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Comment by Sharlin | Hacker News Reader

Heard about the Space Shuttle? Or the SpaceX Falcon 9?

The reason it hasn’t been done in scale before SpaceX is that reusability is a hard problem to solve and it is/was more economical to use expendable launch vehicles than to develop recoverable and refurbishable stages.

You might also like to read about single-stage-to-orbit (SSTO) which is something of a pipe dream. The rocket equation is a bitch.

https://en.wikipedia.org/wiki/Single-stage-to-orbit

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The shuttle was a re-usable ship, the rockets used to get it into space were not reusable.

That’s not true… both the RS-25 SSMEs and the SRBs were reused - however, the extent of refurbishment required between flights was so extensive, time-consuming and expensive, that it erased much of the benefits of reusability

Not so. The solid rocket boosters were reused, as were the three SSMEs bolted to the orbiter itself. The only part that wasn’t reusable was the external fuel tank because bringing it back intact from almost orbital speeds would’ve been hilariously uneconomical.

That said, refurbishing both the SRBs and the SSMEs after each use was labor-intensive and as such expensive.

The SRBs were collected from the sea for reused and the upper stage was reused after landing horizontally. The only thing not reused was the upper stage drop tank. That single use drop tank was rather big, true, but not a rocket, not a rocket at all.

The Soviet lookalike did use a single use rocket as its second stage, with the reusable part just being an orbiter.

Interestingly, the Buran’s Energyia launch vehicle could possibly have been made reusable exactly because the tank and the engines were one unit. At the expense of payload capacity, of course. And anyway the Soviets were confused about the whole shuttle concept because it didn't seem to make economical sense, reusable booster or not – but they assumed the Americans knew something they didn't.

How would Energyia become reusable? Tail landing? Is there more to this, something specific that would make Energyia a candidate for tail landing other than just "if F9 can do it, in theory every liquid fueled rocket could do it"?

all the concepts i've seen were horizontal landing mostly with fold-out wings

Wow, that's ... ambitious. I'd imagine the extra mass to make an energyia-size tank+engines able to land horizontally to be enormous. It's not just wings (plus folding mechanism, if you believe that's worth saving a bit of drag on the way up) but also landing gear plus all the structural strengthening required.

Sounds suspiciously like one of those projects you propose when you want something finer short term but assume that they never survive to the point where they actually need to deliver?

Ah, no, I was mostly just idly speculating that at least it could've been possible in principle, but there in fact were some (possibly unrealistic) plans to make it fully reusable, see https://en.wikipedia.org/wiki/Energia_(rocket)#Energia-2_(GK...

"Refurbishable" would be a better term than "reusable".

Refurbishment of the shuttle orbiter took months and tens of thousands of work hours before it could fly again. It was pretty far from what ordinary people understand under "reuse", though not completely outside the meaning of the word.

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