Angle of Attack

What is Angle of Attack?

The angle between an airfoil's chord line and the direction of the oncoming relative wind, one of the primary variables a pilot controls to generate lift. Increase it and lift climbs steadily — until the flow can no longer follow the upper surface and separates abruptly, the moment of aerodynamic stall.

The five clues

Engineerdle #19 described Angle of Attack with five clues, revealed one at a time from hardest to most direct. Each clue points at a different property of the concept.

1. 01An angle measured between two things, neither of which is the horizon.
2. 02One reference is the wing's chord line; the other is the oncoming airflow.
3. 03Increase it and lift generally increases too — up to a point.
4. 04Push it too far and the flow separates entirely from the upper surface.
5. 05The angle between an airfoil's chord line and the direction of the oncoming relative wind.