What does the green arc on the airspeed indicator signify?

The green arc on the airspeed indicator signifies the normal operating range of the airplane, which includes speeds that are safe for standard flight operations. This range indicates the speeds at which the aircraft can be flown without risking aerodynamic issues, such as stalling, as well as structural integrity. Pilots refer to this arc to ensure they are within safe operating speeds during various phases of flight, including takeoff, cruise, and landing.

Understanding the significance of the green arc is essential for pilots to maintain control of the aircraft. Operating within this range allows for safe maneuvering and reduces the risk of exceeding speeds that could lead to performance limitations or mechanical failures. Each aircraft will have its own specific range defined by the manufacturer, tailored to the aircraft's design characteristics.