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"Airplanes don't flap wings after all." but would be far more economical if they did.

No, they would not. Physics doesn't work that way - you can't just arbitrarily scale things. A bird-sized aircraft can certainly benefit from unsteady aerodynamic viscous force interactions, and insect-sized aircraft don't work without them at all. However, at large scales the inertial forces of the airflow completely dominate the viscous forces. A flapping aircraft large enough to carry a human is possible, but nothing near as simple or efficient as a fixed wing aircraft.

The project has a homepage: http://hpo.ornithopter.net/

Under "technical info", it says

      The key is to produce enough thrust with the wing to keep the aircraft flying at the required
      forward velocity. This thrust is produced by placing the wing at a lower angle of attack,
      relative to the local flow velocity, on the upstroke, and at a higher angle of attack on the
      downstroke. It can be seen in the figure below that this results in a large amount of lift
      and thrust on the downstroke and a small amount of lift and drag on the upstroke. The net
      result is positive lift and positive thrust.

      Throughout the stroke the wing must twist with the proper magnitude and phase to produce the
      proper angles of attack. This is accomplished passively by designing the structure in such a
      way that the aerodynamic and inertial forces produce the proper twist.

So, this is NOT merely a glider.

The up flap does NOT cancel out the down flap

The wings' movement is NOT purely vertical, there is a twist component.

The Project Ornithopter engine-powered piloted aircraft, which is based on the technology of the Harris/DeLaurier model, self accelerated (flapping alone) on level pavement to lift-off speed.

I'm not sure I'd want to fly in a plane with flapping wings, but morphing surfaces might be a boost to these guys, who are working on ornithopters (and must be avid Frank Herbert fans). The video of their 1/4 proof of concept in flight is pretty interesting.

Has anyone noticed that there is a profound difference between a one-person piloted aircraft and the Mentor thing that resembles a broken umbrella/dragon fly dragging a chinese lantern. Or even these things

I thought the article referred to the "Mentor" alfoil thing, not the small flapping one-man aeroplane. But I guess that makes me a slashdot rebel because I read the article?

A certain idiot who shall remain nameless left this out of his post...

Ornithopter.Net

I think these are the same UofT guys who built the smaller model mentioned in the article.

Holy crap I knew the story was old. Slow news day? This verges on antiquity with a 2001 story date. Maybe the slashdot editors could rename the tagline - "No Gnus is nerd Gnus"

Here is the original slashdot story.

Here is a link to the ornithopter website.

Hey, it only took almost another century after the airplane before a stable ornithopter was built.

But there is a valid point in recognising that most A.I. research has been really the search for S.I. (Simulated Intellegence,) using human behavior as the gold standard. To bad many of the better works have tried to be clever with what things are used to generate that behavior. From Rodney Brook's et al. (and most neuro-pathologists) you'd quickly be put in your place about how ridiculously simple and mechanical many of the *hard* behaviors in A.I. were solved by nature.

(viz. a bird's wing is an areofoil, the flapping is only useful for propelling, as the lift-inducing shape is the key; normal walking is unstable semi-harmonic motion driven by reflex feedback.)

Quote at bottom of this /. article's page as of 2003/04/10: Genius doesn't work on an assembly line basis. You can't simply say, "Today I will be brilliant." -- Kirk, "The Ultimate Computer", stardate 4731.3

[frow the useless dept]
Well there's a batch of poeple recently interested in so called Ornythopters (ornitho is for birds) with flapping wings.
Apparently quite difficult, the first real sized one rose 2 meters high on its maiden flight. Small scale one can fly but seem quite difficult to drive where you want.
real size project with videos
small scale model video
Interesting how diffucult this is.
O.

No, you're thinking of this.