Speaker-wings to increase stalling AOA

[flyingcheesehead]

Interesting article:

http://www.smh.com.au/news/national/a-sound-idea/2005/08/18/1123958182084.html?oneclick=true

If it asks for registration, just use ernestq and password word456. (thanks to http://www.bugmenot.com/ )

Here's the important parts:

A Qantas aerospace engineer has found a way to make small planes safer and more efficient by turning their wings into flying speakers that can beat out a tune...

...Instead, he has successfully experimented with covering the upper surface of an aircraft wing with thin film-like panels linked to wires. When the wires are electrified, the panels vibrate 400 times a second, producing an audible buzz.

In wind-tunnel tests at the University of NSW, "singing wings" were able to "fly" at much steeper angles - up to 22 degrees above the horizontal, compared with the normal maximum of about 17 degrees.

"It gives you more of a safety margin, and more time for the pilot to react in an emergency, such as an engine failure on take-off or a sudden wind gust," Mr Salmon said...

The next step would be to test the singing wing on an unmanned aircraft.

Mr Salmon said that if they could make small aircraft perform better at low speed, it should be possible to build planes with smaller wings, which would be lighter, less thirsty, and thus cheaper to fly.

Now, a few questions...

Wouldn't using smaller wings with an increased AOA cause more drag?

How much power would be required, and how much extra engine HP to generate it?

I can see it being added to existing designs as a potential safety enhancement, but how much safer would it really be? It would allow a bit more time to react, but a pilot who'll stall at a 17-degree critical AOA will probably still stall with a 22-degree critical AOA, IMHO.

 

[silver-eagle]

It adds meaning to a "STALL HORN".

 

[gismo]

Unless the "buzzing" wing generates a higher coeficient of lift there's little point in enabling a wing to fly at a higher AoA and there was no mention of this in the article. Also it would be nice to know how much power is required for this and whether or not it would harm the structure.

BTW 400 Hz isn't what I'd call a "buzz". It's higher than middle C on a piano.

 

[gismo]

It adds meaning to a "STALL HORN".

Yeah, if you've pulled up into the high AoA region beyond normal stall and the circuit breaker pops on one wing...