400 Series Shinkansen
The 400 series (400系) was a Japanese Shinkansen high-speed train type operated by East Japan Railway Company (JR East) between 1992 and 2010 on Tsubasa services on Japan's first Mini-shinkansen line, the Yamagata Shinkansen branch from the main Tōhoku Shinkansen.
The fleet of 400 series trains was leased by JR East from the owning company, Yamagata JR Chokutsū Tokkyū Hoyū Kikō (山形ジェイアール直通特急保有機構(株)), a third-sector company jointly owned by JR East and Yamagata Prefecture.
They were originally six-car sets, but a seventh car (type 429) was added in 1995 to each set due to the popularity of the new Tsubasa services.
Pre-series set
The pre-series set, S4, was delivered in October 1990, and shown off to the press on 26 October 1990. This was a six-car set arranged as shown below with all cars motored.
The unit featured three different types of bolsterless bogies: DT9028 on cars 1 and 3, DT9029 on cars 2 and 4, and DT9030 on cars 5 and 6. The Green car seats featured seat-back TV screens, a feature not used on the subsequent production sets.