Class 403, "Lufthansa Airport Express" The scheduled use of the "Lufthansa Airport Express" between Düsseldorf Main Station and Frankfurt Airport began on March 27, 1982 at the initiative of the German Transportation Ministry. "Flying at elevation zero" through the scenically attractive Rhine Valley quickly developed into a showpiece of integrated transportation. This cooperation between Lufthansa and the German Federal Railroad was soon viewed as a prototype, and it was based on the conviction that the different transportation carriers should cooperate for economic and ecological reasons. In any event it turned out well that the DB at the start of the Eighties had three four-unit class 403 (powered end cars) and class 404 (intermediate cars) powered rail car trains standing around unemployed for the most part. They had been purchased in 1973 for the Intercity system that was purely first class at that time. However, with the introduction of second class in the Intercity system in 1979 they had become unemployed. These 200 km/h / 125 mph fast trains with all wheels powered had soon acquired the nickname "Donald Duck" due to their characteristic shape. Their visual affinity to an airplane was finally realized on these trains starting on March 27, 1982. These trains "flew" off from the Düsseldorf maintenance facility under the flight numbers LH 1001-1008 as the "Airport Express" with four pairs of trains from Frankfurt Airport to Düsseldorf Main Station (from March of 1983 even to Düsseldorf Airport) and back in a contract with Lufthansa with intermediate stops in Cologne-Deutz, Cologne Main Station, and Bonn Main Station. Before that, the trains had undergone a thorough rebuilding at the Bad Cannstatt maintenance facility in accordance with the airline company's specifications. In the process, they exchanged their unique paint scheme in white-red-black for Lufthansa's product colors of melon yellow / light gray. The goal was to keep from having to increase the uneconomic flight service on the extremely short routes of Cologne/Bonn – Frankfurt and Düsseldorf – Frankfurt. This goal was reached in full. In 1991 for example, more than 218,000 passengers used the "train to the plane" between Düsseldorf and Frankfurt. Had it been necessary to accommodate all of these passengers in Boeing 737 airplanes, it would have meant around 3,000 additional flights. Despite low operating costs (lower than comparable flights on short routes) and relatively high passenger counts, the Lufthansa Airport Express was cancelled on May 23, 1993. One reason was the considerable corrosion damage on the 403 powered rail cars that would have required extensive, costly repairs.