Winglets

Some more biomimicry from aerodynamic solutions that engineers got out of nature. When we look at the evolution of airplanes, they had to become always bigger and bigger, because more and more people wanted to travel with this transportation method. So more weight has to be kept in air. This is only possible when more lift will be generated. Because the lift is generated by the wings of the airplane, the wing span has to become wider. This has some disadvantages. First of all it will add more weight. Second it will be more difficult to keep the mechanical strength, because the wings become longer and more forces are induced on the wings. The last point is that airplanes will become too large to fly to airports, because the infrastructure is not adapted to the planes. So engineers looked for a solution and they found it by studying an eagle.

An eagle has the capacity to glide through the air without flapping with its wings. They also observed that, on a high altitude, the eagle curved its wing tips. When testing and simulating the curved wing tips, they learned that this reduces the drag that is induced by the lift and that is will increase the lift. Winglets were invented. The winglets prevent that a vortex that is generated under the wings, travels down to the side of the wing and curve on top of the wing. This is what reduces the lift. So by preventing that this will happen, the efficiency is increased and the wing span of the airplane can be less.