1. The actual critical Mach number varies from wing to wing. 2. The true airspeed corresponding to the critical Mach number generally decreases with altitude. 3. The Me 262 appeared to have a higher critical Mach number than any American fighter. 4. These problematic phenomena appearing at or above the critical Mach number became known as compressibility. 5. A swept wing delays the onset of this problem by increasing the critical Mach number . 6. The wing-and tail-thickness ratio was also reduced to increase the critical Mach number . 7. At the "'lower critical Mach number "', airflow around the entire aircraft is subsonic. 8. At the "'upper critical Mach number "', airflow around the entire aircraft is supersonic. 9. The aircraft Mach number at which these effects appear is known as its critical Mach number , or M CRIT. 10. For high subsonic flows, the Critical Mach number ( M 1cr ) is a characteristic value of considerable importance.
