Asked by: Michael Turner, Pontefract
Forward-swept wings are unusual, but one of the better-known recent designs is the Russian experimental fighter, the Sukhoi Su-47 Berkut. With the tips located forward of the point where the wings connect to the fuselage, the plane almost looks as if it is travelling backwards in flight.
Forward-swept wings make an aircraft harder to fly, but the advantages are mainly down to manoeuvrability. They maintain airflow over their surfaces at steeper climb angles than conventional planes, which means the nose can point higher without the aircraft going into a dangerous stall. In addition, their aerodynamic properties change less between subsonic and supersonic flight than swept-back wings, meaning that the Su-47 is well suited to transonic flight – in other words, at speeds close to the sound barrier.
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