took the cue from circuses and started loading their own flatcars in this manner. But, loading even up to six automobiles onto one flat car left a large amount of space above the vehicles that was unused. The natural solution was to take the temporary assemblies that were used to stack and load vehicles within boxcars and permanently attach them to the flatcars. The assemblies, also called racks, created two levels on which automobiles could be loaded. To complete the flatcar, foldaway bridges were added to the ends of the flatcar decks to allow the vehicles to be driven the entire length of a train for loading. Such flatcars eliminated the need for specialized equipment to load and unload boxcar racks. All they needed now was a ramp at the right height. In the mid-1950s, in Germany, Volkswagen Beetle production was increasing beyond the capacity of highway trucks (autocarriers). Volkswagen engineers worked with German railroads to design a railroad car that was basically an extra long version of a vehicle hauling trailer. The design they came up with was able to carry 10 vehicles on one car. VW's two-level flatcar design effectively became the first autorack, entering service circa 1954. Also in 1954, Evans Products, a manufacturer of loading racks for carrying automobiles in conventional boxcars, developed a bi-level Auto-Loader superstructure with an elevating top deck capable of carrying six cars or light trucks on a typical flatcar. Two prototype units were constructed and mounted on conventional flat cars for field testing. NYC 500085 carried a semi-streamlined rack, while UP 5800 had a more utilitarian rack mounted. Neither design went into commercial production. In late 1957, Canadian National (CN) introduced an innovative group of bi-level auto carriers. These CN cars were similar to conventional boxcars, except they had a second floor and doors at both ends of the car instead of the usual side doors. They were huge by the standards of the time; the cars were long and could carry eight vehicles. These cars were a big success and helped lead to the development of today's enclosed auto racks. In 1959, when flat cars capable of carrying two highway trailers in trailer-on-flatcar (TOFC), or "piggyback" service were introduced, new automobiles began to be shipped by rail loaded on highway auto-carrier trailers. Eight to ten autos could be carried per flat car in this manner. By 1960 several U.S. railroads