Machmeter

instrument

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Last updated

June 30, 2026

Quick Summary

A Machmeter is an instrument used to measure the Mach number. The Mach number represents the ratio of an object's speed, such as an aircraft, to the speed of sound in the surrounding medium.123

Mach number < 1: Indicates subsonic flow.
Mach number > 1: Indicates supersonic flow.

When an object moves faster than the speed of sound (Mach number greater than one), shock waves can form due to the compression of the surrounding fluid. A Machmeter is essentially an airspeed indicator specifically calibrated to display this Mach number directly.32

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airspeed indicator
…the speed of sound, called Machmeters, are used.
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…the speed of sound, called Machmeters, are used.
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avionics
Performance instruments include the altimeter, Machmeter, turn and slip indicator, and varied devices that show airspeed, vertical velocity, and angle of attack. Communications instruments include two-way radios allowing direct voice communication between the aircraft and the ground as well as other aircraft; these operate across a wide spectrum, ranging from…
Read More
Performance instruments include the altimeter, Machmeter, turn and slip indicator, and varied devices that show airspeed, vertical velocity, and angle of attack. Communications instruments include two-way radios allowing direct voice communication between the aircraft and the ground as well as other aircraft; these operate across a wide spectrum, ranging from…
Read More