Railroads
World War 2 coincided with recent modernization of American rail roads, including the implementation of streamlining which had taken hold in the 1930s, and the introduction of the diesel-electric locomotive. Railroads moved raw materials and finished goods from factories to ports, achieving record levels of freight traffic, and enjoyed a resurgence of passenger traffic at the same time. The railroads also moved huge numbers of troops to and from training camps and interior bases to the coasts for shipment overseas.
During the war the railroads, with the help of the federal government, expanded the system of Centralized Traffic Control which they had begun installing in the late 1920s. CTC gave a single dispatcher control over a segment of the track mainline, known as a block. Control of the block included the operation of all switches and signals. CTC allowed a single track to operate at up to 75% of the efficiency of double track, improving traffic flow and capacity over a given period of time.
Some railroads had already purchased diesel locomotives prior to American entry into the war, but the war years themselves saw the steam locomotive reach its peak of efficiency of operation. Wartime restrictions on materials suspended the construction of new diesel locomotives, and rationing of oil impeded their operation. The more powerful and efficient steam engines, which burned coal, along with the expansion of CTC and other improvements, allowed the railroads during the Second World War to move significantly more freight and passengers than they had during World War I, despite using less track and fewer engines.
The railroads moved coal from the mines to the customers. Iron ore was freighted to the steel mills, and steel was moved from the mills to shipyards and factories across the nation. Tanks, halftracks, Jeeps, and trucks, moved by rail to the nations ports, to be loaded on ships. Fertilizers moved by rail to farm depots, produce and grain to food processors, meat by refrigerated rail cars to meatpackers, and then to distributors. All of America’s massive war production was dependent on the railroads to get where it was needed, when it was needed.
With gasoline and rubber rationing, long trips by automobile were difficult, and the railroads took up the slack by moving record numbers of passengers, on both long and short hauls, throughout the war years. World War 2 was the peak for American railroads, in terms of freight moved and passengers carried, and the industry began a steady decline in the post war years, as long haul trucking and aviation bit into their freight and passenger businesses. But the war would not have been won without them.