Shinkansen Maintenance Tokai

The , colloquially known in English as the bullet train, is a network of high-speed railway lines in Japan. Initially, it was built to connect distant Japanese regions with Tokyo, the capital, to aid economic growth and development. Beyond long-distance travel, some sections around the largest metropolitan areas are used as a commuter rail network. It is operated by five Japan Railways Group companies.

Over the Shinkansen's 50-plus-year history, carrying over 10 billion passengers, there has been not a single passenger fatality or injury on board due to derailments or collisions.

Starting with the Tokaido Shinkansen () in 1964, the network has expanded to currently consist of of lines with maximum speeds of , of Mini-Shinkansen lines with a maximum speed of , and of spur lines with Shinkansen services. The network presently links most major cities on the islands of Honshu and Kyushu, and Hakodate on northern island of Hokkaido, with an extension to Sapporo under construction and scheduled to commence in March 2031. The maximum operating speed is (on a 387.5 km section of the Tōhoku Shinkansen). Test runs have reached for conventional rail in 1996, and up to a world record for SCMaglev trains in April 2015.

The original Tokaido Shinkansen, connecting Tokyo, Nagoya and Osaka, three of Japan's largest cities, is one of the world's busiest high-speed rail lines. In the one-year period preceding March 2017, it carried 159 million passengers, and since its opening more than five decades ago, it has transported more than 6.4 billion total passengers. At peak times, the line carries up to 16 trains per hour in each direction with 16 cars each (1,323-seat capacity and occasionally additional standing passengers) with a minimum headway of three minutes between trains.

The Shinkansen network of Japan had the highest annual passenger ridership (a maximum of 353 million in 2007) of any high-speed rail network until 2011, when the Chinese high-speed railway network surpassed it at 370 million passengers annually, reaching over 2.3 billion annual passengers in 2019.

Etymology

in Japanese means 'new trunk line' or 'new main line', but this word is used to describe both the railway lines the trains run on and the trains themselves. In English, the trains are also known as the bullet train. The term originates from 1939, and was the initial name given to the Shinkansen project in its earliest planning stages. Furthermore, the name , used exclusively until 1972 for trains on the Tōkaidō Shinkansen, is used today in English-language announcements and signage.

History

Japan was the first country to build dedicated railway lines for high-speed travel. Because of the mountainous terrain, the existing network consisted of narrow-gauge lines, which generally took indirect routes and could not be adapted to higher speeds due to technical limitations of narrow-gauge rail. For example, if a standard-gauge rail has a curve with a maximum speed of , the same curve on narrow-gauge rail will have a maximum allowable speed of . Consequently, Japan had a greater need for new high-speed lines than countries where the existing standard gauge or broad gauge rail system had more upgrade potential.

Among the key people credited with the construction of the first Shinkansen are Hideo Shima, the Chief Engineer, and Shinji Sogō, the first President of Japanese National Railways (JNR) who managed to persuade politicians to back the plan. Other significant people responsible for its technical development were Tadanao Miki, Tadashi Matsudaira, and Hajime Kawanabe based at the Railway Technical Research Institute (RTRI), part of JNR. They were responsible for much of the technical development of the first line, the Tōkaidō Shinkansen. All three had worked on aircraft design during World War II.

Early proposals

The popular English name ''bullet train'' is a literal translation of the Japanese term , a nickname given to the project while it was initially discussed in the 1930s. The name stuck because of the original 0 Series Shinkansen's resemblance to a bullet and its high speed.

The ''Shinkansen'' name was first formally used in 1940 for a proposed standard gauge passenger and freight line between Tokyo and Shimonoseki that would have used steam and electric locomotives with a top speed of . Over the next three years, the Ministry of Railways drew up more ambitious plans to extend the line to Beijing (through a tunnel to Korea) and even Singapore, and build connections to the Trans-Siberian Railway and other trunk lines in Asia. These plans were abandoned in 1943 as Japan's position in World War II worsened. However, some construction did commence on the line; several tunnels on the present-day Shinkansen date to the war-era project.

Construction

Following the end of World War II, high-speed rail was forgotten for several years while traffic of passengers and freight steadily increased on the conventional Tōkaidō Main Line along with the reconstruction of Japanese industry and economy. By the mid-1950s the Tōkaidō Line was operating at full capacity, and the Ministry of Railways decided to revisit the Shinkansen project. In 1957, Odakyu Electric Railway introduced its 3000 series SE Romancecar train, setting a world speed record of for a narrow gauge train. This train gave designers the confidence that they could safely build an even faster standard gauge train. Thus the first Shinkansen, the 0 series, was built on the success of the Romancecar.

In the 1950s, the Japanese national attitude was that railways would soon be outdated and replaced by air travel and highways as in the United States and many countries in Europe. However, Shinji Sogō, President of Japanese National Railways, insisted strongly on the possibility of high-speed rail, and the Shinkansen project was implemented.

Government approval came in December 1958, and construction of the first segment of the Tōkaidō Shinkansen between Tokyo and Osaka started in April 1959. The cost of constructing the Shinkansen was at first estimated at nearly 200 billion yen, which was raised in the form of a government loan, railway bonds and a low-interest loan of US$80 million from the World Bank. Initial estimates, however, were deliberately understated and the actual cost was about 400 billion yen. As the budget shortfall became clear in 1963, Sogo resigned to take responsibility.

A test facility for rolling stock, now part of the line, opened in Odawara in 1962.

Initial success

The Tōkaidō Shinkansen began service on 1 October 1964, in time for the first Tokyo Olympics. The conventional Limited Express service took six hours and 40 minutes from Tokyo to Osaka, but the Shinkansen made the trip in just four hours, shortened to three hours and ten minutes by 1965. It enabled day trips between Tokyo and Osaka, the two largest metropolises in Japan, significantly changed the style of business and life of the Japanese people, and increased new traffic demand. The service was an immediate success, reaching the 100 million passenger mark in less than three years on 13 July 1967, and one billion passengers in 1976. Sixteen-car trains were introduced for Expo '70 in Osaka. With an average of 23,000 passengers per hour in each direction in 1992, the Tōkaidō Shinkansen was the world's busiest high-speed rail line. As of 2014, the train's 50th anniversary, daily passenger traffic rose to 391,000 which, spread over its 18-hour schedule, represented an average of just under 22,000 passengers per hour.

The first Shinkansen trains, the 0 series, ran at speeds of up to , later increased to . The last of these trains, with their classic bullet-nosed appearance, were retired on 30 November 2008. A driving car from one of the 0 series trains was donated by JR West to the National Railway Museum in York, United Kingdom in 2001.

Network expansion

The Tōkaidō Shinkansen's rapid success prompted an extension westward to Okayama, Hiroshima and Fukuoka (the San'yō Shinkansen), which was completed in 1975. Prime Minister Kakuei Tanaka was an ardent supporter of the Shinkansen, and his government proposed an extensive network paralleling most existing trunk lines. Two new lines, the Tōhoku Shinkansen and Jōetsu Shinkansen, were built following this plan. Many other planned lines were delayed or scrapped entirely as JNR slid into debt throughout the late 1970s, largely because of the high cost of building the Shinkansen network. By the early 1980s, the company was practically insolvent, leading to its privatization in 1987.

Development of the Shinkansen by the privatised regional JR companies has continued, with new train models developed, each generally with its own distinctive appearance (such as the 500 series introduced by JR West). Since 2014, Shinkansen trains run regularly at speeds up to on the Tōhoku Shinkansen, only the Shanghai maglev train and China Railway High-speed networks have commercial services that operate faster.

Since 1970, development has also been underway for the Chūō Shinkansen, a planned maglev line from Tokyo to Osaka. On 21 April 2015, a seven-car L0 series maglev trainset set a world speed record of .

Technology

To enable high-speed operation, Shinkansen uses a range of advanced technology compared with conventional rail, achieving not only high speed but also a high standard of safety and comfort. Its success has influenced other railways in the world, demonstrating the importance and advantages of high-speed rail.

Routing

Shinkansen routes are completely separate from conventional rail lines (except Mini-shinkansen which goes through to conventional lines). Consequently, the shinkansen is not affected by slower local or freight trains (except for Hokkaido Shinkansen while traveling through the Seikan Tunnel), and has the capacity to operate many high-speed trains punctually. The lines have been built without road crossings at grade. Tracks are strictly off-limits with penalties against trespassing strictly regulated by law. The routes use tunnels and viaducts to go through and over obstacles rather than around them, with a minimum curve radius of 4,000 meters (2,500 meters on the oldest Tōkaidō Shinkansen).

Track

The Shinkansen uses standard gauge in contrast to the narrow gauge of older lines. Continuous welded rail and swingnose crossing points are employed, eliminating gaps at turnouts and crossings. Long rails are used, joined by expansion joints to minimize gauge fluctuation due to thermal elongation and shrinkage.

A combination of ballasted and slab track is used, with slab track exclusively employed on concrete bed sections such as viaducts and tunnels. Slab track is significantly more cost-effective in tunnel sections, since the lower track height reduces the cross-sectional area of the tunnel, reducing construction costs up to 30%.
However, the smaller diameter of Shinkansen tunnels, compared to some other high-speed lines, has resulted in the issue of tunnel boom becoming a concern for residents living close to tunnel portals.

The slab track consists of rails, fasteners and track slabs with a cement asphalt mortar. On the roadbed and in tunnels, circular upstands, measuring 400–520 mm in diameter and 200 mm high, are located at 5-metre intervals. The prefabricated upstands are made of either reinforced concrete or pre-stressed reinforced concrete; they prevent the track slab from moving latitudinally or longitudinally. One track slab weighs approximately 5 tons and is 2220–2340 mm wide, 4900–4950 mm long and 160–200 mm thick.

Signal system

The Shinkansen employs an ATC (Automatic Train Control) system, eliminating the need for trackside signals. It uses a comprehensive system of Automatic Train Protection. Centralized traffic control manages all train operations, and all tasks relating to train movement, track, station and schedule are networked and computerized.

Electrical systems

Shinkansen uses a 25 kV AC overhead power supply (20 kV AC on Mini-shinkansen lines), to overcome the limitations of the 1,500 V direct current used on the existing electrified narrow-gauge system. Power is distributed along the train's axles to reduce the heavy axle loads under single power cars. The AC frequency of the power supply for the Tokaido Shinkansen is 60 Hz.

Trains

Shinkansen trains are electric multiple units, offering fast acceleration, deceleration and reduced damage to the track because of the use of lighter vehicles compared to locomotives or power cars. The coaches are air-sealed to ensure stable air pressure when entering tunnels at high speed.

Traction

The Shinkansen has used the electric multiple unit configuration from the outset, with the 0 Series Shinkansen having all axles powered. Other railway manufacturers were traditionally reluctant or unable to use distributed traction configurations (Talgo, the German ICE 2 and the French (and subsequently South Korean) TGV (and KTX-I and KTX-II) use the locomotive (also known as power car) configuration with the AVE Class 102 and continues with it for the Talgo AVRIL because it is not possible to use powered bogies as part of Talgo's bogie design, which uses a modified Jacobs bogie with a single axle instead of two and allows the wheels to rotate independently of each other, on the ICE 2, TGV and KTX it is because it easily allows for a high ride quality and less electrical equipment.) In Japan, significant engineering desirability exists for the electric multiple unit configuration. A greater proportion of motored axles permits higher acceleration, so the Shinkansen does not lose as much time if stopping frequently. Shinkansen lines have more stops in proportion to their lengths than high-speed lines elsewhere in the world.

Lines

The main Shinkansen lines are:

In practice, the Tokaido, San'yō, and Kyushu lines form a contiguous west/southbound line from Tokyo, as train services run between the Tokaido and San'yō lines and between the San'yō and Kyushu lines, though the lines are operated by different companies.

The Tokaido Shinkansen tracks are not physically connected to the lines of the Tohoku Shinkansen at Tokyo Station, as they are operated by separate companies and have separate platforms. Therefore, there is no through service between those lines. All northbound services from Tokyo travel along the Tohoku Shinkansen until at least Ōmiya.

Two further lines, known as '' Mini-shinkansen'', have also been constructed by re-gauging and upgrading existing sections of line:
* Yamagata Shinkansen (Fukushima – Shinjō)
* Akita Shinkansen (Morioka – Akita)

There are two standard-gauge lines not technically classified as Shinkansen lines but run Shinkansen trains as they use tracks leading to Shinkansen storage/maintenance yards:
* Hakata Minami Line ( Hakata – Hakata-Minami)
* Gala-Yuzawa Line – technically a branch of the Jōetsu Line – ( Echigo-Yuzawa – Gala-Yuzawa)

Lines under construction

The following lines are under construction. These lines except Chuo Shinkansen, called or ''planned Shinkansen'', are the Shinkansen projects designated in the Basic Plan decided by the government.

* Hokuriku Shinkansen extension from Kanazawa to Tsuruga is under construction and is scheduled to open in fiscal 2022. Between Hakusan Depot near Kanazawa and Tsuruga, the Shinkansen station was constructed in conjunction with the rebuilding of the adjoining conventional (narrow gauge) line station in anticipation of construction of the line to Osaka.
* Hokkaido Shinkansen from to is under construction and scheduled to open by March 2031.
* Chuo Shinkansen (Tokyo–Nagoya–Osaka) is a planned maglev line. JR Central has announced a 2027 target date for the line from Tokyo to Nagoya. Construction of the project commenced in 2014.

Planned lines

* The extension of Hokuriku Shinkansen to Osaka is proposed, with the route via Obama and Kyoto selected by the government on 20 December 2016. Construction is proposed to commence in 2030, and take 15 years.
* Nishi Kyushu Shinkansen has been built to full Shinkansen standards between Takeo Onsen and Nagasaki, with the existing narrow-gauge line from Shin-Tosu to Takeo Onsen to remain as narrow-gauge track, although there is a proposal to build the section between Shin-Tosu and Takeo Onsen to full Shinkansen standards. In 2018, the Ministry of Land, Infrastructure, Transport and Tourism released cost-benefit analysis results to compare and contrast full Shinkansen, mini-Shinkansen, and Gauge Change Train for this section.
* The extension of Chuo Shinkansen to Osaka is proposed to open in 2037.

Cancelled line

The Narita Shinkansen project to connect Tokyo to Narita International Airport, initiated in the 1970s but halted in 1983 after landowner protests, has been officially cancelled and removed from the Basic Plan governing Shinkansen construction. Parts of its planned right-of-way were used by the Narita Sky Access Line which opened in 2010, and the Keiyo Line reused space originally set aside for the Narita Shinkansen terminus at Tokyo Station. Although the Sky Access Line uses standard-gauge track, it was not built to Shinkansen specifications and there are no plans to convert it into a full Shinkansen line.

Proposed lines

Many Shinkansen lines were proposed during the boom of the early 1970s but have yet to be constructed and have subsequently been shelved indefinitely.
* Hokkaido Shinkansen northward extension: Sapporo–Asahikawa
* : Oshamanbe–Muroran–Sapporo
* : Toyama–Niigata–Aomori
** Toyama–Jōetsu-Myōkō exists as part of the Hokuriku Shinkansen, and Nagaoka–Niigata exists as part of the Jōetsu Shinkansen, with provisions for the Uetsu Shinkansen at Nagaoka.
* : Fukushima–Yamagata–Akita
** Fukushima–Shinjō and Ōmagari–Akita exist as the Yamagata Shinkansen and Akita Shinkansen, respectively, but as "Mini-Shinkansen" upgrades of existing track, they do not meet the requirements of the Basic Plan.
* : Nagoya–Tsuruga
* : Osaka– Oita in 2018 that found the route to be potentially profitable
* : Fukuoka–Ōita–Miyazaki–Kagoshima
* : Ōita–Kumamoto

In addition, the Basic Plan specified that the Jōetsu Shinkansen should start from Shinjuku Station">Shinjuku