Definition
A nose-up pitching moment that develops as an airplane lifts off and climbs out of ground effect, caused by the rearward shift of the wing's center of lift and the increased downwash striking the horizontal stabilizer once the wing is no longer close to the ground.
Plain English
As the airplane climbs away from the runway, the nose wants to rise on its own. The pilot has to be ready to push forward slightly to keep the airplane from pitching up too much.
Context Anchor
Seen during takeoff discussions, especially when the airplane is flying very close to the runway in ground effect.
Derivation
“Pitch” in aviation means nose-up or nose-down rotation. “Up” shows the direction of that rotation, and “tendency” means a natural leaning or habit. Together, the term means the airplane has a natural leaning to rotate nose-up.
Why Pilots Care
If unanticipated, the sudden nose rise can lead to over-rotation, tail strike, or stall shortly after liftoff.
Grounding Statement
Picture the airplane just lifting off, close to the runway, with the nose trying to rise a little more than the pilot asked for.
Intuition Check
Do not read “pitch” as sound or sales talk here. In this context, pitch means the airplane’s nose-up or nose-down attitude.
Example Sentence 1
Just after liftoff, the instructor warned the student to expect a pitch-up tendency as the airplane climbed out of ground effect.
Example Sentence 2
Knowing the pitch-up tendency appears in ground effect lets the pilot plan smoother rotation during takeoff.