Definition
The angular difference between an aircraft's heading (the direction its nose is pointed) and its track (the actual path it follows over the ground), caused by wind pushing the aircraft sideways during flight.
Plain English
The angle between where the nose is pointing and where the airplane is actually going, because the wind is blowing it off to one side.
Context Anchor
You meet drift angle when correcting for wind during navigation, ground reference maneuvers, and approaches to a runway.
Derivation
‘Drift’ comes from Old Norse and Middle English, meaning to be carried along by a current. In aviation, the airplane is being ‘carried along’ sideways by the wind, even while pointed in its original direction.
Why Pilots Care
It determines the heading adjustment needed to stay on the desired ground track and avoid drifting off course.
Grounding Statement
Imagine pointing a boat straight across a river, but the current pushes you downstream. The angle between where the bow points and where you actually end up is the drift angle.
Intuition Check
Drift angle does not mean the airplane is sliding sideways through the air. It means the ground path is not the same as the direction the nose is pointed.
Example Sentence 1
With a strong crosswind, the pilot noted a drift angle of about 8 degrees and turned the nose into the wind to stay on course.
Example Sentence 2
On the return leg the drift angle reversed, requiring an opposite heading adjustment to maintain the same ground track.