Research conducted by Colin Palmer, an engineer turned paleontology PhD student at Bristol University’s School of Earth Sciences has revealed that pterosaurs, unlike the albatross of today, were in fact too slow and flexible to navigate the stormy winds and waves of the southern ocean.
Palmer used 40 years of experience to construct models of pterosaur wing sections from thin, curved sheets of epoxy resin/carbon fibre composite, which were then tested in a wind tunnel. The tests quantified the two-dimensional characteristics of pterosaur wings for the first time, showing that these creatures were significantly less aerodynamically efficient and were capable of flying at lower speeds than previously thought.
Pterosaurs, also referred to as pterodactyls, had thin-walled bones which made them highly susceptible to impact damage. “Their wings were adapted to a low-speed flight regime that minimizes sink rate. This regime is unsuited to marine style dynamic soaring adopted by many seabirds which requires high flight speed coupled with high aerodynamic efficiency, but is well suited to thermal/slope oaring. The low sink rate would have allowed pterosaurs to use the relatively weak thermal lift found over the sea,” he said.
Their slow flight and variable wing shape enabled them to land gently and relatively safely, helping them to attain much larger sizes than birds in existence today. Palmer said “the trade-off would have been an extreme vulnerability to strong winds and turbulence, both in flight and on the ground, like that experienced by modern-day paragliders.”
Colin Palmer, originally an engineer in ship science, was initially interested in what powered sailing vessels, which eventually lead him to study low speed aerodynamics and the performance of thin airfoils. Palmer is going on to work with students at the Department of Aerospace Engineering where he will undertake more sophisticated aerodynamic analysis using computational fluid dynamics. One day he hopes to be able to create a free-flying model of a pterosaur.