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."

Comments

Engine Noise?

[niteguy]

I thought the problem was the sonic booms, not the engine noise. A little difficult to fly from New York to Tokyo in six hours if you've gotta go around South America, isn't it?

Re:Engine Noise?

[Analogy Man]

Right you are that engine noise is not the big issue...but you're a little confused about going around South America. For NY to Tokyo the great circle route would be over the arctic not around the south end (stretch a string point to point on a globe).

In the 1995 timeframe I was at Boeing working on the HSCT program (Mach 2.4, 300 passengers...). The performance numbers were working out pretty well. Economics were encouraging to the point that it would slay the super jumbo since their markets overlapped (who would do choose a 14 hour flight if a 5 hour one was the same cost?). With respect to takeoff performance the wing loading at takeoff is light enough that noise profiles can be managed. Also, since this sort of airplane is likely to primarily operate out of large airports takeoff/noise performance is not the issue. In the day, overland would be down around Mach 1.4 - 1.7 rather than design point 2.4.

The big technical challenges were:

• materials (although this was workable)
• emissions - not so much the quantity versus transonic aircraft but due to flying at 60,000 feet instead of at 35,000 ft. I am not an expert on the atmospheric sciences, but if I recall there was concern with triggering cloud formation and Nit. Oxide causing ozone depletion.
• I did write an AIAA paper on analysis methods for predicting boom propogation and the issue was that even trans-pacific there are a lot of islands and ships out there regardless of how big and open it looks on a map, not to mention marine life (whales, seals, sea bird rookeries) issues. Some things can be done to soften the boom, but you just can't completely mitigate the physics of the shock wave of a 600,000 lb object traveling at Mach 2.4.

2015? MAN....

[Spy der Mann]

could be in operation by 2015

I'm betting that by 2015 there'll be a technology to make even faster yets which will hold up to 1000 people.

Is it just me, or it really seems that large scale technological advances are going TOO slow?

Re:Don't forget the other factors

[Balthisar]

I know the parent is cliche now, but dang it, I've had many opportunities to fly some of the Mexican airlinelines lately, and it reminds me of the way things used to be. Hot meals. Silverware. The *whole* can of soda. Free booze (yeah, even domestic flights). Pillows. Blankets. Little doily-things on the headrest so the previous passenger's grease wouldn't infect your head. In flight magazine (yeah, in English). Enough legroom for my 6'2" body. And all of this in tourist class. And you know, on my last flight, I bought the tickets a couple of days in advance, and it was the same price as when I'd checked them a month in advance.

And just to show that I'm still a little sexist, latina stewardesses of the highest calibre.

Supersonic workaround

[kc01]

Okay, it's been said above that the U.S. doesn't allow supersonic travel between its borders. True, for commercial aircraft.

Still:

1. There's no reason why it couldn't be used for supersonic travel between New York and Europe.
2. There's no reason why it couldn't be used for supersonic travel between California and Asia.
3. For flights that go over the U.S., like New York to Tokyo, there's nothing that says the pilots can't throttle back to subsonic speeds while over land, is there?

If it's fast and fuel/cost/environmentally efficient, I say bring it on. It'll probably be a lot easier to implement than suborbital flight.

Re:Innovation?

[be-fan]

Yes and no. "Innovation" is a bit of a silly word in the engineering world. Engineering is mostly about "evolution" not "revolution". Occasionally, you see something like the SR-71, which break every existing mold, but such designs are few and far between. Consider something like the Boeing 787. It's claim to fame is a 20% increase in efficiency. To an aerospace engineer, that's huge. They'd trade their first-born for a 10% decrease in specific fuel consumption. To hit that 20%, a lot of innovations had to go into the design. But consider the big picture: is the 787, as a whole, really innovative? Not really.

Japan's aerospace industry in particular is very interested in technologies that even lay-people would see as "revolutionary". For example, if you research the field of hypersonic planes, a lot of that work is being done in Japan. In the United States, the focus is a bit different. Things have become not so much about "faster and higher", but "better, more efficient, and cheaper". Both are innovative in a way, but the former is more "sexy".

Re:Does it represent a shift?

[vought]

Does it really [represent a shift away from the U.S. by Japan] or are they just trying to benefit from France's experiences with the concorde for this project?

I'm sure it's for both reasons; a big deal was made of Japan's growing skill and interest in building their own large aircraft parts during the '90s.

Boeing executives were little bit wary about outsourcing so much of the 777's fine machine work and wing structural work to Japanese firms - partially because they knew Japan would one day be ready to build large aircraft on their own.

Japanese firms have learned a lot about how to build an aircraft from us over the past ten or so years, and now they're shifting toward working with the French, who have experience in the specific type of comercial travel they're interested in building for.

really?

[KH]

I've read the news at BBC. It states

Companies from the countries will split an annual investment of $1.84m (£1.01m) for research over the next three years, Japan's trade ministry said.

That sounds like an awful little money for such a project. I'm really not sure if they actually are planning to build working planes.

On the other hand, this makes some sense. The French not only participated in Concorde, but have been making supersonic fighter jets for a long time. It appears France is only country who can still build supersonic jets with 100% ingenious technology. And it's a major member of the European consortium (Airbus).

There have long been a frustration in the Japanese aerospace industry that the Americans banned them from pursuing cutting edge aerospace technology after the WWII. It is a commonly held view that the US didn't want Japan to acquire know-how in that area so that she can independently develop and compete in the military aircraft field. (Mitsubishi, Kawasaki, and Subaru used to make airplanes. Look where they went.) So, the US kept supplying technology to Japan while not allowing ingenious know-how to accumulate.

A famous incidence was when the Japanese were planning a new fighter/attack plane. Those in the uniform wanted to go ingenious design (they always want to go domestic even when the equipment is prohibitively expensive), but because of the pressure from the States, it became a joint project between Japan and the US based on F-16 design. The result Mitsubishi F-2 is mediocre at best.

I would imagine there is a genuine fear that aerospace industry gets monopolised by Americans in the near future among other countries. So, a supersonic passenger plane appears to be a good excusable exercise to develop and accumulate the technology, especially when Americans are not seriously doing it.

NOT a law of Physics!

[XNormal]

It's NOT a law of physics that an object moving through a fluid faster than the speed of sound must generate a shock wave. The Navier-Stokes do have solutions at supersonic speed that do not involve a discontinuity in pressure (shock wave).

A supersonic bullet not generating a sonic boom was designed in the 60s so if a sniper misses the target on the first attempt the target will not get a warning (the noise of a bullet is supersonic boom. Muzzle noise is far away and supposedly masked by a silencer). The bullet has a cylindrical shape with completely straight outer edge and internally it has a carefully designed inlet coupled to a carefully designed expansion nozzle.

It doesn't generate any aerodynamic lift. Generating lift would require breaking the symmetry and that, of course, would break the careful arrangement that eliminates the shockwave. An airplane must generate lift and there it would seem that this effect cannot be used. However, an airplane also has an engine. If the engine's energy is added to the equasions there can be solutions that generate lift and still have no pressure discontinuities. These mathematical solutions are proven to exist, but haven't been found, yet. If they are found, there is no guarantee that thay can be made into a practical airplane - but there's NO law of physics saying it's impossible!

Note that the shockwave CAN be reduced by orders of magnitude by careful design down to the point where it's probably not a problem. Here I am talking about totally eliminating it in the mathematical sense.