Airbus aircraft demonstrates freely flapping wing-tips
Airbus’ AlbatrossONE demonstrator has successfully achieved a new milestone: a “gate-to-gate” demonstration with wing-tips that are 75% longer than those tested in the first phase. This latest flight test campaign proves freely flapping wing-tips can alleviate wing loads and avoid tip stall for improved aircraft performance.
Thanks to its uncanny ability to travel over long distances with little fatigue, the albatross seabird has a lot to teach aeronautical engineers about improving aircraft performance. And the Airbus AlbatrossONE project team is taking keen interest in this majestic seabird, putting the principles of freely flapping wing-tips—capable of reacting and flexing to wind gusts—to the test.
This small-scale, remote-controlled aircraft demonstrator, which features “semi-aeroelastic” hinged wing-tips, recently completed a successful second flight test campaign.
Airbus Semi-Aeroelastic Hinge Project Leader Tom Wilson said, “The albatross’ wing-tips are actually somewhat analogous to semi-aeroelastic hinged wing-tips. The albatross can “lock” its wings at the shoulder to travel long distances, but when faced with wind gusts, it can “unlock” its shoulder to better navigate wind speeds. Semi-aeroelastic hinged wing-tips behave in the exact same way.”
AlbatrossONE Chief Engineer James Kirk in discussing the potential of this innovative technology for future aircraft said, “Semi-aeroelastic hinged wing-tips enable an aircraft to “surf” through wind gusts without transferring the bending loads (i.e. external load that produces bending stresses within a body) to the main wing. This means we require less material, such as carbon-fibre-reinforced polymers, to make the wing strong enough to withstand the gust loads, thus reducing the weight of the aircraft. Also, the length of the wing-tip can be extended without adding weight to the wing because the extra loads from the longer wing-tip are not passed to the main wing.”
The lengthy semi-aeroelastic hinged wing-tips would reduce drag, leading to significant reductions in fuel burn and CO2 emissions.