The challenges of building a hypersonic airliner
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Re: The challenges of building a hypersonic airliner
#2"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)
Re: The challenges of building a hypersonic airliner
#3"the heat that accumulated at Mach 8 was up to 30% less than at Mach 5."
while the original paper says
"Actually the thermal flux during Mach 8 flight is shown to be only 25 to 35% higher than at Mach 5. On top of this, the reduced flight times at Mach 8 yields a 20 to 25% reduction of the overall integrated heat load to the fuselage with respect to the Mach 5 cruise."
The combined effect seems to be that the shorter the flight (& faster), the lower the impact of the heating for people inside.
Re: The challenges of building a hypersonic airliner
#4This article is somewhere between "needs significant copyediting" and "probably generated by a bot." It's almost unreadable.
Re: The challenges of building a hypersonic airliner
#5If the engine has no moving parts, how do you get a ramjet off the ground?
Re: The challenges of building a hypersonic airliner
#6"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)
From what I've been able to find the route was a one-off chartered flight in February, 1985[1]. There were a few delays and because they were attempting for a world-record time, a bit longer because certain conditions had to be met.
[1] https://news.google.com/newspapers?nid=1301&dat=19850215&id=...
Re: The challenges of building a hypersonic airliner
#7"the heat that accumulated at Mach 8 was up to 30% less than at Mach 5." while the original paper says "Actually the thermal flux during Mach 8 flight is shown to be only 25 to 35% higher than at Mach 5. On top of this, the reduced flight times at Mach 8 yields a 20 to 25% reduction of the overall integrated heat load to the fuselage with respect to the Mach 5 cruise." The combined effect seems to be that the shorter…
Active cooling: If you put the extra heat into fuel, you have a higher fuel flow per second at the faster speed so you can indeed cope with the higher heat flux and enjoy the lower total heat quantity.
Passive cooling: If you have to radiate the heat away , then the surfaces will reach a steady state relatively quickly and you have to deal with the flux. If you burn up in two minutes it doesn't help you that the flight would only last two hours. You can't carry heavy heat sinks in an aircraft.
Re: The challenges of building a hypersonic airliner
#8"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...
Re: The challenges of building a hypersonic airliner
#9The biggest challenge will the same thing that killed Concorde: finding customers to pay super prices for super speed.
Re: The challenges of building a hypersonic airliner
#10This 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.