Definition
The lowest airspeed at which an aircraft is capable of sustaining flight in a given configuration. Below this speed the wing can no longer produce enough lift to support the weight of the aircraft, and controlled flight cannot be maintained.
Plain English
The slowest the aircraft can go and still stay in the air. Any slower and the wing stops carrying the airplane.
Context Anchor
Seen in takeoff and landing performance discussions, especially when judging liftoff speed, approach speed, and the slow-speed area just before touchdown.
Derivation
Minimum comes from the Latin word minimus, meaning “smallest.” In this term, it points to the lower limit of usable flying speed, not simply a comfortable or recommended slow speed.
Why Pilots Care
Takeoff and landing speeds are set safely above minimum flying speed. Knowing where that lower edge sits helps a pilot understand stall margin, especially when heavy, in turns, or in gusty conditions.
Grounding Statement
At minimum flying speed, the airplane is just barely getting enough air over the wings and controls to stay controllable.
Intuition Check
Minimum does not mean “best slow speed” or “safe slow speed.” It means the lower limit at which controlled flight is still possible in that situation.
Example Sentence 1
At maximum gross weight the aircraft's minimum flying speed is higher than it is when lightly loaded.
Example Sentence 2
Knowing the minimum flying speed let the instructor set a safe margin for the initial climb after liftoff.