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Does it matter? Well, the first to build a working waverider aircraft was a Scottish amateur rocketry group. Story has it that when NASA and Boeing engineers saw footage of the vehicle flying, they were staring at the screen in sheer envy. They'd got no further than theory. We also all know the story of the New Zealander who has jet-propelled go-karts and his own low-cost cruise missile. And the Gauss Rifle linked to above didn't look too complex, either.

Although amateurs are very unlikely to be building supersonic or hypersonic spy planes in the near future, none of this looks so complex that it could not be done by other nations in comparable time. Don't think it won't happen - too many potential benefits. Variants will also inevitably be adopted by commercial space planes, as it's so much cheaper than using vanilla rocketry and should be much more reliable.

To me, the only question I think worth asking at this point is who will be there first? Lockheed-Martin, China or Rutan? (And after Lockheed's disastrous hovering shuttle replacement in the late 1990s, it's not wise to just assume they'll automatically win such a race.)

The first to prove that such a wing has minimum wave drag was R.T. Jones (1951). More recently, inviscid CFD calculations proved that the best performances are obtained with a wing of aspect-ratio 10:1 with a cruise CL=0.068. The best yaw angle would be 68 degrees, and the wing would have the flying operation shown in Fig. 1 below.

Hmm, I could be wrong about this, but flocking behavior is *vastly* more complex than the three points that listed in the parent's post.

From what I understand, flocking doesn't result from just 'following the birds adjacent to you', but instead a result of optimizing a complex multiplanar lifting system in order to reduce total flight power demand.

Honestly, I'd be suprised if the researchers were able to emulate the real purpose of a flock, instead of just emulating superficial swarming behavior -- there was a very readable article in Science written by two guys at Caltech on flight efficiency & flocking, and they conclude with the premise that: "theoretically 25 birds could have a range increase of about 70 percent as compared with a lone bird"

IMO, programmed swarming behavior is nothing new, but if these researchers run with the ball and generate *real* efficiency-optimizing flocking behavior with man-made aircraft, the ramifactions could be huge.

• Waverider theory
  
• More Waverider theory
  
• My God, Hardware! - the experience of a Scottish Astronautics research group (I suggest reading the whole piece, the link points to the middle of the story, 'cos of the great quote!)
  

The NASA design is example 4 on the summary page and is quoted there as having a theoretical top speed of Mach 20.

The BBC has some good pics and information too.

According to this page, it may be even more impressive than that.

You got it backwards.

Read the thread before you post...

They are talking about the fact that there will be SOME gas in the tube, not much, but it will be there.

Aerospace engineers have been doing this kind of problem in the lab for years, we call them shock tubes, you can also check google.

Dr. Kroo was one of the only academics to work closely with the inventor of an even more radical concept called the Oblique All Wing (aka Oblique Flying Wing) Supersonic Transport. The OAW SST concept originated in the 1940s with supersonics pioneer Robert Theo Jones (who preferred to be called "RT Jones").

I became interested in Jones' concept when an article (very similar to the one available online from Hiller Museum of Aviation) appeared in "The West" magazine in the early 90s. The thing that hooked me about the idea was that RT Jones had originated the supersonics models for swept wings used for all of aviation and had come to the conclusion that:

1. The optimal supersonic wing was an ellipse with no body that tilted into the wind more and more as it went faster and faster -- an amazingly simple and elegant concept.
2. The price per passenger mile for a trans-Pacific flight would be no more than for a 747 even though the flight time would be half.

Having hooked me at the time I was most active in aerospace politics I decided to look into why the supersonic wind tunnel at NASA Ames wasn't being utilized by the Stanford crew under the ultimate mentorship of RT Jones (who it was obvious to me, was nearing the end of his functioning life). As it turns out there were some problems with NASA HQ not wanting to have confusing signals sent to Congress about which direction NASA was going to go with its High Speed Civil Transport program. There were funds at stake here. At one point NASA Ames attempted to take a small part of its "discretionary" budget and fund the supersonic wind tunnel runs of a model of the OAW SST, but when it did so NASA HQ got "wind" of it and not only forbade the research but docked NASA Ames an equal amount of money in the next year's "discretionary" budget.

When I heard about this, I became angry.

I plunked down some dough and flew RT down to meet with Congressman Ron Packard (R 43rd district CA) and discuss the situation. We got some other Congressmen to look at the situation a bit as well. The real clincher didn't happen until I discovered the person with the most intimate knowledge of the supersonic modeling equations was going to work for Airbus after having been trained by RT Jones at Stanford. This gave me the leverage I needed to push the "American Competitiveness" buttons with the Congressmen -- and I did just that.

This had repercussions.

The initial result was a specific line item in the NASA bill. This was to send a signal to NASA HQ that they weren't to stop the supersonic windtunnel testing from going forward at NASA Ames -- that the OAW SST model from Stanford and RT Jones would be experimentally tested against the equations. The second result was that someone's head was going to roll for letting the cat out of the bag about NASA HQ's bad behavior. I think the guy who got demoted was Tom Gregory even though he wasn't the source of the dirt -- so I have to apologize to him for the consequences of my rather heavy-handed politics -- but the consequences for the testing were at least a little good.

The tests got run, finally.

RT Jones was pretty sick the last time I talked to him -- and discouraged. The fact is he was within a few years of dying of a prolonged illness. He didn't think it was worth pursuing the OAW SST anymore -- that a subsonic 747 style jet could be made more comfortable for the long flight. It was sad hearing him talk that way about his brain child but it was understandable given the life-long struggle for acceptance of the idea and his weakened state. Nevertheless, the idea remains an intriguing if not viable one -- and someday I hope there is at least a FedEx next-business-day robotic package OAW SST fueled by methane -- the system I first thought would be viable.

Dr. Kroo was one of the only academics to work closely with the inventor of an even more radical concept called the Oblique All Wing (aka Oblique Flying Wing) Supersonic Transport. The OAW SST concept originated in the 1940s with supersonics pioneer Robert Theo Jones (who preferred to be called "RT Jones").

I became interested in Jones' concept when an article (very similar to the one available online from Hiller Museum of Aviation) appeared in "The West" magazine in the early 90s. The thing that hooked me about the idea was that RT Jones had originated the supersonics models for swept wings used for all of aviation and had come to the conclusion that:

1. The optimal supersonic wing was an ellipse with no body that tilted into the wind more and more as it went faster and faster -- an amazingly simple and elegant concept.
2. The price per passenger mile for a trans-Pacific flight would be no more than for a 747 even though the flight time would be half.

Having hooked me at the time I was most active in aerospace politics I decided to look into why the supersonic wind tunnel at NASA Ames wasn't being utilized by the Stanford crew under the ultimate mentorship of RT Jones (who it was obvious to me, was nearing the end of his functioning life). As it turns out there were some problems with NASA HQ not wanting to have confusing signals sent to Congress about which direction NASA was going to go with its High Speed Civil Transport program. There were funds at stake here. At one point NASA Ames attempted to take a small part of its "discretionary" budget and fund the supersonic wind tunnel runs of a model of the OAW SST, but when it did so NASA HQ got "wind" of it and not only forbade the research but docked NASA Ames an equal amount of money in the next year's "discretionary" budget.

When I heard about this, I became angry.

I plunked down some dough and flew RT down to meet with Congressman Ron Packard (R 43rd district CA) and discuss the situation. We got some other Congressmen to look at the situation a bit as well. The real clincher didn't happen until I discovered the person with the most intimate knowledge of the supersonic modeling equations was going to work for Airbus after having been trained by RT Jones at Stanford. This gave me the leverage I needed to push the "American Competitiveness" buttons with the Congressmen -- and I did just that.

This had repercussions.

The initial result was a specific line item in the NASA bill. This was to send a signal to NASA HQ that they weren't to stop the supersonic windtunnel testing from going forward at NASA Ames -- that the OAW SST model from Stanford and RT Jones would be experimentally tested against the equations. The second result was that someone's head was going to roll for letting the cat out of the bag about NASA HQ's bad behavior. I think the guy who got demoted was Tom Gregory even though he wasn't the source of the dirt -- so I have to apologize to him for the consequences of my rather heavy-handed politics -- but the consequences for the testing were at least a little good.

The tests got run, finally.

RT Jones was pretty sick the last time I talked to him -- and discouraged. The fact is he was within a few years of dying of a prolonged illness. He didn't think it was worth pursuing the OAW SST anymore -- that a subsonic 747 style jet could be made more comfortable for the long flight. It was sad hearing him talk that way about his brain child but it was understandable given the life-long struggle for acceptance of the idea and his weakened state. Nevertheless, the idea remains an intriguing if not viable one -- and someday I hope there is at least a FedEx next-business-day robotic package OAW SST fueled by methane -- the system I first thought would be viable.

Sounds like another potential use for carbon nanotubes. After all, if they're strong enough to build a space elevator (see earlier /. article) they're probably strong enough to make a helicopter, right?