Nikxice
Active Member
I interpreted her message as sarcasm, venting disdain towards the program.
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NASA Announcement for the Moon
- Thread starter Grendal
- Start date
She is delusional.
I am willing to support national projects that serve a noble and realistic purpose but that does not mean such projects have license to be inefficient and unsustainable.
e-FTW
New electron smell
I encourage you to resist the temptation to conflate the merits of a concept with the inevitable reality of its execution as a state run project.
While I personally believe the SpaceX single shot solution has the edge on all fronts, it is NOT because an assembly in space is an inherently bad idea (and it is certainly not 'lunacy'). There are legitimate technical, cost, and schedule pros to multiple launches over a single shot. As an example, structural loads increase with size--a big starship has to be built around surviving a few minutes of earth launch and, like a big building that requires a bunch of steel (vs say, a shed made out of plywood and 2x4's), a big starship will be a formidable structure. Smaller, 'dumber' modules can be much more rudimentary in design (2x4's and plywood purchased from Home Depot, so to speak), they can leverage economies of scale, and their on-orbit coupling concepts can be quite minimal because structural loads in space are a fraction of those during launch. Somewhat related, the external form factor of a single shot solution is dictated by those same few minutes of earth atmosphere; the remaining multi-year mission must conform to the limitations of that geometry (unless we're talking inflatables, but that's another conversation). A multi-module space vehicle can be a free-form optimization with minimal dimensional constraints.
To use a space analogy, this is similar to the GEO (single Mars shot) vs LEO constellation (assembly-in-space) trade that's ongoing in the industry--a trade that doesn't seem like its ever going to have a binary result. It's not even that different from SSTO vs staged.
Also, using the ISS build duration as justification for 'lunacy' WRT assembly in space is false equivalency. Besides the sociopolitical intent of that project, it was always meant to be built (and upgraded, and re-imagined) over a long period of time. There was never any element of expediency to 'finishing' the ISS.
I see your points. But isn’t the main goal to reach the moon and setup installations there? If there is a single-shot solution like Starship with immense flexibility on type of cargo to transport directly why not just save all the funding for creating moon habitats and supporting technology?
It is immensely costly and time consuming to setup all the infrastructure just for getting there - hard to understand when there are other solutions on hand. Why not just keep it as simple as possible?
I think this is what @ecarfan meant with lunacy.
It is immensely costly and time consuming to setup all the infrastructure just for getting there - hard to understand when there are other solutions on hand. Why not just keep it as simple as possible?
I think this is what @ecarfan meant with lunacy.
That "lunacy" comment was in the context of doing the assembly at LOP-G with Mars the ultimate destination. I also think that makes no sense at all.
If by "assembly" you mean multiple modules automatically docking together, then yes, that seems quite doable. However, if by "assembly" you mean actual construction in the ISS sense, I'm pretty doubtful. We're not very good at that yet, especially if a lot of space walks are required.
If by "assembly" you mean multiple modules automatically docking together, then yes, that seems quite doable. However, if by "assembly" you mean actual construction in the ISS sense, I'm pretty doubtful. We're not very good at that yet, especially if a lot of space walks are required.
The bigger picture point is that the trade isn't binary. Finding one 'best' solution doesn't immediately render other concepts utter crap.
Consider, for instance, if SpaceX were to undertake the multi-module concept as opposed to NASA. Napkin math says you need 7 F9's to rack up to the ~mass and ~volume capability of a super heavy, and near as makes no difference for this discussion, ~$600M to launch all of them. The Starship is going to cost billions to develop--I think $2B is the low number from Elon? So if you're the banker, you're looking at a solution with a fully developed, fully amortized, reliable workhorse that's ~$1.4B cheaper than just the development cost of a brand new launcher. I couldn't say for certain, but I'm going to bet that SpaceX could easily pay for development on in orbit assembly, delta-v inefficiencies, etc, and all the other 'extra stuff' that are needed for the multi-module concept with $1.4B in the bank. Then you theoretically end up with a persistent waypoint for future missions, further reducing their cost. And on top of that the multi-module mission also breaks down risk into smaller, more manageable chunks than a single shot.
Ultimately, IMHO at least, the single shot still takes the win in the trade, primarily because it leaves you with a [presumably] cost effective super heavy lifter; it's a solution that looks farther into the future, as it were.
Agree, although I think the latest rumblings from Elon are that full metal Starship will be much lower cost to create.
Realizing, of course, that first article and development costs are different than unit 200's cost.
Yeah, for sure...then again Elon also said a Falcon 9 could be as low as $4M or something, so....
Anyway, I'm going to guess that it will take a least a handful of launches to get the true average cost under $1B, and then 10 or more to get under $250M. Reusability will ensure that steep curve, so that's good, but its still a lot of work.
There's also a F9 2.0 (or equivalent, be it within SpaceX or BO, etc) element to be considered. F9 will assuredly get new tech trickling down, further improving its cost efficiency.
Who knows, maybe internal cost is that low...
I thought he was taking about the cost build a Starship, not the per-launch cost. Probably a lot of tooling and wages (and hopefully not many prototypes) to amortize, but it seems they'll be sub Billion from this point (not that I have a real clue).
Do you think they'll still iterate F9? I though that was going to stay as is, running each core as many times as possible, and all R&D effort focus on its replacement.
My farmer's math was total amortized cost, so NR+REC/launches. I could see recurring cost starting in the hundreds of millions and then pretty quickly dropping to tens of millions.
I personally see it as an evolutionary trip for F9 as as opposed to a ground up replacement. More model S-->X than S-->3, so to speak. It's hard to imagine a ground up outperforming variants (and I'm talking variants like a raptor retrofit) enough to warrant that ground up in the first place. Especially until some crazy new Star Trek tech is developed, and especially once SpaceX can successfully recover all major launcher elements, I can see F9 being the Soyuz of this century. (Given the state of the Russian space program I can see the Soyuz being the Soyuz of this century too, but I digress...)
From an earlier SpaceX talk, I thought F9's days were numbered due to Starship's higher capacity, full reusability, and lower per over mission cost (the Helium costs more than the fuel it pressurizes).
I think this is one of those places where the reality of space supersedes waxing from SpaceX. I think when you layer the practical timeline of cost-effective recurring Starship launches, the likelihood of trickle down upgrades into F9, and most importantly the practical demand for super heavy launchers over the next decade or two (which will be relatively low), it is very unlikely you'll see F9 pushed out of go-to workhorse status.
FWIW...
Responsing to question about how many launches they can get per rocket:
Elon Musk on Twitter
Regarding number of booster in fleet:
Elon Musk on Twitter
As skeptical as I am about Elon's predictions (VERY!), I can see a plausible way BFR could be cheaper per launch than F9. If the cost per launch were cheaper, it would make sense to launch a single 500 kg satellite on BFR rather than F9 and leave the rest of the "hold" empty.
AFAIK, the costs are more or less:
The real wild card though, IMHO, is: how elastic is the market for heavy launches? Currently, pre-F9H, heavy launches are very expensive with few non-government takers. However, if the cost comes down significantly, even though it's a single source, I'm unconvinced people won't take advantage of it. If they do, the market might expand significantly. If New Glenn does what's claimed, perhaps BFR wouldn't be single source either.
AFAIK, the costs are more or less:
- Launch prep/integration
- Range
- Fuel
- Recovery
- Refurb
- Replace expendable parts
- Amortization
The real wild card though, IMHO, is: how elastic is the market for heavy launches? Currently, pre-F9H, heavy launches are very expensive with few non-government takers. However, if the cost comes down significantly, even though it's a single source, I'm unconvinced people won't take advantage of it. If they do, the market might expand significantly. If New Glenn does what's claimed, perhaps BFR wouldn't be single source either.
1 would be less, if the fixed launch mount comes to fruition. Likewise 4 would be negligible since the first stage lands back on the mount and the second stage lands nearby.
3 may be less due to no helium needed, additionally O2 and methane can be made via solar power.
6 is a huge save, reuse of second stage and no lost fairings.
I expect that Starship program will be a bit like what happened with reusability with SpaceX (F9 and especially FH). SpaceX will need to showcase that the system works then we'll slowly see adoption from the major players and it will take years for manufacturers to take advantage of the new abilities the system represents. SpaceX will do trips around the Moon and at some point land there with NASA along for the ride in a tentative way. Sadly, NASA and others are just too married to the old school political realities to jump fully onto the SpaceX future.
Yeah, for sure there's a limited life on each booster, and for sure F9 will be obsoleted at some point. I just don't see the space industry creating significant demand for a super heavy over the next decade or more. Similar to the predictions that there would be like 50 falcon 9 launches in 2018 (or whatever the predictions were) we're basically listening to just one side of the story. In reality, a significant portion of the success/frequency of Starship launches are going to be based on non-SpaceX entities, and none of those entities can (or want to...) transition as quickly as SpaceX into a new paradigm of space production. At the risk of stating the obvious, a super heavy is most effective at launching 1) heavy things and 2) a lot of things. So the exercise is then looking at what portion of the next decade+ of launches are going to fall into one of those categories.
On the commercial side the constellations are clearly having a hard time securing funding, so the launch demand is slipping out. On the other side of the spectrum the legacy operators are all sitting on their thumbs waiting to see what the constellations do before ordering mega GEOS (they're not really, but humor my hyperbole...). Bottom line though, its kind of a waiting game to see what takes off, and then when something happens there will be plenty of ramp up time.
On the government side there's much less total quantity of significant space assets, they take forever to conceptualize and produce, and its hard to imagine more than handful will actually require the super heavy class (~Starship, ~NG, ~SLS). Government is of course intimately tied to funding, and so its also hard to imagine a windfall of space budget coming anytime soon that could enable a mega thing that requires super heavy in the first place.
Other constellations aren't even a slam dunk--most of the constellation proposals out there are significantly smaller than The Big Three, and those that have many tens and occasional hundreds of units involve fairly small spacecraft. So at that point there's probably a legitimate reason to consider multiple single plane F9 launches versus one (or a small number of) Starlink launches that have to inefficiently adjust inclination on orbit.
Don't get me wrong--total lifted mass and total number of assets are obviously going to ramp up over the next decade+, and Starship will absolutely play a part in those metrics. I'm just not convinced it will be as significant as implied.
Long story longer, note that I'm skeptical about Elon's 'less than F9' cost prediction for starship in general--I could be wrong, but I suspect he's really talking about cost/mass, and if the big rocket is only fractionally more cost efficient than the small rocket, most people are actually going to prefer the small rocket up to the point where they can't fit on it anymore. And anyway, what was the low number from Elon on F9? $4m/launch?
e-FTW
New electron smell
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