Definition
VLO is the maximum airspeed at which the landing gear can be safely extended or retracted on a retractable-gear aircraft. Operating the gear above this speed risks structural damage to the gear, gear doors, or the actuating mechanism due to high aerodynamic loads during transit.
Plain English
The fastest you’re allowed to be flying when you put the gear down or bring it up. Move the gear lever above this speed and you can damage the gear system.
Context Anchor
Seen in aircraft speed-limit markings, checklists, and flight manual limitations for airplanes with retractable landing gear.
Derivation
The subscript 'LO' stands for 'landing gear operating' — the speed limit that applies while the gear is in motion (extending or retracting), as distinct from VLE, which applies once the gear is fully extended.
Why Pilots Care
Exceeding VLO risks damage to the landing gear doors or retraction mechanism.
Analogy
Think of it like a speed limit for opening or closing a mechanical part. The aircraft may be able to fly faster, but the gear mechanism has its own safe speed limit while it is moving.
Intuition Check
Do not read operating speed as the airplane's normal flying speed. Here, operating means moving the landing gear up or down.
Example Sentence 1
After takeoff, the pilot waited until the airspeed was below VLO before retracting the gear.
Example Sentence 2
VLO is always lower than VLE, so the gear must be operated only after slowing further.