Prototype History
TOFC or Trailer On FlatCar is one of the most basic forms of intermodal transportation. The concept of loading trailers, or wagons, onto flatcars actually dates to the mid-1800s. The concept was adopted by the circus and military before coming into its own with the rise of commercial trucking in the 1950s.
Several railroads pioneered new TOFC services in the 1950s. The concept allowed trucks to handle the door-to-door deliveries with railroads taking the load for the long haul. Initially, many railroads tried putting small ramps at many towns. Larger "hubs" quickly proved more efficient.
Early operations used "circus style" loading, where trailers were backed onto the flatcars from one end. Special bridge plates were lowered between cars to allow the trucks to cross. This process, originated by the circus operations, was time consuming and challenging with long cuts of cars.
Once in place, trailers had to be secured with chains and wheel chocks. At the destination, the train had to be backed up to the ramp with the trailers facing the ramp so that tractors could attach to unload.
As terminals expanded in the 1960s, cranes and lifts and new fifth-wheel couplings sped loading an unloading operations greatly. These facilities could also often handle shipping containers as well as trailers.
Equipment
Early operations often relied on smaller 40 and 50 foot flatcars to haul trailers. Longer cars designed for TOFC operation were 75 feet. These could haul two standard trailers. TOFC flatcars were usually equipped with drop plates on the ends and places to attach the tie-down chains on the sides and centers. Rubrails along the sides were also sometimes used to prevent a trailer from rolling off during loading.
As trailers grew to 40 foot standard lengths, flatcars also grew to 85 and later 89 feet. The latter were usefull even after 45 foot trailers became common in the 1980s. The rise of 48 and then 53 foot trailers in the 1990s meant that only one could be handled on a typical 89 foot flat. Some have been paired with a drawbar allowing a trailer to span the gap. A variety of hitch arrangements allow different trailer and container combinations.
Spine cars offered reduced length and weight and greater flexibility than flats. By shrinking the platform size, these cars were lighter. Three and five unit articulated cars offered greater efficiency by reducing coupler slack and wheels.
Well cars are normally used for containers, but some have hitches for trailer use as well. This flexibility allows equipment in intermodal pools to carry whatever load is needed.
Trailer Train (TTX)
The high cost and national nature of intermodal markets enticed railroads to pool their resources when purchasing equipment. Trailer Train Corporation was created in 1955 to supply intermodal flatcars to the railroads that invested in it. This shielded the railroads themselves from the investment cost if the new technology failed. It also provided more seemless service across multiple roads and encouraged standardization and cooperation between competing lines.
Renamed TTX Corporation in 1991, the companies yellow flat, spine and well cars are seen in almost every intermodal train. The company also supplies flat cars for autoracks and other uses and is the parent company for the Railbox and Railgon boxcar and gondola pools.
In addition to Trailer Train, many railroads own their own equipment which is often pooled to operate nationally.
