Via Clark Lindsey, here's one of those periodic stories that someone is working on a Concorde successor. As usual, it makes little technical or economic sense (at least the story, if not the reality).

It is full of contradictory statements, to anyone who understands basic aeronautics. Example:

Japan is trying to leapfrog ahead in the aerospace field with a plan to build a next-generation airliner that can fly between Tokyo and Los Angeles in about three hours. But a string of glitches, including a nose cone problem during the latest test flight in March, has led the Japan Aerospace Exploration Agency to look for an international partner.

“In the future, we think we need some kind of cooperation with NASA,” JAXA spokesman Kiyotaka Yashiro said. “Every developed country is doing some kind of research, the U.S., Europe and Russia. International cooperation is essential.”

This is just a tossed word salad. Three hours? Three hours isn't a Concorde successor--that's hypersonic. LA-Tokyo is about fifty-five hundred miles. Three hours means about 2000 mph (taking into account takeoff, landing, etc.). That's over Mach 3. That would be quite a leap, given that we haven't even figured out how to do Mach 2 affordably.

There is a "sweet spot" in aircraft speed that balances the costs of rising fuel consumption with speed, against the diminishing returns on higher speed, considering the time one spends getting to and from the airport. If one wants to have cost-effective supersonics, it doesn't make sense to choose a tougher goal of Mach 3 when an easier Mach 2.5 will still get one to Tokyo in four hours, a huge improvement over the current eleven.

And what do "nose cones" have to do with anything? It doesn't explain, but I'm not aware of nose cones (whatever they are) being a barrier to supersonic flight. And how does one leap to the conclusion that a "nose cone" problem is sufficiently insurmountable that it requires international cooperation in general, and help from NASA (which wasted over a billion dollars of taxpayer dollars on supersonic transport research in the nineties) in particular? Why would they think that NASA understands the problem, in the face of so much evidence to the contrary?

Yashiro’s comments came in response to a Japanese newspaper report that said JAXA would ally with NASA and the U.S.-based aerospace manufacturer Boeing Co. on the next stage of development. Japan is expected to develop the engine, which would generate 1 percent of the noise of the Concorde, while Boeing builds the airframe, the Nihon Keizai newspaper said.

Yashiro said the report was premature and that no decisions have been made on partners.

In other words, there's nothing to the story, which makes no sense. How does one have an engine that generates "1 percent of the noise of the Concorde"? And what evidence is there that Boeing knows how to build a cost-effective airframe for a supersonic transport?

Among the hurdles are two difficulties that plagued the Concorde, jet-engine noise and high fuel consumption. Japan has already successfully tested an engine that can theoretically reach speeds of up to mach 5.5, or more than five times the speed of sound.

But test flights of an arrow-shaped test model over the Australian desert have had mixed results.

In one incident, the aircraft prematurely separated from its booster rocket and crashed. Then, in a much-vaunted March 30 trial, the airplane failed to reach its target altitude and the nose cone cover failed to jettison as planned.

Well, now we understand the "nose cone" problem. They're referring to the scramjet experiments performed in Australia recently. But these have nothing to do with supersonic transports. As noted above, the goal doesn't require Mach 5, and scramjets are not necessary for supersonic transports. If the Japanese agency imagines that they do, it will indeed be a long time before they solve the problem.

And the problems with Concorde weren't just "engine noise" and fuel consumption (though the latter was a significant problem). Certainly side-line engine noise needs to be reduced, but this is a problem that results from conventional solutions, which require afterburners to get the low-lift airplane off the ground during takeoff. If they had better takeoff L/D, they wouldn't have an engine noise problem. And this analysis completely ignores the sonic boom issue (though it's not a problem for flight over the oceans). Until they figure this out, supersonic transports won't reach their full potential, which includes transcontinental markets.

As I've pointed out in the past, we won't have economic supersonic flight until we solve the shock-wave problem. Once we do that, we will simultaneously solve the sonic boom and the fuel consumption problems.

Well I think one way to easily solve the shockwave problem would be to fly ballistic arcs above the atmosphere.

Easily, perhaps, but not cheaply. And it still wouldn't solve the problem of booms during ascent and entry.

Perhaps NASA will offer a cash prize for a boomless mach 2 100 passenger SST with the fuel consumption of a 737. That should get the job done pronto! :)

Well, it might, but it would have to be a pretty big prize (on the order of billions). Of course, the market for the thing would be a much better prize.

I have not looked into it. But I think what is behind the supersonic/hypersonic transport thing is NASDA, the Japanese space agency. NASDA has all of the same problems as NASA, just on a smaller scale. They developed the H-2 booster, which is too expensive to use for commercial satellite launch, after spending enormous amounts of money on it.

This hypersonic airliner project is the next boondoggle.

I cannot see Japanese industry being behind this. Japanese industry has been tremendously successful building high-quality, low-cost products for the masses. The economics of a hypersonic airliner go completely against this business strategy.

I was right. It is the Japanese space agency that is behind this. JAXA is the successor organization to NASDA, with all of the same issues.

I don't see the problem, Professor X/Charles Xavier was able to transport his students and teachers at about mach 3, from his tennis court.

> Well, now we understand the "nose cone" problem. They're referring
> to the scramjet experiments performed in Australia recently. But these
> have nothing to do with supersonic transports.

I think they're referring to a separate set of launches, which used a solid-fuel rocket to accelerate a scale model of the SST to Mach 2. No scramjet involved, just a structural model.

http://www.livescience.com/technology/ap_050823_supersonic.html

Apparently, someone thought that would be cheaper than getting wind tunnel time, but since they've run into problems, they've reconsidered. So, the reason they "need some kind of cooperation with NASA" is to get access to the NASA wind tunnels.

Which is not nearly as dramatic as the journalists would lead us to believe.