1977 Chicago Loop derailment
| Industry | Public transportation |
|---|---|
| Founded | 1947 |
| Headquarters | Chicago , United States |
Area served | Chicago metropolitan area |
| Products | Rapid transit services |
The 1977 Chicago Loop derailment took place on February 4, 1977, when an elevated train operated by the Chicago Transit Authority collided from behind with another train at the northeast corner of the Loop, specifically at Wabash Avenue and Lake Street, during the evening rush period. This impact caused the leading four cars of the rear train to derail and plunge off the elevated tracks onto the street below, resulting in 11 fatalities and injuring more than 180 individuals.
Infrastructure layout
The term "The Loop" designates both Chicago's downtown commercial district and the rectangular route formed by the city's elevated train system. Certain trains complete a full circuit around this Loop, navigating all four corners before resuming their original routes. Others traverse only two corners before diverging onto different tracks. Additionally, some lines operate in a clockwise direction, while others run counter-clockwise.
During 1977, four distinct lines served the Loop, each operating in specific directions. The Ravenswood Line (currently known as the Brown Line) traveled counter-clockwise on the outer track. The Evanston Express (now called the Purple Line) and the Loop Shuttle moved clockwise along the inner track. The Lake–Dan Ryan Line (presently portions of the Green Line and Red Line) operated bidirectionally but only on the Lake and Wabash segments.
On the day of the incident, a malfunction with a track switch compelled dispatchers to reroute the Evanston Express to run counter-clockwise rather than its usual clockwise path. This change placed it on tracks typically used by Ravenswood and westbound Lake–Dan Ryan trains, creating congestion. As a result, the Ravenswood train had to halt and wait for clearance from the Evanston Express. The Ravenswood remained stationary when the Lake–Dan Ryan train subsequently arrived and was forced to stop as well.
Collision
Around 5:25 p.m., a Ravenswood train was halted just beyond the northeast curve, waiting for the Evanston Express to clear the platform at State/Lake. At that moment, a Lake–Dan Ryan train failed to stop and struck the rear of the Ravenswood train at an estimated speed of . Passengers described this initial contact as a subtle "quiet thump."
Following impact, motorman Stephan A. Martin continued applying traction power, pushing his trailing cars forward and pressing his train’s front against the stationary Ravenswood train on a sharp right-angle bend. Unable to advance further, stress bent the coupling bar linking the first two cars, causing their connected ends to lift off the rails. Continued propulsion led to jackknifing and derailment of the first three cars—comprising two Budd 2200 units and one Pullman-Standard 2000. The second and third cars toppled onto the street below; meanwhile, the first car came to rest atop a track support beam. The fourth car partially derailed and hung between the track edge and street level. The remaining four cars stayed on track at Randolph/Wabash station.
Investigation and CTA response
Although traces of THC were detected in one urine sample from Martin, investigators could not conclusively determine his level of impairment during operation. The inquiry uncovered that Martin had a history of safety violations, including reading while driving trains and involvement in a prior derailment. He was also known to engage passengers in conversation while operating trains. It is hypothesized that after completing a normal station stop, Martin became distracted and bypassed a restrictive cab signal by departing at less than , too slow to activate automatic safety controls; following this initial collision, either panic or momentum caused him to advance the Cineston controller, leading to derailment.
Martin was dismissed from employment six months after the accident, with official findings attributing full responsibility for the crash to him.
In response, CTA policies were amended to forbid motormen from proceeding past red signals "on sight" without explicit authorization from Control Center personnel. Furthermore, operations shifted so that the Evanston Express utilized inner Loop tracks instead of outer ones. To enhance safety, an iron beam was installed on the elevated structure designed to prevent cars from falling off. The damaged 2200 units numbered 2289-2290 and 2000 units 2043-2044 were deemed beyond repair and scrapped; all other involved rolling stock underwent repairs and reentered service.