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by avmich 1044 days ago
> The whole point of these two adages is that reusing an existing design is better than a new one.

Yes, and that's put in doubt. Starship aims to improve on previous designs - in terms of affordability, that is, making human flights cheaper. This cheapness can't be realized with existing designs, so a new design becomes better in that regard.

> SpaceX's REUSABLE rockets are great for a number of reasons yes, but by definition, those are not NEW launch vehicles.

I don't know how good definition can exclude reusable rockets from being new. Was Shuttle ever new? Delta Clipper? Reusable Falcon-9? Falcon Heavy? I think this is not a good definition, if, according to it, reusable rockets can't be new.

> And when they were new, well, lots of delays and setbacks and costs as they kept accidentallying rockets trying to land them.

Do you know the difference between designing and using? In software it's rather clear, and nobody would expect a half-written program to function according to specs. Neither it's the case in aerospace - while Falcon reusability was being designed and tested, nobody should expect it to perform flawlessly as when used "in production". Not cheap, agree (actually, quite cheap by aerospace standards, but still not some typical household-sized money), but I'd argue that was rather quick - just a few years to put reusable first stage into production starting from announcing the idea and building the first "Grasshopper". So, while 39[a] may stand here, your comment doesn't provide a good justification to it.

> If anything, SpaceX's entire business model is EMBRACING that adage, not disproving it or an exception to it.

SpaceX benefited immensely from using proven solutions, but the results they are showing are still disproving the idea of this law. The ambitions of SpaceX are high compared to the rest of the world launching industry, but so are the results, and we also have genuine "firsts", like putting the reusable first stage into production, or flying reusable spacecrafts to space station, TKSes and Shuttles notwithstanding.

Let me try to explain again my main point: SpaceX aims to make human spaceflight significantly cheaper, and the opinion is that it can't be done without radical redesign from scratch. It was attempted several times in the past, with e.g. Shuttle and Energiya, and it still isn't done today, but if you want to risk being put on the "you're currently here" list of SpaceX achievements(1), which were doubted and then happened, I'd at least propose you to think from the basic assumptions and find out why SpaceX won't actually achieve cheaper human spaceflight this time.

(1) In Russian that list looked like this before reusable Falcon: https://meduza.io/impro/0ZWeCgCXA4nsWv7dj7CHbSIrsURgOh-qpiUh...

4 comments

None of this is put in doubt though. Your points about SpaceX's potential for future cost savings and efficiencies are hardly realized today - particularly when considering the length of time that has been spent without a capable manned vehicle. If, fast forward a decade or two and SpaceX is still using today's designs (albeit, upgraded) and actually realized massive savings - then we can talk. However, I'd bet they're going to re-design and build brand new models along the way...

There's a reason military aircraft tend to have extreme service lives. It's far cheaper and effective to upgrade and refit/improve existing airframes with modern technology than it is to start from scratch - every single time.

Look at the F-35 program. It's not exactly fair because the design goals are vastly different - but upgrading aging F-15's has kept them on the battlefield for 47 years[1], and today they're still a seriously potent air superiority fighter. The F-15's of today are only similar in shape to the originals, however.

[1] https://en.wikipedia.org/wiki/McDonnell_Douglas_F-15_Eagle

> There's a reason military aircraft tend to have extreme service lives.

Only during peacetime. During war (hot or cold) they often have a rather short service life before becoming obsolete.

The “No new launch vehicles” adage reads to me as “Don’t develop a new browser when you make a website”

That doesn’t mean we never need or want a new browser. It just means that developing a browser is a separate project and if your fancy websites requires a new browser, it is in fact a browser development project, not a website project.

I take it as similar to the “never do a massive rewrite” rule for coding. It’s not that it never should be done, it’s that it shouldn’t ever be assumed to be “the easy part”.
> I don't know how good definition can exclude reusable rockets from being new

Because you're hung up on trying to tell me that the concept of reusable rockets is new in a grand history since while I'm trying to convey to you that the original Falcon 9 reusable rockets development ended over a decade ago.

> Do you know the difference between designing and using

You're the one struggling with that concept and the semantics around it, because you yet again prove my point while trying to argue it.

> SpaceX benefited immensely from using proven solutions

I'm glad you agree with the core point of my idea. Weird that you're so combative about it.

> Let me try to explain again my main point:

Don't bother, you missed the point of my comment entirely. Have a nice day.

No understanding :) .
> In software it's rather clear

In software, I perceive there to be almost no separation whatsoever between design and use. I’m using windows 11 right now, and sometime in the next few days it will silently download software patches that were designed over the last few days to address situations not considered in the original design of windows 11. Software goes back and forth from the design process to active use pretty much continuously these days.

Just an alternate perspective to think about.

I don't think that's the case, or all of the case.

Windows might download patches and update components but the core OS design, is there for over 15 or more years, and ditto for most of the userland, when it doesn't go back to Windows NT times..

I completely agree with you insofaras parts of the design probably go back to NT. SBut some of the design won’t happen until next week. My interpretation of this is that the design process starts before use and continues until the end of the support lifecycle. I agree that there are some components that we think have been completely designed… but there might be a bug tomorrow in a “core” part of the OS that would require more design, and I don’t think this would surprise anyone if it happened.

I’m not saying necessarily that it’s continuous design, simply that we might return to the design phase at any time.