|Chicago & North Western Railway GP35 834 at West Chicago, Illinois on January 29, 1966, Kodachrome by Chuck Zeiler-. Number 834 was built in April 1964 (c/n 28989) was wrecked at Lowden, Iowa on June 20, 1966, retired and traded to EMD. A full report of the accident is available at http://ntl2.specialcollection.net/scripts/ws.dll?file&fn=6&name=S%3A\DOT_56GB\Railroad\WEBSEARCH\4097.PDF
Briefly, GP35 834 was the second of three GP35's (858, 834, 859) dispatched on Train 258 (91 cars plus caboose), following Train 254 (units 862, 849, 1751, 98 cars plus caboose). Train 254 departed Boone Yard late and had switching to do en-route. Train 254's conductor advised the dispatcher of delays as setouts progressed, and the dispatcher ordered Train 254 to cross to the westward main to clear the way for Train 258 to pass. The crossover at Lowden was a trailing point arrangement to the direction of travel and Train 254 was ordered to back through the crossover. As Train 254 was lining up for the crossover, Train 258 was dealing with mechanical issues. The Automatic Train Control system on GP35 858 (Train 258's lead unit) had been acting erratic and when it arrived at Boone Yard around 6:30 PM, a mechanic examined the ATC system, reset the motor generator to the required 75 volts (it had been producing 30 volts resulting intermittent red over yellow displays and automatic brake applications), and he also restored the cutout cock of the brake-valve actuator to cut-in position. Train 258 departed Boone Yard three and a half hours late, and the ATC system again began giving false red over yellow displays and actuating the brakes and the PC switch, which dropped the units to idle. Train speed dropped to 12 mph as the engineer struggled to regain control. Unable to increase speed, he sent the brakeman back to check on the trailing units, where it was discovered the ground relays had tripped on both units. The brakeman reset the ground relays, power was restored, but by that time, the train had come upon another ATC relay point near Nevada, the ATC system gave the false red over yellow display and made an automatic brake application. The engineer then moved the ATC cutout cock to cutout position, and although the ATC system continued to give false red over yellow displays, it could no longer automatically apply the brakes. At 9:37 PM, Train 258 was moving at about 60 mph and approaching Lowden, 20 mph faster than the rules allowed, which restricted the speed to a maximum of 40 mph when any part of the ATC was disabled. The engineer of Train 258 looked back to inspect his train as it entered a curve. Meanwhile Train 254 was preparing to back through the crossover, with the conductor on the caboose and the flagman lining the crossover switches. As Train 258 rounded the curve into Lowden, it became apparent to all that a wreck was imminent, Train 254's rear end crew headed for safety, and Train 258 went into emergency brake application, striking Train 254 at about 30 mph. The caboose and last three cars of Train 254 were destroyed, the lead locomotive of Train 258 overturned, the second (GP35 834) and third units remained upright but at right angles to the track, and the first 17 cars of Train 258 were derailed. There were no human fatalities, but all three locomotives were heavily damaged, ultimately retired and traded back to EMD. The cause was determined to be the failure of the conductor and flagman to provide protection against following trains and the failure of the engineer of Train 258 to operate his train at a restricted speed with part of the ATC disabled.