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Accident Report Detail

Derailment of Runaway Railcars on Union Pacific Railroad

Executive Summary

In the late morning of June 20, 2003, a string of 31 freight cars that had been part of a Union Pacific Railroad (UP) freight train were cut from their locomotives at a UP siding in Montclair, California. After crewmembers released the cars’ air brakes in preparation for switching the cars in Montclair yard, the cars began rolling. The runaway cars rolled downgrade for about 28 miles and reached a calculated maximum speed of 95 mph before derailing in City of Commerce, California, at 11:58 a.m. Some of the derailed cars struck nearby residences. Three residences were destroyed, and five others were damaged. Thirteen people suffered minor injuries and were transported to local hospitals. About 150 people were evacuated from the area because of broken natural gas and water lines. At the time of the derailment, the sky was overcast; there was no wind; and the temperature was 70° F. Estimated damages were $2.4 million.

Probable Cause

The National Transportation Safety Board determines that the probable cause of the derailment of the runaway cars in City of Commerce, California, was the failure of both the inbound train crew and the switching crew to properly secure the railcars as required by Union Pacific operating rules before the airbrakes were released on the cars. Contributing to the accident was the failure of the Union Pacific Railroad to enforce the application of its operating rules for securing freight equipment before locomotives are uncoupled.

Accident Location: City of Commerce , CA    
Accident Date: 6/20/2003
Accident ID: DCA03FR005

Date Adopted: 4/7/2004
NTSB Number: RAB-04-03
NTIS Number:  

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