Dieselisation
Dieselisation took place largely because of the tremendous reduction in operating costs it allowed. Steam locomotives require large pools of labour to clean, load, maintain and run. They also require extensive service, coaling and watering facilities. This was their biggest inferior measure as compared to the diesel locomotive in the number of ton-miles or passenger traffic miles either could run. Diesels could and did have a significantly higher initial price per unit-horsepower delivered. However, their far greater range between fueling stops, the absence of water stops, and the much higher unit availability between inspection repair and maintenance stops, were far better than steam. Diesels simply required significantly less time and labour to operate and maintain. Diesel power was also more scalable to power requirements, owing to the control systems that allowed multiple units to be controlled by one operator. "Double header" steam power required a crew for each locomotive. Initially, diesel locomotives were less powerful than the typical steam locomotives. Between the late 1930s and the late 1950s the power available with diesel locomotive engines roughly doubled, although the most powerful steam locomotives ever built still exceeded the power of the most powerful diesel locomotives from the late Twentieth Century.
Lancaster and Chester Railroad
In 1946, the L&C upgraded its fleet by buying six diesel locomotives from the U.S. Army. These 65-ton Whitcomb locomotives had seen service in Italy during the war and burned about the same amount of oil to run that the old steam engines used for lubrication. The purchase of these engines made the L&C the first fully diesel-operated railroad in the state, something that Springs liked to boast of. The steam engines formerly used by the railroad were either sold or put out to pasture. However, these diesels did not spend long on the line as they were replaced by three 70-ton GEs in late 1950. Among the Whitcombs, number 51 passed to the Allegheny and South Side Railway where it would stay until the end of that property.