Draft:Fukuoka Subway 4000 series

The Fukuoka Subway 4000 series (福岡市交通局4000系) is an electric multiple unit (EMU) train type on order by the Fukuoka City Transportation Bureau for use on the Hakozaki Line and Kūkō Line in Fukuoka, Japan.

The type is due to enter service in the latter half of 2024.

Design
The 4000 series trains are the first in the world to implement synchronous reluctance motors on a full scale; they are expected to offer 20% energy savings over older, induction motor-driven trains.

Internally, the trains use longitudinal seating throughout. With a per-person seat width of 480 mm, the 4000 series features the widest seats of any commuter train in Japan.

History
In June 2021, the Fukuoka City Transportation Bureau announced that it was seeking out manufacturers to build new rolling stock to replace its fleet of 1000N series trains. It was announced on 7 February 2022 by Kawasaki Heavy Industries that its rolling stock division, Kawasaki Railcar Manufacturing, would produce the new trains at a cost of approximately.

Details of the trains were first announced by the Fukuoka City Transportation Bureau on 30 November 2023.

The first set, 25, was delivered from the Kawasaki Railcar Manufacturing plant in Hyogo from 23 April 2024.