British Rail Class 318

British Rail Class 318
Class 318 in ScotRail livery at Hyndland (2016)
In service	1986 - Current
Manufacturer	BREL York
Family name	BR Second Generation (Mark 3)
Replaced	First Generation DMUs
Constructed	1985 - 1986
Refurbishment	2005 - 2007 Hunslet-Barclay, Kilmarnock 2013 - 2017 Wabtec, Doncaster
Number built	21 trainsets
Formation	3 cars per trainset
Fleet numbers	318250 - 318270
Operator(s)	Abellio ScotRail
Specifications
Maximum speed	90 mph (145 km/h)
Electric system(s)	25 kV 50 Hz AC Overhead
Current collection method	Stone Faiveley AMBR Pantograph
Braking system(s)	Disc
Track gauge	1,435 mm (4 ft 8 1⁄2 in) standard gauge

The British Rail Class 318 is an electric multiple unit (EMU) train, which operates exclusively in the Strathclyde Partnership for Transport network in West Central Scotland. The units were introduced fully on 29 September 1986 as part of the electrification of the Ayrshire Coast Line between Glasgow Central and Ayr/Ardrossan with alternating current (AC) overhead lines. Usage was extended to Largs in January 1987. They were also used on the Inverclyde Line in small numbers. The trains currently operate Argyle and North Clyde Line services.

Effectively a 3-car version of the Class 317 units but used in the Glasgow area, 21 of these British Rail Mark 3-based units were built by BREL York works between 1985-1986, to replace the elderly Class 101, Class 107, Class 120 and Class 126 diesel multiple units (DMUs) which had worked the Glasgow South Western sector for nearly 30 years. The technical description of the units are DTSO+MSO+DTSO, consisting of a central motor car (with a roof mounted Stone Faiveley AMBR pantograph and four Brush TM2141 traction motors located under the floor within both bogies (two motors per a bogie)) with a driving trailer at either end. The units run on the standard 25 kV AC overhead line system, and are standard class throughout, with one toilet located in coach C.