The British Rail Class 166 Networker Turbo is a fleet of diesel multiple unit (DMU) passenger trains, built by ABB Transportation at their Holgate Road Works in York between 1992 and 1993. They were specified by and built for British Rail, the state-owned railway operator in Great Britain at the time. The trains were designed as a faster, air-conditioned variant of the Class 165 Turbo, intended for longer-distance services, and, like the 165s, belong to the Networker family of trains. They are known as Networker Turbos to distinguish them from the electrically propelled members of that family. Today the 166s, alongside the 165s, are normally referred to as Thames Turbos, the Networker Turbo Express or just simply Turbos.
Great Western Railway Class 166 at Didcot Parkway in 2015
Refurbished standard-class saloon
166220 arrives at Oxford with a service to London Paddington.
Great Western Railway unit 166212 at Clifton Down on the Severn Beach Line in Bristol, July 2017
A diesel multiple unit or DMU is a multiple-unit train powered by on-board diesel engines. A DMU requires no separate locomotive, as the engines are incorporated into one or more of the carriages. Diesel-powered single-unit railcars are also generally classed as DMUs. Diesel-powered units may be further classified by their transmission type: diesel–mechanical DMMU, diesel–hydraulic DHMU, or diesel–electric DEMU.
A JNR Class KiHa40 in use for Erimo Express service, Hokkaido, Japan
An IE 29000 Class diesel multiple unit on a western commuter service at Dublin Connolly Rail station, Ireland
A British Rail Class 185 diesel hydraulic multiple unit operated by TransPennine Express at Manchester Piccadilly station, United Kingdom
One of the underfloor diesel engines with hydraulic transmission under a car of JR Shikoku 2700 series DMU
