Class 150

The Class 150 Sprinter is a type of diesel multiple unit 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.

Northern Trains Class 150 at Manchester Piccadilly in 2024

Background

By the early 1980s, British Rail (BR) was managing an extensive fleet of first-generation DMUs of various designs. In formulating a long-term strategy for these operations, BR planners identified significant costs associated with refurbishing these aging units, particularly due to the necessity of handling and removing hazardous materials like asbestos. Given the high costs of retaining the existing fleet, planners explored the development and introduction of a new generation of DMUs to replace the first-generation models.

Development Concepts

During the concept phase, BR devised two approaches: one involved a railbus aimed at minimizing both procurement and operational costs, while the other was a more substantial DMU designed to outperform the existing fleet, especially on long-distance services. The initial specification for the latter was ambitious for the time, requiring a maximum speed of 90 mph (140 km/h), acceleration rates comparable to contemporary electric multiple units, compatibility with existing EMUs, passenger through-access, pressure ventilation, the ability to assist failed units, and configurations of either three or four cars.

This ambitious specification led to the development of the experimental British Rail Class 210 diesel-electric multiple unit. However, achieving the desired performance necessitated expensive equipment, particularly to meet speed, acceleration, and through-passenger access requirements. The Class 210 also faced maintainability issues due to space constraints. Despite these challenges, it was recognized that a production fleet assembled from proven components could offer greater reliability and lower maintenance costs, with an anticipated availability rate of 85 percent. The Class 210 demonstrated that significant reductions in maintenance costs were possible once initial issues were resolved, highlighting the value of a new generation of DMUs in reducing ongoing costs for BR.

Revised Specifications and Prototyping

By 1983, experiences with the Class 210 led planners to favor procuring a new generation of DMUs with revised, less demanding specifications. The top speed was reduced from 90 to 75 mph (145 to 121 km/h), as tests indicated no significant improvement in journey times due to the short distances between stations intended for the new DMUs. A propulsion system providing 7 hp (5.2 kW) per tonne was deemed sufficient for acceleration. Compatibility with other rolling stock was no longer required, although auto-coupling and auto-connecting functionality were added. The specification also called for good ride quality, a maximum noise level of 90 dB at full speed, a range of 1,000 miles (1,600 km), and an overhaul interval of five years or 350,000 miles (560,000 km).

Unlike the previous generation of DMUs, which typically used two engines per power car, the new DMUs would use a single engine per car. Adequate cooling systems were designed so that even with one failed engine, a two-car unit could continue to operate without significant performance loss. Operationally, the new DMUs were to be modular, with configurations of two to four cars that could include various passenger amenities such as toilets and luggage spaces.

Manufacturer Bids and Prototype Development

The formalized business specification was translated into a broad technical specification, avoiding unnecessary specifics while ensuring compatibility. This specification was issued to various rolling-stock manufacturers for competitive tender, with a requirement for three-car prototypes to be delivered within 18 months of order. This tight schedule was criticized for limiting manufacturers to existing industrial practices in their submissions.

Several bids were received by BR. BREL proposed a design based heavily on its successful Class 455 EMU, sharing its body and most of its running gear but with different powertrains. Metro-Cammell submitted a design using riveted aluminum construction, which offered a meaningful weight reduction compared to conventional methods. BR officials decided to proceed with prototypes from both BREL and Metro-Cammell, issuing orders for the development of these prototypes.

Design

The Class 150 is a commuter DMU available in two- or three-car configurations. Its steel bodyshell is shared with the Class 455 suburban electric multiple unit, featuring doors positioned at one-third and two-thirds along the body. Except for the prototype units 150001 and 150002 in their original configurations, each vehicle is powered by an underframe-mounted 14.01-litre (855-cubic-inch) Cummins six-cylinder turbo-diesel engine, producing 213 kW (286 hp). This engine drives a Voith T 211 r hydrokinetic transmission, which transmits power to both axles on the inner bogie via a Cardan shaft and a Gmeinder GM 180 final drive unit. The Class 150 has a design speed of 75 mph (121 km/h).

The majority of Class 150 units consist of a Driving Motor Second (DMS) vehicle, numbered in the 57xxx series, and a Driving Motor Second Lavatory (DMSL) vehicle, numbered in the 52xxx series. Both vehicles are single-class, with the DMSL containing a toilet. The two prototype units were originally built as three-car sets, including an additional Motor Second (MS) vehicle. Like other non-intercity stock of the time, the Class 150 lacks air conditioning, and ventilation is provided through opening hopper windows. Originally, passenger seating was arranged in a 3+2 configuration.

The second batch of production vehicles introduced several updates, including a new cab design with a gangway connection and a revised interior layout.

Prototypes

In 1984, BREL constructed two prototype three-car Class 150/0 units, numbered 150001 and 150002. The first unit was delivered to British Rail just 15 months after the order was placed. Unit 150001 was equipped with Cummins engines and Voith hydraulic transmission, while 150002 featured Perkins (Rolls-Royce) engines and a fully automatic gearbox developed by the Self-Changing Gears company. Aside from the powertrain differences, the two units were identical.

The prototypes' design specifications closely mirrored those of the subsequent production units, though they remained the only Class 150s built as three-car sets. Additional three-car units were later formed by adding a 150/2 car to a 150/1 set, but only the prototypes had purpose-built center cars without driving cabs. Both cab doors on the prototypes were air-operated, a feature not seen on the Class 150/1 production model but included in the later 150/2 variant.

During a demonstration run in the summer of 1985, unit 150001 stands in Platform 7 at St. Pancras

Production

The second batch of fifty units, classified as Class 150/1 and numbered 150101-150150, did not feature front-end gangway connections, which allowed passengers to move between units operating in multiple. Initially based at Derby Etches Park depot, these units were introduced in 1985, primarily operating around Birmingham and Manchester. Over the years, they were mainly restricted to commuter services.

Class 150/1

The final batch, consisting of 85 two-car units, was equipped with front-end gangway connections and classified as Class 150/2, numbered 150201-150285. These units were designed for longer-distance services. The inclusion of end gangways gave them a similar appearance to the Class 317/2 and Class 455/7 and 455/9 EMUs, also based on the Mark 3 bodyshell.

Class 150/2 in BR Sprinter livery

Some Class 150/2 units were later disbanded, and the vehicles were used to create three-car sets from some of the Birmingham and Manchester-based Class 150/1 units. The Manchester units were eventually returned to their original configuration, while the Birmingham-based units were renumbered into the 1500xx range by subtracting 100 from the previous number (e.g., 150103 became 150003). This renumbering provided the operational advantage of an extra set of passenger door controls within the train for the conductor, facilitating easier revenue collection without having to traverse the full length of the unit between stations.

Class 150 units are equipped with BSI couplers, enabling them to work in multiple with Class 142, Class 143, Class 144, Class 153, Class 155, Class 156, Class 158, and Class 170 units, as well as other units of the same class. However, they cannot work in multiple with Class 165 or Class 166 units due to incompatible wiring arrangements.

Initially, the Class 150s had unique interior door open/close buttons: square and blue in northern England, yellow and lit turquoise when enabled in southern Scotland, and bright yellow in southern England. These buttons were designed to aid visually impaired passengers but did not meet later disability standards due to their lack of braille and small size. During the 2000s, these buttons were replaced across the fleet by the standard EAO series 56 'easy to see, easy to press' raised circular door buttons, featuring braille and a yellow surround to comply with the Rail Vehicle Accessibility Regulations.

The NIR Class 450 was built using the Class 150 bodyshell and operated by Northern Ireland Railways. Most of these units were scrapped at the end of their design life in 2014, although two remained.

A single additional unit was constructed specifically for testing duties. Initially numbered in the Class 180 series, this unit is now in the departmental Class 950 series, numbered 950001, and carries the yellow Network Rail livery.

The performance of the Class 150 led British Rail to procure similar trains for the Provincial fleet, such as the Class 156 and Class 158, for longer regional routes. These newer classes replaced a significant portion of the locomotive-hauled stock previously operated by British Rail.

Of the two prototypes, 150002 was less reliable and was therefore chosen as the testbed for the Class 158. It was re-geared for a maximum speed of 90 mph (140 km/h), fitted with Cummins engines and Voith transmission, and received a Class 158 interior. One car was equipped with the Class 151 Twin Disc 'hot-shift' transmission, which proved successful once the control software was optimized. This modified unit was reclassified as the Class 154. It has since been restored to its original configuration and number. Both prototypes remained in service with London Midland until 2011. Unit 150001 entered service with First Great Western in January 2012, followed by 150002 after refurbishment and re-livery. They then operated for Great Western Railway, with 150001 based at Bristol's St. Phillips Marsh Depot and primarily serving the Bristol Parkway-Weston Super Mare route, while 150002 was based at Exeter St. Davids Depot and mainly ran on the Riviera Line alongside Class 143 Pacers. In April 2020, both units were transferred to Northern's Newton Heath Depot and initially used on the Manchester Victoria-Todmorden-Blackburn route, later serving the Rochdale-Manchester-Bolton-Clitheroe services.

Simultaneously, Metro-Cammell built two prototype Class 151 units at its Washwood Heath plant. The two types of units underwent extensive testing to determine which would be more suitable for further orders. These tests demonstrated that the Class 150 had exceptional ride quality and met the 50 percent engine-out performance requirements. As a result, the Class 150 units proved to be more reliable, leading to an order for 50 two-car units from BREL.

Current Operations

Northern England

After the privatisation of British Rail, Class 150/1 and 150/2 units were operated by North Western Trains, which was subsequently taken over by First Group and rebranded as First North Western. Additionally, Arriva Trains Northern also operated these units. The North Western Trains units underwent refurbishment by Hunslet-Barclay in Kilmarnock, while the Arriva Trains Northern units did not receive such upgrades. Upon Northern Rail's takeover, both the former First North Western (FNW) and Arriva Trains Northern (ATN) Class 150 units were transferred to the Newton Heath depot in Manchester. Meanwhile, the former North Western Trains Class 158s were moved to Northern's Neville Hill depot in Leeds. All Northern 150 units were equipped with high-density 2+3 seating.

In late 2011, Northern Rail received several ex-London Midland Class 150/1 and 150/2 units after new Class 172 units entered service in the Midlands. This transfer enabled Northern Rail to increase capacity on its most overcrowded services.

In 2015, the newly established Northern franchise announced plans to reform 24 of their Class 150 units into three-car sets by March 2019. These reconfigured sets were intended for routes including the Penistone Line and Leeds to Goole, though this plan was not ultimately realised.

On 1 April 2020, Northern Trains, the current operator, received the Angel Trains Class 150/0 units, which had previously been leased to Great Western Railway (GWR).

Southwest England

After British Rail was privatised, the fleet passed to Porterbrook who leased the trains to Wales & West, which was later split up into Wessex Trains and Wales & Borders (later Arriva Trains Wales) in 2001.

Great Western Railway currently operates a fleet of 20 Class 150/2 units which are mainly used for services on the local branch lines in Devon. This includes the Avocet Line/Riviera Line between Exmouth and Paignton plus the Tarka Line between Barnstaple and Exeter Central (occasionally, when a Class 158, 165 or 166 isn't available). They are also used on the Cornish branch lines which includes the Tamar Valley Line between Plymouth and Gunnislake, Atlantic Coast Line between Par and Newquay, Looe Valley Line between Liskeard and Looe, Maritime Line between Truro and Falmouth Docks and St Ives Bay Line between St Erth and St Ives.

GWR previously operated the two prototype three-car Class 150/0 units, which had transferred from London Midland and replaced the Class 165 and 166 Turbo units which were being used on the Reading to Basingstoke Line, which allowed the Turbo units to reinforce Thames Valley services. 150001 had entered service in January 2012. The two prototype units later cascaded down to the West fleet in response to the Class 387s taking over from the Class 165s and 166s on the London Paddington to Didcot Parkway services, hence releasing Turbos to take over on the Reading to Basingstoke Line again. Until the end of their operation by GWR, the two 150/0s were based at St Phillips Marsh depot in Bristol and were used on local services around Bristol and Exeter. In April 2020, they transferred to Northern Trains.

Wales

Following privatisation, Wales & Borders continued to use the fleet of Class 150 units on branch-line services as well as on the commuter services around Cardiff known as the Valley Lines and the Vale of Glamorgan Line. The units transferred to Arriva Trains Wales in December 2003, with more later acquired for the reopened Ebbw Vale line. All of the ATW units were transferred to KeolisAmey Wales on 14 October 2018 and all KeolisAmey Wales units were transferred to Transport for Wales Rail on 7 February 2021.

Midlands

Following privatisation of British Rail, both Silverlink and Central Trains operated Class 150s in the midland regions of England and both companies were run by National Express.

In 2010, London Midland ordered Class 172 replacements for its Class 150s. It initially hoped to retain some of the 150s as additional capacity, although they were also wanted by First Great Western and Northern Rail. London Midland was expected to lose all of its Class 150s, but a change in plan saw it retain three Class 150 units as additional capacity, following a statement from the Department for Transport on 10 August 2011. However, London Midland lost two Class 153s to First Great Western as a result.

On 29 April 2019, the Class 150s that were still in operation with West Midlands Trains transferred to Arriva Rail North, having been replaced by Class 230s and Class 172s.

In July 2023, three Class 150/1s, 150137, 150139 and 150141, were transferred from Northern Trains to London Northwestern Railway for use on the Marston Vale line, after the Class 230s in use on the line were withdrawn from use in December 2022 due to maintenance concerns after the company who maintained the units, Vivarail, went into administration. The Class 150s entered service with LNR on 20 November 2023.

Former Operations

Scotland

Upon the privatisation of British Rail, the bus company National Express ran ScotRail, and its successor First ScotRail operated 18 Class 150s out of Edinburgh Waverley on Fife Circle services. Other workings included Dundee and Carnoustie, as well as operating alongside other DMUs such as Class 158s on the Crossrail services between Newcraighall through Edinburgh to Bathgate, Stirling, Dunblane and occasionally Perth. In 2005, 15 were transferred to Arriva Trains Wales and three to Northern Rail.

Eastern England

Anglia Railways was created upon privatisation of British Rail, and it initially inherited a small fleet of nine Class 150/2 units, later supplemented with a tenth. The units were based at Crown Point TMD, and put to use on rural services in Suffolk and Norfolk. Lines using the units included the Bittern Line, the East Suffolk Line, and the Wherry Lines, as well as services from Ipswich to Cambridge. One unit each weekday was sub-leased to First Great Eastern for use on the Sudbury Branch Line.

Anglia Railways named all bar one unit (150245) of its fleet after famous local figures. On 1 April 2004, Anglia Railways became part of the new 'One' franchise. The Class 150 units were transferred to Arriva Trains Wales (no. 150245) and Central Trains (all other units), having been replaced by Class 156 units from Central Trains.

Silverlink/London Overground

National Express operated the North London Railways franchise from 1997 under the Silverlink brand. They had eight Class 150s; seven were cascaded from Central Trains following delivery of new Turbostar units in 2000, to replace the ageing fleet of Class 117 and Class 121 units. The eighth unit, no. 150121, was transferred to Silverlink in late 2005.

London Overground, which took over the North London network in 2007, inherited the eight Class 150/1 units. Six were employed on the Gospel Oak to Barking line, while two were sent on long-term loan to First Great Western.

All units had names, the majority are references to the Marston Vale Line on which they operated during Silverlink's franchise: Leslie Crabbe was a long-standing railway employee, who worked on the route; Richard Crane is the chairman of the Bletchley to Bedford Rail Users Association who has campaigned for the line to be retained and expanded. Three of the names were inherited from the previously incumbent Class 121 units. All the units were then transferred to GWR in 2010 before being transferred again to Arriva Rail North in 2018, and their names are no longer applied.

By the end of October 2010, all London Overground's Class 150/1s had been replaced by a new fleet of eight two-car Class 172 units operating exclusively on the Gospel Oak to Barking Line. Their final use was on 28 October 2010, when unit 150128 formed the 19:02 Barking to Gospel Oak service. The six units were cascaded to First Great Western, together with nine of the London Midland fleet.

Accidents & Incidents

• On 15 December 1987, 150212 collided with an engineer's crane near Seamer West signal box in North Yorkshire.
• On 11 November 1988, 150209 derailed at St Helens Central, Merseyside. The train struck the abutment of an overbridge, crushing the leading cab and killing the driver. Sixteen passengers sustained minor injuries.
• On 12 July 2012, 150217 collided with cattle at Letterston, Pembrokeshire, and was derailed. There were no injuries amongst the 30 passengers and crew on the train.
• On 11 May 2014, 150239 collided with a motorcycle on a level crossing at Frampton Mansell, Gloucestershire, killing the rider.
• On 14 May 2015, two Class 150 units formed a train that collided with an agricultural tractor on an occupation crossing between Knaresborough and Cattal, North Yorkshire. Three people were injured.
• On 7 November 2015, units 150133 and 150204 formed a passenger train that was derailed near Knaresborough due to a signalman's error.
• On 3 April 2016, 150219 collided with a stationary InterCity 125 train at Plymouth. Thirty-five people were injured, and both trains were damaged.
• On 3 September 2017, 150217 collided with a tree near Llanbradach in Caerphilly, Wales, at around 10 pm. Three people were injured and five fire crews were in attendance.
• On 7 February 2018, 150203 divided on the approach to Leeds. There were no injuries, but passengers had to be evacuated across the tracks.
• On 31 January 2019, 150234 derailed at low speed at Penryn shortly before 1 pm. No injuries were reported. A reduced service was run on the line between Truro and Falmouth until the unit was removed.
• On 15 October 2019, 150245 collided with a fallen tree near Spittal, Pembrokeshire and was severely damaged.
• On 27 August 2021, 150271 collided with the outrigger of a crane lorry that was obstructing the line at Penistone.
• On 26 November 2021, 150284 collided with a fallen tree and was derailed at Balderton, Cheshire.
• On 22 May 2022, a train formed of 150240, 150242 and 150279 struck a mini digger near Craven Arms, causing a fuel leak, igniting a fire under one of the carriages. Two units were severely damaged.