|This article needs additional citations for verification. (April 2012)|
|Number built||165 trainsets|
|Number in service||140 trainsets|
|Number scrapped||7 trainsets|
First Great Western
Arriva Trains Wales
Islamic Republic of Iran Railways (1997-2005)
|Track gauge||4 ft 8 1⁄2 in (1,435 mm)|
Pacer is the operational name of the British Rail Classes 140, 141, 142, 143 and 144 diesel multiple unit railbuses, built between 1980 and 1987. Intended as a short-term solution to a shortage of rolling stock (with a lifespan of no more than 20 years), as of 2015 many Pacer railbuses are still in use.
The Rail Vehicle Accessibility Regulations require that all public passenger trains must be accessible to disabled people by 2020. No Pacers currently meet this requirement and will therefore need to be withdrawn by that date unless they receive an extensive refurbishment. Porterbrook, which owns the Class 143 and Class 144 fleets, has proposed such a refurbishment, while Angel Trains which owns the Class 142 fleet does not see such a refurbishment as a viable option. The Long Term Passenger Rolling Stock Strategy for the Rail Industry indicates no new DMUs will be ordered in the next 10 years, which means Pacers will need to be replaced by existing DMUs cascaded from newly electrified lines.
The 'Pacer' series was a project by British Rail (BR) to create a train, with low running costs, for use on rural and suburban rail services. At the time, BR was under increasing financial pressure from the government including proposals to cut more rail lines. BR set a challenge to several companies to design a cheap, lightweight train similar to railbuses. Since then, 165 Pacer trains (totalling 340 carriages) have been built, with some over 30 years old by 2015.
The Pacer series was the result of an experiment to see whether the possibility of using bus parts to create a diesel multiple unit was viable. The initial prototype, known as LEV-1, was a joint project by the British Rail Research Division and Leyland Motors using a bus body mounted on a modification of an existing freight vehicle underframe (HSFV1). This was followed by the two-car prototype class 140, which was built in 1980 at the British Rail Engineering Derby works.
The prototype was joined by another 20 two-car units which formed the Class 141 fleet. The units were used mainly in Yorkshire, operating on mainly suburban services. They had a capacity of 94 passengers per two-car set, and two Leyland TL11 engines gave a total of 410 bhp (310 kW), resulting in a top speed of 75 miles per hour (121 km/h). The entire class underwent a technical upgrade in 1988 at the Hunslet-Barclay works in Kilmarnock. The units were withdrawn from use in 1997. Many were sold to the Islamic Republic of Iran Railways but have been withdrawn and are left rotting away in disused sidings in Iran, whilst a few remain in preservation. Because it used a standard Leyland National body, the Class 141 was narrower than the later Pacers, and could therefore accommodate only standard bus seating. The later Pacers had widened body panels to allow an increase in seating.
The next and largest Pacer class was the Class 142. This again was built by Leyland and BREL, in 1985. The body was based on a Leyland National bus, built at Lillyhall, Workington in Cumbria. Many fixtures and fittings of the Leyland National could be found on the units. The new class had a greater capacity of 120 passengers per two-car set and the same engines were used. The first sets were used initially on Devon and Cornwall branch lines and on commuter services in the North West. The units from Cornwall were eventually moved to Liverpool and the North-East, and the Class 142s have become a common sight on services across the North of England. The class was upgraded in the early 1990s to include more powerful Cummins engines, which gave a total power output of 460 bhp (340 kW) per two-car set. A number of units were then modified for use on the Merseyside PTE City Line on Merseyrail in the Liverpool region, which included dot-matrix route indicators, improved seating and Merseyrail PTE paintwork. This class moved into the control of First North Western at privatisation and subsequently passed on to Northern Rail and Arriva Trains Wales who have since operated it. Eight units were temporarily withdrawn from service, replaced by a cascading of British Rail Class 158s. First Great Western received 12 units on loan from Northern Rail from December 2007 to November 2011 (5 units were returned to Northern in December 2008) to cover for refurbishment of their fleet and to allow most of their Class 158 fleet to be rebuilt as 3 car sets.
Class 143 & Class 144
Around the same time of the Class 142 development, a Pacer railbus was being developed by Kilmarnock-based Hunslet-Barclay. The units used a Walter Alexander bus body. The units were given the number Class 143 and entered service in 1985. Again with two 205 bhp engines giving a total output of 410 bhp (310 kW) and a top speed of 75 mph (121 km/h), the class originally had a capacity of 122 passengers. The class was used in the North East of England, before being transferred to Wales and the South West and were moved over to Wales & West control during privatisation. They then passed on to Arriva Trains Wales and Wessex Trains, which later became part of the First Great Western franchise. The interiors were completely changed in 2000, when the Valley Lines service was introduced, with full back, coach-type seating installed throughout, along with improved fittings. This reduced seating capacity to 106 seats per set.
Then came a similar Class 144 unit, a Walter Alexander body on BREL underframe, which was introduced in 1987. A unit was formed of either a two-car set with 122 seats or a three-car set with a total capacity of 195 passengers and 690 bhp (510 kW), though still limited to 75 mph (121 km/h). The units were used in the North East, passing to Northern Spirit at privatisation, then Arriva Trains Northern and now Northern Rail.
Although the Pacer is economical, there are limitations to using bus parts for railway use. Instead of the more usual bogies, Pacers use a basic four-wheel two-axle configuration. The lack of articulation can result in a rough ride, especially over points and around tight curves. Other performance problems include poor acceleration and poor reliability for some units. On a section of line between Northwich and Greenbank in Cheshire the speed limit is 20 mph (32 km/h) but could be raised to 50 mph (80 km/h) if Pacers were banned from the line. The basic bus bench seating can also be uncomfortable, whilst the suspension has given rise to the nickname "nodding donkeys" due to the up and down motion on uneven track. The inward-opening doors similar to those found on buses can be unreliable, and the two-step entrance can make loading slower and harder for elderly people and wheelchair users.
Doubts were raised about safety after the Winsford crash, which involved an empty First North Western Class 142 colliding with a Virgin Trains Class 87 and coaching stock at Winsford, Cheshire on the West Coast Main Line. The body of the Pacer was severed from its frames, causing severe internal damage, which caused the unit to be written off.
As of 2015, the oldest Pacers are 31 years old. Because of the massive electrification programme that was approved from May 2011 to 2014, Class 142s will all be withdrawn and scrapped by 2020 whereas some of the remaining trains will receive lifespan extensions and wheelchair accessibility upgrades, that means these trains will continue to run until 2032.
A proposed replacement train is being designed by the Stratford upon Avon-based rolling stock manufacturer Vivarail, which plans to market a new class of DMU called the D-Train. These units will be built out of upcycled London Underground D78 Stock, which had previously been in service on the District line. Conversion of the old Underground stock to heavy rail use will involve re-using the aluminium bodyshells, traction motors and bogies from the D78 units and fitting them out with new diesel engines and interiors. The D-Train units are undergoing acceptance testing in 2015 and Vivarail plans to pitch them to train operating companies (TOCs), especially those bidding for the Northern Rail franchise coming up for tender on 4 February 2016.
Although most Pacer railbuses of Classes 142, 143 and 144 are still in use on the UK rail network, at least three units of the Class 141 fleet have so far been preserved for tourism use on heritage railways.
In 2011, a Pacer Preservation Society was set up with the aim of preserving at representative of the British Rail Class 142, 143 and 144 railbuses each. After the withdrawal of Pacers in 2020s many of them will see a new lease of life (not only within preservation) but also on heritage lines.
|Wikimedia Commons has media related to British Rail Pacers.|
- Alan Whitehouse (21 October 2011). "Long-term safety fears over Yorkshire's Pacer trains". BBC News.
- "Rolling Stock of Iranian Railways".
- "Angel Trains leases 30 Class 158 diesel multiple units to Northern Rail" (PDF). Northern Rail. 13 March 2007.
- "Safety fears over commuter trains". BBC News. 2 July 1999.
- "Train driver averts disaster". BBC News. 23 June 1999.
- Browne, Stefanie (15 January 2015). "Vivarail ready to start converting first LU D-Stock". railmagazine.com. Bauer Consumer Media. Retrieved 24 January 2015.