

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Remember LM5B's 21-ton core stage goes into orbit with payload.