Definition
VLO is the maximum airspeed at which the landing gear can be safely extended or retracted. Operating the gear above this speed risks structural damage to the gear, gear doors, and associated mechanisms due to the aerodynamic loads encountered during the transit cycle.
Plain English
The fastest speed you're allowed to be flying when you raise or lower the landing gear. Above this speed, the wind loads on the moving gear can damage it.
Context Anchor
Seen in the airplane flight manual and used during approach, landing, go-around planning, and any checklist step that involves extending or retracting the landing gear.
Derivation
The 'V' stands for velocity, the standard prefix used across aviation airspeed limits. 'LO' stands for landing gear operating — the act of moving the gear up or down. So VLO = velocity, landing gear, operating.
Why Pilots Care
Exceeding VLO while extending or retracting the gear can overstress the gear doors, actuators, or structure.
Intuition Check
Do not read operating speed as the speed for any flight with the gear involved. VLO is the limit for moving the landing gear; a different limit may apply when the gear is already fully down.
Example Sentence 1
On downwind, the pilot reduced power and waited until the airspeed was below VLO before lowering the landing gear.
Example Sentence 2
During the go-around the crew waited until airspeed dropped under VLO before retracting the gear.