NEW CASTLE, Pa. (WKBN) — The National Transportation Safety Board has released a preliminary report with information on what caused the Norfolk Southern train derailment in New Castle.

Through investigation, it was found that an overheated bearing caused the derailment and that a hot bearing detector was attached to the rail line incorrectly, therefor the critical hot wheel bearing alarm message did not reach the crew for the train to be stopped.

According to the report, freight train 14M was headed northbound on the Youngstown Line in New Castle, Pennsylvania when nine mixed-freight railcars derailed, including one carrying hazardous material.

After investigating, officials were able to determine that an overheated wheel bearing caused the derailment.

27 Investigates: Missing equipment along Norfolk Southern’s rail line

Norfolk Southern has hot bearing detectors (HBD) set up along the rail lines to catch overheated bearings and alert the crew. The following is the HBD alarm thresholds (above ambient temperature) and criteria for bearings: ​

  • ​Between 170°F and 200°F, warm bearing (non-critical); the train must immediately reduce speed to 8 mph or slower until the rear of the train clears the detector, at which point the train must be stopped for inspection
  • A difference between bearings on the same axle greater than or equal to 115°F (non-critical); an alert is sent to the ATC desk
  • Greater than 200°F (critical); the crew receives a critical alarm, and the train must be immediately stopped for inspection [7]

When freight train 14M passed over the HBD at MP 91.9, a temperature of 253 F for the east-side bearing on axle 671 (an axle on the 164th railcar).

However, data logs do not show that the advanced train control desk received an alert.

This is most likely due to the fact that the HBD was attached to the rail line improperly.

According to the report, NTSB investigators found that signal maintainers had performed maintenance on the Youngstown Line between Conway Yard and New Castle, Pennsylvania, on May 8, just two days before the derailment. This maintenance included detaching and re-attaching track-mounted components of the HBD at MP 91.9.

It was later determined that the HBD’s transducers were attached incorrectly and reporting reversed train travel directions. So, a northbound train would be reported as southbound.

Although the investigators did not identify any evidence that would have prevented the HBD from sending an alarm message, they did not find any evidence of an audible alarm being broadcast over the locomotive radio when they reviewed the inward-facing image recorder and audio data from the head-end locomotive of train 14M.

In addition to the transducers being attached wrong, preliminary results showed the locomotive’s radio was functional; however, investigators found a loose coaxial connection between the antenna and the radio. On May 16, 2023, NS sent the radio to its radio shop in Roanoke, Virginia, for further analysis and will provide the results to the NTSB.

The NTSB’s investigation is ongoing. The report states that future investigative activity will focus on the analysis of the 164th railcar’s wheelset and bearing, NS use of HBDs, and NS railcar inspection practices.

Norfolk Southern sent out the following statement in response to the release of the report:

“Norfolk Southern continues to cooperate with the NTSB’s investigation and our aim is to learn from what occurred and immediately address any issues that are uncovered. We are always striving to be a better and safer railroad. We have already taken several steps to address how we handle alarms sent by our wayside detectors that monitor for elevated temperatures on railcar wheel bearings and alert crews to a potential bearing failure, which could lead to a derailment.” 

A spokesperson with Norfolk Southern says that without waiting for the NTSB report, they have taken the following action:

  • Enhancing technology to provide multiple means of communicating temperature alarms.
  • Updated systems processes so that wayside alarms are consistently received by the wayside help desk for investigation regardless of their alignment to a specific train. 
  • Enhanced standards for locomotive radio trouble reports.
  • Strengthened the training of standard operating procedures for employees who install and inspect wayside detectors.

Norfolk Southern announced a six-point safety plan on March 6 to enhance the effectiveness of wayside detectors. They have also appointed an outside consultant to lead an independent review of safety practices and a commitment to partner with labor unions to improve safety.