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 through-out 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).
Twenty-one 3-car units were built, numbered 166201-221. Each unit was formed of two outer driving motors, and an intermediate motor. The technical description of the formation is DMCL+MS+DMCL. Individual carriages are numbered as follows:
* 58101-58121 - DMCL
* 58601-58621 - MS
* 58122-58142 - DMCL
The units were built to replace elderly Class 117, Class 119 and Class 121 "Heritage" DMUs, and locomotive-hauled trains on services from London Paddington along the Great Western Main Line. Their main destinations included fast-trains to Reading, Newbury and Oxford, with some services continuing beyond Oxford to Banbury and Stratford-upon-Avon, or along the Cotswold Line to Evesham, Worcester, Great Malvern and Hereford. Additionally, units are also used on the Reading to Gatwick Airport services along the North Downs Line.
When built, these units were operated by the Thames Line and North Downs Line subdivisions of Network SouthEast, and therefore these units carried NSE blue, red and white livery.
Following privatisation, the units passed to the Thames Trains franchise, who introduced a new blue, white and green livery. There were two variants of this livery; the Express livery carried by Class 166 units had full-height green swish over the doors, whereas the Class 165 units had smaller green circles over the doors.
In April 2004, operation of the Thames Trains franchise passed to the First Group, who now operate the company as First Great Western. The livery remained the same, but FGW Link branding was applied over the obsolete Thames Trains logo. Since April 2006 First Great Western Link has rebranded First Great Western to coincide with The Greater Western Franchise. In October 2006 the first unit (166220) was repainted in the new First Great Western 'dynamic lines' livery.
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "British Rail Class 166".
; "166 Turbo 3 Car DMU 'First Great Western' 2006 Livery")