Mach Number

Definition

The ratio of true airspeed to the local speed of sound. Mach 1.0 is the speed of sound, which varies with temperature and altitude. Transport aircraft typically cruise between Mach 0.78 and 0.85.

Related Terms

Critical Mach Number(Mcrit)

The Mach number at which airflow over some part of the aircraft first reaches th...

Mach Tuck

A nose-down pitching tendency that occurs when shock waves on the wing move the ...

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