The operator of the Chicago Transit Authority train that derailed at O'Hare International Airport early Monday told the National Transportation Safety Board that she dozed off before the crash.
"She did admit that she dozed off prior to entering the station," NTSB investigator-in-charge Ted Turpin said. "She did not awake again until the train hit close to the end of the bumper."
The eight-car Blue Line train jumped the tracks and landed on the stairs and escalators leading to the airport terminals just before 3 a.m. The crash left 32 people injured, and three passengers have since filed lawsuits against the CTA.
The NTSB estimates the crash caused about $6 million in equipment damage.
Turpin told reporters Wednesday this isn't the first time the operator fell asleep on the job.
During an interview Tuesday with the NTSB, officials say she admitted to dozing off while operating a train in February and passed a station without stopping. She was just beyond that station when she realized she was too far to open the doors, Turpin said.
CTA officials later clarified that the operator said she "closed her eyes for a moment," but did not indicate that she "dozed off" during the February incident. The CTA also says the train did actually stop and only one car passed the station. The operator then made an announcement that the train would proceed to the next station and did not open the train doors because the train had not properly stopped at the station, according to the CTA.
The CTA says the operator is currently on Injured on Duty status, and that her second safety violation could lead to her dismissal. The CTA plans to take action after its investigation is completed.
Turpin said the operator was hired in April 2013 and entered the training program for operators in October. She became a qualified operator in January, and at the time of the crash she had been running trains for about 60 days.
She typically fills in for other operators and her hours vary, Turpin said. Her last shift started around 10 p.m. Sunday, and she was scheduled to make five round trips between Logan Square and O'Hare on the Blue Line. She was on her fourth trip when the train crashed.
Turpin said the NTSB plans to look at fatigue and works cycles as part of its report. Several teams have measured and examined the train's cars, as well as CTA tracks, the station architecture plans and the emergency stop system.
This works completes their on-site research, and the cars have been released for removal.
It's not clear how fast the station will reopen.