Japan and Europe are cooperating on a pre-cooled turbojet.
Unfortunately, they seem to be ignoring the real issue, which is drag and fuel consumption. I think that Mach 5 is above the sweet spot for a practical system.
6 thoughts on “Hypersonics”
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Should we read anything into the fact that SABRE and Scimitar aren’t mentioned in any of this? I notice that the ESA is involved in this project through LAPCAT II. Scimitar was a big part of LAPCAT I, wasn’t it? Did REL get thrown out for some reason?
The SABRE idea has similarities but the implementation is very different.
The SABRE intake has a circular cross-section which can be closed into a cone at low atmospheric pressure, with an onboard Oxygen supply to maintain combustion all the way to orbit. The precooler for the SABRE is directly inline immediately after the intake, followed by the compressor.
The Japanese engine has a rectangular thrust tube intake, and the precooler follows a 70 degree or so bend in the airflow, followed by the reverse bend, and then it looks like some of the compressed air is siphoned off from the main flow to run a turbine that pumps LH2 through the precooler and then into the combustion chamber. Mach 5 maybe, orbit hell no.
Well, Hikari has WP3, which does mentions Range, Capacity, Operating Cost and so on. Drag and fuel consumption would be necessary parts of any analyses.
I do wonder about ETOPS and the end of trip 30 minute loiter requirements – there isn’t much in the way of old fashioned wings on most hypersonic designs.
Well sure but they need to start with something. Getting the propulsion to work would be a significant step.
Yeah Mach 5 is pushing it. I mean there are no supersonic transporters left and todays military aircraft don’t go much faster than Mach 2. We know Mach 3 is doable. The SR-71 did it.
Even a Mach 1.8 transport would be an improvement and that can probably be done without afterburners since the F-22 can do that in supercruise.
I just remembered the ADVENT engine:
http://en.wikipedia.org/wiki/Adaptive_Versatile_Engine_Technology
Well sure but they need to start with something. Getting the propulsion to work would be a significant step.
Propulsion is not the problem. We know how to make things move that fast — it’s called rockets. Drag is the problem. And that includes wave drag.
Compression lift! Wave rider! Sanger “skip bomber”! Dynamic soaring!
Av Week at an article about some proposal for a rocket-boosted intercontinental transport that would get favorable fuel economy by doing a series of hypersonic partial reentries (skips) followed by exo-atmospheric parabolas.
Fogetabout the thermal demands that probably round-filed prior proposals for this mode of travel. Can you say “air-sickness bag”? I knew you could!