NTSB wraps up on-site investigation of Metro-North derailment, cites need for PTC

The National Transportation Safety Board's (NTSB) "go-team" will leave New York City this week after completing an on-scene investigation into the cause of the recent MTA Metro-North Railroad train derailment in the Bronx, agency officials announced Tuesday.

NTSB investigators will continue to gather facts and return to New York as needed for follow-up work, officials said in a press release.

The Dec. 1 accident occurred when a Metro-North train derailed on a sharp curve while traveling at 82 mph in a 30 mph zone. Four passengers were killed and dozens more were injured. The train operator acknowledged nodding off prior to the derailment, according to news media reports. The NTSB investigators have not yet determined the accident's cause, however.

Last weekend, investigators completed mechanical inspection of the train and found no anomalies, nor did they find anomalies with the track or signal system, NTSB officials said. They examined the lead car from which the engineer controlled the train and found that the "dead-man switch," a foot-pedal on the cab floor that must be depressed to keep the train moving, was elevated. The pedal moved and released as expected, with no anomalies noted, they said.

"At this time, the NTSB believes that if positive train control technology was installed on this line and train, it would have required the engineer to slow the train to an appropriate speed or stop the train in the event the engineer did not do so, likely preventing the derailment," officials said.