On Apr 21, 12:57*pm, Larry Dighera wrote:
If this technique can be adapted to gliders and other aircraft,
imagine the enabling effect it will produce:

http://technology.newscientist.com/c...-shapeshifting...
* * * * Shape-shifting skin to reduce drag on planes and subs

* * * * * 13:30 16 April 2008
* * * * * NewScientist.com news service
* * * * * Colin Barras

* * Engineers have shown skin able to tune its wrinkles could cut
* * dramatically cut drag on submarines or planes (Image: IOP)
* * Engineers have shown skin able to tune its wrinkles could cut
* * dramatically cut drag on submarines or planes (Image: IOP)

* * Aircraft or submarines covered with an undulating skin able to
* * change at a flick of a button would experience 50% less drag than
* * conventional vehicles. This trick, which naturally occurs in
* * dolphins, is now being tested by human engineers.

* * Turbulence is the bane of engineers' lives. Chaotic air flow sets
* * up unstable vortices and patterns in gases and liquids, increasing
* * friction and drag.

* * Giving craft skin than can tweak its surface to impose order on
* * these currents could dramatically cut the effect of drag, says
* * Dimitris Lagoudas at Texas A&M University, US. Calming the chaotic
* * waves makes them interact less with the skin. "The particles in
* * the fluid stop "speaking" to the craft’s surface," he says.

* * Lagoudas and colleagues have worked out that wrinkling the surface
* * of a craft in the right way can cut problems. The surface must
* * assume the shape of the ideal ordered surface wave it is trying to
* * create, something that changes at different velocities.

* * Dolphin trick

* * It might seem counterintuitive to reduce drag by wrinkling the
* * surface of a craft, but nature provides a precedent. "Dolphins
* * induce their skin to wrinkle, so water won’t stick to them," says
* * Lagoudas.

* * After calculating that this approach would work, his team tested
* * designs for an "active skin" that shifts to ...

More...http://technology.newscientist.com/c...-shapeshifting...

Yesterday I was talking about something like this with my CFI and we
discussed the idea of dimpling an airplane like a golf ball. The
upper surfaces of the wings would remain smooth but the fuselage and
undersides of the wing would be dimpled to reduce drag.