NASA says SpaceX’s next Starship flight could test refueling tech

The series of failures when attempting to land for the first time was spectacular.

Suppose that the eventual production vehicle has a fairly different design, a different name, and it succeeds on its first flight. Would it then have used the same methodology that resulted in Falcon 9?

I'm only asking rhetorically. The Ship of Theseus is an interesting philosophical question, but the way you define "methodology" shouldn't depend on your answer.

https://www.nasa.gov/directorates/somd/space-communications-...

Software produces gobs of money, the likes of which the world has never seen. Aerospace as an industry may not ever be profitable. It's as easy as that.

Looking at the Western space industry history, Starship development is only comparable to the Apollo or the Space Shuttle program - both of which would be insanely expensive in 2023 dollars, certainly exceeding 100 billion USD each, perhaps 300 billion USD in case of Apollo.

The big issue is that unlike all fuel that has been moved between tanks in microgravity in the past, SpaceX isn't storing their fuel in a flexible tank. Instead, they have the fuel and the pressurant gas in the same tank. Under acceleration (gravity or otherwise), this is not a problem, because the fuel pools naturally "down", with the pressurant above it.

However, as soon as the acceleration stops, there is no more down. Instead of having a bunch of fuel on the bottom and pressurant above, the tank will contain a chaotic mixture of floating gas and liquid.

The minimum setup for fuel transfer is a maneuvering system capable of a very long, weak impulse (to provide down), and then some kind of pump that moves fuel, because the force provided by the weak impulse of a maneuvering thruster is not enough to do it on it's own.

Literally KSP career mode IRL

Are you referring to Starhopper? It is still present at Starbase as of recently.

https://www.google.com/maps/place/Starhopper/@25.9977631,-97...

This is still the number one problem with Starship. There were all these wild claims of an exotic new liquid cooled reentry system at the beginning. But because physics they ended up going right back to using ablative. They'll suffer the same fate as the shuttle for it. Nothing has fundamentally changed in ceramic or adhesive technology since then, and the lack of aerodynamic control means they will have to survive even steeper descents with greater thermal load. I imagine the idea of Starship as an earth return vehicle in general will probably be abandoned, so they can optimize it for interplanetary transport and lunar operations.

Because this will be the first time in history that the cost of a launch will be mostly the cost of the fuel. This is the first fully reusable rocket in history. If you had to throw away a dozen tankers it wouldn’t make any sense.

It makes the notion of ss cans supporting Mars colonization a bad joke. The cans might be just barely adequate to support a Lunar outpost. The "gateway" concept is another bad joke. It is in plans solely because that is the closest to the moon that SLS can get to. It isn't legitimately a gateway to anything: stopping there makes getting where you really want to go substantially harder. The only legitimate place for a gateway would be in high Earth orbit, because it wouldn't require extra fuel to stop at it and then get moving again.

https://www.youtube.com/watch?v=OoJsPvmFixU

The other thing he mentioned was the Apollo success playbook (SP-287), "What Made Apollo a Success?"

https://ntrs.nasa.gov/api/citations/19720005243/downloads/19...

Link to EPUB version https://old.reddit.com/r/SmarterEveryDay/comments/18aw4ca/i_...

At it's peak, the Apollo project was funded to the tune of 1.1% total US federal outlays during the time period it ran. That's an enormous amount of money, which failed to produce a remotely sustainable result. You got what you got: moon landings done quick, and then never again.

The modern Apollo project is SLS which...is a big, expensive, absolutely cannot fail rocket (which is really a jobs program for preferred contractor districts, with technology choices decided by politicians not engineers).

Basically the SED lecture spends a lot of time gesturing at Apollo, but never addresses the actual problem which is NASA is funded the way it's funded: of course they know they're going to miss their launch dates, they're not funded to hit them, and they're probably going to wind up redesigning the mission once Starship is flying to orbit and actual performance numbers are realized off-paper. The SLS is the SLS for the same reason: at the time the program started there was no SpaceX, nor Space Shuttle and it was something of a national embarrassment the US didn't have a manned space capability but the Russians still did.

In short, for a lecture which opens talking about people worrying about disagreeing with their superiors, he stays well away from the actual live-wires of the issues.

The SmarterEverDay concerns about the orbit seemed to be that while landing or taking off maneuvers were short & low energy (good), it meant the opportunity only came about every couple days (bad).

SED also stressed that Artemis is relying on crulyonic fuel transfer. SED repeatedly pointed out this is a tech that has never been tested, ever.

The problem of "we need to get off the moon now" is "okay, but where are you going and what's going to be there that's more useful then where you are?"

It's not unreasonable to note that a medical emergency would be much better dealt with on the moon - where you have gravity - then in orbit, where you don't. Whereas if you need to bail out and get to Earth fast (which you can't) then you'd be better off just dropping a vehicle which can do that onto the surface.

There were already programs like NERVA in development for an advanced nuclear upper stage. Once you have that, making the Upper Stage refuel-able, makes it basically into a multi-use space tug for cis-lunar.

Then you could evolve Saturn 1B into a reusable Saturn 1C, just like Falcon 9. That gives you a reusable heavy lifter. And it would also safe a gigantic amount of money that was spend on Atlas/Titan/Delta in the next 40 years.

The Apollo capsule was not reusable but continuously evolving a capsule design in that direct was certainty possible. But its not the most important part of the system in terms of cost.

What really need more development is the lander itself. Making a large reusable lander would have been costly but not really out of reach.

You can use an occasional Saturn V for large things like Skylab and special deep space mission.

That was a much better path forward then Space Shuttle and ISS.

"The Apollo lunar base proposal saw an uncrewed Saturn V used to land a shelter based on the Apollo Command/Service Module (CSM) on the Moon." <https://en.wikipedia.org/wiki/Apollo_Applications_Program#AE...>

Also the argument taken to an extreme is straightforward. We know that massive catastrophes have caused mass extinctions that wiped out most life on Earth. This is clearly visible in the fossil record. Ergo, one of these is certain to happen again. In the extremely long term, the Sun will get hot enough to kill all life on Earth in a couple hundred million years. So Humankind is doomed if we do stay on just Earth for the very long term.

There's also the side argument that "right now" appears very close to making it possible. If Starship and the attempt at reusable rockets were to disappear there's nothing guaranteeing the progress of space technology. It's easy to see a future where we do some more footprints on the Moon and maybe later some footprints on Mars, but no permanent off-earth colony is ever established. Eventually we give up on creating such bases because they're deemed too expensive and "robots do it better" as our robotic technology gets better and better. The technology of how to do reusable vehicles is eventually forgotten over several generations and then we never leave Earth again. (Eventually resulting in our destruction.) This is a "why not now?" argument.

The path to making colonies on Mars or the moon self sustaining is not even clear at this point. Starting with the simplest of fundamentals - air, water, food and protection from cosmic radiation. The prospect of growing a technical civilisation on either body, that can develop further without support from Earth is remote.

By contrast, to make earth unlivable basically means nuclear war. Climate change won't do it, biological pandemics won't do it, nor will fossil fuel exhaustion or any other localised event.

On the worst day possible on earth (global radiation aside) its still a million times better to live on than anywhere else.

In terms of global radiation making the world uninhabitable even then tiny, non-sustaining pockets of humanity would survive. At least until their life-support systems failed.

Lastly, I wonder at the need for "the future of mankind" as a goal at all.

(We should probably start with the moon, though)

While NASA Administrator, Michael Griffin wrote in 2007 that the shuttle program had been a colossal mistake and that Apollo-Saturn-Skylab should have continued <http://aviationweek.typepad.com/space/2007/03/human_space_ex...>:

>Let’s assume that we had kept flying with the systems we had at the time, that we had continued to execute two manned Apollo lunar missions every year, as was done in 1971-72. This would have cost about $4.8 billion annually in Fiscal 2000 dollars.

>Further, let us assume that we had established a continuing program of space station activities in Earth orbit, built on the Apollo CSM, Saturn I-B, and Skylab systems. Four crew rotation launches per year, plus a new Skylab cluster every five years to augment or replace existing modules, would have cost about $1.5 billion/year. This entire program of six manned flights per year, two of them to the Moon, would have cost about $6.3 billion annually in Fiscal 2000 dollars. The average annual NASA budget in the 15 difficult years from 1974-88 was $10.5 billion; with 60% of it allocated to human spaceflight, there would have been sufficient funding to continue a stable program of lunar exploration as well as the development of Earth orbital infrastructure. I suggest that this would have been a better strategic alternative than the choices that were in fact made, almost 40 years ago.

I think this kind of misses the point of the video, which was not about the technology of Apollo as much as it was the design principles that went into making the mission a success. Technology obviously is involved in that, but the argument for "do it like Apollo" is more a long form version of "keep it simple, stupid".

A good example of this is when Destin brought up the Apollo 1 capsule fire[1] which changed the speed and safety considerations at NASA. He cautions that now, before a catastrophic accident, is the time to make sure the best possible plan is being followed, simplify things that can be simplified, and get people to the moon and back safely. Something as simple as the choice to not use hypergolic fuels means there will need to be extra equipment to reignite the engines and redundant mechanisms for such a system.

1. https://en.wikipedia.org/wiki/Apollo_1#Accident

SpaceX sold launches at around 60-70 million $ and that made it profitable. Once the proved out reuse, they were able to get investors. My contention is that unless they could actually show reuse they could have never raised they amount of money they did, it wouldn't make sense.

Another way of thinking about it is, what based on basic principles is the cost of building these things. Various people have estimated this stuff. 20-30 million $ for the first stage with engines, 5-15 million $ for the second stage, 6 million $. Probably 20-30% overhead for operations and fixed cost.

Now things are different. The first stages are going on 20 reuses. The second stage is now being mass produced pretty significant volume, so price goes. Fairing are reused also. You have the same size operations team that is far more efficient. A team that used to do 10 launch now does 50 launches. Moving to automated range safety is one big such optimization. The launch pad utilization is far higher.

So most people who look at this come out for with a marginal cost of about 15-20 million $ per launch. You can be conservative and say 30 million but it hard to come up with reason why it should be so high. At the same time they are still selling launches at 65 million. And in addition to that, they have many special launches that are likely earn them more, DoD launches, NASA launches, Crew launches and Falcon Heavy launches.

So I think it really, really hard to argue that SpaceX core business isn't very profitable. You would basically have to claim that first stages get totally rebuilt from the ground up and all engines replaced. But we have very good evidence that this isn't the case.

Now of course that doesn't mean SpaceX is profitable, as thanks to the re-usability success, they invested heavily in Starship and Starlink. And those are of course unprofitable investments for now. Starlink is starting to turn around, but Starship is quite a bit away from that.

What can maybe be argued is that if you only had say 10 launches a year, re-usability wouldn't be worth it for various reason.

But it would seem pretty foolish for SpaceX to be continually reusing rockets this much if that cost them extra money?

(I mean extra vs building new ones)

Test flights are a very different beast. Early tests can be expected to fail; some are supposed to fail ("destructive testing"). Explosions and other failures become much more concerning later in the process; for example, Boeing's Starliner's latest test flight was supposed to demonstrate everything was working correctly. It failed to do so.

In the two Starship launches so far, SpaceX was very clear with expectations in advance. Each likely has dozens of objectives. The second flight very clearly accomplished more than the first; a successful test of the launchpad mitigations, a successful test of all first-stage engines staying lit, a successful test of separation, a successful test of the second-stage engines all lighting, etc.

The success criteria for integrated launch test 1 was to clear the launch pad (which it nearly destroyed) test 2 was get past the stage seperation, which it did.

Spacex have a very fast cadence for tests and seem not to make the same error twice. The best test environment is really trying to fly the ship.