When is a freight car not a freight car? When it’s a truck. The Roadrailer is a unique intermodal vehicle that is both. These highway trailers / railcars have had a long and interesting story.
Many think of intermodal and Roadrailer technology as something relatively new. The Chesapeake and Ohio introduced the first Roadrailers on the rear of passenger trains between Detroit and Grand Rapids in 1955. The short, 29′ vans were coupled to the back of the daily trains and carried mail and other less-than-carload traffic. Compared to today, the operation was as diminutive as the equipment but it paved the way for future developments.
The bi-modal concept went into hibernation for over a decade. In 1981, this very week in fact, a new generation of Roadrailers debuted on the Illinois Central Gulf. Like the earlier cars, the trailers carried their own set of railroad wheels and were connected to each other with drawbars. While this arrangement reduced tare weight on the rails vs. a traditional trailer-on-flatcar, on the highway the added weight was a detriment. The mechanics of the equipment were another potential problem as well.
Unlike the original service, these new trailers operated as their own dedicated train. After the Illinois Central, several additional railroads experimented with the concept and equipment through the 1980s. They could even be seen running behind EMD F units on CSX. Although the concept was gaining ground, the limitations of the equipment prevented most of the railroads from going forward with the experiment.
Technology Takes Hold
By the end of the decade, the Roadrailer would mature and begin to shed its railroad wheels. Wabash National, the leading builder of trailers in the U.S., purchased the technology in 1991 and redesigned the roadrailer to be much more like a conventional trailer. The noticeable difference between a Roadrailer and a road-only trailer are the extra connection pins and an air line for the train airbrakes.
The trailers are attached to railroad bogies, or trucks, in the terminal. A pneumatic suspension system on the trailer raises the body to accept the bogie. Once attached, the road wheels are then drawn up for clearance. Trains are built from the back to the front, one trailer at a time, with a single bogie supporting both the front of one trailer and the rear of another.
Once the trailers are connected, the air lines must be connected to the bogies which also hold the brake cylinders. An end-of-train device is put on the rear and a special adapter bogie with a standard knuckle coupler at one end is placed under the front of the first trailer.
Because of the tight connections between the trailers, a train of as many as 125 cars has only six inches of coupler slack. With its light weight and tight connections, a Roadrailer handles much more differently than a conventional train. While in some ways this handling is easier and more advantageous, engineers must still be careful as the structure of the trailers is not nearly as robust as a railcar. A sudden stop or start can tear a trailer in half or crush it like a soda can.
The Modern Era
Thanks to these improvements, Roadrailers saw an explosion of growth in the 1990s. The largest operator then and now is Triple Crown Corporation, owned by Norfolk Southern. Conrail bought a 50% stake in the company in 1993 which returned to NS during the merger in 1999.
There were several more operations springing up across the country. Santa Fe tested five trailers specially adapted for hauling automobiles. Later BNSF ordered a large fleet of refrigerated trailers for service out of the Northwest. Canadian National and trucking companies Schneider National, Clipper and Swift also bought fleets of Roadrailers.
Then the technology came full circle as Amtrak purchased new Roadrailers for mail and express shipments. These rode on the rear of passenger trains all across the country.
The golden years were short lived however. Amtrak soon decided that the added delays to passengers more than offset the financial gains from its Roadrailers and other express contracts. All of the other operations except for Triple Crown also fizzled within a few months or years of inception. Many of these Roadrailers were sold to Triple Crown and are still in service. Others can still be spotted riding conventional intermodal trains as trailers.
Triple Crown continues to operate an extensive network across the northeast U.S. serving many automotive suppliers and other industries with the flexible service. In recent months however the company has begun to show a shift to conventional trailers and rumors abound that within a few years it too may cease Roadrailer operations. Just in case, get out there are see them while you can! Who knows if or when the revolution will begin again.