The National Transportation Safety Board determines that the probable cause of this accident was the separation of a severely worn steering linkage ball joint connection which resulted in the jamming of the steering linkage and prevented the driver's controlling the steering of the bus. Contributing to the cause of the accident were ineffective inspection procedures followed by both the operator and the State inspection agency which failed to detect the worn ball joint assembly, and the steering system design which included mechanical components that could deteriorate with no forewarning and which did not incorporated
Abstract