ATPL: Critical Mach number is the free stream Mach number at which:
Domanda 221, Principles of Flight - ATPL - Airline Transport Pilot license
| There is subsonic flow over all parts of the aeroplane. |
| Local supersonic flow first exists on any part of the aeroplane. |
| The aeroplane has zero buffet margin. |
| There is supersonic flow over all parts of the aeroplane. |
