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Japan's Supersonic Aircraft

by Astronuc
Tags: aircraft, japan, supersonic
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Danger
#19
May12-06, 02:59 PM
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Quote Quote by russ_watters
you could use retractable rocket combustion chambers inside the scramjet
You've gotta give them points for imagination. It looks good on the surface (to an amateur), but I'm guessing that you've got Fred's brain scratching itself.
Seems to me that it would be easier to put retractible engines elsewhere on the plane.
Astronuc
#20
May12-06, 09:18 PM
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CONCORDE'S SUCCESSOR

With Dreams of Super-Sonic Jets Dancing in Their Heads

Five years after the crash of a Concorde in Paris, French and Japanese researchers are planning the next generation of super-sonic civilian jets. But without a huge leap forward in technology, their plans may never take flight.

http://service.spiegel.de/cache/inte...363823,00.html
FredGarvin
#21
May13-06, 03:20 PM
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And in fact, the Concorde's successor is supposed to set new standards in these areas. The Japanese have announced that they have an engine that will be powerful enough to propel the new jet through the skies at a speed five times the speed of sound.
This sounds like another load of BS that a business person is spouting without knowing the technicalities of what they are saying. Let's just for a moment say that they had engines that could reach those speeds which are of the air breathing family and they can carry enough fuel to do go the distances they need. The one thing at M4+ that anyone MUST deal with is thermal managment. The thermal loads on the aircraft systems are phenomenal. I don't mean a little hurdle to overcome, I mean HUGE problems. I'd like to know how they intend to keep the fuel in the tanks from vaporizing. I'd like to know what fuel they plan on using because JET-A ain't gonna cut it. I'd like to know how they plan on keeping all of the people cooled to the point that is comfortable...
FredGarvin
#22
May13-06, 03:21 PM
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Quote Quote by russ_watters
Sounds reasonable to me. It looks like the temperature (and therefore speed of sound) decreases up to about 10km, holds steady, then starts increasing again at 20km: http://perso.wanadoo.fr/ballonsolaire/en-theorie2.htm

Oh - here's the speed of sound itself vs alt: http://www.aerospaceweb.org/question...re/q0112.shtml
The thing that causes the effect at other altitudes is a temperature inversion which do happen quite frequently.
Cliff_J
#23
May21-06, 06:47 PM
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Guess: Maybe the 1% just refers to a 20db reduction in noise put in laymans terms?

(manufacturer to journalist)
M: THIS ENGINE IS WHISPER QUIET AT ONLY 135dBA.
J: WHAT?
M: QUIET!
J: WHAT?
M: YEAH.
J: ???? (scribling notes)


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