Chicago was the first U.S. city to adopt One Person Train Operation.

At 2:43 a.m. on March 24, 2014, a speeding CTA train crashed into the O’Hare airport terminal and went up an escalator. Thirty people were injured.

The “very fatigued” Operator had fallen asleep at the controls.

The emergency braking system failed. There was no Conductor to stop the train; CTA had eliminated them in 1993, saving $3.8 million a year. The costs of the crash exceeded $30 million.