How does a 150-pound bird fly?

"Poorly" might be the answer if this were a joke, but it isn't:

Few prehistoric animals have captured the imaginations of palaeontologists as has Argentavis magnificens, given its enormous size and predatory lifestyle. With a seven-metre wingspan the giant bird was the size of a Cessna 152 aircraft, had a formidable 20 inch skull and eagle-like beak.

As the world’s largest known flying bird the aerodynamics of Argentavis has been fertile ground for speculation for more than two decades. Using software originally written for helicopters, scientists have finally analysed the aerodynamic secrets of the giant bird to reveal how it took off, remained aloft and then landed.

Like today’s condors, it seems Argentavis was a lazy glider that relied either on updrafts in the rocky Andes or thermals, on the grassy pampas, to provide sufficiently lifting power, according to an analysis by Prof Sankar Chatterjee of the Museum of Texas Tech University, Lubbock.

From the Guardian. Note the recent publication of similarly systematic reconstruction of the biomechanics of ol' Tyrannosaurus Rex:

The team used a computer-modeling system to calculate the weight of a fossil specimen from the U.S. and then to estimate its running speed and turning ability, which has never been done before.

That fossil, an average-size adult, weighed between six and eight tons, and some individuals may have been as heavy as ten tons, the researchers said.

The team found the animal, hampered by a long tail and that heavy body, would have taken one to two seconds to make a quarter turn—far slower than a human.

"We now know that a T. rex would have been front-heavy, turned slowly, and could manage no more than a leisurely jog," Hutchinson, the lead study author, said.

Posted by David on July 2, 2007 8:54 PM