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Sunday 4 June 2023

Comment on Starship Orbital Test Flight Raises Serious Questions by Jim Hillhouse

In reply to spacerfirstclass.

That’s not the way I see it. Nor increasingly by people within NASA that I talk to. Far from it.

Here are my point-by-point rebuttals.

– Blue Origin’s contract is for a lander for later Artemis missions starting in 2029. Which leaves about a 2-3 year gap, if all goes well for Blue, between SpaceX’s scheduled landing for Artemis III sometime in 2026 or so. I do applaud NASA making this agreement.

– SpaceX doesn’t need gov’t help
You should take to guys at NASA who work with SpaceX. They need help. A lot of help. With Starship. Filling-in craters is one thing. Getting permission to launch again is another. Are you on the FAA mishap team? Me neither. So let’s wait and see on this. Also, keep an eye on the DC Circuit Court.

– SHB FTS activated after all
How long did it take the Booster FTS to actually destroy the vehicle? A minute? A minute and a half? Two minutes? And given that time gap, how far would the Booster travel had it been oriented on a trajectory towards say, Brownsville? Most…no, all FTS’s seem able to disassemble a launch vehicle in a few seconds because they have strip charges that split the vehicle wide-open. Not so with SHB. And why not?

– Starship Abort Capability
So, let me see if I get this straight. Elon said that the abort capability of Starship wasn’t enabled because that would affect its mission to land in Hawaii? Seriously? How? I mean, Orion has a LAS, and its service module is a later stage of launch abort system, and that doesn’t seem to affect its ability to orbit the Moon. How does enabling the abort system of Starship affect its ability to subsequently proceed in other mission activities? Or are you telling me, without realizing it, that SpaceX doesn’t yet have the launch abort capability enabled because it hasn’t yet been developed? More likely than not, that’s the reason.

– Orion depends on Lockheed Martin – a single company, SLS core stage depends on Boeing – a simple company, SLS booster depends on Northrop Grumman
Did you know that all of those elements are owned by the government, NASA in particular? That SLS is produced in a government owned facility, Michoud? That the government could take the blue prints of any one of those systems, give those to another contractor, and award a contract to build that system? That is patently not the case with any of the commercial entities save only if companies file for dissolution, provided that a substantial amount of their funding came from NASA. If SpaceX tomorrow decided to cease Dragon development, absent a clause in the lunar lander contract with NASA, the space agency would be at a complete loss and back to square one on a lunar lander. Well, given where SpaceX is, NASA sorta already is.

–Starship Lunar Lander has a descent abort capability
Really? What would that be. I’d sure like a document referencing it because my NASA sources at several centers tell me otherwise. But I am 110% confident you don’t have such a document because the descent abort capability doesn’t exist. Instead, if something goes wrong on a Starship Lunar Lander during descent, the abort capability is for the astronauts to (hopefully) have enough time to say good-bye to their families while they wait to become permanent monuments to human spaceflight.

I’m going to penultimately close by noting that Elon is about as straight a talker as a circle. Breathlessly repeating what he says as your “evidence” isn’t going to change many minds, save his fan club. Having followed him since the early 2000’s, I can say he is pretty much a constant stream of BS. Don’t agree?

Let’s walk down memory lane towards several years ago, to 2015, to recall Elon’s Red Dragon PR stunt. Why is it BS? If you know the optimal trajectory windows for Earth-Mars missions, you needn’t ask. See AIAA 2011-7216. Per that paper, “The orbital mechanics cycle of the Earth and Mars has a period of 15 years, and a minimal delta-V phase of the cycle in the early 2030’s.” For a vehicle even half as heavy as a stripped-down Dragon, during 2015-2019 it would have been extraordinarily difficult if not impossible for even a FH to launch Red Dragon with enough propellant to enter and land on Mars and then have a smaller payload launch from Mars and get back to Earth. Where’s Red Dragon? Probably same place as Cyber Truck, FSD, Twitter, and so on.



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