20 February 2009
The invention: An ultrafast passenger railroad system capable of moving passengers at speeds double or triple those of ordinary trains. The people behind the invention: Ikeda Hayato (1899-1965), Japanese prime minister from 1960 to 1964, who pushed for the expansion of public expenditures Shinji Sogo (1901-1971), the president of the Japanese National Railways, the “father of the bullet train” Building a Faster Train By 1900, Japan had a world-class railway system, a logical result of the country’s dense population and the needs of its modernizing economy. After 1907, the government controlled the system through the Japanese National Railways (JNR). In 1938, JNR engineers first suggested the idea of a train that would travel 125 miles per hour from Tokyo to the southern city of Shimonoseki. Construction of a rapid train began in 1940 but was soon stopped because of World War II. The 311-mile railway between Tokyo and Osaka, the Tokaido Line, has always been the major line in Japan. By 1957, a business express along the line operated at an average speed of 57 miles per hour, but the double-track line was rapidly reaching its transport capacity. The JNR established two investigative committees to explore alternative solutions. In 1958, the second committee recommended the construction of a high-speed railroad on a separate double track, to be completed in time for the Tokyo Olympics of 1964. The Railway Technical Institute of the JNR concluded that it was feasible to design a line that would operate at an average speed of about 130 miles per hour, cutting time for travel between Tokyo and Osaka from six hours to three hours. By 1962, about 17 miles of the proposed line were completed for test purposes. During the next two years, prototype trains were tested to correct flaws and make improvements in the design. The entire project was completed on schedule in July, 1964, with total construction costs of more than $1 billion, double the original estimates. The Speeding Bullet Service on the Shinkansen, or New Trunk Line, began on October 1, 1964, ten days before the opening of the Olympic Games. Commonly called the “bullet train” because of its shape and speed, the Shinkansen was an instant success with the public, both in Japan and abroad. As promised, the time required to travel between Tokyo and Osaka was cut in half. Initially, the system provided daily services of sixty trains consisting of twelve cars each, but the number of scheduled trains was almost doubled by the end of the year. The Shinkansen was able to operate at its unprecedented speed because it was designed and operated as an integrated system, making use of countless technological and scientific developments. Tracks followed the standard gauge of 56.5 inches, rather than the more narrow gauge common in Japan. For extra strength, heavy welded rails were attached directly onto reinforced concrete slabs. The minimum radius of a curve was 8,200 feet, except where sharper curves were mandated by topography. In many ways similar to modern airplanes, the railway cars were made airtight in order to prevent ear discomfort caused by changes in pressure when trains enter tunnels. The Shinkansen trains were powered by electric traction motors, with four 185-kilowatt motors on each car—one motor attached to each axle. This design had several advantages: It provided an even distribution of axle load for reducing strain on the tracks; it allowed the application of dynamic brakes (where the motor was used for braking) on all axles; and it prevented the failure of one or two units from interrupting operation of the entire train. The 25,000-volt electrical current was carried by trolley wire to the cars, where it was rectified into a pulsating current to drive the motors. The Shinkansen system established a casualty-free record because of its maintenance policies combined with its computerized Centralized Traffic Control system. The control room at Tokyo Station was designed to maintain timely information about the location of all trains and the condition of all routes. Although train operators had some discretion in determining speed, automatic brakes also operated to ensure a safe distance between trains. At least once each month, cars were thoroughly inspected; every ten days, an inspection train examined the conditions of tracks, communication equipment, and electrical systems. Impact Public usage of the Tokyo-Osaka bullet train increased steadily because of the system’s high speed, comfort, punctuality, and superb safety record. Businesspeople were especially happy that the rapid service allowed them to make the round-trip without the necessity of an overnight stay, and continuing modernization soon allowed nonstop trains to make a one-way trip in two and one-half hours, requiring speeds of 160 miles per hour in some stretches. By the early 1970’s, the line was transporting a daily average of 339,000 passengers in 240 trains, meaning that a train departed from Tokyo about every ten minutes The popularity of the Shinkansen system quickly resulted in demands for its extension into other densely populated regions. In 1972, a 100-mile stretch between Osaka and Okayama was opened for service. By 1975, the line was further extended to Hakata on the island of Kyushu, passing through the Kammon undersea tunnel. The cost of this 244-mile stretch was almost $2.5 billion. In 1982, lines were completed from Tokyo to Niigata and from Tokyo to Morioka. By 1993, the system had grown to 1,134 miles of track. Since high usage made the system extremely profitable, the sale of the JNR to private companies in 1987 did not appear to produce adverse consequences. The economic success of the Shinkansen had a revolutionary effect on thinking about the possibilities of modern rail transportation, leading one authority to conclude that the line acted as “a savior of the declining railroad industry.” Several other industrial countries were stimulated to undertake large-scale railway projects; France, especially, followed Japan’s example by constructing highspeed electric railroads from Paris to Nice and to Lyon. By the mid- 1980’s, there were experiments with high-speed trains based on magnetic levitation and other radical innovations, but it was not clear whether such designs would be able to compete with the Shinkansen model.