Which engine instrument measures the revolution speed of the engine?

The tachometer is the instrument designed specifically to measure the revolution speed of the engine, typically expressed in revolutions per minute (RPM). This measurement is crucial for monitoring engine performance and ensuring it operates within safe limits. Understanding the RPM helps pilots and engineers maintain optimal engine conditions, as different speeds can affect fuel efficiency, power output, and overall engine health.

Other instruments, such as the engine pressure ratio, measure the efficiency of the engine in terms of pressure, while a fuel pressure gauge indicates the fuel supply status to the engine. The exhaust gas temperature gauge monitors the temperature of the gases exiting the engine, which assists in determining combustion efficiency and detecting potential issues. However, none of these instruments specifically measure engine speed, making the tachometer the sole instrument for this function.