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CAS TAS MN

Asked by: 1858 views Instrument Rating 

At a constant calibrated air speed (CAS), Mach number:
-Decreases when altitude increases,
-Increases when altitude increases,
-Remains unchanged when OAT decreases,
-Remains unchanged when OAT increases.

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1 Answers



  1. Josephyr on Mar 01, 2019

    Mach number would increase. Temperature and density decrease with altitude gain, so the speed of sound does as well. This means that a given true velocity, there will be a higher mach number at higher altitudes.

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