The Briefing Room
General Category => Science, Technology and Knowledge => Topic started by: endicom on August 12, 2018, 12:04:32 am
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Flight Global
Stephen Trimble
Aug. 10, 2018
Hypersonic passenger travel still seems more like dreamy work of science fiction than a feasible commercial project, but this is now a fact: Boeing is working on it, and it’s a serious project.
“It may not be as hard as people think it is,†says Boeing chief technology officer Greg Hyslop, who quickly adds a caveat: “It’s still going to be hard.â€
Boeing first unveiled its hypersonic airliner concept on 26 June at an aviation technology conference and highlighted it again at the Farnborough air show in July.
In an industry that has lacked a supersonic transport option since 2003, suddenly proposing a hypersonic airliner as a viable option within 20-30 years seems to register somewhere between the ambitious and the absurd.
More... https://www.flightglobal.com/news/articles/hypersonic-airliner-may-not-be-as-hard-as-people-th-451069/ (https://www.flightglobal.com/news/articles/hypersonic-airliner-may-not-be-as-hard-as-people-th-451069/)
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Great article...
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Not economically feasible for most pasengers.
My brother-in-law commuted from NYC to London on the Concorde on his employer's dime (major record company senior exec), but that doesn't mean most passengers would use it even for typical air travel.
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I remember when I was flying all the time, probably 15 years ago, and they slowed the flights down by about 10% to save money on fuel.
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Not economically feasible for most pasengers.
My brother-in-law commuted from NYC to London on the Concorde on his employer's dime (major record company senior exec), but that doesn't mean most passengers would use it even for typical air travel.
Yep. Supersonic drag makes it a fuel hog. Hypersonic will be even worse. Faster than sound travel will always be very expensive. Physics cannot be denied despite wishful thinking.
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I remember when I was flying all the time, probably 15 years ago, and they slowed the flights down by about 10% to save money on fuel.
Most airliners cruise at about 475-500 mph. That seems to be the most economical speed
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Yep. Supersonic drag makes it a fuel hog. Hypersonic will be even worse. Faster than sound travel will always be very expensive. Physics cannot be denied despite wishful thinking.
Exactly!
You gotta push those molecules out of the way somehow!
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Exactly!
You gotta push those molecules out of the way somehow!
There are fewer molecules at 90,000 feet.
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There are fewer molecules at 90,000 feet.
True. But a Mach 5, you hit the ones that are there pretty hard and fast.
Which generates more heat on the skin surface? Airliner at @ 30,000 ft and 560 mph or this @ 90,000 and 3,800 mph?
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True. But a Mach 5, you hit the ones that are there pretty hard and fast.
Which generates more heat on the skin surface? Airliner at @ 30,000 ft and 560 mph or this @ 90,000 and 3,800 mph?
I wonder if air could be injected into the atmosphere to provide a slip surface with low friction like supercavitation with a torpedo?
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I wonder if air could be injected into the atmosphere to provide a slip surface with low friction like supercavitation with a torpedo?
Sourced from where?
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True. But a Mach 5, you hit the ones that are there pretty hard and fast.
Which generates more heat on the skin surface? Airliner at @ 30,000 ft and 560 mph or this @ 90,000 and 3,800 mph?
The latter, as evidence I give you the SR-71 and X-15. Both of those flew very fast at 90,000+ ft and got very hot.
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I wonder if air could be injected into the atmosphere to provide a slip surface with low friction like supercavitation with a torpedo?
It is still air and will generate the exact amount of drag. To avoid friction from the air, you have to get very high, like 50+ miles up, and there you have to use a rocket since there is no air to run a jet engine.