UNION PACIFIC TRAIN ACCIDENTS
UNION PACIFIC
TRAIN ACCIDENTS
Office of Railroad Safety
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At about 8:40 a.m., mountain standard time, March 16, 1997, Union Pacific Railroad freight train 01 MBSMF2 13 (SP 8031 West), derailed nine cars near Kinter, Arizona. The train was traveling at 40 mph when the brakes applied in emergency. The conductor inspected the train and discovered the derailed cars, 18 cars behind the locomotives. Five of the derailed cars were crossways and the trailers and containers were thrown off the cars dumping their contents.
The majority of the cars derailed at milepost (MP) 750.2. Further inspection of the track revealed that the initial point of derailment was at MP 754.7. One set of wheels marked the ties between MP 754.7 and MP 750.2.
Inspection of the truck vans loaded on the flat car 18 behind the locomotives, revealed that large rolls of paper shifted to one side of the van’s interior. There was no evidence of the proper bracing material in the vans as required by the guidelines published by the Association of American Railroads (AAR).
Postaccident inspection of the flat car carrying the truck vans revealed neither clearance measurements nor wear indications in excess of those prescribed by 49 Code of Federal Regulations, Part 231. The measurements were also within tolerance of the standards set by the carrier which are more restrictive than the Federal regulation. However, the wheel of this car displayed a considerable amount of defacement on the outside rim. Due to the mechanical assembly of the 3-piece railroad truck (based on a center pin for rotation), when a load shifts its weight and applies pressure on one side of the truck more than the other, the truck can no longer steer. Therefore, the car has difficulty in negotiating curves. If the pressure is severe enough the truck will not turn and will continue straight and derail.
Most likely when this car was traveling through the 6° curve at MP 754.7 with the paper rolls shifted to one side of the van, the railroad car would have listed to one side. The physical leaning of the car would have applied pressure on the 3-piece truck and it would not have rotated through the curve. The set of wheels would have continued straight derailing to the outside of the curve.
INJURY TABLE
| Injury
Type |
Train Crew on
1MBSMF2 13 |
Others | TOTAL |
| FATAL | 0 | 0 | 0 |
| SERIOUS | 0 | 0 | 0 |
| MINOR | 0 | 0 | 0 |
| TOTAL | 0 | 0 | 0 |
Total: $1,283,000.00
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