Is a tachometer considered a flight instrument?

A tachometer is primarily an instrument that measures the engine's revolutions per minute (RPM), providing crucial information about the engine's performance. While it is an important gauge for monitoring engine operation, it is not classified as a flight instrument. Flight instruments are specifically designed to provide information crucial for the aircraft's altitude, airspeed, heading, and other flight parameters, enabling pilots to safely navigate and control the aircraft during flight.

The tachometer serves a different purpose, focusing on engine performance rather than flight conditions or behaviors. Understanding this distinction clarifies why it is not included in the category of flight instruments, even though it plays a significant role in the overall operation of the aircraft.