Birds flap wings during landing to maintain control, study finds
New physics research suggests wing-flapping is a practical solution to aerodynamic challenges rather than wasted energy.
New physics research published in Proceedings of the Royal Society A suggests that birds flap their wings during landing to solve difficult aerodynamic problems, according to a Times of India report.
While gliding consumes less energy than flapping, researchers found that stopping without powered wing movements is impractical for most real-world scenarios.
Mathematical modelling by University of Manchester researchers Tom Rottier and Ben Parslew, alongside Philippe Lavoie of the University of Toronto, tested zero-speed landings without flapping.
The model showed that a pigeon-sized bird attempting to stop without flapping would require an initial speed more than twice its cruising speed, a 20-metre climb, and roughly 60 metres of horizontal travel.
Dr Ben Parslew stated that landing involves more than just slowing down, as a bird must decrease speed while keeping enough aerodynamic control to finish the manoeuvre safely.
By using bursts of thrust and lift, birds can adjust their path late in the approach and land at manageable speeds within short distances.
The study also noted that birds of prey, such as Harris’s hawks, may swoop below a perch to balance low landing speeds with the need to limit time spent in a less controllable state.
These findings regarding low-speed control and energy absorption could eventually inform the design of drones and other aerial vehicles.