Critical Mach number Critical Mach number In aerodynamics, the critical Mach number (Mcr or M* ) of an aircraft is the lowest Mach number at which the airflow over some point of the aircraft reaches the speed of sound, but does not exceed it. At the lower critical Mach number, airflow around the entire aircraft is subsonic. At the upper critical Mach number, airflow around the entire aircraft is supersonic. For an aircraft in flight, the speed of the airflow around the aircraft differs considerably in places from the airspeed of the aircraft; this is due to the airflow having to speed up
Mach Five of his father's motor company). In the 1993 American remake, the design was completely changed. Its name probably derives from the fact that speeds above Mach 5 are known as hypersonic. However, the Mach Five cannot reach Mach speeds. The name is also a pun in two languages: the word for "five" in Japanese is "go". However, the "go" used for the car's name is a suffix attached to the names of ships, etc. Thus, the car is known in the Japanese version as simply the "Mach". Actual race cars that closely resemble the Mach Five are the 1966 Japanese