Safety board investigators raised concerns about the need for the CTA to improve protection against unintended train movements, saying that unoccupied CTA trains are “routinely left powered-up while stored and with the brake setting that would allow movement.’’
The runaway four-car train was parked in the yard, at the western terminus of the Forest Park branch, with power to the propulsion system, lights and other equipment activated for possibly days before the incident, said a source close to the investigation, speaking on condition of anonymity.
The new developments surfaced as the NTSB issued two “urgent safety recommendations’’ Friday addressing “the need for redundant protection to prevent unintended train movements on the CTA system.’’
In the emergency recommendations, the NTSB disclosed that the four-car train traveled almost 1 mile downhill through five mechanical train stop mechanisms before reaching the Harlem station, where it struck the standing eight-car train.
During the incident, the emergency brakes were applied and the train was momentarily stopped several times by the mechanical train stop mechanisms, called “trips,’’ as it proceeded to the Harlem station.
“After each stop, the train started moving again because the master lever on the operator console had been left in a setting that allowed the train car brakes to recover and reset from the emergency brake application and proceed through a mechanical train stop mechanism after a momentary stop,’’ the NTSB report accompanying the recommendations said.
CTA officials could not be reached immediately for comment.