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whatever1 ◴[] No.44300677[source]
Question why is it so easy today to build reusable rockets? Is it because the onboard cpu speed of the chips can solve more granular control problems with low latency?
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kurthr ◴[] No.44300707[source]
Proof of concept. It's a lot easier to do something, if you know it can be done.
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PaulHoule ◴[] No.44300852[source]
Also psychology and politics kept people from following the easy path.

The Space Shuttle was wrong in so many ways, not least that it was a "pickup truck" as opposed to a dedicated manned vehicle (with appropriate safety features) or a dedicated cargo vehicle. Because they couldn't do unmanned tests they were stuck with the barely reusable thermal tiles and couldn't replace them with something easier to reuse (or safer!)

Attempts at second generation reusable vehicles failed because rather than "solving reuse" they were all about single-stage to orbit (SSTO) [2] and aerospike engines and exotic composite materials that burned up the money/complexity/risk/technology budgets.

There was a report that came out towards the end of the SDI [3] phase that pointed out the path that SpaceX followed with Dragon 9 where you could make rather ordinary rockets and reuse the first stage but expend the second because the first stage is most of the expense. They thought psychology and politics would preclude that and that people would be seduced by SSTO, aerospikes, composites, etc.

Funny though out of all the design studies NASA did for the Shuttle and for heavy lift vehicles inspired by the O'Neill colony idea, there was a sketch of a "fly back booster" based on the Saturn V that would have basically been "Super Heavy" that was considered in 1979 that, retrospectively, could have given us Starship by 1990 or so. But no, we were committed to the Space Shuttle because boy the Soviet Union was intimidated by our willingness and ability to spend on senseless boondoggles!

[1] The first few times the shuttle went up they were afraid the tiles would get damaged and something like the Columbia accident would happen, they made some minor changes to get them to stick better and stopped worrying, at least in public. It took 100 launches for a failure mode than affects 1% of launches to actually happen.

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

[3] https://en.wikipedia.org/wiki/Strategic_Defense_Initiative (which would have required much cheaper launch)

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EvanAnderson ◴[] No.44300965[source]
> The Space Shuttle was wrong in so many ways, not least that it was a "pickup truck" as opposed to a dedicated manned vehicle (with appropriate safety features) or a dedicated cargo vehicle.

I wonder what the STS system would have been like if the DoD's cross-range requirement hadn't been imposed.

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PaulHoule ◴[] No.44301019[source]
That too... And the whole boondoggle about launching from Vandenberg that never happened. That bit about it being "dual use" though helped in the "intimidate the Soviet Union" department.
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EvanAnderson ◴[] No.44301130[source]
I enjoy the theory that the Space Shuttle fulfilled its mission as an economic weapon w/ respect to Buran.
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1. PaulHoule ◴[] No.44301439[source]
Well it did, but if you look at health care or infrastructure you'll see that the U.S. can intimidate anybody except maybe the Chinese when it comes to spending money.