British Rail Class 31

Several sub-classes of Class 31 exist:

• 31/0 - First batch of locos, fitted with Red Circle electro-magnetic control equipment[6] - withdrawn in the late 1970s as non-standard. RA 5
• 31/1 - The standard locomotive, fitted with Blue Star electro-pneumatic control.[6] RA 5
• 31/4 - As Class 31/1 but fitted with Brush Electric train heating (ETH) apparatus, index 66.[6] RA 6
• 31/5 - Former 31/4 with the ETH isolated for Civil Engineers Department use. RA 6
• 31/6 - Standard locomotive through wired for ETH but without ETH apparatus. RA 5

D5513, one of the original batch, in BR green livery

These first 20 locomotives, originally numbered D5500–D5519,[7] were always easily recognisable as they did not have the headcode box mounted on the roof above the cab, leading to the nickname "Skinheads". They were also nicknamed "Gurglers" from the noise of their engines, and "Toffee Apples" from the shape of the control key which had to be taken from cab to cab when changing ends. These pilot scheme locomotives were non-standard in having Electro-Magnetic Multiple-Working control equipment, and were limited to 80 mph (130 km/h). After being involved in a serious collision D5518 was rebuilt in September 1967 as a standard locomotive, with indicator boxes, and blue star coupling code

They were allocated to East Anglian sheds throughout their service, ending up allocated to Stratford, their initial shed,[8] and latterly sporting that depot's trademark silver roof. Upon withdrawal four locomotives[9] were converted at Stratford into train pre-heating units. Locomotives 31013, 31002, 31014 and 31008 were renumbered ADB968013 to ADB968016 in the order given;[10][11] ADB968014 was allocated to Bounds Green depot on the Great Northern main line and ADB968015 was based at Great Yarmouth, while the remaining two were allocated to Stratford.

Class 31/1 on Sharnbrook bank with a short van train in April 1985

The first few locos externally had much in common with the original 31/0s as twenty lacked the roof mounted headcode box (D5520–29/35/39/42/47/51/52/55/56/59/62),[12] and fifteen were also limited to 80 mph (130 km/h) (D5520–D5534),[13] but were otherwise the same as subsequent locos. The whole sub-class had steam heating boilers fitted, had the Blue Star Electro-Pneumatic multiple-working controls as found on many other BR classes. The Class 31/1s could be found on a variety of secondary and relief passenger duties as well as parcels and freight traffic. While used in East Anglia, with locos allocated to Stratford and March depots, they were found throughout the Eastern Region of BR with Finsbury Park sporting a large allocation along with the depots at Tinsley, Immingham and Thornaby. Locos were also allocated to Bristol Bath Road and Old Oak Common on the Western Region, where they could be found working passenger trains as far west as Barnstaple and Paignton.[14] In the early 1980s Healey Mills and Bescot on the Midland Region also gained an allocation as replacements for Class 25s.

31418 at Birmingham New Street.

The Class 31/4s, numbered from 31400 to 31469, were conversions of 31/1s to which electric train heating (ETH) was fitted. They had an ETH index of 66, equivalent to 330 kW, which was sufficient to power trains of up to eleven Mk 3 carriages. This allowed them to pre-heat long trains moving between depot and a station for a service to be worked by a larger locomotive. When passenger services were worked 31/4s they rarely exceeded four or five carriages. 330 kW accounted for about a third of the total electrical power output. When ETH was being supplied, the traction power output of the 31/4 subclass was therefore limited to around two-thirds of that of the non-ETH variants; this did not help the performance of an already somewhat underpowered locomotive.

31549 at Peterborough in 1994.

In the late 1980s with increased use of "Sprinter" type units on previously loco hauled diagrams, there were ETH fitted Locomotives to spare and with this in mind, some Class 31s were selected to have their ETH cables removed from the front buffer beam. This was done to try to prevent passenger sectors of BR borrowing the locomotives from the Freight sectors, and to cut down on maintenance of surplus equipment. The re-numbering was achieved by simply adding 100 to the existing TOPS number i.e. 31407 became 31507. When the re-numbering was taking place, most locos were still in standard BR Blue livery and the 4 in the number was painted over and a 5 placed over the top. Some of the sub-class were painted into Civil Engineers all over Grey livery, although most were subsequently painted into the "Dutch" Yellow and Grey livery. Only 31530 (Sister Dora), 31544 (Keighley and Worth Valley Railway) and 31568 (The Engineman’s Fund) were named when numbered as a 31/5. 31544 was also notable as the only one of the sub-class with the original "skinhead" style cabs without the route indicators on the roof.

Only two locomotives (31601 and 31602, formerly 31186 and 31191 respectively [15][16]) received this modification, performed during their time with Fragonset Railways. This modification means they are through wired for Electric Train Heating (ETH) but cannot actually provide it. This means they can be coupled to a train behind another locomotive, and the front locomotive is still able to heat the train via the wiring on the 31/6. 31601 is now preserved at the Ecclesbourne Valley Railway where it regularly operates trains [15] while 31602 was scrapped after being withdrawn.

In 2022 the only operational class 31/4 outside preservation was 31452 which is based at Great Yarmouth.[28][29]

Before the introduction of Class 66, English Welsh & Scottish (EWS) took control of the Class 31s from the Mainline Freight and Trainload Freight companies. 31255 became the locomotive for the EWS livery paint trials but never ran on the main line and spent its life at Toton until being preserved in January 1999. 31466 was repainted into EWS colours for the Toton TMD open day in May 1998 and soon became the only one of the class to be in traffic running in the EWS colours until being preserved in February 2001. In their final days of EWS ownership, 31110 (scrapped at TJ Thompson's, Stockton in April 2007) was repainted into BR green in the summer of 1999 and featured its original number D5528 to mark the end of their working lives with EWS and worked the last EWS Class 31 hauled railtour. The final four EWS locomotives were withdrawn in February 2001. Of the two EWS liveried locos, both 31255 and 31466 are preserved, 31255 based at the Mid Norfolk Railway[30] and 31466 based at the Dean Forest Railway.

Locomotive 31454, in InterCity Swallow livery (with Fragonset Vinyls) on 16 April 2004

In 1998, Fragonset Railways purchased four redundant Class 31 locomotives from EWS. The first of these, 31452, was quickly repaired and repainted in a new black livery with a red mid-body band. It was quickly followed by 31459 and 31468. Several more locomotives were also purchased, and in 1999, the first of two modified Class 31/6 locomotives re-entered traffic. The Class 31/6 31601 (ex 31186) & 31602 (ex 31191) subclass is essentially a modified Class 31/1 locomotive with through electric-train heating wiring. This enables a Class 31/4 and Class 31/6 to work in multiple and still heat the train, even if the no-heat Class 31/6 is attached to the carriages.

In 1999, Fragonset won a short-term contract with Silverlink for two locomotives to work in top and tail mode with two Mk. 1 carriages on the Marston Vale Line. This was to cover for the non-availability of Class 117 and Class 121 diesel multiple units. The trial was a success, and in 2000 it was repeated in the summer timetable. The locomotives were retained until displaced by more modern Class 150/1 units cascaded from Central Trains.

By this time, the Fragonset Class 31 fleet had expanded considerably to include three Class 31/1s, three Class 31/4s and two Class 31/6 locomotives. Regular work at this time included use hauling Class 317 electric multiple units from West Anglia Great Northern's Hornsey depot to Bedford for use with Thameslink. As units were still maintained at Hornsey, this meant regular workings between the two depots to swap units when maintenance was due. 31468 was broken up for spares, finally being scrapped 6 June 2018.[31]

Created in 2018, in 2022 Hanson and Hall had one of the three remaining operational Class 31s outside preservation. 31106 was stored at Bury on the East Lancashire Railway in Rail Blue livery.[29]

After the demise of FM Rail, several of its Class 31s passed to Mainline Rail, operated by RMS Locotec. As of November 2008, four 31/4s and one 31/6 are owned by RMS Locotec, which is a subsidiary of British American Railway Services.

31128, an ex-Fragonset locomotive, is owned by Nemesis Rail and based at Burton upon Trent. In 2022 this locomotive is one of only three remaining operational Class 31s outside of preservation, and has been returned to BR Blue livery.[29]

31105 passes Chesterfield working 4Q25 Derby RTC - Immingham TMD Test train

Network Rail operated a fleet of four Class 31 locomotives – 31105, 31233, 31285, and 31465 – to haul test trains around the network. The locomotives were purchased from Fragonset Railways, and overhauled at its Derby workshops. They were repainted in Network Rail's then new all-over yellow livery. 31285 and 31465 were offered for sale by tender in July 2015,[32] and 31233 and 31105 in August 2018.[33]

Prior to operating its own locomotives, Network Rail's predecessor, Railtrack, had hired two Class 31 locomotives from Fragonset. These two locomotives, 31190 and 31601, were repainted in Railtrack's blue and lime green livery. With the overhaul and entry into service of Network Rail's own locomotives, these two engines were returned to Fragonset. (They are now owned by British American Railway Services, based at Washwood Heath in Birmingham.)

Locomotive 31106, formerly Spalding Town, is privately owned by Howard Johnston, and after a period of lease to Fragonset, FM Rail, and RVEL which included extensive main line running for 11 years, including working as far north as Oban in Scotland, is based at the Weardale Railway. After inspection, it was successfully started on 17 October 2017 and moved under its own power for the first time in four years. Johnston purchased three more of the class from EWS, but they acquired new owners; 31107 (scrapped by C F Booth at Rotherham in May 2009, following a staged collision with a Renault Espace on a level crossing during Top Gear Series 9, Episode 5 in 2006), 31289 (preserved at the Northampton and Lamport Railway), and 31301 (scrapped).

The last active Network Rail Class 31 was 31233, with it operating its last test trains in March 2017. In August 2018, Network Rail offered its final two Class 31s (31105 and 31233) for sale; both were purchased for preservation at Mangapps Railway Museum in Essex .[33]

31 members of the class have survived into preservation. This number includes both the first and last produced (31018 and 31327, respectively). There were a further 10 which have subsequently been scrapped.

Note: * = "skinheads"

In addition, the following locomotives were previously preserved, but have since been scrapped.

• 31113 ex-Chinnor and Princes Risborough Railway - scrapped in June 2008 at EMR Kingsbury after death of owner
• 31123 ex-Gloucestershire Warwickshire Railway - scrapped in February 2006 by A1A Locomotives
• 31144 ex-Weardale Railway - scrapped in January 2014. Both cabs preserved by the South Wales Cab Group, Bridgend.
• 31166 ex-Wensleydale Railway - scrapped in June 2009
• 31188 ex-Wensleydale Railway - scrapped in September 2008
• 31410 ex-Stainmore Railway - scrapped in September 2014 at CF Booths Rotherham
• 31421 ex-Midland Railway Butterley - scrapped in August 2007 after deal fell through for loco to get power unit ex. 31405
• 31442 ex-Churnet Valley Railway - scrapped in September 2004
• 31467 ex-East Lancashire Railway - scrapped in August 2008 after being stripped by metal thieves.
• 31468 ex-Weardale Railway - scrapped in June 2018.
• 31556 ex-East Lancashire Railway - scrapped in January 2010.

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• Stevens-Stratten, S.W.; Carter, R.S. (1978). British Rail Main-Line Diesels. Shepperton: Ian Allan Ltd. ISBN 978-0-7110-0617-1.
• Strickland, David C. (September 1983). Locomotive Directory: Every Single One There Has Ever Been. Camberley: Diesel and Electric Group. ISBN 978-0-906375-10-5. OCLC 16601890. OL 27959920M. Wikidata Q105978499.
• Toms, George (1978). Brush Diesel Locomotives, 1940-78. Sheffield: Turntable Publications. ISBN 978-0902844483. OCLC 11213057.
• Williams, Alan; Percival, David (1977). British Railways Locomotives and Multiple Units including Preserved Locomotives 1977. Shepperton: Ian Allan Ltd. ISBN 978-0-7110-0751-2.