In the early 1960's, as tourism began to increase in Colorado, the Railway needed additional equipment, but the General Electric Company was not interested in the project. The first units to arrive were Nos. They proved so successful that soon after, the Railway ordered two more nearly identical units, Nos. 16 and 17 . These Swiss railcars are self-contained units, powered by two Cummins diesel engines mounted underneath the seating area. As with the GE locomotives, they are diesel-electric.
Generators driven by the diesel engines provide the power to traction motors for the ascent.
For the descent, the diesel engines are shut down and the traction motors work as generators. The electric power generated is consumed by resistor banks on the roof of the railcars. Bigger units were needed as tourism continued to grow into the 1970's. The Manitou and Pike's Peak Railway officials returned to Swiss Locomotive Works in 1974 with a request for a train which could carry over 200 people . The results were the articulated railcars Nos.