Originally Posted by
balsa model
So it does look like the solution works great. (And an impressive engineering team, knocking down problems one-at-a-time.)
But what is the problem again?
And I'm not trying to disparage this effort - only the marketing explanations look to me naive or dishonest.
To be more precise, this claim of better lift to orbit:
Carrying quite a bit of extra hardware so that you can fly obliquely through the atmosphere to save a small fraction of the oxidizer weight, then claiming that overcoming the thick atmosphere in this manner is an achievement, just does not quite add up.
As to London-to-Sydney: what will be the idea for redundancy here? One glitch in this pre-cooler and I imagine the consequences will be spectacular.
Again, not in the spirit of disparaging the actual science/engineering of this thing.
Oxygen is very heavy. That's the issue. Not carrying it (or carrying only the bit you need for the portion of your journey that is in space) makes a HUGE difference.
We fly around with jet engines instead of rocket engines and that's one of the obvious reasons why. So why can't a jet engine be used at Mach 5? Well, air has to be slowed down from supersonic since shockwaves cause problems with the compressor and doing that makes it very hot and then you can melt your engine. REL's approach works up to M5 so it might help fighters or drones or even missiles get from runway to M5 (or less) with one engine and then endure longer.
I'm not an expert. Perhaps this explains better:
https://aviation.stackexchange.com/q...y-slow-it-down