Definition
In a turn around a point, the half of the circular ground track during which the airplane is flying with a tailwind component. Because groundspeed is highest in this half, the pilot must use the steepest bank angles here to maintain a constant-radius circle around the reference point.
Plain English
The portion of the circle where the wind is pushing the airplane along, making it travel faster across the ground. To keep the same distance from the point on the ground, the pilot has to bank more steeply during this part of the turn.
Context Anchor
Seen when practicing turns around a point and other ground-reference maneuvers where wind changes the airplane’s path over the ground.
Derivation
“Downwind” means moving with the wind, from the idea of going along the direction the wind is blowing. In this term, it points to the half of the circle where the wind helps carry the airplane across the ground.
Why Pilots Care
Failing to steepen the bank on the downwind half causes the radius to increase, breaking the maneuver and risking drift outside the practice area or into obstacles.
Intuition Check
Do not confuse the downwind half with the downwind leg of a traffic pattern. Here, it means the half of a circular turn where the wind is helping push the airplane over the ground.
Example Sentence 1
As the airplane entered the downwind half of the turn, the pilot smoothly increased the bank angle to hold a constant radius around the silo.
Example Sentence 2
On the downwind half, higher groundspeed means the pilot must roll in more bank than on the upwind side.