CHICAGO (AP) - An operator of a Chicago public-transit train that jumped the tracks and scaled an escalator at one of nation's busiest airports Monday may have dozed off, the president of a Chicago transit union said.
The woman said she had worked extensive overtime recently and was "extremely tired" at the time of the accident, Amalgamated Transit Union Local 308 President Robert Kelly told a news conference.
The derailment happened just before 3 a.m. Monday at the end of the Chicago Transit Authority's Blue Line at O'Hare International Airport. The timing of the accident helped avoid an enormous disaster, as the underground Blue Line station is usually packed with travelers. More than 30 people were hurt, but none had life-threatening injuries.
A CTA supervisor and another worker near the top of the escalator said they saw the train enter at a normal rate of speed, about 15 mph, according to Kelly.
"The next thing they heard the sound (of impact) and the yelling and the screaming," he said.
Investigators had not drawn any conclusions about the cause of the accident, National Transportation Safety Board official Tim DePaepe said Monday afternoon, but that were looking into whether faulty brakes, signals or human error were factors.
The train is designed so that if an operator becomes incapacitated and his or her hand slips off the controls, it should come to a stop. Kelly speculated that, upon impact, inertia may have thrown the operator against the hand switch, accelerating it enough to send it catapulting onto the escalator.
The train operator, who has worked for the CTA for about a year, suffered a leg injury and has been released from the hospital. She will be interviewed by investigators today, Kelly said.
Asked by a reporter whether she may have nodded off, Kelly responded, "The indication is there. Yes."
Kelly described the train operator after the accident as distraught, but still able to help passengers.
Jumping the track likely dissipated the forward movement, thus lessening the accident's severity, said Joseph Schwieterman, a transportation expert at DePaul University.
A more abrupt stop would have slammed people more violently into the train's seats and walls, he said.
The injured were treated at area hospitals and released. Chicago Fire Commissioner Jose Santiago said Monday morning that most were able to walk away from the wreck unaided.
CTA spokesman Brian Steele said earlier Monday the train may have been moving too fast as it approached the station and didn't stop at a bumping post - a metal shock absorber at the end of the tracks.