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"This thoroughbred airliner could fly from London to Sydney in 17 hours, three minutes and 45 seconds; compared to around 22 hours on a Boeing 747." This sounds wrong - the concorde's cruising speed was more than double that of a 747. Unless they're taking the refueling time into account (Concorde would need more refueling stops)
If the engine has no moving parts, how do you get a ramjet off the ground?
"This thoroughbred airliner could fly from London to Sydney in 17 hours, three minutes and 45 seconds; compared to around 22 hours on a Boeing 747." This sounds wrong - the concorde's cruising speed was more than double that of a 747. Unless they're taking the refueling time into account (Concorde would need more refueling stops)
That's apparently the record time it achieved, as a charter flight. I'm sure there were multiple stopovers built in, and another major factor is likely to have been speed restrictions when flying overland. On the grounds of comfort I'd have preferred the even longer journey in the 747...
The biggest challenge will the same thing that killed Concorde: finding customers to pay super prices for super speed.
The only known shape which produces no sonic boom (Busemann's Biplane) also produces no lift. There is a known shape called the Sears-Haack body which produces very little turbulence - basically it's like a very long pointed football. The best we have been able to do is make airplanes resemble that shape by having short stubby wings at the widest portion of the airflow body, with an elongated snout and tail. It does reduce turbulence to a degree, but again you are hurting your lift.
I think this may actually be an insoluble problem. You need to disturb the air to produce lift, i.e. create a low-pressure zone over the wing, and a high-pressure zone under the wing. My fear is that this is inextricably linked to sonic booms, as we just seem to be exploring various locations within a space defining the tradeoffs between lift and sonic booms.
We may be able to do it if we get the sonic boom low enough, but this gets back to the cost tradeoff. A rocket is certainly one possible solution within this space - a no-lift body that follows a ballistic trajectory could probably be constructed not to produce a sonic boom. However any solution on this end runs right back into the cost problem that you noted. Rockets need a lot more fuel and maintenance than a fixed-wing craft, and they're a lot less safe.
The biggest challenge will the same thing that killed Concorde: finding customers to pay super prices for super speed.
Bear in mind, with Concorde, that at least part of its downfall lay in the sharp rise in fuel prices in the early 1970s. Had that steep increase not taken place, but something more gradual, its commercial fate could have been quite different, even if it was never going to be any mass carrier.
How does water vapor last longer at 25km than at 33km? From 33km it has to pass through the lower altitude which would mean more time than vapor that started at 25.
Not sure which, or what particles there would be more of at 33km than 25km, but that's my immediate guess.
The SABRE engine appears to be coming along well, with one of the largest challenges - cooling the incoming air extremely rapidly - seemingly overcome.
"This thoroughbred airliner could fly from London to Sydney in 17 hours, three minutes and 45 seconds; compared to around 22 hours on a Boeing 747." This sounds wrong - the concorde's cruising speed was more than double that of a 747. Unless they're taking the refueling time into account (Concorde would need more refueling stops)
Also there were over land speed limits applied. Apparently while at BOS you could hear the boom as the JFK-LHR flights accellerated once far enough off the coast
Concorde record was 2.88 hours (2h 53 minutes).
Ratio = 1.83:1. Much higher than the confusing Sydney comparison (1.25:1) with its stopovers.
This article is somewhere between "needs significant copyediting" and "probably generated by a bot." It's almost unreadable.
> (caption) The Soviet Tu-144 was the only only airliner to take passengers faster than the speed of sound I would agree with your bot assessment.