Some of the longest and heaviest trains operating on the UK^▸ (United Kingdom) network are stone trains.  With ever longer trains, two locomotives are now required and sidetracks long enough to hold the stone trains are now few and far between. In order to reduce the need for a long locomotive, Mendip Rail and investing in a new fleet of powered stone wagons. Not only will this allow the effective freight capacity of the train to increase, but it will also increase the number of powered wheels in contact with the track, reducing potential wheelspin.  Better acceleration of heavy trains will give an improved performance envelope, allowing for more train paths on mixed operation lines, and better recovery from unscheduled stops.

"We expect to see a 4% increase in maximum train capacity and a 3% end to end journey time improvement" says Alan Painter, operating director of Mendip Rail "and we can move to a common fleet across both the Foster Yeoman and Hanson ARC business units". "The rail freight industry has learned from the passenger train industry, where the majority of train are now comprised self-powered vehicles"

Initially, 110 wagons replacing the older and smaller JYA box wagons have been ordered from Astra Rail for delivery starting September 2028.  Header light locomotion short wheelbase units will be rebuilt from class 080SA units, re-geared to a top speed of 75 m.p.h. and should enter service in early 2029.