NBC 5 investigates has more insight into what happened in the moments before the CTA Yellow line train crash and derailment Thursday morning.
NBC 5 obtained audio of the CTA traffic control tower trying to get in contact with a CTA train operator- moments before the derailment that led to 23 individuals being hospitalized and 15 more suffering minor injuries.
The striking thing about this audio is the timing of it. More than an hour before the crash, we hear a warning that a maintenance vehicle will be on the tracks in the area where the collision eventually occurs. Then the audio gets more frantic in the moments before the crash.
At 8:53 am Thursday morning, the CTA control tower alert train operators that there was personnel and equipment on the tracks between Howard and Oakton.
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The next transmission from the control tower is just minutes before the crash around 10:29am. The CTA control tower repeatedly says, “Stop your train please.”
It’s unclear if the train the control tower is referencing is the one that is involved in the crash and derailment.
Moments later, the control tower confirms a crash has occurred between the train and a “snow flat bed train”.
“They have made contact with some equipment at Chicago…which has caused injuries on the train at this time,” said the CTA control tower operator moments after the track.
“Today it looks like we have a worst case scenario where either technology or human error, both happened at the same time,” said Joseph Schwieterman, transportation expert with DePaul University. “This raises the question whether the operator on the other line could have been incapacitated in some way or distracted.”
Worst CTA crashes, derailments in Chicago history
NBC5 Investigates has found that Thursday’s CTA crash on the Yellow Line – which injured approximately 38 people is the most consequential crash involving a CTA train line since February 4, 1977 – nearly 47 years ago – when two CTA “El” trains collided on the elevated Loop tracks at the corner of Wabash and Lake, causing one train to fall completely off the tracks.
Eleven people were killed in that crash and another 180 people were injured, in the worst “El” accident to date.
“We've had derailments as well, they are sort of inevitable when we run a big railroad like this, that may not be attributed to be human error,” said Schwieterman.
Before Thursday’s crash, the second-worst crash occurred on March 24, 2014, when A CTA Blue Line train ran into a post at the O’Hare station, and went up an escalator at the end of the track.
Thirty-four people were injured, including the train operator, and the CTA paid out more than $11 million in damages resulting from that crash.
In that case, the National Transportation Safety Board found that the driver of the train had worked for twelve days in a row, and had dozed off before the crash.
Just a year before, on September 30 2013, an unoccupied “ghost train” – which had been left in a storage yard with its power still on -- rumbled for nearly a mile down the Blue Line tracks and then hit another train full of passengers at the Harlem Station in Forest Park during the Monday morning rush hour. Thirty-three people suffered non-life-threatening injuries.
Another high-profile incident occurred more recently, on September 24, 2019, when a southbound Brown Line train collided with a Purple Line train – also heading southbound -- near the Sedgwick station in Old Town.
There were no injuries, but passengers were removed from the trains, and one person – a diabetic – was taken to a hospital..
The Yellow Line saw it’s last major incident in 2015, when an embankment along the tracks collapsed. The line was out of service for the next five-and-a-half months while CTA engineers repaired it.
The collapse was caused by a Metropolitan Water Reclamation District construction project at a nearby sewage treatment plant. The collapse required the building of a brand new embankment “from scratch,” according to CTA engineers -- which spanned 1200 feet – nearly a quarter-mile.
The reconstructed line was finally re-opened on October 30, 2015, with a big ceremonial ride full of local officials and dignitaries.
“Trains do move in pretty good speeds on the Yellow line, one of the longest stretches with not a lot of stops on the CTA rail system that opened into Howard. the trains get moving pretty quickly. We call it the Skokie swept for reasons designed to be a relatively high speed,” Schwieterman.
NBC 5 Investigates also found roughly nine incidents specific to the Yellow line since 2015- ranging from derailments, vehicle collisions and at least one pedestrian death.
May 18, 2015 – An embankment along the Yellow Line collapsed, cancelling the line’s service for five-and-a-half months while CTA engineers repaired it. The collapse was caused by a Metropolitan Water Reclamation District construction project at a nearby sewage treatment plant. The collapse required the building of a brand new embankment “from scratch,” according to CTA engineers. The reconstructed embankment spanned 1200 feet – nearly a quarter-mile. The line was finally re-opened on October 30, 2015, with a big ceremonial ride full of local officials and dignitaries.
February 11, 2016 – A southbound Yellow Line train derailed near the Dempster station at about 9:30pm. No riders were on board, and no one was injured.
February 23, 2016 – A Yellow Line CTA car derailed, suspending service at about 7:40p. Details aren’t included in the news reports at the time.
April 4, 2016 – A car collided with a CTA Yellow Line train at a grade crossing at East Prairie Road in Skokie, killing one woman in the car, and injuring another passenger in the car. Five passengers from the train were treated at hospitals for “less serious” injuries, according to news reports at the time.
January 6, 2018 – A vehicle collided with a Yellow Line train near Niles Center road in Skokie, sending the train operator and a person in the vehicle to the hospital.
January 1, 2020 – A woman standing on the tracks was hit and killed by a Yellow Line train near the border of Evanston and Skokie.
June 9, 2020 – A Yellow Line train derailed near the Oakton Station at the beginning of the afternoon rush hour, suspending service.
September 17, 2020 – Some kind of medical emergency occurred near the Yellow Line’s Oakton Station, according to news reports, which stopped Yellow Line trains for about an hour.
March 26, 2021 – A teenaged-boy was hit by a CTA Yellow Line train in Evanston, east of Dodge Avenue near the Howard Street station. It’s not clear from news reports what happened to the boy.
CTA did not respond to our questions about the control tower audio, or the collision itself.