British Rail Class 92

The BR Class 92 was a fleet of forty-six Co-Co electric locomotives built between 1993 and 1996 by Brush Traction at Loughborough, designed specifically for freight and overnight passenger services through the Channel Tunnel between Britain and continental Europe. The Class 92 was a technically demanding design: it had to operate under three different electrical supply systems — 25 kV AC overhead in Britain (via the HS1 approach routes), 25 kV AC overhead in the Channel Tunnel itself (at a different frequency), and 25 kV AC overhead in France on the SNCF network — while also meeting the stringent fire safety requirements of the tunnel operators, which specified that a locomotive failure inside the tunnel must not prevent the train being moved to an emergency exit under its own power.

The three-voltage capability was achieved through sophisticated onboard power conversion equipment, with the locomotive automatically detecting the supply system and reconfiguring its electrical equipment accordingly. The Co-Co wheel arrangement with six traction motors gave outstanding tractive effort — 400 kN, the highest of any locomotive type operating in Britain — for hauling the heavy intermodal freight trains that were anticipated to fill the Channel Tunnel once freight services began. Each locomotive was rated at 6,700 hp, also the highest of any type then operating in Britain.

The forty-six locomotives were divided between British Rail/EWS (33 examples) and SNCF (13 examples), with the SNCF fleet numbered in a 92501–series. All were given names, primarily drawn from European composers, writers, and cultural figures: Beethoven, Brahms, Schubert, Victor Hugo, Moliere, and others, an appropriately international naming scheme for locomotives designed to cross national borders.

In practice the Channel Tunnel freight traffic never reached the volumes that had been projected during the Class 92's design phase, and the locomotives were significantly underemployed for much of their careers. The majority of the British fleet was placed in storage from around 2007 as EWS and then DB Schenker concentrated Channel Tunnel freight on a smaller active fleet. The overnight passenger Eurostar services for which some Class 92s had also been intended never materialised as planned. Caledonian Sleeper identified the Class 92 as suitable for hauling its overnight trains from London Euston to Scotland from 2015, using the locomotives' high power output for the demanding overnight schedules. This second career on the sleepers has given the Class 92 a prominent and valued role that was not part of its original specification.