British Rail Class 423 (4 VEP)
Class 423/1 4 VEP 3427 at Eastleigh in 2001
In service	1967 – 26 November 2005
Manufacturer	British Rail
Orderno.	30758 (DTCsoL, 76230-76269) 30759 (TSO, 70781-70800) 30760 (MBSO, 62121-62140) 30771 (DTCsoL, 76333-76402) 30772 (TSO, 70872-70906) 30773 (MBSO, 62182-62216) 30792 (DTCsoL, 76441-76540) 30793 (TSO, 70907-70956) 30794 (MBSO, 62217-62266) 30799 (DTCsoL, 76541-76560) 30800 (MBSO, 62267-62276) 30801 (TSO, 70957-70966) 30811 (DTCsoL, 76641-76716) 30812 (TSO, 70997-71034) 30813 (MBSO, 62317-62354) 30851 (MBSO, 62435-62475) 30852 (TSO, 71115-71155) 30853 (DTCsoL, 76861-76942)[1][2]
Built at	York Works Derby Works
Number built	194
Formation	4 cars per trainset: DTCsoL+MBSO+TSO+DTCsoL[2]
Diagram	ED261 (MBSO) ED262 (MBSO) ED263 (MBSO, facelifted) ED266 (MBSO, facelifted) EE365 (DTCsoL) EE366 (DTCsoL) EE367 (DTCsoL) EE368 (DTCsoL) EE373 (DTCsoL, facelifted) EE281 (DCTsoL, modified) EH276 (TSO) EH278 (TSO) EH283 (TSO) EH291 (TSO, facelifted)[1][2][3]
Design code	4 VEP[4]
Fleet numbers	7701-7894 (sets, as built) (42)3001-(42)3194 (sets, 423/0) (42)3401-(42)3591 (sets, 423/1) (42)3801-(42)3812 (sets, 423/1) (42)3813-(42)3844 (sets, 423/8) (42)3901-(42)3919 (sets, 423/2) 76230-76942 (DTCsoL) 62121-62475 (MBSO) 70781-71155 (TSO)[2][5]
Capacity	42F/280S (as built)
Operators	British Rail InterCity Network SouthEast Connex South Eastern South Eastern Trains Connex South Central Southern South West Trains
Depots	Bournemouth Brighton East Wimbledon Eastleigh Fratton Ramsgate[1][6]
Specifications
Car length	66 ft 7 in (20.29 m)
Width	9 ft 3 in (2.82 m)
Height	12 ft9+1⁄4 in (3.893 m)
Doors	Hinged slam
Maximum speed	90 mph (145 km/h)[7]
Weight	157.5 t (155.0 long tons; 173.6 short tons) (as built)
Traction motors	EE507
Power output	1,000 hp (750 kW)
Electric system(s)	750VDCthird rail
Current collection	Contact shoe
Coupling system	Drop-headbuckeye[8]
Track gauge	4 ft 8+1⁄2 in (1,435 mm)standard gauge

TheBritish Rail Class 423 (4 VEP),electric multiple unit passenger trains were mostly built byBritish Rail (BR) atYork Works from 1967 to 1974, although theMBSOs and TSOs of the first 20, 7701-7720, were built atDerby Works. They have manually opening doors next to every seating row and were the last coaching stock built in this pattern for BR. They were mostly found working outer-suburban services inSouth London and rural services inKent,Sussex andHampshire, up to 2005 when they were finally replaced byElectrostar andDesiro units. The fleet had a working life of 38 years.

This sectiondoes notcite anysources. Please helpimprove this section byadding citations to reliable sources. Unsourced material may be challenged andremoved.(January 2024) (Learn how and when to remove this message)

Ordered in 1965, 194 standard four-car 4 VEP units were built between 1967 and 1974, numbered 7701-7894; subsequently becoming class 423 underTOPS. They were subsequently renumbered in the 1980s into the 30xx and 31xx series in order to make numbers TOPS compliant. Between 1988 and 1995 the units were internally facelifted. The work involved fitting fluorescent lighting and public address equipment, and also rebuilding the MBS (motor brake second) vehicles with an additional two bays of seating in space formerly used for luggage. On refurbishment only the first 20 units were renumbered in order, in the 34xx series. All other units were renumbered from 3421 onwards, in the order they were refurbished. All units ended up swapping motor vehicles on refurbishment - the additional work on these cars made the work take longer than that carried out on trailer vehicles.

In 1968, due to a shortage of suitable stock for theBournemouth electrification scheme, BR formed an eight-carriage8 VAB unit, no. 8001. The unit was formed of carriages from three standard sets, nos. 7739/41/42, plus a conventional locomotive-hauled buffet carriage. Three MBSOs were required within the make-up as the standard 'TRB' was not through-wired for traction power distribution. In view of this the two MBSOs in the five-car portion had collector shoes fitted to one bogie on each. The unit worked on occasions with a4TC; this usually had aClass 33 attached to provide ETH and train lighting in the TC unit, as the 8 VAB was not fitted with ETH jumper cables on the unit ends. Its normal running formation was with another 4 VEP to make a 12-car set. The 'TRB' vehicle retained its gas-powered appliances so, unlike4 REP buffet cars, was able to provide hot food and beverages while on diversions away from third-rail areas. Adjacent MBSO 62203 had most of its doors locked out of use and tables fitted across them for the service of meals on a 2-and-2 basis (across seats intended for five persons normally); this vehicle also had most of its luggage racks removed. The unit was later reclassified asClass 480 following the introduction ofTOPS.

The numbering of individual vehicles are shown in the table below.

The unit was disbanded in 1974, following deliveries of 4 REP stock, but one of the original units, no. 7739, was not reformed, as spare vehicles from the unit had replaced crash-damaged VEP vehicles in the meantime.

In 1978 12 units, nos. 7788-7799, were fitted with extra luggage racks by removing the squabs and cushions from certain seats and reclassified asClass 4274 VEG units. The units were renumbered into the range 7901-7912 in the same sequence. These units were dedicated to theGatwick Express services fromLondon Victoria toGatwick Airport. Externally these units were marked by an orange/yellow (dayglo) coloured band at cantrail level with lettering 'London-Gatwick express service'. They were used on Victoria to Bognor Regis services attached at the rear from Victoria and detached at Gatwick Airport so that airline passengers did not have to rush to get off the train. The unit then attached to the front of an Up Bognor Regis service back to Victoria.

In 1984 they were replaced on this service byClass 73 electro-diesel locomotives operating inpush-pull withClass 488 coaching sets andClass 489 luggage vans. The twelve units were then converted back to standard sets, and regained their original unit numbers.

The numbering of individual vehicles and details of when units were built are shown in the table below.

Following theprivatisation of British Rail the three southern train operators all inherited large fleets of 4 VEP units. A franchise commitment of all operators was to replace all of the units, along with all other Mark 1 rolling stock, by the end of 2005, as the units did not meet modern health and safety requirements. The fleet of each franchise is described below.

South Eastern Trains operated the largest fleet of 4 VEP units. The franchise was originally operated asConnex South Eastern, which lost the franchise in 2003. The fleet contained several unusual units, including no. 3473, which contained a driving trailer with the compartments removed, and no. 3582, which contained former 4TC driving trailer 76275.^{[citation needed]}

Many units survived into 2005 because of the closure of the Folkestone—Dover section of railway for tunnel refurbishment. This ended in September 2005.^{[citation needed]} The final passenger service was operated on 7 October 2005,^[9] using units 3565, 3545 and 3568.^{[citation needed]}

All the South Eastern Trains 4 VEP units are withdrawn. One driving trailer from unit 3568, and another from unit 3545, have been claimed by theNational Railway Museum, and the former 4TC driving trailer from unit 3582 have been preserved.^{[citation needed]}

This sectiondoes notcite anysources. Please helpimprove this section byadding citations to reliable sources. Unsourced material may be challenged andremoved.(January 2024) (Learn how and when to remove this message)

TheNetwork SouthCentral division inherited a fleet of 50 standardClass 423/1 units. The franchise was originally won byConnex South Central, which soon applied its yellow and white livery to the fleet. However, following poor levels of service and financial mismanagement, the franchise was transferred to South Central Trains in 2000, which was later renamed asSouthern in 2004. Only one unit, no. 3514, was ever repainted in Southern's green livery.

In 1998-1999, whilst still under the control of Connex, 19 units were modified to operate inner suburban South London "Metro" services. The work involved removal of internal compartments and declassification of first class seating. The units were reclassified asClass 423/9, or4 VOP, and renumbered in the range 3901-3919. Due to the lack of first class seating and toilets, these units were generally not used on long-distance services.

In 2003, with the general run-down ofslam door trains, it was decided to reform some of the 4 VOP units by swapping one driving trailer with that from a standard unit, the standard units gaining the ex 4 VOP driving trailer. The new hybrid units were reclassified asClass 423/8 (or4 VIP) and renumbered in the range 3813-3844. This was to give all units some first class seating, thus making diagramming of units easier. But in the event only eight units were reformed, namely nos. 3813/14/21/22/41-44.

By 2004 Southern had started to introduceClass 377 "Electrostar" units into service. Although first introduced in 2002, this did not initially affect the Class 423 as the older 'Phase 1'Class 421 4 CIG units were withdrawn first, due to their age and lowerseating capacity. However, as more new units entered traffic, the first Class 423 units were withdrawn. Units selected for withdrawal were usually those with high mileage or in poor condition. By mid-2005 only a handful of units remained in traffic. The final diagrammed passenger service out of London was the 17:17 London Victoria toEastbourne andSeaford on 19 August 2005, formed of units 3486 and 3535, plus 4 CIG unit 1866. Six units were subsequently retained for emergency cover. Unit 3514 was used on the Sussex Slammer railtour on Saturday 19 November 2005.

The following Saturday saw the final slam door trains on Southern, when units 3490, 3505 and 3535 formed the 09:19 Brighton to London Victoria and 11:06 London Victoria to Brighton services (via Lewes due to engineering works); this being the last scheduled mainline passenger service using southern-electric slam-door stock (the very last passenger being an off-dutyHM Inspector of Railways). Following this trip the stock was withdrawn from service and initially put into Lover's Walk depot before being moved (under its own power) to Battersea Stewart's Lane Depot (road 12) from where it was hauled away at 12:26hrs on 3 January 2006 by aclass 47 locomotive for scrapping.

One complete 4 VIP unit has been preserved, and two 4 VOP units remained in departmental use until March 2013.

This sectiondoes notcite anysources. Please helpimprove this section byadding citations to reliable sources. Unsourced material may be challenged andremoved.(January 2024) (Learn how and when to remove this message)

South West Trains (SWT) inherited the second-largest number of units, with an initial fleet size of 62 units. The entire fleet was composed of standardClass 423/1 units. Later, a further four units (nos. 3809-3812) were transferred from Connex South Eastern. These were also standard units, but were numbered in the 38xx series to denote they were leased fromPorterbrook rather thanHSBC Rail.

SWT quickly repainted its fleet of units into a new livery, based on the previousNetwork SouthEast (NSE) livery, but with the addition of an orange stripe and the absence of the grey band. All but four units (3415 and 3809–3811) were repainted. These four units were deliberately retained in NSE livery, meaning that in the final days of slam-door trains they attained "celebrity" status amongrail enthusiasts.

In 2001, SWT placed an order for 785 new carriages withSiemens to allow it to replace its fleet of slam-door trains, in accordance with its franchise commitment to do so by 2005. To assist Siemens in the design ofthird rail units, 4 VEP no. 3810 was transferred to a test site in Germany to undergo tests. Following its return to Britain, it became popularly known as the "Great Escape".

South West Trains started to replace its slam-door fleet from early 2004, with the introduction of the firstClass 444 andClass 450Desiro units. Around this time, SWT repainted one unit, no. 3417, into its originalBR Blue livery to commemorate the final months in traffic of the slam-door fleet. This unit was chosen because it was one of the last to receive major works attention, and therefore had the longest life-expectancy. It was namedGordon Pettitt after a former manager of theSouthern Region of British Railways.

In the final months of traffic several units, including the first-built, no. 3401, were reformed in order to allow the vehicles in the best condition to be retained in service. Withdrawals of units picked up pace, with several large culls of units, the last of which occurred in March 2005. Beyond this date, only a handful of units remained in traffic, namely nos. 3401/17/81 3516/20/36/76 and 3811. The final normal passenger service was operated on 26 May 2005 fromLondon Waterloo toBournemouth, using 4 VEP 3536 sandwiched between4 CIG units 1396 and 1398. Following withdrawal, most units were rapidly towed away for scrap. The "celebrity" blue unit, no. 3417, has since been sold to theBluebell Railway.

This sectiondoes notcite anysources. Please helpimprove this section byadding citations to reliable sources. Unsourced material may be challenged andremoved.(January 2024) (Learn how and when to remove this message)

Following withdrawal from normal service, several vehicles have seen further use in departmental service.

• 4 VOP units 3905 and 3918 were converted into tractor units. They were used to haulClass 375 units to and fromAshford Works.
• MBSO 62138 (ex-unit 3567) was renumbered to 977981 and was used as a motor coach in theHitachiV-Train no. 960201 duringthird-rail testing. It has since been scrapped.

• On 26 January 1985, units 7754 and 7703 formed a train with 4 CIG unit 7395 which was halted by a landslip atPopham, Hampshire and was run into by Class 33 locomotive 33 104 due to the traincrew failing to protect the rear of the stranded train. Twelve people were injured. The Class 33 was written off.^[10]
• On 6 November 1985, unit 7724 collided with 4 CIG unit 7390 at Copyhold Junction, nearHaywards Heath,West Sussex due to a lack of braking and poor rail adhesion. Forty people were injured.^[10]
• Main article:Clapham Junction rail crash
  On 12 December 1988, a train comprising units 3033, 3119 and 3005 formed the 07:18Basingstoke -Waterloo service which was run into by the 06:14Poole - Waterloo service, formed of 4 REP unit 2003 and 4TC units 8027 and 8025 atClapham Junction. An empty stock working comprising units 3004 and 3425 running in the opposite direction on an adjacent line was struck by the derailed trains. Thirty-five people were killed, nearly 500 were injured.^[11][12]
• Main article:Purley rail crash
  On 4 March 1989, unit 3441 is run into by a passenger train comprising 4 CIG units 1280 and 1295, which hadoverrun signals atPurley,Surrey. Five people were killed and 88 were injured.^[13]
• On 1 August 1990,Class 119diesel multiple unit L576 collided with a passenger train comprising 4 VEP units 3508 & 3504, and 4 CIG unit 1304 atReading due tooverrunning signals. Forty people were injured.^[14]

So far two complete units (highlighted in table below) and two individual driving trailers have been preserved. In addition the former 4TC driving vehicle from set 3582 has been preserved.

The more high-profile unit preserved is the former South West Trains (SWT) "celebrity" unit painted in BR blue livery with painted aluminium window frames, no. 3417. The unit was initially used on Wimbledon depot as ashunter, but with SWT needing to get it off its books it was sold to theBluebell Railway for the nominal sum of £1. It was moved to Eastleigh Works for storage, after having been used initially as the centrepiece for the Bluebell in a ceremony atEast Grinstead railway station to mark the commencement of work at the station site as part of the line's work on the northern extension. The unit returned to East Grinstead for further use and storage in September 2010. In late April, the unit sustained minor damage to its shoegear as it was being driven from sidings at Clapham Junction Yard prior to movement under tow to theSwanage Railway. This resulted in the traction current being discharged in the yard whilst repairs were carried out. The unit was then moved back into the sidings and then dragged to Swanage the following day. The unit was for some time stabled in the open at Clapham Junction, having previously been stored in the shed at the yard. The unit was then moved to Ilford as part of a deal brokered by the unit's support group for a full repaint. After the completion of this bodywork restoration, it was transferred to Strawberry Hill in South West London where the interior underwent long-term refurbishment by volunteers from the Southern Electric Traction Group. It was returned to the National Rolling Stock Library on 16 January 2024.^[15]

The second set, no. 3905, was turned into a tractor unit before being used for spares by the 5 BEL Trust to restore a5 BEL set. It was donated for preservation and was stored at theDartmoor Railway. In 2016 the termination of lease by Dartmoor Railway meant the unit would leave the railway and find a new home at theEast Kent Railway in Sheperdswell.

One other set, no. 3822, was briefly preserved until 2010 when it was scrapped. It was located at theChurnet Valley Railway and was partially restored. In 2008 half of the set was returned to as-built BR Blue and received internal repairs. The other half remained in "as withdrawn" Connex condition, and the set operated at several special events throughout that year.

There was an attempt to preserve unit 3810 (the unit that was briefly exported to Germany), but this failed and ultimately it was scrapped.

Original-condition units

Facelifted units

Hornby produce the 4 VEP model inOO gauge. The model represents the main 2 variations:

1. Original units - with the full brake area in the MBS;
2. Refurbished units - as undertaken from 1988 onwards, with a reduced brake compartment replaced with extra seating bays.

• Fox, Peter (1987).Multiple Unit Pocket Book. British Railways Pocket Book No.2 (Summer/Autumn 1987 ed.). Platform 5 Publishing Ltd.ISBN 0906579740.OCLC 613347580.
• Fox, Peter (1994).Electric Multiple Units. British Railways Pocket Book No.4 (7th ed.). Platform 5 Publishing Ltd.ISBN 9781872524603.
• Longworth, Hugh (2015).British Railways Electric Multiple Units to 1975. Oxford Publishing Co.ISBN 9780860936688.OCLC 923205678.

Wikimedia Commons has media related toBritish Rail Class 423.

• Marsden, Colin J. (1982).EMUs. Motive Power Recognition. Vol. 2. Ian Allan. pp. 98–105.ISBN 9780711011656.OCLC 16537600.

• British Rail electric multiple units
• Train-related introductions in 1967
• 750 V DC multiple units

• CS1: unfit URL
• Articles with short description
• Short description is different from Wikidata
• Use dmy dates from January 2017
• Use British English from January 2017
• All Wikipedia articles written in British English
• Articles needing additional references from January 2024
• All articles needing additional references
• All articles with unsourced statements
• Articles with unsourced statements from October 2020
• Commons category link is on Wikidata