The Japanese Bullet Train: Shinkansen
The history of the Shinkansen starts with the introduction of European rail technology and the first Japanese railway line opened in 1872 connecting Shinbashi (Tokyo) and Yokohama (Kanagawa Prefecture). A key point in this historical event is the use of 1,067 mm narrow-gauge rails for the construction of the line, a suggestion made by British engineers who thought that closer rails would be more suitable considering Japan’s largely steep terrain.
Comparison of (1,435 mm) standard gauge (blue) and (1,067 mm) (red) width. ©Wikiwand
In the early twentieth century, the Japanese government invested huge capital in the railway's infrastructure, and attempts from the railroad authorities to switch to a 1,435 mm wide-gauge rail to have faster trains failed. One of the projects promoted by the Japanese Government railways was the dangan ressha (bullet train 弾丸列車) from 1939, which was supposed to boost the transportation capabilities of the Tōkaidō and San’yō Lines by switching to wide-gauge tracks that would have allowed speeds of up to 160 km/h, connecting Tokyo and Shimonoseki in Yamaguchi Prefecture in nine hours.
After Japan surrendered in 1945, the attempts to reconstruct the economy included again the bullet train project, now called Shinkansen, incorporating in this way the unfinished tunnels and the partially-constructed route from the previous dangan ressha. To make this possible, it was necessary to fund the project and in 1958 JNR, the Japanese National Railways, tried to cover the cost of constructions estimated at nearly ¥200 billion through a government loan, railways bonds, and a low-interest loan of US $80 million from the World Bank. Although the actual cost reached ¥380 billion, in April 1959 the construction of the Tōkaidō Shinkansen began, and it was completed in 1964 just in time for the Tokyo Olympics.
Tōkaidō refers to the ancient land route between Edo and Kyōto, while Shinkansen is used to distinguish new standard gauge (1,435 mm) from the old narrow-gauge (1,067 mm) railways built in Japan since the first link between the capital and Yokohama in 1872. Although Shinkansen (新幹線) means 'new trunk line', nowadays, it refers both to the railway lines the trains run on and the trains themselves.
In comparison to the conventional Limited Express service, which took six hours and forty minutes from Tokyo to Osaka, the Shinkansen shortened this time to three hours and ten minutes by 1965. This changed completely the style of business and life of the Japanese people, allowing them to make day trips within the two big metropolises of Osaka and Tokyo.
While speed was its massive advantage, the Shinkansen also had a small problem: the noise. As the Shinkansen extended and reached new areas, for example, Okayama in 1972 and Hakata in 1975, the issues of noise and vibrations caused by passing trains began to bother people living in urban areas. New measures like inspections and overhauls of tracks were implemented between 1974 and 1982 to prevent further problems, nevertheless, the noise problem persisted. The residents living along the tracks complained in court and reached an agreement with the Japan National Railway in 1986, winning the suit. They made the company construct barriers to reduce the noise pollution as well as improve the design of the trains.
The sonic boom, made by the Shinkansen. ©Vox
It is important to remember that the bullet train reached 240 km/h causing atmospheric pressure waves in front of the train as it passed through tunnels forming a sonic boom at the exit. This sound covered a distance of 400 meters. And there were many tunnels located near highly populated villages the Shinkansen ran through. For this reason the engineers needed to rethink the Shinkansen’s design without decreasing its performance, speed, and use of energy. The aim was to create a faster train that could solve the noise pollution problem.
A part of this team was Eiji Nakatsu, the general manager of the technical development of the Shinkansen, who realized that the sonic boom was caused by a sudden change in air resistance. Besides being an engineer, Nakatsu was also a bird watcher and active member of the Wild Bird Society of Japan. Inspired by the kingfisher he proposed to implement a new concept into the Shinkansen’s design. Such an approach is called biomimicry – creating solutions to human challenges by emulating designs and ideas found in nature. The kingfisher can dive into water at 40 km/h to hunt the prey while making a minimal splash thanks to its streamlined beak which is a long, pointed, wedge-shaped beak.
The world is poorly designed. But copying nature helps. ©Vox (09.11.2017)
After running different tests, using different bullet shapes, and measuring the pressure waves created by shooting them into a pipe, the results confirmed that the ideal Shinkansen’s head shape would resemble that of the kingfisher’s beak. The team of engineers introduced a new design obtaining unexpected results: reduction of noise, elimination of tunnel booms as well as the speed increase of 10% by using 15% less electricity in comparison to the previous trains.
This new design did not only influence daily life, tourism, as well as business in Japan, but it prompted again the use of railways, which were in decline in many countries because of the development of highways and airplane travel. After seeing the Shinkansen’s success, many countries invested again in high-speed train technology, for example the TGV train in France or the Inter-City Express in Germany. In Asia, Japan Rail companies exported their technologies such as the specialized track and safety control system to countries like China and Taiwan.
For the railway’s history, the Shinkansen represented a great success since it serviced 100 million passengers by July 1967 and one billion in 1976. Moreover, in 1992 the Shinkansen became the busiest bullet train in the world with 23,000 passengers in an hour.
As it was mentioned before, the Shinkansen also influenced Japanese tourism. Each year many tourists try this transport not only to move faster from one city to another but also to experience the bullet train, which is the most tranquil, efficient, pleasurable and cost-effective way to get around the country. So, the next time you jump into the Shinkansen, don’t forget to bring your bento box to enjoy the travel ;).
Written by Manuel José Flores Aguilar