What does the white arc on the airspeed indicator indicate?

The white arc on the airspeed indicator indicates the flap operating range. This range specifies the airspeeds within which the aircraft can safely operate with the flaps extended. Operating within this range is crucial for maintaining control and preventing potential aerodynamic complications, especially during takeoff and landing phases when flaps are typically used to enhance lift at lower speeds.

Flaps are designed to increase drag and lift at slow speeds, enabling better performance during these critical flight stages. Exceeding the speeds indicated by the white arc while flaps are extended could lead to a stall or structural damage, as the aerodynamic forces acting on the wings change. Therefore, it's essential for pilots to be familiar with the airspeed limits associated with flap extension to ensure safe operation of the aircraft.

Understanding the context of the airspeed indicator is key to flying safely, and recognizing the significance of the white arc emphasizes the importance of appropriate speed management while using flaps.