Lily the barn owl reveals how birds fly in gusty winds

Scientists from the University of Bristol and the Royal Veterinary College have discovered how birds are able to fly in gusty conditions - findings that could inform the development of bio-inspired small-scale aircraft. "Birds routinely fly in high winds close to buildings and terrain - often in gusts as fast as their flight speed. So the ability to cope with strong and sudden changes in wind is essential for their survival and to be able to do things like land safely and capture prey,' said Dr Shane Windsor from the Department of Aerospace Engineering at the University of Bristol. "We know birds cope amazingly well in conditions which challenge engineered air vehicles of a similar size but, until now, we didn't understand the mechanics behind it,' said Dr Windsor. The study, published in Proceedings of the Royal Society B , reveals how bird wings act as a suspension system to cope with changing wind conditions. The team used an innovative combination of high-speed, video-based 3D surface reconstruction, computed tomography (CT) scans, and computational fluid dynamics (CFD) to understand how birds 'reject' gusts through wing morphing, i.e. by changing the shape and posture of their wings. In the experiment, conducted in the Structure and Motion Laboratory at the Royal Veterinary College, the team filmed Lily, a barn owl, gliding through a range of fan-generated vertical gusts, the strongest of which was as fast as her flight speed.