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- 14 - from the cars by rescue personnel through doors, windows, or openings made in the car bodies. Most passengers were transported quickly to hospitals by rescue vehicles. The lights went off in three of the cars that fell from the structure. The lights remained lighted in the rear five cars.

Tests and Research

Immediately following the accident, the trackside signal system was tested and no descrepancies were found. The motormen on the Ravenswood and the Lake-Dan Ryan trains, and on the train following the Lake-Dan Ryan train indicated that their cab signals were correct for the block conditions.

The ATC equipment on the first and second units of the Lake-Dan Ryan train was tested and found to be operating properly. The trainphone, which was not connected when found, was tested and found to operate satisfactorily.

The ATC system was tested to determine if under any operating conditions a "yellow 35" or "yellow 15" cab signal aspect could change directly to a flashing red aspect. The steady red aspect was displayed about 4 seconds before it changed to a flashing red and the cab signal would not change directly from a yellow to a flashing red.

Tests of the available brake equipment on the four cars that fell to the street and the brakes of the other four cars on the Lake-Dan Ryan train disclosed that they functioned properly.

About 48 hours after the accident, test trains, similar in consists and appearance to the two involved in the crash, were used to determine visibility factors and stopping distance at the accident site. No obstructions in the operating compartment of the approaching train or in the foreground were found to block the view of the train standing in the curve as the test train moved from Randolph Street Station through the compound curve to the collision point.

In another test the test train was accelerated as rapidly as possible from the eight-car mark at Randolph Street Station until it actuated the overspeed alarm at 15 mph. At that time a full service brake application was made and the train stopped short of the point of impact. The total distance covered was about 118 feet. There was no indication that the stopping capability of the test train was affected by the presence and operation of the flange lubricator.

A mathmetical analysis concluded that, under the best simulation of the prevailing conditions, an impact at 9.5 mph would have caused instability and the overturning of the train. (See appendix B.)