NORFOLK, Va. — In a formal petition filed with the National Transportation Safety Board, Norfolk Southern Railway Company presented documentation and analysis, including new evidence, clearly establishing good cause for the NTSB to reexamine and amend its conclusion regarding the cause of an Oct. 20, 2006, derailment in New Brighton, Pa.
The NTSB’s assertion that the accident was caused by an “inadequate rail inspection and maintenance program” is contrary to both the new and previously available evidence provided to the agency during its original investigation, NS said.
The immediate cause of the New Brighton accident was a rail fracture that occurred when an eastbound freight train passed over the track. As a result, 23 rail cars loaded with ethanol derailed, and many caught on fire. There were no injuries to the train crew or public. Norfolk Southern’s response to the derailment, including addressing the needs of nearby residents, was deemed appropriate by the NTSB.
The main focus of the NTSB’s investigation was an Aug. 1, 2006, ultrasonic rail inspection. The NTSB claims that one of the 24 ultrasonic signals was interrupted and, as a result, a defect in the rail was not discovered. The NTSB concludes that the rail defect would have been discovered if the ultrasonic signal had not been interrupted.
Countering that conclusion, Norfolk Southern’s rail inspection contractor recently verified that the operator of the inspection vehicle, having observed a possible defect on an adjacent rail, immediately conducted a second ultrasonic test. This second test ensured that all 24 ultrasonic signals were being continuously sent.
This data produced by the operator’s second test was provided to the NTSB after it announced its determination of probable cause at a public meeting held on May 13, 2008, but before the issuance of its July 25, 2008, Accident Report.
The defect that ultimately led to the derailment was not detected by the ultrasonic test conducted nine weeks earlier, because despite the use of the best technology available the defect either did not exist or was too small to be detected.
“The NTSB’s findings and recommendations should be based upon the complete facts,” said Tim Drake, Norfolk Southern’s vice president engineering. “Based on the uncontroverted, scientifically-proven evidence Norfolk Southern has furnished, the NTSB lacks a factual basis to determine that our track and maintenance program is inadequate, and we urge the Board to correct its erroneous conclusions.”
“We have provided irrefutable proof that the derailment was caused by a defect that could not have been detected by the advanced technologies used during the Aug. 1, 2006, track inspection,” said Drake. “Norfolk Southern has the lowest track-related accident rate among Class 1 railroads, and even the NTSB has recognized that we inspect our track for internal defects more frequently than required by the Federal Railroad Administration.”