How can you confirm that the airspeed indicator is functioning correctly during the takeoff roll?

Confirming that the airspeed indicator is functioning correctly during the takeoff roll primarily involves observing its response to changes in speed. As the aircraft accelerates down the runway, the airspeed indicator should show an increase in speed, which is critical for determining the appropriate time to rotate and take off safely.

Airspeed indicators operate based on differential pressure, where the difference between the static pressure and the dynamic pressure (which varies with speed) provides an accurate reading of the aircraft's speed through the air. Thus, if the indicator is moving and increasing appropriately, it indicates that the system is responding to the airflow around the aircraft, affirming its operational integrity.

Comparing the airspeed indicator to the altimeter is not a reliable method for confirming airspeed operation since the altimeter measures altitude, not speed. Likewise, while GPS speed can provide an indication of ground speed, it does not directly correlate to the aircraft's airspeed, which is what is primarily needed for takeoff. Observing other aircraft does not offer any direct indication of the functionality of your own airspeed indicator and would not be a practical means of assessment during your own takeoff roll.