How can a pilot determine the wind direction during flight?

Determining wind direction during flight is effectively achieved by observing the drift of the aircraft over the ground. This process involves comparing the actual track of the aircraft against its heading. If the aircraft appears to be moving away from its intended flight path, it indicates that wind is affecting its movement. By assessing the angle and rate of this drift, pilots can infer the direction and strength of the wind acting on the aircraft.

This method is practical in-flight because it provides real-time feedback based on the interaction between the wind and the aircraft's performance. It allows pilots to make necessary adjustments to maintain the desired course, improving navigation accuracy.

While the other options may provide some information about wind conditions, they do not offer the immediate, in-flight assessment that drift observations do. Instruments can show wind speed and direction, but may not account for real-time atmospheric changes. Weather reports are helpful before takeoff but cannot predict localized wind variations encountered during flight. Asking Air Traffic Control can provide general information, but it is ultimately up to the pilot to evaluate and respond to wind conditions actively encountered during the flight.