Critical Mach number and slow down as it travels around the aircraft's structure. When the aircraft's airspeed reaches the critical Mach number, the speed of the airflow in some areas near the airframe reaches the speed of sound, even though the aircraft itself has an airspeed lower than Mach 1.0. This creates a weak shock wave. As the aircraft exceeds the critical Mach number, its drag coefficient increases suddenly, causing dramatically increased drag, and, in an aircraft not designed for transonic or supersonic speeds, changes to the airflow over the flight control surfaces lead to deterioration in control of the aircraft. In aircraft
Bluebird Mach 1.1 Bluebird Mach 1.1 Bluebird Mach 1.1 (CMN-8) was a design for a rocket-powered supersonic land speed record car, planned by Donald Campbell but thwarted by his subsequent death during a water speed record attempt in "Bluebird K7" in early 1967. Donald Campbell decided a massive jump in speed was called for following his successful 1964 LSR attempt in "Bluebird CN7". His vision was of a supersonic rocket car with a potential maximum speed of 840 mph, referred to as "Bluebird Mach 1.1". Norris Brothers were requested to undertake a design study. Campbell, ever superstitious, chose a lucky date to hold