Chicken Tikka Massala (CTM) is the way to remember this.
Climb : - CAS TAS Mach +
______________________
Descent : - Mach TAS CAS +
Eg climbing at constant CAS, TAS & Mach Number increase.
Climb at constant Mach, TAS and CAS are decreasing.
Descend at constant Mach, TAS and CAS increase.
Descend at constant CAS, mach number and TAS decreasing.
The four examples above highlight nicely what is happening as you jet climbs or descends through the changeover height.
(written by fATPL 200hr wannabee who stands ready to be corrected - was a while ago I did Performance
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