General Motors Electro-Motive Division demonstrator No. 511 on test for the Chicago, Burlington and Quincy Railroad hauling a four-car

Denver Zephyr (2nd section). Photographed near McCook, Nebraska, August 1, 1937 by Otto Perry.

(Fair Use, Rational: Used within EMD 1800 hp B-B and other articles which discuss this particular locomotive.)



The two EMC demonstrators, numbered 511 and 512, were built in August 1935 to demonstrate the future of passenger diesel power to potential customers. The boxy bodywork was not what EMC intended to sell, but it was an easy way to demonstrate the power units and hauling capacity, which would not be changed in the future E-units.

They were demonstrated both together and singly; the latter for shorter trains for local and less busy services, the former to replace larger steam locomotives on heavier trains. These units were highly significant in pioneering multiple unit connections which could be quickly connected and disconnected in the field, allowing units to be "lashed up" into more powerful combinations (operated by a single crew) at will, and allowing malfunctioning units to be replaced with fresh units with ease.

EMC No. 512, painted silver, was added to the ATSF locomotive No. 1 cab/booster pair to help pull the first regular run of the streamlined, Budd Company-built Super Chief on May 18 1937, after the EMC E1 pair 2/2A built for the train burned out some of their traction motors on a record-breaking exhibition run days before.

In 1938, having outlived their usefulness, the two demonstrators were scrapped. Trucks and some other components were re-used for the two EMC NW4 switchers built for the Missouri Pacific Railroad.