Airliners are flown from a distance

Nowadays, anyone who gets on an airplane has to put up with the accusation of being a climate sinner. A plane is much too big and heavy to float easily through the air. Instead, huge engines accelerate the colossus, blowing vast amounts of pollutants into the air so that the massive wings can make the many tons of weight fly.

Now a European research team, in which the German Aerospace Center (DLR) is involved, has developed new types of wings that could make flying more environmentally friendly in the future. They are lighter, significantly longer and elastic. They were tested for the first time at the special airport in Oberpfaffenhofen near Munich.

Today's planes have stiff wings. They are exposed to high pressure in strong gusts of air or when the aircraft is turning. This creates strong tensions that are transferred to the fuselage of the aircraft. Long wings offer less air resistance and thus make flying more efficient, but the tension also increases. In order to prevent the wings from tearing apart, engineers have to make them very stable, so they are heavy. For this reason, up to now they have not been able to build wings of any length.

The DLR researchers have now developed wings that can twist under high pressure and thus reduce tension. "With gusts and / or strong maneuvers there is more lift and the pressure on the wing increases. The aeroelastic wing rotates outside so that there is no additional lift," explains Wolf-Reiner Krüger the principle. He was responsible for the design of the aeroelastic wing. The rotation is made possible by specially arranged carbon fibers that make the wings elastic. However, the wing only yields in the direction in which the carbon fibers are arranged, otherwise it remains stiff and enables safe flight.

For the time being, the engineers only tested the new wings on one model. It is three and a half meters long and has a wingspan of seven meters. Twice as wide as long: Such an extreme ratio will not exist in conventional cargo and passenger aircraft. In this case, an Airbus A380, the largest passenger aircraft in the world, would have to have a wingspan of over 140 meters. The infrastructure at airports alone does not allow this, the boxes there limit the dimensions to 80 meters.

Nevertheless, there is a tendency towards longer wings, says Krüger. The larger wingspan means that aircraft use less kerosene. Aircraft manufacturers are already trying to take advantage of this fact; the newly developed Boeing 777X, for example, has wing tips that can be folded up at the airport. "This is one of the few cases where economic efficiency and environmental protection coincide," says engineer Krüger.