Definition
A downdraft is a localized column of air moving downward, often produced by sinking air in or near a thunderstorm, by air flowing down the lee side of terrain, or by cooling air descending through the surrounding atmosphere.
Plain English
A patch of air that is moving downward. When an aircraft flies into it, the aircraft tends to sink with it.
Context Anchor
Seen in weather, turbulence, mountain flying, and instrument flying discussions about the elevator illusion.
Derivation
From 'down' (direction) plus 'draft,' an old word for a current or flow of air (same root as a draft of air through a doorway). So a downdraft is simply a downward-flowing current of air.
Why Pilots Care
Triggers false pitch sensations that can lead pilots to make incorrect control inputs.
Grounding Statement
Picture a quiet column of air silently sliding downward out of a cloud or off a ridge. Anything flying through that column gets carried down with it until it exits the other side.
Intuition Check
Do not assume a downdraft means the airplane itself has been commanded to descend. The key point is that the air around the airplane is moving downward, and the airplane may be carried with it.
Example Sentence 1
On final approach, the pilot encountered a sudden downdraft and added power to arrest the sink rate.
Example Sentence 2
Recognizing a downdraft early helps the pilot maintain altitude without overcorrecting on the controls.