On May 28, 2008, about 10:05 a.m., southbound Chicago Transit Authority (CTA) Green Line train 003 traveling on elevated track between Harlem/Lake Avenue station and Cottage Grove derailed after crossing switch 85A, which was lined against the direction of the train at south main track marker 338 in Chicago, Illinois. Train 003 consisted of four passenger cars coupled in sets of two. There were 24 passengers onboard. Fourteen passengers sustained minor injuries and were transported to area hospitals, where they were treated and released; the other 10 passengers declined medical attention. The total property damage to track, cars, and signal equipment was about $338,000. At the time of the derailment, the winds were variable at 11 mph, visibility was 10 miles, and the temperature was 52º F.
We determined that the probable cause of the May 28, 2008, derailment of Chicago Transit Authority Green Line train 003 was the train operator’s failure to observe, recognize, and act on the stop (red) signal indication at signal 86. Contributing to the accident was the operator’s failure to comply with the operating instructions that specified the required actions to be taken after an emergency brake application. Also contributing to the accident was the lack of a positive train control system that would have stopped the train before the red signal when the operator did not respond properly, thereby preventing the derailment.
