British Rail Class 141 Pacer | |
---|---|
In service | 1984–2005 |
Manufacturer | |
Order no. |
|
Built at | Derby Litchurch Lane Works |
Family name | Pacer |
Constructed | 1984 [3] |
Refurbished | 1988–1989 |
Number built | 20 |
Number preserved | 2 |
Number scrapped | 4 |
Formation | 2 vehicles: DMS-DMSL |
Diagram |
|
Fleet numbers | |
Capacity | 94 seats [1] |
Operators | |
Depots | Neville Hill (Leeds) [2] |
Specifications | |
Car body construction | Steel [1] |
Car length | 15.123 m (49 ft 7.4 in) [1] |
Width |
|
Height | 3.906 m (12 ft 9.8 in) [1] |
Doors | Double-leaf folding (one per side per car) |
Wheelbase | 9.000 m (29 ft 6.3 in) [1] |
Maximum speed | 75 mph (121 km/h) |
Weight |
|
Prime mover(s) | 2 × Leyland TL11 (one per vehicle) [1] |
Engine type | Inline-6 4-stroke turbo-diesel [6] |
Displacement | 11.1 L (680 cu in) per engine [6] |
Power output | 149 kW (200 hp) per engine [7] |
Transmission | SCG RRE5 (4-sp. epicyclic) [7] |
Minimum turning radius | 70 m (230 ft) [1] |
Braking system(s) | Electro-pneumatic (tread) ('Westcode') |
Safety system(s) | AWS |
Coupling system | |
Multiple working | As built: Not fitted [1] |
Track gauge | 1,435 mm (4 ft 8+1⁄2 in) standard gauge |
The British RailClass 141 is the first production model of the Pacer diesel multiple unit (DMU) railbus.
During the 1980s, British Rail (BR) was interested in replacing its first generation diesel multiple units, particularly in the use of railbuses to service its lightly used branch lines. It was decided to develop such a vehicle with a high level of commonality with the widely used Leyland National bus, leading to its modular design serving as the basis for the design. Several single and two-car prototypes were constructed and evaluated, before an order was placed with British Leyland for 20 two-car Class 141 units during 1984. During their operating lives, the units were tasked with various passenger services across the UK for 13 years. Following withdrawal, a large proportion of the units were exported to Iran where they operated for a further eight years, giving the Class 141 a total lifespan of 21 years.
By the beginning of the 1980s, British Rail (BR) operated a large fleet of first generation DMUs, which had been constructed in prior decades to various designs. [9] While formulating its long term strategy for this sector of its operations, British Rail planners recognised that there would be considerable costs incurred by undertaking refurbishment programmes necessary for the continued use of these ageing multiple units, particularly due to the necessity of handling and removing hazardous materials such as asbestos. In light of the high costs involved in retention, planners examined the prospects for the development and introduction of a new generation of DMUs to succeed the first generation. [7]
In the concept stage, two separate approaches were devised, one involving a so-called railbus that prioritised the minimisation of both initial (procurement) and ongoing (maintenance & operational) costs, while the second was a more substantial DMU that could deliver superior performance than the existing fleet, particularly when it came to long distance services. [7] While the more ambitious latter requirement would ultimately lead to the development of the Class 150 and the wider Sprinter family of DMUs, BR officials recognised that a cheaper unit was desirable for service on the smaller branch lines that would not be unduly impacted by lower performance specs or a high density configuration. As such, work to progress both approaches was undertaken by BR's research department during the early 1980s. [7]
During this period, a number of prototypes were constructed to explore different designs and approaches for implementing the railbus concept. One such vehicle was a single two-car unit, designated as the Class 140, that was constructed between 1979 and 1981. [10] This prototype was introduced with much fanfare during June 1981. [10] Initial testing with the Class 140 uncovered several issues, such as difficulty detecting the type via track circuits, this was reliably resolved by swapping the material of the brake blocks from a composite to iron. [7] Two less easily-addressable drawbacks were the high level of noise generated during transit, particularly on older jointed rails, which was a consequence of the railbus's direct connection between the underframe and suspension with the body that transmitted impact forces across the body. It was also observed that the inclusion of strengthening members in the mass-produced bus body added significantly to the overall production cost, which eliminated much of the cost advantage that was the primarily goal of the type. [7]
The Class 140 was viewed to be an overall success, and thus BR issued an order for an initial production model, designated Class 141, to British Leyland during 1984 with production commencing thereafter. [7] In subsequent years, follow-on orders would be placed, but these would be for improved derivatives of the Class 141, these being the Class 142 and Class 143 respectively. Unlike these later siblings, the Class 141 had a noticeably narrower body, having equal width to that of the standard bus; subsequent production models expanded this to maximise internal volume. [7]
The Class 141 shared a very high degree of similarity to the design of the Class 140, a factor that enabled the latter to act as a driving instruction unit and demonstrator for the former. However, these production types also differed in numerous places. One major area of change is the separation between the underframe and the body above by a flexible mounting in contrast to the prototype's integration of these two sections; there was also a reduction in the depth of the underframe for maintenance accessibility. [7] Furthermore, in order to maximum cost savings, the manufacturers made use of road bus-standard electrical equipment, passenger fittings, and general cab layout wherever possible. [7]
Both the bodies and underframes were designed for interchangeability, as had been specified by BR, having been assembled upon jigs. [7] These were designed so that the entire body could be replaced during a mid-life refurbishment/reconstruction, and that the replacement body would not be limited to the exact same dimensions either. The underframe area, in addition to its structural role, accommodated all of the propulsion apparatus along with the majority of electrical gear. [7]
As originally built, the traction arrangement of the Class 141 consisted of a Leyland TL11 200 hp (150 kW) engine, and a Self-Changing Gears mechanical automatic gearbox and final drive unit on each car driving only a single axle. [7] This propulsion arrangement was in part taken from the Leyland National bus, as well as shared with the earlier Class 140 prototype. The controller for the automatic transmission was observed by BR engineers to be the cause of numerous operating failures and other reliability issues; this was allegedly due to defective relay logic and poor earthing; the issue was eventually resolved on the fleet by replacing the relay-based controller with an alternative that was microprocessor-based. [7]
Both axles (one driving per coach at the inner end) were fitted directly to the chassis rather than being mounted on bogies, unlike traditional DMUs. This uncommon arrangement has been attributed with resulting in the Class 141 units possessing a relatively rough ride, especially when traversing jointed track or points. Their combatively poor ride quality has been said to be a major factor in the general unpopularity amongst passengers.[ citation needed ]
The majority of the Class 141s were based in and across West Yorkshire on routes radiating from Leeds, where they worked up until 1997, at which point they were replaced by the improved Class 142. They were sponsored by West Yorkshire Passenger Transport Executive, and were painted in the PTE's Verona green and buttermilk livery with MetroTrain branding. 141001 was initially painted dark blue. [11] The class later receiving the red and cream Metro-Train livery.
The units became notorious for unreliability in their early years, a factor which BR was aware of and made efforts to investigate the root causes. [7] Beyond the pursuit of greater reliability, experiments were conducted into areas of enhancement such as ride comfort; one unit was refitted with a wider spring base and double dampers; both of these features were later deemed necessary to provide sufficient levels of performance and were applied to all Class 141s. [7] Accordingly, considerable improvements across the whole fleet followed a modification programme performed by Hunslet-Barclay between 1988 and 1989. At the same time, the original buckeye couplings were replaced with the BSI type that was fitted to the later Class 142 to enable more flexible working.[ citation needed ]
The units were numbered from 141001 to 141020. After modification they became 141101 to 141120, although not in order, since the opportunity was taken to match the final digits of the unit numbers with those of the vehicle numbers.
During the 1990s, unit number 141118 was modified for use as a weedkilling unit by Serco. It gained a grey and red livery and black wrap-around window surrounds. It was among the units that were later exported to Iran. A photograph of this unit, in Serco livery, at Huddersfield is shown on page 36 of Modern Locomotives Illustrated - August/September 2012.[ citation needed ]
During 1984, a single Class 141 unit was constructed for trial running in Malaysia and Thailand. Amongst other changes, the unit was re-gauged to metre gauge, and was different from the 20 British trains having only longitudinal seating for 120 passengers and space for another 140 standing. Furthermore, only one car was powered, with the other being a trailer vehicle. While the trial was conducted, it did not lead to export orders for the type. [12] After the unsuccessful trial in Thailand, the Pacer demonstrator was transported onto Malaysia and then to Indonesia for further evaluation runs. It was seen outside the Ulu Yam station in Malaysia, on a railway siding, in relatively derelict condition in 2000.[ citation needed ]
Following the end of their career with British Rail, 12 Class 141s were sold to Islamic Republic of Iran Railways and were exported during 2001/2002. [13] [14] with two spotted in service in 2005, [15] All units have since been withdrawn and replaced by new DMUs. Two units (106 & 112) were exported to the Netherlands, but these were both scrapped during 2005.[ citation needed ] Only a handful of units have remained in the United Kingdom, of which two units are in preservation: 141108 at the Colne Valley Railway, and 141113 (the only 141 to have been re-engineered with Cummins LTA10R engines and Voith hydraulic transmissions like the 142s/143s/144s) at the Midland Railway – Butterley. Two units (141103 and 141110) were formerly preserved at the Weardale Railway, of which 141103 and the one remaining car from 141110 were scrapped in March 2018. [16]
A railcar is a self-propelled railway vehicle designed to transport passengers. The term "railcar" is usually used in reference to a train consisting of a single coach, with a driver's cab at one or both ends. Some railway companies, such as the Great Western, termed such vehicles "railmotors".
Pacer was the operational name of the British Rail Classes 140, 141, 142, 143 and 144 diesel multiple unit railbuses built between 1980 and 1987. They were inexpensively developed using a passenger body based on the Leyland National bus on top of a chassis based on the HSFV1 research vehicle. The railbuses were intended as a short-term solution to a shortage of rolling stock, with a lifespan of no more than twenty years. As modernised replacements were lacking, the Pacer fleet remained in service on some lines until 2021, 37 years after their 1984 introduction.
A railbus is a lightweight passenger railcar with an automotive engine. It shares many aspects of its construction with a bus, typically having a bus body and four wheels on a fixed base instead of on bogies. Originally designed and developed during the 1930s, railbuses have evolved into larger dimensions with characteristics similar in appearance to a light railcar, with the terms railcar and railbus often used interchangeably. Railbuses designed for use specifically on little-used railway lines were commonly employed in countries such as Germany, Italy, France, the United Kingdom, and Sweden.
Regional Railways was one of the three passenger sectors of British Rail created in 1982 that existed until 1997, two years after Privatisation of British Rail. The sector was originally called Provincial.
The British Rail Class 114 diesel multiple units were built by BR Derby from September 1956 to July 1957. Forty-nine 2-car units were built, numbered E50001-49 for driving motors and E56001-49 for driving trailers. The units were used in the early days out of 40A Lincoln TMD (LN) on services all over the county, although a small number were transferred to 41A Sheffield (Darnall) during 1959/60.
British Rail produced a variety of railbuses, both as a means of acquiring new rolling stock cheaply, and to provide economical services on lightly used lines.
The British Rail Classes 101 and 102 diesel-mechanical multiple units were built by Metro-Cammell at Washwood Heath in Birmingham, England, from 1956 to 1959, following construction of a series of prototype units. These classes proved to be some of the most successful and longest-lived of BR's First Generation DMUs, second in longevity only to the Class 121, with the final five units being withdrawn on 24 December 2003. The oldest set was, by then, just over 47 years old.
The British Rail Class 150 Sprinter is a class of diesel-hydraulic multiple unit passenger trains, developed and built by British Rail Engineering Limited at York Carriage Works between 1984 and 1987 for use on regional services across Great Britain. The type is a second-generation design, built to more modern standards and based on BR's Mark 3 body design for longer-distance services. It was developed alongside the lower-cost Pacers, which were built using bus parts, for use on short-distance services. Two prototype units were built, followed by 135 production units in two batches. Subsequently, further members of the Sprinter family were developed and introduced to service, including the Class 155, Class 156, Class 158 and Class 159.
The British Rail Class 144Pacer is a diesel multiple unit (DMU) passenger train built at Derby between 1986 and 1987. British Rail, seeking to procure improved derivatives of the earlier Class 141, placed an order with the manufacturers British Rail Engineering Limited (BREL) and Walter Alexander to construct their own variant, the Class 144. A total of 23 units were constructed. All units have now retired from mainline service, though the majority of the units have been acquired for preservation on heritage railways and in other uses. As of December 2022, 19 out of the 23 units have been purchased following withdrawal for this purpose, of which 14 units are in operational condition.
The British Rail Class 142 Pacer are diesel multiple unit passenger trains built for British Rail (BR) from 1985 to 1987. They were built with a high level of commonality with the widely used Leyland National bus. They are part of the Pacer family of railbuses. The last set was withdrawn from service in 2020.
The British Rail Class 118 diesel multiple units were built by the Birmingham Railway Carriage and Wagon Company (BRCW) and introduced from 1960. It was a licence-built version of the British Rail Class 116.
The British Rail Research Division was a division of the state-owned railway company British Rail (BR). It was charged with conducting research into improving various aspects of Britain's railways, particularly in the areas of reliability and efficiency, including achieving cost reductions and increasing service levels.
The British Rail Class 143 is a diesel multiple unit railbus, part of the Pacer family of passenger trains introduced between 1985 and 1986.
The British Rail Classes 105 and 106 diesel multiple units were built by Cravens Ltd. of Sheffield from 1956 to 1959. The class were built with a side profile identical to British Railways Mark 1 carriage stock, using the same doors and windows. None were selected for refurbishment. The last passenger car was withdrawn from service in 1988.
The British Rail Class 151 was a prototype class of diesel multiple unit (DMU) developed and constructed by the British railway equipment manufacturer Metro Cammell. It was designed primarily to serve as a successor to the earlier first-generation "Heritage" DMUs operated by the British Rail (BR).
The British Rail Class 210 was a type of diesel-electric multiple unit (DEMU) passenger train designed and constructed by British Rail Engineering Limited's Derby Litchurch Lane Works.
The British Rail Class 140 was the prototype of the Pacer diesel multiple unit.
The British Rail Class 124 diesel multiple units were built by BR Swindon Works in 1960.
The British Rail Class 123 was a design of diesel multiple unit built for British Rail in 1963. They were the last first-generation DMUs built for British Railways and were built at Swindon Works. Ten of the four-car sets were built and introduced in 1963. The units bear a visible similarity to the British Rail Class 309; however, there is no 'relation' here as the two types were built by different manufacturers for different markets.
The Sprinter is a family of diesel multiple unit trains in use on the British railway system. They were built in the 1980s and early-1990s by British Rail Engineering Limited (BREL), Metro-Cammell and Leyland. Sprinters operate in almost every part of Great Britain, from rural branch lines to commuter expresses into major cities.
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