British Rail Class 141

British Rail Class 141
*Pacer*
British Rail Class 141; Pacer
	141108 at the Colne Valley Railway
	Interior of a Class 141.
In service	1984 - 2005
Manufacturer	British Leyland
Order no.	30977 (DMS); 30978 (DMSL);
Family name	Pacer
Refurbishment	1988 - 1989
Formation	2 car; DMS+DMSL;
Diagram	DP228 (DMS); DP229 (DMSL);
Fleet numbers	141001-141020 (sets, as built); 141101-141120 (sets, from 1988-9); 55502-55521 (DMS); 55522-55541 (DMSL);
Capacity	94 (total); 50 (DMS); 44 (DMSL);
Operator(s)	British Rail 1984-1997; Islamic Republic of Iran Railways 2001-2005;
Depot(s)	Neville Hill
Line(s) served	West Yorkshire
Specifications
Car body construction	Steel
Car length	15.45 m (50.7 ft)
Width	2.5 m (8 ft 2 in)
Height	3.906 m (12.81 ft)
Articulated sections	2
Wheelbase	9 m (30 ft)
Maximum speed	75 mph (121 km/h)
Weight	26 t (26 long tons; 29 short tons) (DMS); 26.5 t (26.1 long tons; 29.2 short tons) (DMSL);
Prime mover(s)	1 × Leyland TL11
Power output	205 hp (153 kW)
Transmission	SCGR500 4-speed
Train heating	Engine waste heat; Ducted warm air;
Bogies	AX1
Braking system(s)	Air
Safety system(s)	AWS
Coupling system	BSI (outer); Bar (inner);
Headlight type	Fluorescent
Track gauge	1,435 mm (4 ft 8 1⁄2 in) standard gauge

The British Rail Class 141 was the first production model of the Pacer diesel multiple units. They were created because then British Rail had a large shortage of trains so rather than spending lots of money on expensive proper trains, they invented the Pacer. British Leyland at the time had a surplus in the production of bus bodies so the idea was to weld the bus body from an old bus on to a freight waggon chassis. The result of this was that pacers have notoriously poor suspension and are noisier around corners due to flanging (the squeaky noise that you'll sometimes hear when travelling by train). This makes them non-ideal passenger trains so they are now being replaced (or have been replaced in the case of the class 141) by new trains.