About 6:57 a.m., on May 5, 1976, 25 automobile carriers derailed from Auto-Train Corporation's northbound train No. 4 near Jarratt, Virginia. No one was injured. The train was traveling about 72 mph on the Seaboard Coast Line Railroad (SCL).
The National Transportation Safety Board determines that the probable cause of this accident was an undetected, fractured, loose, and out-of-gauge wheel which struck the track structure. Dragging and incompletely released brakes caused the wheel to overheat at its tread; the overheating caused design stress patterns on the wheel to change and the wheel to fracture. The brakes did not fully release because of the train's length and because of the type of brake equipment used.