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Human Error & Mechanical Failure Contributed to Derailment

NEWARK, NJ – Three days into a comprehensive investigation of Train 3920’s derailment, NJ TRANSIT today issued its preliminary findings on the cause of the incident and is launching a review of on-board emergency response procedures.

NJDOT Commissioner and NJ TRANSIT Board Chairman Jack Lettiere and NJ TRANSIT Executive Director George D. Warrington announced that the preliminary results of the investigation point to two factors – human error and mechanical failure -- that contributed to the incident.

Commissioner Lettiere said, “Our customers, particularly those on board train 3920, deserve to know what happened, how it happened and what we are doing to prevent something like this from happening again – sooner rather than later. This preliminary investigation begins to answers those questions.”

Based upon all available evidence to date, the officials said that the preliminary report indicates train 3920 struck some debris enroute from Trenton. The debris strike caused the bearing seal in the wheel assembly of car number 1368 to be damaged between the gear unit and the bearing housing. This damage and subsequent overheating caused the bearing to seize up and fail.

The investigation also found that at railroad Mile Post 29.7 near Edison, Amtrak’s wayside hot wheel scanner detected excessive heat and signaled to the dispatcher that the wheel was overheating.

“The protocol in these instances is clear – and is guided by both NJ TRANSIT rules and Amtrak special instructions to crews,” said Warrington. “The conductor is required to use a Tempilstik device on a specific part of the wheel assembly to determine whether the surface temperature has exceeded 200 degrees. Proper performance of this type of inspection would have detected an impending wheel failure. As a result, all of our train crews will immediately be re-trained in safety and inspection protocols within the next 60 days.”

Later in the train’s journey, the bearing failure led to the separation of the wheel from the axle, according to the investigating team’s findings.

Warrington said that as a result of these preliminary findings, NJ TRANSIT will initiate a disciplinary process for the train’s conductor -- consistent with union contractual requirements -- and pursue a hearing process to determine his responsibility in the apparent failure to properly inspect the wheel condition and take corrective action. Following the hearing, if guilt is found, appropriate disciplinary action will be taken. Pending the outcome of the hearing, the conductor will remain out of service without pay.

In addition, the investigating team found no evidence of material defect or concerns associated with maintenance practices. However, in the interest of “absolute safety,” Warrington said the Corporation will take the additional precaution of downloading daily the computers on the 115 Arrow III cars that have traction motors, to monitor for any abnormalities. Warrington has also instructed that NJ TRANSIT’s mechanical engineering staff look at developing a shield for the key portion of the wheel assembly to prevent future debris strikes from doing catastrophic damage.

Working with an outside metallurgical expert, the Corporation is having the performance of the wheel assembly analyzed on the Arrow III car that lost a wheel. The full report from metallurgy studies will not be available for at least 30 days. NJ TRANSIT will finalize its investigation subsequent to receiving the metallurgist’s final report.

The investigation revealed that instructions and assistance rendered to train 3920’s passengers immediately following the derailment were inadequate. While the first NJ TRANSIT manager was on the scene within 20 minutes, the on-board public address system was not operational following the derailment.

“It is clear that on-board emergency response plans and contingency protocols need to be improved,” Warrington said.

He has directed a task force to review all aspects of customer care and communications during this event, including interviewing the customers aboard train 3920, and will make public the recommendations and actions the Corporation will undertake. The task force will thoroughly review crew size, evacuation protocols, emergency communications and passenger information on what to do in the event of an emergency.

Lettiere added: “There are important lessons to be learned from this incident and we will overhaul our practices accordingly.”

NJ TRANSIT is the nation's largest statewide public transportation system providing more than 752,600 daily trips on 238 bus routes, two light rail lines and 11 commuter rail lines. It is the third largest transit system in the country with 161 rail stations, 28 light rail stations and more than 17,000 bus stops linking major points in New Jersey, New York and Philadelphia.