sonic boom/sonic bangs

The bangs heard when shock waves generated by a transonic or supersonic aircraft strike the ears of an observer on the ground. When an aircraft is flying at a speed faster than the speed of sound, shock waves form on the aircraft. These shock waves radiate out from the aircraft in the form of a cone. When the cone passes over the ground, the pressure difference between the pressure inside the shock wave and the pressure of the surrounding air causes the explosion-like sound.