What is the main use of the airspeed indicator?

The main use of the airspeed indicator is to determine the aircraft's speed relative to the air. This measurement is crucial for a pilot as it provides essential information about the aerodynamic performance of the aircraft. Knowing the airspeed allows pilots to make informed decisions regarding safe operation, including takeoff, landing, and maneuvering.

For example, maintaining the appropriate airspeed during takeoff and landing is vital to prevent stalling. The airspeed indicator helps pilots ensure they are flying at speeds that maintain lift and control responsiveness, which are critical for safe flight operations. Additionally, it helps pilots monitor performance during different phases of flight, such as climb or descent, where adhering to specific airspeeds can significantly enhance safety and efficiency.

While fuel efficiency, altitude maintenance, and stall speed calculations are important aspects of flight operations, they are not the primary function of the airspeed indicator itself. The indicator's primary role is focused on providing real-time airspeed data, which underpins various other operational considerations.