British Rail Class 143

Class of diesel multiple unit trains, part of the Pacer family of trains

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| numberbuilt = 25
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| numberpreserved = 13
| numberscrapped = 12
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| formation = 2 cars per unit: DMS (Driver's cab, Motor car, Standard class saloon) DMSL (Driver's cab, Motor car, Standard class saloon, Lavatory)|In 5 abreast config. : 122 seats|(one per vehicle)
| enginetype = Inline 6 4 stroke turbo diesel
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| brakes = Electro pneumatic (tread) except where otherwise noted. The British Rail Class 143 is a diesel multiple unit railbus, part of the Pacer family of passenger trains introduced between 1985 and 1986. 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, leading to an initial production batch by British Leyland, designated Class 141 units. BR, seeking to procure improved derivatives of the Class 141, placed an order with the manufacturers Hunslet Barclay and Walter Alexander to construct its own variant, the Class 143. Entering operational service during the mid 1980s, the Class 143 embodied several advances over the original model in terms of ride quality and reliability. During its operating lives, the type operated various passenger services across the United Kingdom; initially operated in the North East of England, all units were subsequently transferred to other regions, including Wales and South West England. Due to their non compliance with the Rail Vehicle Accessibility (Interoperable Rail System) Regulations 2008, the Pacer family began to be withdrawn during the late 2010s ahead of the 1 January 2020 deadline. Some fleets were given dispensation to operate until 31 December 2020. While modifications for compliance were proposed by rolling stock companies, no train operator took up the option. Great Western Railway retired its Class 143 fleet in December 2020, while Transport for Wales was granted an extension and ran its trains until 29 May 2021.

On 17 October 2004, Wessex Trains unit 143613, forming a service from to with 143621, caught fire between the site of the former Flax Bourton railway station and Fire services took two hours to get the blaze under control. Of the 23 passengers and crew, three were treated on site for the effects of smoke inhalation. One carriage was completely burnt out, and the other was badly damaged, causing the train to be written off. The line through Nailsea was closed until 03:30 the following morning, when the train was hauled to St Philip's Marsh depot for examination. The unit was later taken to Crewe Works where it was stored, then later to Cardiff Canton TMD where it was scrapped. The Rail Safety and Standards Board issued a report into the incident, concluding that the fire was caused by electrical arcing between the live starter motor cable (which had damaged insulation) and the unit's underframe, causing accumulated oily residues to ignite. On 16 January 2020, 143603 had several windows smashed in by waves and sea debris while running along the sea wall at Dawlish during stormy weather, causing minor injuries to one passenger.

ClassStatusQty. Year builtCars per unitUnit nos.143Preserved111985–19862143601–143603, 143606, 143612, 143616–143619, 143623, 143625Scrapped12143604–143605, 143608–143611, 143613–143615, 143620–143621, 143624 pending transfer to Vale of Berkeley Railway. 1436065564755672Arriva Trains Wales (unbranded)Llanelli & Mynydd Mawr RailwayArrived 3 June 2021. 143612 5565355678Great Western RailwayLlanelli & Mynydd Mawr RailwayArrived April 2022.1436165565755682Arriva Trains Wales (unbranded)Tanat Valley Light RailwayArrived 7 July 2021.1436175564455683Great Western Railway Tarka Valley RailwayArrived 16 November 2022. Named after Founder Member and Chairman Rod Garner on 8 April 2023.1436185565955684Plym Valley RailwayDonated to the Plym Valley Railway in 2022.1436195566055685Tanat Valley Light RailwayArrived August 2022.1436235566455689Regional RailwaysWensleydale RailwayReturned to traffic in summer 20231436255566655691Arriva Trains Wales (unbranded)Keighley and Worth Valley Railway—

Alongside the operational preserved Class 143s, some have been acquired for non operational use at heritage railways or for non railway use. UnitVehicle numbersLiveryLocationNotesDMSDMSL1436075564855673Arriva Trains Wales (unbranded)Llanelli & Mynydd Mawr RailwayArrived 3 June 2021. To be converted for use as a ticket office, shop, and café for the railway. 1436225566355688Llanelli Goods ShedArrived June 2021, as part of the refurbishment of the goods shed.