NTSB: Green Line train that hit 2nd train was going 30 mph Aug. 2, 2021 FacebookTwitterEmail BOSTON (AP) — The Green Line train that struck a second train on Friday was traveling at 30 miles per hour, while the train that was struck was traveling at about 10 mph, according to a preliminary review of data by the National Transportation Safety Board. The NTSB said in a press release Monday that the collision occurred on the Commonwealth Avenue rail grade crossing leading into the Pleasant Street Station, which is currently closed and under construction. As a result of the collision, two cars of the leading train and one car of the trailing train derailed.