Railroads of the 1990s

Double-stack Railroads

Two of the most exciting technological developments have come with the introduction of double-stack containers and RoadRailers. Double-stacks rely on a flatcar with a sunken floor that allows two intermodal containers to rest one atop the other, doubling the capacity of a flatcar. Southern Pacific was the first major railroad to build these cars, in conjunction with ACF Industries.

Double-stack containers often arrive by ship, then continue their journey by train, with final delivery by truck. Double-stack trains have necessitated the rebuilding of many routes on the nation's mainline railroads to accommodate these ultra-high loads. The clearance of bridges and tunnels were raised in Pennsylvania in a multimillion-dollar project to get double-stack service to the port of Philadelphia. In Virginia, Norfolk Southern eliminated or renovated several tunnels on its hilly line into West Virginia to allow double-stacks to pass between Chicago and the port of Norfolk.

Double-stacks have won back much of the profitable perishable-goods business for the railroads. Replacing the traditional refrigerated boxcar is the 40-foot-long double-stack container, powered by a generator with an automatic backup in case the main generator fails. With double-stack trains running between Seattle and New York in only five days, everything from Alaskan king crab to photographic film can be shipped in temperature-controlled boxes.

In 1977, according to data from the Association of American Railroads, railroads carried only 0.2 percent of produce shipments. After deregulation, perishable traffic jumped to 15 percent. A container, which can make several trips in one month's time, easily outperforms refrigerated boxcars, which by comparison average only one trip a month.

On other railroads, particularly Norfolk Southern, RoadRailers are the current rage. Basically a truck trailer that can ride the rails or the highways, these lightweight, versatile containers operate in dedicated trains of 100 cars or more, moving everything from beer to cat litter. Detachable rail wheels make them easy to put on the tracks, while retractable wheels make them easy to put on the road. Both have meant big gains in productivity.

The railroads redesigned everything. They built new hopper cars to carry the nation's coal for electric power plants, switching to lighter and more durable aluminium designs, and they revamped the traditional wood-hauling car to make it easier to load and unload. They even replaced the wooden tie and spike with concrete ties and metal clamps.

Communications technology has also revolutionized some aspects of railroading. Throughout the industry's history, train crews have left their terminals with a manifest of pre-assigned duties, pickups, and set-offs. On the Union Pacific, the railroad started using a direct-link computer system between the crews and the marketing department. That means reporting immediately when cars are distributed or collected. It also means flexibility in sending service orders to a train on the road.

In Roanoke, Virginia, Norfolk Southern's giant freight yard resembles a big remote-controlled model railroad. Computers set the brakes on the cars being sorted in the railroad's hump yard. They also align the switches. Operators sitting in a strategically positioned tower even manipulate the pace of locomotives shoving cars through the yard.

New freight-car wheel designs have reduced the number of accidents resulting from wheel failure by 80 percent. By changing the shape of the wheel and subjecting the steel to heat treatment, professional engineers have literally reinvented the railroad wheel.