Swept wings on supersonic aircraft usually lie within the cone-shaped shock wave produced at the nose of the aircraft so will "see" subsonic airflow and work as a subsonic wing. The angle needed to lie behind the cone increases with increasing speed, at Mach 1.3 the angle is about 45 degrees, at Mach 2.0 it is 60 degrees.[10] The angle of the Mach cone formed off the body of the aircraft will be at about sinμ = 1/M (μ is the sweep angle of the Mach cone)[11]