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mediumdistance-speed

Mach number is the ratio of:

TAS to the local speed of sound. Mach number = TAS / local speed of sound (LSS). At FL350 with LSS around 575 kt, Mach 0.80 = TAS of 460 kt.

TAS to the local speed of sound

IAS to CAS

GS to TAS

CAS to EAS

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