PASSENGERS in Japan’s northern island of Hokkaido are reaping the benefits of the country’s latest build of tilting diesel multiple-units. Marketed as Super Soya, the four-car Series 261 sets have cut the journey time between Sapporo and Wakkanai by 54min to 4h 58min.
The new trains are the final development in a 3·2bn yen programme to upgrade the 285·3 km Soya line from Asahikawa to Wakkanai, which is the most northerly line in Japan. Funded jointly by JR Hokkaido and local authorities, work started in 1997.
The air-conditioned Series 261 cars are derived from the Series 201 high-performance commuter EMUs, but with a revised interior layout to suit their limited express role. Each four-car set is powered by seven underfloor N-DMF13hzh engines rated at 460hp at 2100rev/min, making them significantly more powerful than the earlier Series 283 tilting units.
The tilt system uses an electronic yaw-rate gyroscope to detect curves and inflate the bogie air springs on the outer side of the suspension, giving a maximum of 3° of active tilt. This is around one-tenth of the cost of the Series 283 tilt system, but still allows the Series 261s to run through curves of 600m radius 25 km/h faster than the normal line speed. Top speed of the 1067mm gauge unit is 130 km/h.
Interior design was developed by JR Hokkaido with the assistance of Danish State Railways, and draws heavily on the DSB IC-3 Flexliner. Each unit provides 204 seats, including nine in the Green Car. Seating fabrics in standard class alternate between blue, red and green, with dark grey seatback tables. Oak and sycamore wood is used for the partitions, and the flooring has a diagonal pattern to increase the feeling of space.
For the first time in Japan, the Green Car seats have leather upholstery with wooden armrests, matching the wood partitions. These seats have individual reading lamps and electrical outlets to power laptop computers. General lighting is provided by slit-panel fluorescents and halogen downlighters.
CAPTION: The Super Soya’s diagonal flooring and wood trim is continued through both the standard seating areas (below) and Green Car (below right)
