British Rail Class 166

British Rail Class 166 "Network Express Turbo"
Class 166, no. 166202, at Evesham on 19 September 2004, with a service to London Paddington via the Cotswold Line.
In service1992 - Present
Family nameNetworker
Number built21 trainsets
Formation3 cars per trainset
Fleet numbers166201 - 166221
Operator(s)First Great Western
Maximum speed90mph
Prime mover(s)Perkins 2006TWH
Safety system(s)AWS, TPWS
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The British Rail Class 166 "Network Express Turbo" diesel multiple units (also known as just "Thames Turbos" [1] ) were built by ABB at York Works from 1992-93. These units are the express version of the Class 165 "Network Turbo" units. They have a top speed of 90mph (suitable for mainline use), are carpeted throughout and have air-conditioning (the 165s lack the latter two features and it should be noted the 166 is similar to the Class 158 in terms of what it offers).


  1. "First Great Western Info".