The MTA is still investigating what caused a F train carrying almost 1000 passengers to derail in Woodside, Queens a week ago–injuring 19 passengers, 4 of them seriously–but investigators have identified a few clues that may hold the answer.
The section of track where the F went off the rails last Friday was only installed a matter of weeks before, at the end of February, and the section had not yet been inspected by the MTA’s geometry train.
The track geometry car (what the MTA calls “New York City Transit’s Wonder Train Car“) is a two-car train that uses ultrasound, thermal imaging, lasers and high-resolution video to measure things like the curvature and alignment of the track, and its smoothness.
According to the MTA, before the derailment the tracks were inspected by workers who walked the tracks twice a week, but an official confirmed the geometry car had not tested that stretch of track before the derailment.
That could mean a problem might have gone unnoticed because, as Antonio Cabrera, the MTA’s Assistant Chief Officer of Track Engineering, explained to a group of journalists just a few days before the derailment, the geometry car “can find things that no human eye would be able to find.”
After the derailment the MTA says the geometry car was run along the full length of the subway tracks. An MTA official added that the 39 foot, 1,300 pound rail was also tested by the manufacturer, steel giant ArcelorMittal, before it was shipped to the MTA in December 2013.
The derailment happened in one of five a critical rail break corridors identified in a committee presentation before the new rail was installed in February.