Slip-turn

A slip-turn is where an aircraft turns using only the rudder. In most aircraft, the presence of a fixed vertical stabiliser complicates the manoeuvre. However, in those where the whole of the vertical stabiliser comprises the rudder, such as the the Fokker Dr.I triplane, the aircraft can be made to effectively skid in the horizontal plane, a technique employed by the German WWI ace Werner Voss to great effect.