The National Transportation Safety Board released a preliminary report Thursday about the toxic train derailment earlier this month in East Palestine, Ohio. Thirty-eight cars derailed in the Feb. 3 crash, including 11 tank cars carrying chemicals including vinyl chloride.
“NTSB investigators identified and examined the first railcar to derail, the 23rd railcar in the consist,” the NTSB report said. “Surveillance video from a local residence showed what appeared to be a wheel bearing in the final stage of overheat failure
moments before the derailment.”
It said the wheel bearing and affected wheelset have been collected as evidence and will be a focus of further investigation.
According to the report, the train was traveling 47 miles per hour, slightly below the 50 mile per hour speed limit, but the alarm for a hot axle was triggered three times.
At first, the axle was 38 degrees above ambient temperature, according to recordings taken by a wayside defect detector, also called a hot bearing detector (HBD). By the second alert, the axle was 103 degrees above ambient tempreature. When the third alert went off, it was 253 degrees above ambient.
According to the NTSB, a recorded temperature 200 degrees above ambient is considered “critical” and the train must stop.
The HBD “transmitted an audible alarm message instructing the crew to slow and stop the train” after registering the critical temperature, the NTSB said.
The train came to a stop. Crew then observed fire and smoke and notified dispatchers of a possible derailment.