NTSB: Communication breakdown led to UWS subway train collision, derailment

NEW YORK - The NTSB has released its preliminary report into the derailment of a 1 train earlier this month that left 22 passengers and 3 crew members injured.

In the incident, a disruptive passenger vandalized a subway train on the Upper West Side, causing the crew to stop the train and leading to a low-speed crash between trains.

According to the NTSB, the crash happened due to a communication breakdown. As the 1 train approached the 96th Street Station, radio communication was lost between the train's flagger and the supervisor.

That miscommunication led to the train running a red signal and colliding with another train, which was executing a track crossover. 

The track in the area was equipped with trip-stops, which activate a train's emergency brakes if a train passes through a signal requiring a stop, but because the brakes on the first five railcars had been cut out, the emergency brakes could not be activated by the trip-stop. 

The NTSB's investigation will continue to focus on operational and communication protocols for NYC Transit and broader issues like federal requirements for railcar event recorders.