Tobu N100 series

The Tobu N100 series (東武N100系), branded Spacia X (スペーシアX), is an electric multiple unit (EMU) train type operated by the private railway operator Tobu Railway on limited express services in Japan since 15 July 2023. A total of four 6-car sets were built by Hitachi to replace the 100 series EMUs which have been in service since 1990.

History
Details of the N100 series were first announced on 11 November 2021. The N100 series is intended to succeed the 100 series Spacia as Tobu's flagship limited express fleet. Production of the fleet began in fiscal 2022, with the first two sets, N101 and N102, being delivered from Hitachi's Kasado plant from 5 March 2023. The last two sets were delivered from the Hitachi plant from February 2024.

The N100 series fleet entered service from 15 July 2023.

Design
The N100 series is part of Hitachi's A-train family, and uses aluminium body construction. It is a recipient of the 2023 Good Design Award and 2024 Blue Ribbon Award.

Exterior
The N100 series sets are painted in a shade of white that takes influence from the color of the Yomeimon gate at the Nikko Tosho-gu shrine. The end cars are fitted with hexagonal side windows, whose frames are inspired by the Japanese "kumiko" woodworking technique.

The train ends each feature an LED panel with 39 LEDs, functioning as a headlight and taillight cluster; when switched on, the headlights form a "T" shape. External LCD destination displays are located at the sides of each car.

Interior
The interior consists of the following accommodations:


 * Cockpit Lounge (car 1): The Cockpit Lounge consists of sofas and lounge chairs. Two lounge chairs face the driver's cab, allowing passengers a front view. A bar, which serves beer, coffee, and snacks, is located at the rear of the Cockpit Lounge. Car 1's vestibule features an artificial skylight.
 * Premium seating (car 2): Seats are arranged in a 2+1 abreast configuration with a seat pitch of 120 cm. The seats use orange fabric, which was chosen to make the seats stand out from the dark grey flooring. They also incorporate a back shell structure, which Tobu Railway states allows for reclining without impacting rearward passengers.
 * Standard class (cars 3–5): Seats are arranged in a 2+2 abreast configuration with a 110 cm seat pitch, the same as that of the outgoing 100 series. Cars 3 and 4 consist of standard class accommodation throughout (56 seats each), and car 5 has 18 standard class seats, wheelchair spaces, and two 2-person semi-compartmentalized seating bays.
 * Cockpit Suite (car 6): Situated behind the driver's cab, the Cockpit Suite is an 11 m2 space which seats up to seven passengers (four seats and a three-person sofa). The suite and the driver's cab are separated by a glass barrier, also allowing passengers a view from the front. Also featured in car 6 are four 4-person compartments, with sofas that form a "U" shape. The compartments are situated directly behind the Cockpit Suite. Like car 1, car 6's vestibule features an artificial skylight.

Operations
The N100 series fleet operates between Asakusa and Kinugawa-Onsen (or Tobu-Nikko) stations on the Tobu Skytree, Nikko, and Kinugawa lines. Originally, the type only made two round trips per day (four on Thursdays, Fridays, Saturdays, and holidays) but with the start of the 16 March 2024 timetable revision, the frequency was increased to four trips daily throughout the week.

Unlike the 100 series, the N100 series cannot run on JR East lines.

Formation
The N100 series sets consist of four intermediate motored cars with non-powered (trailer) end cars. They are formed as shown below.


 * Cars 3 and 5 are each equipped with two single-arm pantographs.
 * Cars 2 and 5 are equipped with toilets.