SpaceX's most-flown reusable rocket will go for its 20th launch tonight | Hacker News Reader

SpaceX's most-flown reusable rocket will go for its 20th launch tonight

arstechnica.com

76 pointsrbanffy42 comments

It's worth noting that when George Sowers and ULA did their well-known business case analysis for re-use (nearly 10 years ago, in 2015), their analysis concluded that it would take 10 flights to pay-off the penalty of re-use.

The analysis was flawed from the start, because it falsely assumed you could charge for every kg of capacity, but in reality customers are largely paying by flight, and much of the Falcon 9 capacity is unused.

But even according to their flawed analysis, they assumed there would never be a need for so many flights, and re-use would just eat into their production line productivity, raising the cost of each rocket.

These false assumptions caused them not to pursue any real type of reusabilty. Though they proposed a janky system where the engines would be recovered by parachute and helicopter, they never funded it, and the current Vulcan doesn't support any type of reuse.

Flash forward to today, and ULA has a contract for possibly 83 launches from Amazon for Kuiper.

What a terrible lack of foresight.

SpaceX’s propulsive recovery testing began over ten years ago, meaning a development campaign starting today would be ten years behind SpaceX if they can progress at the same speed. It seems crazy to me that essentially no one is even trying to follow the path demonstrated by SpaceX.

https://www.relativityspace.com/terran-r

It's true that Relativity Space Terran-R, Rocket Lab Neutron, and Blue Origin New Glenn are under development and are planning first stage re-use although none have flown. And also Stoke Space is developing a 2nd stage re-use solution which SpaceX hasn't solved yet. I think another American company could have a Falcon 9 competitor within 5 years if they really move fast. But they haven't yet reached the stage that SpaceX reached 10 years ago.

> ULA has a contract for possibly 83 launches from Amazon for Kuiper.

To put that into perspective, a single SpaceX booster could cover 25% of those launches!

It seems the problem in the ULA analysis is that it assumes that the cost of the reusable parts, saved by reuse, is only 30% of the total launch cost.

But Falcon 9 seems to cost $40-60 million and carries 200 tons of RP-1 which seems to cost $200-500k, and all other costs should either be small or removable by automation, so the reusable part is actually up to 98-99%, not 30%.

Of course if you just flush boatloads of money down the drain for each launch for no reason, reusing the booster doesn't change much.

Also in general that sort of mathematical modelling is usually worse than useless since the output is usually a straightforward function of the assumptions and the model just makes bullshit assumptions seem more legitimate.

> the reusable part is actually up to 98-99%

Reminder: they still throw away the second stage, but they do retrieve some of the fairings. It's high, but not that high.

Exactly—getting it that high is one of the primary objectives of the Starship initiative.

>But even according to their flawed analysis, they assumed there would never be a need for so many flights

This is an example of Musk's tech background in action. He knew from his career that if you sell something useful for a very low price, uses for it appear that hadn't existed before. SpaceX's hardware development method of blowing rockets up until one works is basically a edit-compile-run debug cycle.

>and re-use would just eat into their production line productivity, raising the cost of each rocket.

Arianespace specifically and infamously said that reusability would be bad because it would leave rocket assembly crews with nothing to do. I wouldn't be surprised if ULA had the same issue in mind, but at least no one there was dumb enough to publicly say so.

It’s remarkable what SpaceX is accomplishing in terms of making access to space routine. I did not realize how much progress they’ve been making over the last few years.

They've got 24/7 ops and building of Starbase in Boca Chica and KSC going on as well as loads of other sites, it's quite something. Checkout LabPadre and NASA Space Flight (NSF) on Youtube, tank watching is quite fun.

Going from expendable to reusable rockets will be a transition similar to the transition from silent movies to sound movies.

Many of the old stars of the field won't survive the change.

That's a creative comparison I would never have come up with.

Boeing has been beaten up here for their planes, rightly so, but that mess has made itself know with Starliner as well. Since it hasn't killed anyone or gotten off the ground with people at all, it's pretty much a joke. Any time I hear of another delay, my response is "of course it is". At least they are not forcing the issues and putting astronaut lives on the line. About the only good thing I can say about that program

> Boeing has been beaten up here for their planes, rightly so, but that mess has made itself know with Starliner as well.

And the Air Force One contract, and the KC-46 contract, and...

Last I checked, those were all planes

Another way of viewing it is that Boeing is messing up both their routine business and the special projects that they could/should be giving particular attention too, putting their elite talent on those jobs, etc.

>At least they are not forcing the issues and putting astronaut lives on the line.

Which "they" do you think is driving this choice? NASA or Boeing? I suspect it's the former, so I don't know how much credit should go to Boeing.

If Starship succeeds, the window of opportunity for small launch providers might be closed since there is no way they could compete. Commercial launch providers without a similar capability could all be pushed out of business. For any new company to challenge SpaceX would basically be impossible. Old companies with deep wallets might still be in the running.

The US govt will force into existence a competitor OR keep one of the old ones around on life support. They have made their position clear and have been backing it up with money.

All governments probably want their own space program, but only some can afford it. Those that can all force into existence a local space program because they need to be able to launch their own stuff for national security and defence purposes.

Countries with their own space program: EU, India, China, Russia, etc. None of them are cheaper than Falcon 9 and none of them will be able to compete with Starship anytime soon, but they will all continue to exist even if Starship becomes a runaway success.

I worry that corporations have gotten better at the art of siphoning money from such programs without delivering on the intent, making more money from repeated failures. I worry that there is no longer the political ability to punish big companies for their failures. At such of a point it becomes impossible to will such projects into existence. I wonder if China, in essence, has more of an ability to punish corporations due to the power concentration at the top and if this paradoxically allows for better competition between corporations that are less powerful than the politicians. Perhaps at a certain point of corruption the leadership in effect already owns everything so the agency costs from such corruption is greatly reduced.

That's a separate concern, but it's definitely a concern.

I agree China could potentially punish easier, but they can also bribe/allow grifting easier.

>The US govt will force into existence a competitor

Rocket Lab plus SpaceX having two proven launch vehicles (Starship and Falcon 9) might be sufficient to satisfy the US government's desire for alternatives. Rocket Lab is already launching national security payloads.

Agreed, but Rocket Lab hasn't quite gotten around to shipping larger cargo. I know it's on their TODO list, so I hope they manage to move it to their DONE list :)

It's a long shot but Relativity is keyed in to something most folks don't get or see. Using 3d printing heavily to radically unconstrain design & figure out where you want to put every ounce of material could be a huge advantage.

It might not be fast, but we have to compare the net cost, of letting printers run, versus figuring out exact manufacturing processes for thousands of parts netting millions of discrete operations.

These are costly works, but I'm actually less scared than I'd expect that this is an un-disruptable lead. We have much better control systems, much better manufacturing systems, and a clear example of what definitely works that creates a corporate necessity the old guard never & perhaps still doesn't understand.

I think that a smaller launch system that can launch from "anywhere" (a wide choice of launch pads), and can insert your moderate spacecraft directly to the orbit yo specify, not as a par of a huge multi-craft launch to a compromise intermediate orbit, may have a market. I suppose Electron [1] is targeting it, for instance.

[1]: https://en.wikipedia.org/wiki/Rocket_Lab_Electron

Generation-defining technology. Humanity is back, baby! Man, this guy is going to be immortal for the stuff he's done. He'll be remembered like Edison.

>like Edison

sensible chuckle

... Are they the same engines though?

Don't get me wrong, it's impressive that the pressure tanks can take that many cryogenic cycles, but I am not sure I would call it the same "rocket".

Does it matter if they are the same? If they have an inventory of engines that get rebuilt after launches but enough that they do not need to delay launches, it's good enough for my use.

It's similar to a NASCAR race. They pretty much tear those down and rebuild after each race as well, but it's the "same" car.

It matters and it doesn't. It doesn't affect turn around because you can have a ready to go inventory.

But it matters how much an engine can be reused because it's a significant material and labor effort to produce them. Are the 9 engines from each flight reusable, and to what extent? Does half the motor get replaced each time or is it generally ok?

The Ship of Theseus debate doesn't have a hard answer to it. We can -like the Persian Immortal - respect the continuity of the thing. But so too we should track and follow the churn of the pieces, acknowledge the parts decayed. I for one am very curious how much of the ship and how much of the motor needs replacement, and how often.

In the context of rockets, what is important and salient here is reuse, and even if some motors are swapped out, they are still available for refurbishment, rather than destroyed on reentry.

Unless they have to be written off cause they are wrecked?

Tesla's kept this one close to the chest. We really don't seem to have much data at all on how the rocket engines are doing after re-entry. The rocket engine itself might well be it's own Ship of Theseus, requiring considerable replacement. We just don't know, it's just not clear.

Would launches be as cheap if they had to keep replacing the most complicated part of the ship? Could they hide the expense of replacing the engines with subsidized pricing like Uber?

Ship of Theseus

The engines are the most expensive part of any rocket by far. Clearly SpaceX has produced some incredible economies from reuse, but it's definitely not as clear cut as simply "reusing a single rocket twenty times".

https://en.wikipedia.org/wiki/Ship_of_Theseus

Booster processing between launches sometimes takes as little as 7 days. That probably rules out any engine replacements at least on some launches.

They seem to be able to switch out a Raptor 2 in a couple of hours, even quicker sometimes. It's not impossible there will be some need for maintenance on the Merlins, probably on the injectors I'd imagine, as there'll be some coking build up (it's RP1 not CH4).

not as many as you would think. They don't do very many static fires of falcon 9 at all anymore.

https://aviationweek.com/defense-space/space/spacex-building...

"For example, the company changed its requirement to perform a static firing every time an engine was removed.

“Now we have to drop three engines before we go do a static fire because we determined we can put the high-pressure joints together, verify that they’re leak-tight and everything works,” Gerstenmaier says. “We’ve removed like 14 static fires out of the flow that would have been required under our old criteria, and all 14 of those flights launched on the first attempt.”"

Is there any source you can provide that says they have to swap the engines out?

> ... Are they the same engines though?

The answer is we don't know. SpaceX have not published much detailed information about exactly what they do during booster refurbishment, how much is simply inspected, how much is replaced and how much is "swapped out".

The fastest turnaround for a booster is 21 days (and plenty have been less than 30). [1]

[1] https://en.wikipedia.org/wiki/List_of_Falcon_9_and_Falcon_He...

It's possible to make rocket engines able to perform for quite a long time.

http://www.lpre.de/sntk/NK-33/tests.htm

В 1976 г. один из двигателей первой ступени НК-33 вместо 140 с, требуемых техническим заданием, проработал на стенде 14.000 с.

In 1976 one of NK-33 rocket engines instead of 140 seconds required by the specification run on the test stand for 14,000 seconds.

Reply on news.ycombinator.com