Define 'airspeed' and its significance in flight.

Airspeed is defined as the speed of an aircraft relative to the surrounding air. This measurement is significant in flight for several reasons, primarily because it directly influences an aircraft’s lift and control characteristics.

Lift is generated when air flows over and under the wings of the aircraft; a specific airspeed is required to create enough lift to allow the aircraft to ascend or maintain level flight. If the airspeed falls below a certain threshold, the aircraft can stall, leading to a loss of control. Therefore, understanding and managing airspeed is critical for a pilot to ensure safe operation.

Additionally, airspeed affects various aspects of flight dynamics, including maneuverability. Faster speeds typically allow for more responsive control inputs, while slower speeds may lead to reduced handling effectiveness. Thus, maintaining appropriate airspeed is essential for the safety and performance of an aircraft throughout all phases of flight.