Editing Shinkansen (section)

== Future ==
=== Speed increases ===
====Tōhoku Shinkansen====
[[E5 Series Shinkansen|E5 series]] trains, capable of up to {{convert|320|km/h|mph|abbr=on|round=5}}, initially limited to {{convert|300|km/h|mph|0|abbr=on}}, were introduced on the [[Tōhoku Shinkansen]] in March 2011. Operation at the maximum speed of {{convert|320|km/h|mph|abbr=on|round=5}} between {{STN|Utsunomiya|x}} and {{STN|Morioka|x}} on this route commenced on 16 March 2013. It reduced the journey time to around 3 hours for trains from Tokyo to Shin-Aomori, a distance of {{convert|674|km|mi|abbr=on}}.

Extensive trials using the [[Fastech 360]] test trains have shown that operation at {{convert|360|km/h|mph|0|abbr=on}} is not feasible because of problems of [[noise pollution]] (particularly [[Piston effect#Tunnel Boom|tunnel boom]]), overhead wire wear, and braking distances. On 30 October 2012, JR East announced that it was pursuing research and development to increase speeds to {{convert|360|km/h|mph|0|abbr=on}} on the Tohoku Shinkansen by 2020.<ref name="jreast20121030">{{cite web|url=http://www.jreast.co.jp/press/2012/20121013.pdf |script-title=ja:グループ経営構想V |trans-title=Group Business Vision V |date=30 October 2012 |publisher=East Japan Railway Company |location=Japan |page=5 |language=ja |archive-url=https://web.archive.org/web/20121202011722/http://www.jreast.co.jp/press/2012/20121013.pdf |archive-date=2 December 2012 |access-date=17 November 2012 }}</ref> The [[ALFA-X]] is undergoing testing.

====Hokkaido Shinkansen====
Upon commencement of services in 2016, the maximum speed on the approximately {{convert|82|km|mi|abbr=on}} [[dual gauge]] section of the [[Hokkaido Shinkansen]] (including through the [[Seikan Tunnel]]) was {{convert|140|km/h|mph|round=5|abbr=on}}, which was increased to {{convert|160|km/h|mph|round=5|abbr=on}} by March 2019.<ref name="saves3mins">{{Cite web |date=31 March 2021 |title=Seikan tunnel Shinkansen speed-up saves 3 min |url=https://www.railwaygazette.com/high-speed/seikan-tunnel-shinkansen-speed-up-saves-3-min/58804.article |url-access=subscription |url-status=live |archive-url=https://web.archive.org/web/20210919081124/https://www.railwaygazette.com/high-speed/seikan-tunnel-shinkansen-speed-up-saves-3-min/58804.article |archive-date=19 September 2021 |access-date=5 March 2022 |website=Railway Gazette International}}</ref> There are approximately 50 freight trains using the dual gauge section each day, so limiting the travel of such trains to times outside of Shinkansen services is not an option. Because of this and other weather-related factors cited by JR East and JR Hokkaido, the fastest journey time between Tokyo and Shin-Hakodate-Hokuto is 3 hours, 57 minutes.

During the 2020-21 New Year Holiday period, certain Shinkansen services were operated at {{convert|210|km/h|mph|round=5|abbr=on}} on the dual gauge section and was proposed again for the [[Golden Week (Japan)|Golden Week]] Holiday period from 3–6 May 2021, due to fewer freight trains operating.<ref name="saves3mins" />
 
To achieve the full benefit of Shinkansen trains travelling on the dual gauge section at {{convert|260|km/h|mph|round=5|abbr=on}} (the maximum speed proposed through the tunnel), alternatives are being considered, such as a system to automatically slow Shinkansen trains to {{convert|200|km/h|mph|round=5|abbr=on}} when passing narrow-gauge trains, and/or loading freight trains onto special "[[Train on Train]]" standard-gauge trains (akin to a covered piggyback flatcar train) built to withstand the [[shock wave]] of oncoming Shinkansen trains traveling at full speed. This would enable a travel time from Tokyo to Shin-Hakodate-Hokuto of 3 hours and 45 minutes, a saving of 12 minutes.

=== Hokuriku extension ===
{{Further|Hokuriku Shinkansen#Future plans}}[[File:Fukui-C-3082.jpg|thumb|Construction of the [[Hokuriku Shinkansen]] in [[Fukui (city)|Fukui]]]]
The Hokuriku Shinkansen was extended from Kanazawa to Tsuruga on 16 March 2024.<ref>{{cite web | url=https://www.railwaygazette.com/high-speed/tsuruga-joined-to-shinkansen-network/66140.article?ID=z9xqh~9jrfnt~q9qqr~W4ik~Ky0gk&utm_campaign=RG-WEEKLY-Hitachi-220324-DE&utm_medium=email&utm_source=email&utm_content=newsletter | title=Tsuruga joined to Shinkansen network }}</ref>

There are further plans to extend the line from Tsuruga to Osaka, with the Obama-Kyoto route chosen by the government on 20 December 2016,<ref name="railwaygazette.com">{{cite web |work=Railway Gazette |title=Hokuriku extension route agreed |url=http://www.railwaygazette.com/news/infrastructure/single-view/view/hokuriku-extension-route-agreed.html |url-access=subscription |url-status=live |archive-url=https://web.archive.org/web/20210516032820/https://www.railwaygazette.com/high-speed/hokuriku-extension-route-agreed/43741.article |archive-date=16 May 2021 |access-date=10 July 2022}}</ref> after a government committee investigated the five nominated routes.<ref name="ReferenceA">{{Cite web |date=15 March 2016 |title=Japan's newest bullet train line has busy first year |url=https://asia.nikkei.com/Politics-Economy/Economy/Japan-s-newest-bullet-train-line-has-busy-first-year |url-status=live |archive-url=https://web.archive.org/web/20220305141940/https://asia.nikkei.com/Politics-Economy/Economy/Japan-s-newest-bullet-train-line-has-busy-first-year |archive-date=5 March 2022 |access-date=5 March 2022 |website=Nikkei}}</ref>

Construction of the extension beyond Tsuruga is not expected to commence before 2030, with a projected 15-year construction period. On 6 March 2017 the government committee announced the chosen route from Kyoto to Shin-Osaka is to be via [[Kyotanabe]], with a station at {{STN|Matsuiyamate|x}} on the [[Katamachi Line]].<ref>{{cite web |last=京都新聞 |title=北陸新幹線新駅「松井山手」検討 京都－新大阪南回り案 |trans-title=Hokuriku Shinkansen new station "Matsui Yamate" study Kyoto-Shin-Osaka southbound plan |url=http://www.kyoto-np.co.jp/top/article/20170307000013 |archive-url=https://web.archive.org/web/20170307023530/http://www.kyoto-np.co.jp/top/article/20170307000013 |archive-date=7 March 2017 |access-date=11 March 2017 |website=Kyoto-np.co.jp |language=ja}}</ref><ref>{{cite web |last=日本テレビ |title=北陸新幹線"京田辺市ルート"最終調整へ |trans-title=To the final adjustment of the Hokuriku Shinkansen "Kyotanabe City Route" |url=http://www.news24.jp/articles/2017/03/06/04355784.html |archive-url=https://web.archive.org/web/20210512121232/https://www.news24.jp/articles/2017/03/06/04355784.html |archive-date=12 May 2021 |access-date=11 July 2022 |website=news24.jp |language=ja}}</ref>

==== Abandoned interim Gauge Change plans ====
To extend the benefits of the Hokuriku Shinkansen to stations west of Tsuruga before the line to Osaka is completed, JR West was working in partnership with Talgo on the development of a [[Gauge Change Train]] (CGT) capable of operating under both the 25&nbsp;kV AC electrification used on the Shinkansen and the 1.5&nbsp;kV DC system employed on conventional lines. A trial of the proposed bogie was undertaken on a purpose-built {{convert|180|m|ft|abbr=on}} gauge-changer at Tsuruga, but it was unsuccessful and the plans were abandoned.<ref>{{cite web |last=Barrow |first=Keith |date=7 August 2015 |title=Talks begin on Hokuriku Shinkansen extension |url=http://www.railjournal.com/index.php/high-speed/talks-begin-on-hokuriku-shinkansen-extension.html?channel=523+*+* |archive-url=https://web.archive.org/web/20170916225223/http://www.railjournal.com/index.php/high-speed/talks-begin-on-hokuriku-shinkansen-extension.html?channel=523+%2A+* |archive-date=16 September 2017 |access-date=11 July 2022 |website=railjournal.com}}</ref>

=== Tohoku extension/Hokkaido Shinkansen ===
The [[Hokkaido Shinkansen]] forms an extension of the Tohoku Shinkansen north of {{STN|Shin-Aomori|x}} to [[Shin-Hakodate-Hokuto Station]] (north of the [[Hokkaido]] city of [[Hakodate]]) through the [[Seikan Tunnel]], which was converted to dual gauge as part of the project, opening in March 2016.

[[JR Hokkaido]] is extending the Hokkaido Shinkansen from Shin-Hakodate-Hokuto to {{STN|Sapporo|x}} to open by 2038. The {{convert|211.3|km|mi||abbr=on}} extension will be approximately 76% in tunnels, including major tunnels such as Toshima (~{{convert|32.675|km|mi||abbr=on}}) Oshima (~{{convert|26.5|km|mi||abbr=on}}), Teine (~{{convert|26.5|km|mi||abbr=on}}) and Shiribeshi (~{{convert|18|km|mi||abbr=on}}).<ref>{{cite web |title=今回の認可対象区間 概要図 |trans-title=Outline map of the section subject to this approval |url=http://www.mlit.go.jp/common/000215188.pdf |archive-url=https://web.archive.org/web/20220709093503/https://www.mlit.go.jp/common/000215188.pdf |archive-date=9 July 2022 |access-date=4 March 2022 |website=mlit.go.jp |language=Ja }}</ref>

Although an extension from Sapporo to [[Asahikawa]] was included in the 1973 list of planned lines, at this time it is unknown whether the Hokkaido Shinkansen will be extended beyond Sapporo.

=== Nishi Kyushu Shinkansen ===
{{Main|Nishi Kyushu Shinkansen}}
[[JR Kyushu]] opened the Nishi Kyushu Shinkansen from {{STN|Takeo-Onsen|x}} to {{STN|Nagasaki|x}} (built to full Shinkansen standard) on 23 September 2022, with the existing narrow-gauge section between Shin-Tosu and Takeo Onsen proposed to be upgraded as part of this project.

This proposal initially involved introducing [[Gauge Change Train]]s (GCT) travelling from Hakata to Shin-Tosu ({{convert|26.3|km|mi|abbr=on}}) on the existing Kyushu Shinkansen line, then passing through a specific gauge changing (standard to narrow) section of track linking to the existing [[Nagasaki Main Line]], along which it would travel to Hizen Yamaguchi ({{convert|37.6|km|mi|abbr=on}}), then onto the [[Sasebo Line]] to Takeo-Onsen ({{convert|13.7|km|mi|abbr=on}}), where another gauge changing section (narrow to standard) would lead onto the final Shinkansen line to Nagasaki ({{convert|66|km|mi|abbr=on}}). However, significant technical issues with the axles of the GCT resulted in its cancellation.

On 28 October 2020, JR Kyushu announced it would utilize a 6-car version of the N700S for the isolated Shinkansen section from Nagasaki, with 'cross platform' change to a relay service at Takeo Onsen station to connect to Hakata.<ref name="ReferenceB">{{Cite web |title=Shorter N700S to serve Nagasaki |url=https://www.railwaygazette.com/high-speed/shorter-n700s-to-serve-nagasaki/57681.article |url-access=subscription |url-status=live |archive-url=https://web.archive.org/web/20210628222520/https://www.railwaygazette.com/high-speed/shorter-n700s-to-serve-nagasaki/57681.article |archive-date=28 June 2021 |access-date=5 March 2022 |website=Railway Gazette International}}</ref> JR Kyushu also announced the service would continue to use the name 'Kamome' for the Hakata-Nagasaki service, which has been in use since 1961.<ref name="kamome_selection">{{cite web |title=2022年度秋頃に西九州新幹線が開業します!列車名「かもめ」 |trans-title=The West Kyushu Shinkansen will open in the fall of 2022! Train name "Kamome" |url=https://www.jrkyushu.co.jp/train/nishikyushu/ |url-status=live |archive-url=https://web.archive.org/web/20220610210357/https://www.jrkyushu.co.jp/train/nishikyushu/ |archive-date=10 June 2022 |access-date=4 August 2021 |website=jrkyushu.co.jp |language=ja}}</ref>

The Shinkansen line shortens the distance between Hakata and Nagasaki by 6.2% ({{convert|9.6|km|mi|abbr=on}}), and while only 64% of the route is built to full Shinkansen standards, it eliminated the slowest sections of the previous narrow-gauge route.

As part of the GCT proposal, the {{convert|12.8|km|mi|abbr=on}} section of single track between Hizen Yamaguchi and Takeo Onsen was proposed to be duplicated. However, due to the issues with the development of the GCT, the proposal did not advance.

The initial section between Nagasaki and Takeo Onsen opened on 23 September 2022.<ref>{{Cite press release |title=九州新幹線の開業日について |date=22 February 2022 |publisher=九州旅客鉄道 |url=https://www.jrkyushu.co.jp/news/__icsFiles/afieldfile/2022/02/22/220222_nishikyushu_kaigyoubi.pdf |language=Japanese |access-date=22 February 2022 |archive-url=https://web.archive.org/web/20220222054752/https://www.jrkyushu.co.jp/news/__icsFiles/afieldfile/2022/02/22/220222_nishikyushu_kaigyoubi.pdf |archive-date=22 February 2022 |trans-title=Opening date of the Nishi Kyusyu Shinkansen}}</ref>

=== Maglev (''Chūō Shinkansen'') ===
[[Maglev]] trains have been undertaking test runs on the Yamanashi test track since 1997, running at speeds of over {{convert|500|km/h|abbr=on}}. As a result of this extensive testing, maglev technology is almost ready for public usage.<ref name="maglev">{{cite web |url=http://english.jr-central.co.jp/company/ir/annualreport/_pdf/annualreport2010-05.pdf |title=Promoting the Tokaido Shinkansen Bypass by the Superconducting Maglev system |publisher=english.jr-central.co.jp |access-date=30 April 2011 |archive-url=https://web.archive.org/web/20110715113749/http://english.jr-central.co.jp/company/ir/annualreport/_pdf/annualreport2010-05.pdf |archive-date=15 July 2011}}</ref> An extension of the test track from {{convert|18.4|to|42.8|km|mi|abbr=on}} was completed in June 2013, enabling extended high-speed running trials to commence in August 2013. This section will be incorporated into the [[Chūō Shinkansen]] which will eventually link Tokyo to Osaka. Construction of the [[Shinagawa, Tokyo|Shinagawa]] to [[Nagoya]] section began in 2014, with 86% of the {{convert|286|km|mi|abbr=on}} route to be in tunnels. Plans were approved in 2017 for the Chūō Shinkansen to begin at [[Tokyo Station]], rather than [[Shinagawa Station]] as initially planned due to difficulties in securing land.<ref>{{Cite web |date=15 November 2019 |title=Chūō Shinkansen: Tokyo to Osaka by Maglev |url=https://www.jrailpass.com/blog/chuo-shinkansen-maglev |access-date=6 July 2023 |website=Japan Rail Pass Travel Blog |language=en}}</ref>

JR Central originally aimed to begin commercial service between Tokyo and Nagoya in 2027. However, in 2024, Central Japan Railway Co President Shunsuke Niwa said that due to construction delays a 2027 opening was now impossible and it is not expected to open until at least 2034.<ref name="auto1" /><ref name="auto" />

Following the shortest route (through the [[Japanese Alps]]), JR Central estimates that it will take 40 minutes to run from Shinagawa to Nagoya. The planned travel time from Shinagawa to Shin-Osaka is 1 hour 7 minutes. The Tokaido Shinkansen {{as of|2010|lc=y}} had a minimum connection time of 2 hours 19 minutes.<ref>{{cite news |date=28 October 2010 |title=Maglev car design unveiled |work=The Japan Times |url=https://www.japantimes.co.jp/news/2010/10/28/business/maglev-car-design-unveiled/ |access-date=11 July 2022 |archive-url=https://web.archive.org/web/20190108044409/https://www.japantimes.co.jp/news/2010/10/28/business/maglev-car-design-unveiled/ |archive-date=8 January 2019}}</ref>

While the government has granted approval<ref>{{cite news |date=16 December 2010 |title=Most direct line for maglev gets panel OK |work=The Japan Times |url=https://www.japantimes.co.jp/news/2010/12/16/business/most-direct-line-for-maglev-gets-panel-ok/ |access-date=16 December 2010 |archive-url=https://web.archive.org/web/20190108043936/https://www.japantimes.co.jp/news/2010/12/16/business/most-direct-line-for-maglev-gets-panel-ok/ |archive-date=8 January 2019}}</ref> for the shortest route between Tokyo and Nagoya, some prefectural governments, particularly Nagano, lobbied to have the line routed farther north to serve the city of [[Chino, Nagano|Chino]] and either [[Ina, Nagano|Ina]] or {{STN|Kiso-Fukushima|x}}. However, that would increase both the travel time (from Tokyo to Nagoya) and the cost of construction.<ref>{{cite news |date=21 October 2008 |title=LDP OKs maglev line selections |work=The Japan Times |url=https://www.japantimes.co.jp/news/2008/10/22/business/ldp-oks-maglev-line-selections/ |access-date=11 July 2022 |archive-url=https://web.archive.org/web/20180107175042/https://www.japantimes.co.jp/news/2008/10/22/business/ldp-oks-maglev-line-selections/ |archive-date=7 January 2018}}</ref> JR Central has confirmed it will construct the line through [[Kanagawa Prefecture]], and terminate at [[Shinagawa Station]].

The route for the Nagoya to Osaka section is also contested. It is planned to go via [[Nara, Nara|Nara]], about {{convert|40|km|mi||abbr=on}} south of [[Kyoto]]. Kyoto is lobbying to have the route moved north and be largely aligned with the existing [[Tokaido Shinkansen]], which services Kyoto and not Nara.<ref>{{cite news |date=3 May 2012 |title=Economy, prestige at stake in Kyoto-Nara maglev battle |work=The Japan Times |url=https://www.japantimes.co.jp/news/2012/05/03/national/economy-prestige-at-stake-in-kyoto-nara-maglev-battle/ |access-date=3 May 2012 |archive-url=https://web.archive.org/web/20190108060652/https://www.japantimes.co.jp/news/2012/05/03/national/economy-prestige-at-stake-in-kyoto-nara-maglev-battle/ |archive-date=8 January 2019}}</ref>

=== Mini-Shinkansen ===
{{Nihongo|Mini-shinkansen|ミニ新幹線}} is the name given to the routes where former narrow-gauge lines have been converted to standard gauge to allow Shinkansen trains to travel to cities without the expense of constructing full Shinkansen standard lines.

Two mini-shinkansen routes have been constructed: the [[Yamagata Shinkansen]] and [[Akita Shinkansen]]. Shinkansen services to these lines traverse the [[Tohoku Shinkansen]] line from Tokyo before branching off to traditional main lines. On both the Yamagata/Shinjo and Akita lines, the narrow-gauge lines were regauged, resulting in the local services being operated by [[701-5000 series|standard-gauge versions]] of {{Track gauge|1,067mm}} suburban/interurban rolling stock. On the Akita line between Omagari and Akita, one of the two narrow-gauge lines was regauged, and a section of the remaining narrow-gauge line is dual gauge, providing opportunity for Shinkansen services to pass each other without stopping.

The maximum speed on these lines is {{convert|130|km/h|mph|abbr=on}}, however the overall travel time to/from Tokyo is improved due to the elimination of the need for passengers to change trains at [[Fukushima, Fukushima|Fukushima]] and [[Morioka, Iwate|Morioka]] respectively.

As the [[Loading gauge]] (size of the train that can travel on a line) was not altered when the rail gauge was widened, only Shinkansen trains specially built for these routes can travel on the lines. They are the E3 and E6 series trains.

Whilst no further Mini-shinkansen routes have been proposed, it remains an option for providing Shinkansen services to cities on the narrow-gauge network.{{Citation needed|date=May 2025}}

====Proposed Ou Base Tunnel====
Construction of a [[Base tunnel]] on the [[Yamagata Shinkansen]] is proposed, with JR East having undertaken a survey of a planned route from Niwasaka to Sekine, just south of Yonezawa station.<ref>{{Cite web |date=7 November 2022 |title=Yamagata mini-Shinkansen base tunnel proposal makes progress |url=https://www.railwaygazette.com/infrastructure/yamagata-mini-shinkansen-base-tunnel-proposal-makes-progress/62884.article |url-access=subscription |access-date=12 November 2022 |website=Railway Gazette International }}</ref> {{convert|23.1|km|mi|abbr=on}} of the proposed {{convert|24.9|km|mi|abbr=on}} line would be in tunnel, mostly to the north of the existing {{convert|88|km|mi|abbr=on}} Fukushima – Yamagata section. To be built on an improved alignment, the tunnel would lower journey times between Fukushima and Yamagata by ~10 min due to a proposed line speed of up to 200&nbsp;km/h.

The tunnel would avoid the Itaya Toge pass through the Ou mountains west of Fukushima. Gradients range from 3.0% to 3.8% and the line reaches an altitude of {{convert|548|m|ft|abbr=on}}. The curvature and steep grades limit train speeds to {{convert|55|km/h|mph|abbr=on}} or less, and the line is vulnerable to heavy rain and snowfall as well as high winds. Between 2011 and 2017 a total of 410 Yamagata mini-Shinkansen services were either suspended or delayed, and 40% of these incidents occurred on the line over the Itaya Toge pass.

If the {{Yen|150 billion}} base tunnel is authorised, detailed design would take five years and construction another 15 years. The cost could increase by {{Yen|12 billion}} if the tunnel were to be built with a cross-section large enough to permit the line to be upgraded to the full Shinkansen loading gauge.

=== Gauge Change Train ===
{{Main|Gauge Change Train}}

This is the name for the concept of using a single train that is designed to travel on both {{RailGauge|1067mm}} narrow-gauge railway lines and the {{RailGauge|1435mm}} standard gauge used by Shinkansen train services in Japan. The trucks/bogies of the Gauge Change Train (GCT) allow the wheels to be unlocked from the axles, narrowed or widened as necessary, and then relocked. This allows a GCT to traverse both standard-gauge and narrow-gauge tracks without the expense of regauging lines.

Three test trains were constructed, with the second set having completed reliability trials on the [[Yosan Line]] east of [[Matsuyama, Ehime|Matsuyama]] (in [[Shikoku]]) in September 2013. The third set was undertaking gauge changing trials at [[Shin-Yatsushiro Station]] (on [[Kyushu]]), commencing in 2014 for a proposed three-year period, however testing was suspended in December 2014 after accumulating approximating {{convert|33,000|km|mi|abbr=on}}, following the discovery of defective thrust bearing oil seals on the bogies.<ref name="mynavi20141224">{{cite web |date=24 December 2014 |title= |script-title=ja:九州新幹線のフリーゲージトレイン、欠損が見つかり耐久走行試験を一時休止 |trans-title=Kyushu Shinkansen Free Gauge Train endurance testing suspended following discovery of defects |url=http://news.mynavi.jp/news/2014/12/24/335/ |archive-url=https://web.archive.org/web/20211227101301/https://news.mynavi.jp/article/20141224-a335/ |archive-date=27 December 2021 |access-date=11 July 2022 |work=Mynavi News |publisher=Mynavi Corporation |location=Japan |language=ja}}</ref> The train was being trialled between [[Kumamoto]], travelling on the narrow-gauge line to Shin-Yatsushiro, where a gauge changer was installed, so the GCT could be trialled on the Shinkansen line to [[Kagoshima]]. It was anticipated the train would travel approximately {{convert|600,000|km|mi|abbr=on}} over the three-year trial.

A new "full standard" Shinkansen line was opened in 2022 from Takeo Onsen to {{STN|Nagasaki|x}}, with the Shin-Tosu – Takeo Onsen section of the [[Nishi Kyushu Shinkansen]] remaining narrow gauge. GCTs were proposed to provide Shinkansen service from the line's opening, however with the GCT being cancelled, JR Kyushu announced it would provide an interim [[Kamome (train)#Nishi Kyushu Shinkansen|'relay']] service.<ref name="ReferenceB" />

There are currently no further proposals for use of the GCT, nor any development work on it.