The Board continues to investigate the January 7, 2007 derailment of a Washington Metropolitan Area Transit Authority (WMATA) rail car near the Mount Vernon Square station on the Green Line. The following is an update on that investigation.
The team is completing documenting and measuring track structures near the crossover where the derailment occurred. Survey of the accident scene is in progress. The team is in the process of reviewing historical data and inspection records for that area of track.
The derailed equipment (fifth car in consist) has been moved to the Branch Avenue Maintenance Facility. The event recorder (VMS) data is being downloaded for that car and is in the process of being read out at the NTSB laboratory. Teardown inspection of the 5th and 6th cars is in progress. The teardown will involve measuring and documenting all mechanical systems on the trucks (i.e. braking system, leveling system, etc) and a complete inspection and documentation of each wheel and axle components.
Board investigators have reviewed maintenance records and noted that the derailed car had undergone maintenance on Friday, January 5, 2007, two days before the accident. The Safety Board is still reviewing the details of the maintenance work.
The train operator has been interviewed. The operator provided a preliminary timeline of events leading up to the derailment that will supplement data logs and communication recordings that are being reviewed. In addition, the train operator provided information regarding the process that was followed after the derailment to confirm and report the derailment to emergency response personnel. The fire department communications have been requested and the signal data captured are in the process of being reviewed. The following documentation has been collected and is under review by Safety Board investigators:
* Rules, procedures and work history records
* Dispatcher and signal data logs
* Radio and telephone recordings
Factual reports will be developed and placed in the public docket at a later time.