Definition
A surface incident in which a vehicle, person, or other non-aircraft object enters or moves on any portion of an airport movement area (runways, taxiways, or associated safety areas) without authorization from air traffic control. V/PDs are tracked by the FAA as runway and taxiway safety events because they create collision risk with aircraft operating on the surface.
Plain English
When a car, truck, person, or anything that isn't an aircraft goes onto a runway or taxiway without permission from the tower. The FAA records these because they can lead to a crash with a moving aircraft.
Context Anchor
Seen in airport surface safety, towered airport operations, runway incursion reports, and FAA airport safety material.
Derivation
Deviation means a departure from the correct or expected path, rule, or clearance. In this term, it means the vehicle or pedestrian did not follow the required airport surface control rules.
Why Pilots Care
These events are a leading cause of runway incursions and can force an aircraft to go around or create a collision risk on the ground.
Grounding Statement
Picture a maintenance truck entering a controlled taxiway without tower approval while an aircraft is taxiing nearby.
Intuition Check
Do not read deviation here as just a small difference or mistake. In this FAA context, it means an unauthorized movement by a vehicle or pedestrian in a controlled airport surface area.
Example Sentence 1
The tower filed a V/PD report after a fuel truck crossed the hold line without clearance while a Cessna was on short final.
Example Sentence 2
Reviewing recent V/PD events helps the airport improve signage and vehicle driver training.