CHICAGO (CBS) -- Concerns over safety aboard CTA trains remain, days after a Yellow Line train crashed into a snow plow on the tracks in Rogers Park, injuring dozens.
Federal investigators have since determined that the crash was caused by a "design problem" with the braking system on the Yellow Line train.
The question now is what, if any, is the timeline to fix the flaw, which could affect other trains.
The one thing both CTA and National Transportation Safety Board officials wanted to make crystal clear after releasing preliminary findings on the investigation into Thursday's crash is CTA trains are safe to ride.
That's despite the NTSB identifying an apparent design flaw that prevented the train from stopping. What authorities are still are trying to determine is how much of the CTA system might be operating under this problematic design.
On Thursday, a Yellow Line train traveling 26.9 mph crashed into snow equipment on the tracks in Rogers Park. A total of 38 people were injured, including 31 passengers and 7 CTA workers.
Jennifer Homendy, the chair of the National Transportation Safety Board, said the investigation team determined the design problem made it so the braking distance the train had was 1,780 feet, about 1,000 feet shorter than newer systems.
Investigators did not detect any obvious errors on the part of the driver, who was slowing the car at the time of the crash. The CTA knew the equipment was on the track ahead of the train and they were trying to stop.
Homendy stressed the findings she shared on Saturday were preliminary and that more investigation needs to take place. A final analysis will take months to complete.
"The braking distance should have been longer," Homendy said, referring to the CTA's system. "A brand new system today, with the same track, they should have had 2,745 feet to stop that train ... not 1,780 feet. That is a design problem."
She said more modern design systems allow for longer stopping distances, especially as trains have gotten heavier with more passengers.
When CBS 2 inquired with CTA on Sunday about the plan moving forward to fix this apparent "design flaw," a spokesperson would only say that the investigation into Thursday's crash – which is being spearheaded by the NTSB – is still ongoing; not shedding any light on system-wide concerns, or providing a time frame for repairs.
"Really surprising that these tried-and-true older cars have a design specification flow that for years we've been operating with, perhaps, unsafe stopping distances," said Joe Schwieterman, a professor at DePaul University and an expert in the field of transportation. "This, you know, just shows how we constantly need to be vigilant about these new risks, because this was a lot of injury here."
The Yellow Line has been shut down since Thursday's crash. It remained unclear Sunday when the CTA would resume service on the Yellow Line.
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