NTSB alerts transit, commuter railroads to check wheelsets

The National Transportation Safety Board (NTSB) yesterday issued a safety alert calling on transit-rail agencies and commuter railroads to assess their fleets for wheelsets that do not meet gauge specifications and to immediately correct any problems.

The alert urges transit agencies and commuter railroads to address a condition in which wheels on certain rail cars in the Washington Metropolitan Area Transit Authority (WMATA) system moved outward from their mounted position on the axle, NTSB officials said in a press release.

"The safety alert identifies the issue of wheelset movement on transit rail cars and commuter railroads as a serious problem that has the potential to create a catastrophic event," said Robert Hall, director of the NTSB Office of Railroad, Pipeline and Hazardous Materials Investigations. "As we continue to conduct the investigation of this derailment, it is imperative that the safety issues identified are addressed immediately to protect the American public traveling daily on our transit system."

An out-of-specification wheelset is not easily identifiable with a routine visual inspection. Consequently, the condition could exist on wheel and axle assemblies of other transit or commuter rail cars, NTSB officials said.

The wheelset movement issue was identified during NTSB’s ongoing investigation of the Oct. 12 derailment involving a WMATA train traveling southbound on Metrorail’s Blue Line between the Rosslyn and Arlington Cemetery stations in Arlington, Virginia.

Of the 187 passengers onboard, one passenger was transported to the hospital for treatment.

In a preliminary report issued yesterday, NTSB investigators said the train had departed the Rosslyn station when one wheelset on the fourth car of the train derailed. After it derailed, the train traveled about 1,800 feet before stopping in the tunnel. All rail cars remained upright and inline.

A preliminary review of data from an onboard event recorder revealed the train speed was about 33 mph at the time of the derailment. Based on physical evidence and station video review, between the Arlington Cemetery and Rosslyn stations, one of the car’s wheelsets derailed and rerailed while moving through a pair of switches.

The train continued traveling toward the Largo Town Center station. NTSB found that when the train departed that station, the same wheelset on the derailed and rerailed again while moving through a pair of switches. The train continued inbound through Washington, D.C. toward Arlington, where the accident occurred.

The NTSB investigation of the derailment is ongoing.