Secret of eagles' landing revealed

[Dann Pigdon <dannj@alphalink.com.au>]

Secret of eagles' landing revealed
16 April 2007
--

Jumbo jets do it, pterosaurs used to do it - and now we know that eagles do 
it too. As they come in to land, planes, prehistoric reptiles and steppe 
eagles deploy a flap on the front edge of the wing. 

Using a high-speed video camera, Anna Carruthers and her colleagues from the 
University of Oxford filmed a male steppe eagle (Aquila nipalensis) as it 
touched down on its handler's arm. The 500-frames-per-second camera caught 
the wing-flap movement as a feathery "travelling wave" that spread from the 
wrist of the wing to the shoulder. Previous footage had been too slow to 
catch this movement. 

Carruthers says that the wave appears to be initiated automatically when 
aerodynamic conditions change as the bird slows down to land, probably to 
act as a stabiliser or to maintain lift at low speed. She says the finding 
could help develop bird-sized surveillance aircraft known as micro air 
vehicles. 

"The potential of the high-speed camera approach is enormous," says Matthew 
Wilkinson, an animal flight researcher at the University of Cambridge. "It's 
given us an unprecedented insight into the workings of an eagle wing." Other 
large birds are also thought to use front-edge wing flaps. 

From issue 2599 of New Scientist magazine, 16 April 2007, page 19
http://www.newscientist.com/article/mg19425995.700-secret-of-eagles-landing- 
revealed.html 

___________________________________________________________________ 

Dann Pigdon
GIS / Archaeologist         http://www.geocities.com/dannsdinosaurs
Melbourne, Australia        http://heretichides.soffiles.com
___________________________________________________________________