[mikepurvis]

The thing that's different between Boring/Hyperloop and SpaceX is that SpaceX's entire business case is built on the cost benefit of landing and reusing a rocket, an idea for which the napkin math was obvious and in the end turned out to be extremely feasible but which legacy providers had been unwilling to even try.

Boring/Hyperloop don't have an idea like this. Boring's pitch is using conventional TBMs but making it cheaper by digging a smaller-diameter tunnel than the other guy. Does that meet the requirements? New subway systems are also reducing tunnel diameter by using LRVs instead of heavy rail cars... is there an actual innovation here?

Hyperloop is full of practicality issues, and addresses none of the real problems that are barriers to high speed mass transit projects today— specifically the fights over rights of way and station locations. The fact that it was initially pitched in 2013 as a system for moving around private automobiles should tell you a lot about how much understanding there is of the first principles of transportation— it wasn't until years later that this was acknowledged and corrected [1]. It would be like someone proposing an airline where each plane carries 10 cars instead of 400 passengers ("so convenient, you just drive right on board!")— it doesn't matter how fast the trains are, 840 passengers per hour for a Hyperloop would be a complete nonstarter when a normal subway does 40k/hr.

Maybe Boring/Hyperloop will end up pivoting into something worthwhile, but at the moment there is good reason for skepticism.

[1]: https://www.masstransitmag.com/technology/news/12402366/elon...

[imtringued]

> The thing that's different between Boring/Hyperloop and SpaceX is that SpaceX's entire business case is built on the cost benefit of landing and reusing a rocket, an idea for which the napkin math was obvious and in the end turned out to be extremely feasible but which legacy providers had been unwilling to even try.

The cost of reusing a rocket has not been proven to be cheaper than building a new rocket. Consider factors like the inability to reuse the entire rocket, the reduced payload. At best you can break even. Unless you somehow reuse the entire rocket and do 100 flights with the same rocket the savings are meager.

This isn't something new. The space shuttle suffered from the same issues. Building new shuttles was almost the same cost and less risky.

[mikepurvis]

I think it's pretty obvious that the current gen F9s are way more reusable and with way less refurbishment than the Shuttle ever was, even with the disposable second stage. But yeah, there are limitations, which is part of why FH is effectively cancelled in favour of just flying those payloads on a disposable booster.

But now that the basic principle has been proven, really leaning into it is part of the point of Starship— a new clean sheet design that is built for full reusability from the get go.