Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Starship is still not understood

caseyhandmer.wordpress.com

Post reply on HN
Print view View original

181–190 of 364 posts

Re: Starship is still not understood

#181

Post by burlesona »

The article is really interesting, but the stress the author expresses about the potential downfall of NASA seems misplaced. This is just creative destruction at work. If NASA can adapt to capitalize on the new paradigm, then it will, and there will be NASA logos everywhere in future space stuff. If not, then NASA will fade away, and some of us will wax nostalgic about how cool NASA seemed when we were kids but nobody will really care because humanity will have moved far past the limited space exploration that was possible to-date.

Like most old US government programs, NASA is fully of wasteful political constraints - for instance, facilities scattered around the country and to satisfy pork-barrel politics and get random senators to support the overall program. I think NASA is still a net good, and I'd love to see it adapt, but if it fails to adapt, that probably just means the institutional dysfunction between Congress and NASA administration was too great, and even though it will be a little sad, it will still be a net win for humanity to replace that dysfunction with a new wave of highly functional new players.

Re: Starship is still not understood

#182

Post by qayxc »

gremloni wrote: post #98
qayxc wrote: post #78

Earlier quoted context omitted.

Even 90,000 launches over 10 launch windows is 9,000 launches per window. Launch opportunities are about 30 days max per window (depending on the flight profile) so that'd be 300 launches per day or over 12 launches per hour . I'm not saying this is bonkers, but this is completely ridiculous and it doesn't matter whether it's 90,000 or 180,000 or even "just" 45,000 launches - it's completely impractical. Not to menti…

Based on what, your gut feel? 12 launches per hour does not seem insane at all.

> Based on what, your gut feel?

Based on the fact that every orbital launch requires airspace restrictions, local road closures, blocked patches of sea and launch permissions.

The regulatory framework alone is incapable of dealing with that (keep in mind that every orbital rocket is basically an ICBM), let alone the fact that you'd have to spread launches over multiple sites therefore rendering considerable patches of air- and waterways completely closed up for weeks on end.

And that's just the regulatory side of things. There's also the logistical side wherein you'd have to consider methane production and -storage as well as ground operations.

100t-class orbital rockets aren't aeroplanes and the procedures involved in checking, refuelling and launch are much more involved. Keep in mind that SpaceX of all companies was the first company who managed to lose a rocket during fuelling in over 5 decades.

Now scale that risk (of currently 1:129 - make that 1:1000 since I'm being generous here) to 9,000 launches and you'd be looking at about 9 major explosions (worst case) per launch campaign and that's without the added stress from an unprecedented launch cadence taken into account.

You'd be looking at this: https://youtu.be/AOFVuAmcoCA?t=43

two times a week and handwaving that away by quoting fantasy goals for the achievable reliability isn't going to change the fact that even one such incident would halt the entire program for a considerable amount of time.

Re: Starship is still not understood

#183

Post by meepmorp »

vanattab wrote: post #123
gremloni wrote: post #98

Earlier quoted context omitted.

Based on what, your gut feel? 12 launches per hour does not seem insane at all.

In 2020 there was 114 orbital launches supporting all space missions around the world. That's 0.013 launches per hour. 12 launches per hour to support a single mission does not seem at least a little insane? I love SpaceX and am hopeful for their Mars plans but we are scientists and engineers let's think with our brains and not our hearts.

What's a few orders of magnitude among friends?

Re: Starship is still not understood

#184

Post by panick21_ »

vanattab wrote: post #175
panick21_ wrote: post #53

Earlier quoted context omitted.

> without Musk's unaccountable aura of burrocratic avoidance. In my opinion. Can you tell me exactly what you mean and how it significantly increased their development speed and overall performance? And can you show that different standards were applied to other space companies. They did one test launch where the FAA inspector wasn't there. This causes a review of the company by FAA and eventually they were allowed t…

>They did one test launch where the FAA inspector wasn't there. You are being deliberately misleading with this statement. You say that as if SpaceX accidentally launched while the inspector was in the bathroom. When in reality the FAA explicitly told SpaceX not to launch BEFORE the launch. And that doing so would be a violation of their launch license. The fact that the FAA reviewed the situation and then allowed to…

> You are being deliberately misleading with this statement.

No, I wasn't. I simply stated he wasn't there, and he wasn't. I didn't imply anything beyond that he wasn't there.

> proves the parents point.

No it doesn't. People violate different things and are allowed to continue to operate. Virgin Orbit was just stopped from operating and had to go threw review.

Doing a review of company and its safety culture is standard procedure.

This is not a human launcher, those have far higher requirements.

Can you actually show that if it wasn't SpaceX, the company would have somehow been stopped from continuing?

Re: Starship is still not understood

#185

Post by cletus »

NASA is hamstrung by Congress here. Congress mandated the SLS program. It's not meant to be competitive with SpaceX. SLS is a jobs program for key districts, no more, no less. It's welfare for Boeing.

I don't know if NASA personnel cannot plan for or even discuss SpaceX. It's probably not that overt. The powers there probably just realize it'd be career suicide to do so.

I completely agree that reducing LEO payload costs (in $/kg) by 2 or even 3 orders of magnitude will be game-changing.

Personally I'd like to see a viable competitor to SpaceX here because competition is good and it drives innovation. But it isn't Boeing, ULA or even Blue Origin. I actually think Blue Origin is so culturally broken that you'd almost be better off starting from scratch.

Re: Starship is still not understood

#186

Post by lquist »

oxplot wrote: post #126
lquist wrote: post #90

What am I missing here? Why is spacex valuation 100bn if this is true? I would think it would be 1tn easily in this kind of capital abundant environment. Is the risk that high? Is the market size being overestimated?

I'm no financial guru, even enthusiast, but my impression is that your average investor is interested in very short term profit. If you listened to last Telsa's shareholder meeting, one of the top questions was whether Tesla was going to pay dividends! People expect a company that's ramping up faster than any other in the history, building largest factories left and right, to pay dividends to its share holders! I'm i…

Sure, but SpaceX trades on the private markets, not public. The minimum to get into SpaceX is $1m.

Re: Starship is still not understood

#187

Post by h2odragon »

s1artibartfast wrote: post #134
h2odragon wrote: post #54

Earlier quoted context omitted.

I'm trying to conceive a vacuum capable hydraulic cylinder. As someone who has used backhoes to dig in water then helped refurb the cylinders afterwards. I'm not seeing any happy possibilities, myself. I agree that it should be possible to make things work at cheaper prices than NASA, but that's still a long way from "easy" or "Commercial off the Shelf"

I'm curious in what ways a industrial cylinder wouldn't be vacuum capable. Pressure shouldn't be a concern. they operate at 5-10,000 PSI above the ambient environment, so an additional 14 PSI differential shouldn't matter. I'm guessing operating temperatures would be a big concern What failed in water?

Corrosion is a concern, all over but especially on the inner cylinder that has to seal. The seals are probably OK but they're important and redo them anyway when its open. The fluid will pick up some water and thats a whole hydraulic system flush, once you get "too much".

Then you've got bearings and grease ports and channels that not only don't necessarily like water; but you're not operating in clean water either and that compounds all the problems.

Noting almost total ignorance of the realities: I forsee vacuum hydraulics problems including keeping seals tight, the inevitable oil coating on cylinders boiling off and getting polymerized residue buildup. Double enclose all the actuators and have another seal system so you can have a moving thing poking out of a hull, as is done for boats, will probably be necessary... and that'll have its own problems at the actuation points i bet.

Re: Starship is still not understood

#188

Post by vidarh »

themaninthedark wrote: post #161
vidarh wrote: post #43

Earlier quoted context omitted.

Solving food and clean water is not a technology problem. It's a political choice. The money exists to solve those things not just for the US but worldwide. I'm very much in favour of political change to solve them, but I long ago resigned myself to accepting that there's very little benefit in individual action to try to counter them other than to feel good unless a majority is willing to commit to the necessary soc…

To add, solving world hunger is more than just give everyone food. The USA had been supplying cheap/food to countries but this started causing the farmers in those countries to stop growing food because they could not compete with the free food. So either the US is a monster because they are undercutting the local market or they are a monster because they are throwing away food when people are going hungry.

You're right, but that's "just" a political problem too in the sense that it's a matter of willingness to spend the money near those who need aid rather than near the giver. Reducing subsidies in developed countries and instead paying to upgrade farming in developing countries would be one way.

So sure, giving food away is not a perfect solution other than for short term crises, but it's still a problem that is entirely solvable if there was will to do so.

Re: Starship is still not understood

#189

Post by snowwrestler »

> We need a team of economists to rederive the relative elasticities of various design choices and boil them down to a new set of design heuristics for space system production oriented towards maximizing volume of production. Or, more generally, maximizing some robust utility function assuming saturation of Starship launch capacity.

This is not really what economists do. Elasticity is not something an economist can “derive” or predict in advance of market developments with any reliability. It can only be reliably observed.

That is the whole point of a free market. What is possible—changes in elasticity between factors—emerges from complex behavior. As it emerges, new efforts can compete to take advantage of it, thereby themselves creating new possibilities.

This is why people are not re-inventing everything around the Starship vision yet; because it hasn’t actually happened yet.

There are many projects and companies sitting on the garbage heap of history because of, basically, a branch prediction error. They guessed wrong on direction or timing. Even if Elon is right about Starship costs, but it takes significantly longer than expected to get there, that’s a huge risk to projects that set it today as a dependency.

Re: Starship is still not understood

#190

Post by bryanlarsen »

dr_orpheus wrote: post #162
ncallaway wrote: post #8

I’m kinda confused by the criticism of the industry and NASA not designing for Starship. The author argues that NASA doesn’t understand Tempe game changer that Starship is, but I don’t think that’s accurate. I think the risk to NASA of assuming the benefits of Starship before it’s proven are just too high. If NASA (or other industry players), assume Starship will deliver the benefits it promises, they to fundamentall…

I think part of the point that the author misses is that while designing a spacecraft for a Starship launch does remove a lot of the constraints there is not the infrastructure to take advantage of that (yet). There have been some preliminary studies on spacecraft that could take advantage of a Starship launch capability, but we currently can't transport a spacecraft that large over the road. It would most likely hav…

When your primary customer says that they will never man-rate your rocket, as NASA's administrator Bolden did, it's more surprising that they actually went on to finish Falcon Heavy than that it was late.
Post reply on HN