Definition
The maximum airspeed at which the wing flaps may be extended or operated without risking structural damage. Each flap setting may have its own limit, and these limits are published in the airplane's operating handbook and shown on the airspeed indicator as the upper end of the white arc.
Plain English
The fastest speed you're allowed to fly with the flaps down. Go faster than this with flaps extended and you can damage the flaps or the wing structure that holds them.
Context Anchor
Pilots use this limit before extending flaps during an approach and when checking the airplane’s approved operating limits.
Derivation
“Flap” refers to the movable panels on the wing, and “limit” means a boundary that should not be exceeded. Together, the phrase points to a speed boundary for using the flaps safely.
Why Pilots Care
Exceeding this speed with flaps extended can overload the flap mechanism or wing structure.
Intuition Check
Do not treat flap limit airspeed as a target speed for landing. It is a maximum allowed speed for a flap setting; you may need to be slower before selecting that flap position.
Example Sentence 1
On downwind, the pilot reduced power and waited until the airspeed dropped below the flap limit airspeed before lowering the first notch of flaps.
Example Sentence 2
On final approach the crew verified they were under the flap limit airspeed prior to full extension.