Biomimicry

What do Olympic champion Michael Phelps’ swimsuit and the A380 have in common? The answer is a growing field of scientific study looking not at what we can extract from the natural world but what we can learn from it.

Biomimicry is the study and imitation of nature’s best ideas to help solve human challenges. It’s how replicating a shark’s ability to reduce friction and stay clean made Phelps even slicker in the water and protects sensitive surfaces in hospitals.

Over 30 per cent of known species are under threat. For Airbus, the potential damage to the planet and future generations is already disastrous, but it also means the loss of vital sources of inspiration and innovation. Technological innovation has reduced aircraft fuel burn and emissions by 70 per cent and noise by 75 per cent in the last 40 years. The aviation industry contributes two per cent of all manmade CO2 emissions but seeks technological solutions to help reduce that impact even further – and nature might just hold the key.

Ever since Leonardo da Vinci first started sketching aircraft some 500 years ago, aeronautics engineers have learned to draw on nature for their inspiration. David Hills, Airbus senior manager, flight physics research, explains, “Lotus leaves keep clean and dry in damp humid conditions because rainwater runs off and takes dirt with it. This ‘superhydrophobicity’ or ‘lotus effect’ has inspired coatings for cabin fittings that improve hygiene and save water, which also reduces aircraft weight, fuel burn and emissions.

“Sea birds sense gust loads in the air with their beaks and adjust the shape of their wing feathers to suppress lift,” Hills adds. “Probes on the new Airbus A350 XWB detect gusts ahead of the wing and deploy moveable surfaces for more efficient flight.”  

Engineers on the A380 also learned from the Steppe Eagle, a bird of prey native to Europe and Central Asia. If the eagle’s wings are too long, its turning circle would take it outside of the thermal – the rising column of warm air which it uses to gain height. The eagle’s wings perfectly balance maximum lift with minimum length. It can manipulate the feathers at its wingtips, curling them to create a ‘winglet,’ a natural adaptation that aids highly efficient flight. 

For the A380, the issue wasn’t turning inside thermals, but turning inside airports. How could it create enough lift and still fit inside airports, where the wingspan limit is 80 metres? On a conventional wing, vortices created by high pressure air leaks underneath mean the tips don’t provide any lift. The wing has to be longer. Thanks to small devices known as ‘winglets,’ which mimic the eagle’s feathers, the A380’s wings are just 79.8 metres – 20 centimetres inside the limit. The technique is so effective that Airbus applies it to all of its aircraft, both big and small.