accident
A collision or crash of a vehicle, aircraft, or other form of transportation that causes damage to the transportation involved; and sometimes injury or death to the transportation's occupants or bystanders in close proximity. (but see Usage notes)
accident: unplanned event causing transport damage or injury
In transport and logistics, an accident is any unplanned event involving a vehicle, aircraft, vessel, or train that results in damage, injury, or loss. The term covers everything from a forklift striking a warehouse wall to a multi-vehicle motorway pile-up to an aircraft landing gear failure. What unites these events is that they were not intended and they breach normal operational safety. The damage may be minor, confined to equipment; or catastrophic, involving fatalities and total loss of the asset.
The definition matters for insurance, regulatory compliance, and incident reporting. A collision with a stationary object, a rollover, an uncontrolled descent, a fire on deck, or a derailment all count as accidents. However, the term excludes deliberate actions (sabotage, intentional damage) and normal wear or mechanical failure that occurs without a triggering event. This distinction shapes how claims are processed and how liability is determined.
Why the language matters
Transport operators and insurers carefully parse the word 'accident' because it implies an element of unavoidability or bad luck. Regulatory bodies and safety engineers, by contrast, increasingly reject the term, preferring 'incident' or 'crash' or 'collision', since most transport accidents are preventable through better design, training, maintenance, or operational discipline. A driver falling asleep is not an accident; it is a failure of fatigue management. A faulty brake line is not an accident; it is a maintenance failure. This linguistic shift reflects decades of safety research showing that human and organizational factors, not chance, drive most transport losses.
Accident reporting is mandatory in most jurisdictions. Rail accidents are typically reported to a national accident investigation board; aviation accidents to the relevant authority (NTSB in the US, AAIB in the UK); road collisions to local police and insurers. The investigation process reconstructs the sequence of events, identifies root causes, and issues recommendations. Data from accident investigations feeds back into standards, training, and equipment design.
In practice, the line between an accident and a 'close call' or 'near miss' is sharp: did anyone or anything suffer harm? If yes, it is an accident and must be reported. If no, it is a near miss, which should still be investigated but follows a less formal process. Both types of events carry information about system weaknesses and risk.