Yamagata Shinkansen

Operations

Trains consist of 7-car E3 and E8 series trainsets operating as Tsubasa services. Between and , most trains run coupled to Yamabiko limited-stop service trains on the Tōhoku Shinkansen. Between Fukushima and Shinjō, the trains run on their own at a maximum speed of 130 km/h and share the line with regular Ōu Main Line trains.

As of July 2012, about 62 million passengers had ridden the line since it opened in July 1992.

The fastest trains connect Tokyo and Yamagata stations in two hours and 29 minutes.

Station list

• All stations listed below are located on the Ōu Main Line.

Rolling stock

As of March 2024, the following types are used on Yamagata Shinkansen services:

• E3-2000 series: 7 car sets, since 20 December 2008 (to be replaced by E8 series in 2026)
• E8 series: 7-car sets, since 16 March 2024 File:E3-2000-L67-of-Yamagata-Shinkansen.jpg|E3-2000 series set in original livery File:E3-2000 L67 Akayu Tsubasa 128 20150905.jpg|E3-2000 series set in new livery File:E8系(大宮駅).jpg|E8 series set

Former rolling stock

• 400 series: 7-car sets (originally 6-car sets) withdrawn by 18 April 2010
• E3-1000 series: 7-car sets, in service from 4 December 1999 until 18 March 2024. File:JR East shinkansen 400 tsubasa 6cars.jpg|400 series, 6-car set in original livery File:E3-1000 L54 Tsubasa 144 Kita-Yamagata 20150307.jpg|E3-1000 series set in new livery

Non-revenue-earning-types

• Class E926 "East i" File:Shinkansen E926 East-i.jpg|Class E926 "East i" train

History

The tracks of the Ōu Main Line were re-gauged between 1988 and 1992 to create the Yamagata Shinkansen. Tsubasa services began on 1 July 1992, operating between Tokyo and Yamagata using six-car 400 series trainsets coupled to 200 series trains on the Tōhoku Shinkansen between Tokyo and Fukushima. On 1 December 1995, the trains were lengthened to seven cars, and the line was subsequently extended northward to Shinjō on 4 December 1999. All cars were designated non-smoking from 18 March 2007.

A major rolling stock transition occurred on 20 December 2008, when E3-2000 series trainsets entered service, replacing the earlier 400 series, which were fully withdrawn on 18 April 2010. Operations were severely disrupted following the 2011 Tōhoku earthquake and tsunami on 11 March 2011, which led to the suspension of all services. Partial operations resumed between Fukushima and Shinjō on 31 March 2011, and full through-services between Tokyo and Shinjō were restored on 12 April 2011, albeit at approximately half of the previous capacity.

Services were disrupted on 13 February 2021, when operations north of Nasushiobara Station were suspended following the 2021 Fukushima earthquake.

In March 2020, JR East announced two major projects to improve the line. The first was the introduction of the E8 series trains, designed to increase maximum speeds on the Tōhoku Shinkansen to 300 km/h and reflect the landscape and cultural identity of Yamagata Prefecture. Delivery began in 2023 and is scheduled to conclude in 2026, when the E8 series will replace the remaining E3 series. The second project is the construction of a new approach line at Fukushima Station to remove a bottleneck. Previously, southbound Yamabiko services coupling with Tsubasa trains had to cross the northbound main line twice to access Platform 14. The new track will branch from the Ōu Main Line, pass beneath the elevated Shinkansen, and connect directly to Platform 11, eliminating at-grade crossings and allowing simultaneous arrivals and departures, improving timetable flexibility. Completion is scheduled for 2026.

On 9 June 2022, the line celebrated its 30th anniversary; an E3 series trainset was wrapped in a commemorative livery and remained in service until November 2022.

The E8 series entered service on 16 March 2024. On 17 June 2025, four E8 series trainsets experienced auxiliary power unit (APU) malfunctions. The APU converts electricity collected from the overhead lines into the appropriate forms required by onboard systems, including traction motors and cooling equipment. Each trainset is equipped with two APUs to provide redundancy.

The E8 series entered service on 16 March 2024. On 17 June 2025, four E8 series trainsets suffered malfunctions of their auxiliary power units (APUs), which convert electricity from overhead lines for onboard systems. In one case, a trainset stopped on the Tōhoku Shinkansen, blocking the line, stranding passengers, cancelling 86 services, and delaying 138 others across the Tōhoku, Yamagata, and Akita Shinkansen lines. JR East suspended independent E8 operation, limiting them to multiple working and temporarily reinstating some E3 trains, reducing Yamagata Shinkansen service to roughly 80% of normal. Investigations found that an electrical issue, combined with high summer temperatures, caused protective components to fail, allowing excess current to reach and damage sensitive electronic systems. After installing stronger protective components and revising settings, independent operation and through services gradually resumed from 1 August 2025.

Future

Proposed Ou base tunnel

JR East has proposed the construction of a base tunnel through the Ōu Mountains west of Fukushima, with a surveyed route between and . Of the proposed 24.9 km line, 23.1 km would be underground, located mostly north of the existing line, and follow a more direct alignment intended to reduce journey times by approximately 10 minutes through a proposed line speed of up to 200 km/h. The tunnel would bypass the Itaya Toge pass, where gradients of 3.0–3.8% and an altitude of 548 m currently limit speeds to 55 km/h or less and leave the line vulnerable to heavy rain, snow, and high winds; between 2011 and 2017, 410 Tsubasa services were delayed or suspended, 40% of which occurred on the Itaya Toge section. If authorized at an estimated cost of , detailed design would take five years and construction a further 15 years, with an option to build the tunnel to the full Shinkansen loading gauge for an additional .

References

References

1. (April 2012). "300 km/hのトップランナー". Koyusha Co., Ltd..
2. (3 July 2012). "Yamagata Shinkansen Line turns 20". The Japan Times Ltd..
3. (16 March 2024). "山形新幹線 25年ぶりの新型車両「E8系」営業運転開始".
4. (19 March 2024). "E3系L53編成が新潟へ". Koyusha Co., Ltd..
5. [[NHK]], "Yamagata Shinkansen fully resumes operations", 12 April 2011.
6. (14 February 2021). "Tohoku Shinkansen line breaks from the base of utility poles".
7. (3 March 2020). "山形新幹線をより便利に快適にします". 東日本旅客鉄道株式会社.
8. "JR East Announced New E8 Shinkansen Trains".
9. "山形新幹線E3系つばさ、つなぐ.:JR東日本".
10. (2021-05-24). "Wayback Machine".
11. Kamishin, Daisuke. (2020-03-03). "JR東日本、山形新幹線の福島駅アプローチ線新設工事".
12. (7 June 2022). "山形新幹線開業30周年を記念したラッピング車両を運転".
13. (18 June 2025). "3 more bullet trains report issues after service halt in east Japan". [[Kyodo News]].
14. (18 June 2025). "JR East: Power supply system malfunction likely caused E8 Shinkansen shutdown". [[NHK World-Japan]].
15. (25 June 2025). "JR East: Shinkansen train power supply systems had damaged chips". [[NHK World-Japan]].
16. (25 June 2025). "東北・山形新幹線E8系、補助電源装置の半導体に損傷 JR東日本「6台ともぐちゃぐちゃ、かつてない」". [[Tokyo Shimbun]] Digital.
17. (18 June 2025). "18日も東北・山形新幹線が一部運休 17日の車両故障の影響続". [[The Asahi Shimbun.
18. (18 June 2025). "JR East investigating possible flaw in E8 series Shinkansen trains". [[NHK World-Japan]].
19. (18 June 2025). "東北新幹線、新型「E8系」の単独運行を取りやめ 長時間の運転見合わせ、電源装置の故障が原因 JR東日本". [[Tokyo Shimbun]] Digital.
20. (25 June 2025). "東北･山形新幹線E8系、電源装置の半導体が損傷 原因は不明". [[The Nikkei]].
21. (25 June 2025). "山形新幹線 現在の調査経過と当面の対応について". East Japan Railway Company.
22. (23 July 2025). "山形新幹線「E8系」故障、原因を特定 想定より高い電流+気温上昇で半導体素子が損傷".
23. (7 November 2022). "Yamagata mini-Shinkansen base tunnel proposal makes progress".
24. (2023-01-23). "Yamagata pins hopes on shinkansen tunnel, but faces roadblocks".
25. (2022-11-14). "A 23 km tunnel planned on Yamagata Shinkansen – Difficult section with heavy snowing – [WTM] Railway & Travel News".