Mach number a small area around the object's leading edge. (Fig.1b) Fig. 1. "Mach number in transonic airflow around an airfoil; M < 1 (a) and M > 1 (b)." When an aircraft exceeds Mach 1 (i.e. the sound barrier), a large pressure difference is created just in front of the aircraft. This abrupt pressure difference, called a shock wave, spreads backward and outward from the aircraft in a cone shape (a so-called Mach cone). It is this shock wave that causes the sonic boom heard as a fast moving aircraft travels overhead. A person inside the aircraft will not hear this.
Kawasaki S1 Mach I Mach I emerged nearly one year after its bigger brother, the S2 Mach II 350, and from the development success of the Kawasaki H1 Mach III. It was essentially the same motorcycle as its larger brother with less displacement. It had a separate handlebar holder and steering friction damper. Its successor, the KH250, was essentially the same bike with a different name, was marketed from 1976 to 1981. Kawasaki S1 Mach I The Kawasaki Mach I (model designation S1) was a Kawasaki motorcycle made 1972 through 1975. The Mach I was a direct result of the widespread success of the