This paper provides a description of "Unintended Acceleration" (UA) in passenger cars. It presents data pertaining to the scope of the problem as defined by the number of accidents and injuries reported annually to the National Highway Traffic Safety Administration (NHTSA) that are alleged to be associated with UA. The paper also discusses the causes of UA and countermeasures to reduce the incidence of UA. The paper provides analysis to assess the reductions in reported UA-related accident rates which have resulted from the use of automatic shift locks. UA reports are defined as incidents of high-powered unwanted vehicle acceleration from a stationary position or very slow speed, accompanied by reportedly slow speed, accompanied by reportedly ineffective brakes. Based on data obtained from NHTSA's computerized consumer complaint file system, and information obtained in the course of agency defect investigations, the paper concludes that the best known countermeasure to UA has been factory installation of automatic shift lock systems which prevent the driver from shifting the transmission out of Park unless the brake pedal is simultaneously applied.
Abstract