What describes wind blowing at an angle to the line of an aircraft?

The term that accurately describes wind blowing at an angle to the line of an aircraft is crosswind. When wind interacts with an aircraft from a direction that is not directly head-on or from behind, it creates crosswinds. This condition can affect the aircraft's ground track and requires skillful handling by the pilot to maintain proper aerodynamic control during takeoff, landing, or while in flight. Crosswinds are an important factor to consider for runway alignment and can have a significant impact on the aircraft's approach and departure angles.

In contrast, headwinds blow directly against the aircraft, providing increased lift and slowing its forward movement relative to the ground, while tailwinds blow from behind, which can enhance ground speed. Updrafts refer to vertical wind movements, rising air that can lift the aircraft but does not pertain to wind blowing at an angle to the aircraft's direction. Understanding these wind types is crucial in aviation, particularly for safe takeoff and landing operations.