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France and Japan Planning New Supersonic Jet
jonerik writes "According to this article from the Associated Press, Japan and France are cooperating on research to produce a supersonic passenger plane that would be able to carry 300 passengers (three times as many as the Concorde) and fly from New York City to Tokyo in a mere six hours. Current plans are for the plane to be able to cruise at mach 2.4 while reducing the noise and high fuel consumption associated with the Concorde during its years of service. Although Japan had previously done extensive research towards building a 250-person mach 1.6 passenger jet, the agreement with France - announced at the annual Paris Air Show on Tuesday - represents a interesting shift in technological alliances given the Japanese aviation industry's longstanding ties to the United States. 'To research closely in this area with the Europeans does represent something new,' said Yoshio Watanabe, an official with The Society of Japanese Aerospace Companies, which is heading the new initiative on the Japanese side."
represents a interesting shift in technological alliances given the Japanese aviation industry's longstanding ties to the United States
Does it really or are they just trying to benefit from France's experiences with the concorde for this project?
Nowhere in the article does it say it'll change it's alliance for anything else.
Sig? What's this sig thing I hear people talking about?
Bing Bing Bing! We have a wrong answer!
Sonic boom is tottaly due to pressure waves created by going faster than the speed of sound.
http://en.wikipedia.org/wiki/Sonic_boom
Here is the flight path from New York to Tokyo:
http://gc.kls2.com/cgi-bin/gcmap?PATH=jfk-tyo
The article's not refering to the sonic boom (usually happens above the ocean anyway), but to the actual engine noise.
The concorde had the loudest engine around, and I think it was a problem for most airport noise regulation.
Except that 3 is irrelevant, for the fact that the flight path looks like this: http://gc.kls2.com/cgi-bin/gcmap?PATH=jfk-tyo (thanks to an earlier poster).
Looks like it goes right through Canada, quite a bit of America, and China(?)
-WolfWithoutAClause
"Gravity is only a theory, not a fact!"Supersonic jets in the past used real jets, not turbofans, afterburners if you like. Basically just burning raw jet fuel and using the hot gas to accelerate the plane. Fast, but VERY inefficient. Normal jets get theri efficiency from their turbofan engines.
Now these days It is possible in theory. The FA-22 has engines that can go supersonic on turbofan, but I don't know that they'd pull Mach 2 (I dunno how fast they can go on TF before they need to go burner). Also just because they can make a small fighter do it does not mean they can make a large passenger jet.
If the jet is a real jet engine it'll be fairly noisy and not very efficient as compared to the new Boeing and Airbus offerings.
So it really depends on what kind of implementation they can get. If they make a jet that's all turbofan, and can do efficient subsonic flight then ya, might be a winner. If it's just a new Concorde I'mm betting costs will be prohibitive, and noise a major problem.
Completely wrong. What event horizon?
Shockwaves are caused by an object moving through a fluid faster than the speed of sound (ie: the speed of pressure wave propagation in the fluid). At subsonic speeds, pressure waves bouncing back from an object affect the incoming flow, basically "warning" it of the existance of the object. That's how the fluid can flow smoothly around the object --- the pressure waves caused the fluid's path to change long before it hit the object. At supersonic velocities, the pressure waves don't move fast enough to affect the incoming flow. So the fluid cannot flow smoothly around the object, and a shock wave is created where the fluid has to instantaneously react to the presence of the object.
A deep unwavering belief is a sure sign you're missing something...
SST's get re-studied every decade or so. Boeing and Douglas (remember them) last took their turn in the 80's, courtesy NASA funds. Gulfstream and one of the Russian design houses got far down the road toward a supersonic bizjet in the 90s. Now it is Japan's turn. They all run into the same laws of physics, and the same laws of economics. Until there's a breakthrough in engines, structures, fuels, or aerodynamics (or perhaps all four), don't look for an SST anytime in the next decade or two. An SST could be built today, even without breakthroughs, but it wouldn't make anybody any money. The laws of physics guarantee that the planes are exotic (skin temperature hot enough to boil water), thirsty (inefficient supersonic wing lift), and noisy (sonic boom = flight routes over land very restricted). These factors all add up to expensive tickets, and the market studies (including the one called Concorde) all show that the market isn't there. And that's not even beginning to take environmental concerns into account, such as high-altitude ozone depletion and of course greenhouse gas emissions.
I hope the project is successful, however, if it doesn't get buy-in from the beginning it could suffer the same fate as Concorde. Although Concorde was a technical marvel, the U.S. did everything it could to scuttle the project, for example, its flight certificate was delayed by the FAA until it was sure the project was busted. The premise of Concorde was fast trans-atlantic flight, but its first scheduled route was Heathrow to Bahrain because countries followed the U.S. and refused flight certificates. By the time the U.S. did grant a heavily restricted certification the lack of orders had made continued manufacture untenable. It's quite ironic that the U.S. refused certification on environmental grounds.
t
I'm sure there will be the usual Concorde counter-arguments posted here, some of them are true. It's true that it was a fuel hog and it's true that it was noisy. But if 500 were built instead of just 16 supersonic flight would have become much cheaper. With only 16 all parts were custom built and very expensive. Heck the Concorde has more in common with the SR-71 than a 737. It boggles the mind to think that it cruised faster than an F-18's top speed.
My father worked on the project from the beginning, for those interested here's a link to a couple of photos he took when Concorde 002 made its maiden flight-
http://latte.com/gallery/Concorde-002-First-Fligh