GWR 4800/1400 Class

The GWR 4800/1400 Class was a series of seventy-five outside-cylinder 0-4-2 auto-trailer tank locomotives designed by Charles Collett and built at Swindon Works from 1932, designed specifically for the GWR's push-pull auto-trailer services on rural branches and lightly-used secondary lines. The auto-trailer system — in which the locomotive could propel a specially-fitted passenger trailer from the other end of the train without running round at termini, with the driver controlling the locomotive remotely from a cab in the trailer — was the GWR's solution for operating rural branches economically, eliminating the time and infrastructure cost of locomotive run-round manoeuvres at every terminus.

Collett designed the 1400 Class (the locomotives were renumbered from 4800 to 1400 series) as a dedicated auto-tank type, the successor to the Victorian-era 517 Class that had long served the GWR's auto-trailer branches. The 0-4-2T wheel arrangement gave a compact, lightweight locomotive with the trailing axle providing weight distribution for the firebox and the short coupled wheelbase allowing operation on the tight curves of rural branch lines. The outside cylinders gave good accessibility for maintenance at the small rural depots that served these lines.

The 1400 Class worked the GWR's rural branch auto-trailer services across the West of England and South Wales — the Exe Valley line, the Teign Valley, the Hemyock branch, the Wallingford branch, and dozens of others — until the closure of these lines under the Beeching cuts and the replacement of steam by diesel multiple units in the early 1960s. Several examples are preserved on heritage railways, where their association with the GWR's rural branch heritage makes them particularly evocative of a lost way of travelling.