mach indicator

[ARGPILOT]

mach indicator supply the relation between speed of sound and ?

ias
tas
eas
cas ?

thanks

[NigelOnDraft]

Mach......

[Shaka Zulu]

Any of the above but it depends on how big the formula is you want to make!
TAS is the normal speed used

[BelArgUSA]

Mach/TAS computations

Hola Che -
xxx
The TAS of Mach 1 is 661 knots at 15º C static air temperature.
It varies with temperature ONLY (altitude does NOT change anything).
If temperature increases, say 25º C, Mach 1 will be 671 knots TAS...
If temperature decreases, -56º C SAT, Mach 1 will be 574 Knots...
xxx
That is the best I can read on my Jepps CR-3 slide rule...
So, Mach .85 with -56º C (standard temp at FL 360) is 488 knots TAS.
If temperature increases to -46º C (still at FL 360, Mach .85), it is 498 knots...
xxx

Happy contrails

[ORAC]

Atmospheric Properties Calculator

[Old Smokey]

Mach Number is very simply the ratio of your present TAS to the local speed of sound, thus, Mach Number per se, is directly ralated to TAS.

From the manometric aspect Mach Number is gauged from CAS (i.e. Total Pressure in the Pitot tube minus static) Vs ambient pressure (or Pressure Height), that's how it is gauged, but the end result is the relationship between your current TAS and the local speed of sound.

FYI, the relationship between Mach Number and CAS (IAS) is governed by Static Pressure (Ps, Pressure Height) ALONE, Ambient Temperature has NOTHING to do with the relationship between CAS and Mach Number, only Pressure Height. (The same for EAS).

Regards,

Old Smokey