The KiHa 183-1000 series, currently branded Aso Boy!, is a charter-only express diesel multiple unit operated by the Kyushu Railway Company since March 1988. The sole four-car set has gone through a number of guises and rebrandings over its years of operation.
The KiHa 183-1000 series cars were manufactured in 1988 by Fuji Heavy Industries and JR Kyushu's Kagoshima Works as a new train that would allow commuters to access the Nagasaki Holland Village, a now-closed theme park in Nagasaki that served as inspiration for the Huis ten Bosch theme park which came later. The cars were designed to be diesel railcars so that they could be used around the Kyushu network without need for electrification.
The first three cars were manufactured on 22 February 1988; both cab cars were manufactured were manufactured by Fuji Heavy Industries while the intermediate car was manufactured at JR Kyushu's Kagoshima Works in knockdown kit format. The set was then put into service on 13 March 1988 in a three-car format as the Holland Village Express; when various limited express trains began plying the route, it became clear that JR Kyushu had to match the operating schedules of the Holland Village Express with those of the limited express trains as closely as possible.
In 1989, an additional car manufactured by Fuji Heavy Industries was added to the set, making it a four-car consist. In 1992, the set was withdrawn from service to become the Yufuin no Mori II set to increase the number of limited express services on the Kyūdai Main Line. It served in this role until 1999, when it was refurbished again to become the Siebold set, sporting a paintjob very similar to that of its Holland Village Express days. The set would be refurbished yet again in 2003, becoming the Yufu DX set; the set also had its prime movers swapped out for new ones during this refurbishment. The cars were originally painted a deep red but were repainted yellow in 2008. The set underwent its last refurbishment to date in 2011, becoming the Aso Boy! set for use on the Hōhi Main Line, where it remains to this day. The set is currently based at Kumamoto Depot.
While technically a Joyful Train as it contains many features most Joyful Trains have, JR Kyushu officially does not consider the train as such.
Design[]
The KiHa 183-1000 series feature a unique panoramic design with a large frontal windshield, allowing passengers to see the tracks ahead. The design of the cars is extremely similar to that of Meitetsu's Panorama Cars, featuring a raised cab above the main passenger area accessed through a hatch in the ceiling. The set's livery changes each time it is refurbished, the specifics of which are detailed in the table below.
Construction is of steel. Performance statistics are largely identical to that of the N183 series cars these were based on; this article will still detail the performance statistics of the cars after their refurbishment.
Special dual coupler
After the cars's third refurbishment into the Yufu DX set, the cars's prime movers were swapped out with DMF13HZA and Komatsu SA6D140HE-2 prime movers; KiHa 182-1002 received the former prime mover while the other three cars received the latter prime mover. Each prime mover produces 444 HP (450 PS).
The current interior of the Aso Boy! set features a children-centric design, with pictures of Kuro (lit. "black"), the train's mascot, scattered around the train. Children's play areas are also found around the train. Small white abreast seats are placed by the windows for children to sit. The overall design of the Aso Boy! refurbishment was carried out by Don Design Associates managing director Eiji Mitooka. The cars feature a special dual Shibata-knuckle coupler with the couplers attached 90 degrees from each other on a rotating post.