Pilot error generally refers to an accident in which an action or decision made by the pilot was the cause or a contributing factor that led to the accident, but also includes the pilot's failure to make a correct decision or take proper action. Errors are intentional actions that fail to achieve their intended outcomes. Chicago Convention defines accident as "An occurrence associated with the operation of an aircraft [...] in which [...] a person is fatally or seriously injured [...] except when the injuries are [...] inflicted by other persons." Hence the definition of the "pilot error" does not include deliberate crash (and such crash is not an accident).

The causes of pilot error include psychological and physiological human limitations. Various forms of threat and error management have been implemented into pilot training programs to teach crew members how to deal with impending situations that arise throughout the course of a flight.

Accounting for the way human factors influence the actions of pilots is now considered standard practice by accident investigators when examining the chain of events that led to an accident.