The National Transportation Safety Board (NTSB) determined that the probable cause of a collision of an Amtrak train with the rear of a Norfolk Southern Railway Co. (Norfolk Southern) train was the failure of the Amtrak engineer to correctly interpret the signal at Englewood interlocking and Amtrak's failure to ensure that the engineer had the competency to correctly interpret the signal across the different territories over which he operated.

On Friday, Nov. 30, 2007, Amtrak passenger train 371, consisting of one locomotive and three passenger cars, struck the rear of standing Norfolk Southern freight train 23M. The forward portion of the Amtrak locomotive came to rest on top of a container on the rear car of the freight train. Sixty-six passengers and five crewmembers were transported to hospitals; two passengers and one crewmember were admitted.

In its report released Tuesday, NTSB found that as the Amtrak train traveled closer to the first signal at Englewood interlocking, the engineer made a significant error when he misinterpreted the meaning of the red over yellow signal aspect. The red over yellow aspect was a restricting indication that required the crew to operate the train at a maximum speed of 15 mph and to be prepared to stop for any trains or obstructions ahead.

The NTSB also determined that contributing to the accident was the relief engineer's failure to immediately communicate to the engineer that he had miscalled the signal at Englewood and to stop the train when the engineer did not respond to her expressed concern. Also contributing to the accident was an absence of effective crew resource management between the relief engineer and the operating engineer which led to their failure to resolve the miscalled signal prior to the collision.

Further contributing to the accident was the absence of a positive train control (PTC) system that would have stopped the Amtrak train when it exceeded restricted speed. The NTSB concluded that had a PTC system been in place, it would have intervened by stopping the Amtrak train when the engineer failed to comply with the restricted speed.

As a result of its investigation of this accident, NTSB made recommendations to the Federal Railroad Administration, Amtrak, the Association of American Railroads, the American Short Line and Regional Railroad Association, the Brotherhood of Locomotive Engineers and Trainmen, the United Transportation Union and the American Public Transportation Association in the following areas: uniform signal aspects to communicate meanings more effectively, wayside signal indication training and proficiency programs, crewmember communication and action in response to operating concerns, and inadequate locomotive cab emergency egress and rescue access.

To view a synopsis of the report, click here.