British Rail Class 124

The BR Class 124, known as the Trans-Pennine units, were a fleet of six-car diesel multiple unit sets built in 1960 at BR Swindon Works for the demanding Trans-Pennine express services across the Pennines between Manchester, Leeds, Hull, and Newcastle. Eight sets were constructed, designed to provide fast, comfortable express travel on a route that had previously been worked by locomotive-hauled trains and where the severe gradients, numerous tunnels, and exposed moorland crossings demanded reliable and capable motive power.

Each six-car set comprised two driving motor brake seconds, two trailer firsts, and two trailer seconds, with a total of four Leyland Albion 230 hp engines per set giving sufficient power for sustained running on the Trans-Pennine grades. The sets were built to a high interior specification — described at the time as the most comfortable DMU accommodation on BR — with airline-style seating, individual ventilation, and large windows designed to showcase the Pennine scenery. They were capable of 90 mph and regularly achieved high average speeds on the challenging cross-Pennine alignment.

The eight sets worked Trans-Pennine services throughout the 1960s and 1970s. By the early 1980s, locomotive-hauled services and newer rolling stock had displaced them from the principal Trans-Pennine workings, and they were withdrawn in 1984. No complete set was preserved, though some individual vehicles survive in heritage stock at various locations.