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
Alexander Mach Alexander Mach Alexander Mach (11 October 1902 in Slovenský Meder (today Palárikovo) – 15 October 1980 in Bratislava) was a Slovak nationalist politician. Mach was associated with the far right wing of Slovak nationalism and became noted for his strong support of Nazism and Germany. Mach joined the Slovak People's Party at an early age and came to prominence within that movement as an aide to Vojtech Tuka. Under Tuka's tutelage Mach served as editor of the party organs "Slovak" and "Slovenska Pravda" and was appointed to the party's political committee in 1924. He belonged to the non-clerical wing of