4-DD EMU History

O.V.S.Bulleid - Chef Mechanical Engineer (CME) of the Southern Railway (1937 - 1948)

Oliver Vaughan Snell Bulleid was born in New Zealand during 1882. He came to live in Wales in 1889 following the death of his father. In 1901 he joined the Great Northern Railway and became an Apprentice under H.A.Ivatt the then CME of the railway, In 1908 he became a Test Engineer with the Westinghouse Electric Corporation working his way up, finally becoming Assistant Works Manager and Chief Draughtsman. He also married the daughter of H.A.Ivatt.

Working for the Board of trade for a brief period from 1910 allowed him to travel throughout Europe getting to know Gresley, Stanier and Hawksworth amongst others. This led in 1912, to his rejoining the GNR to work as Personal Assistant for Nigel Gresley. The war however meant him having to join the British Army where he became Major in the rail transport arm. The GNR took him back after the war as Manager of the Wagon and carriage Works.

Upon grouping in 1923 he again became Assistant to Gresley who was now CME of the LNER. He was offered the post of CME of the Southern Railway in 1937, which he accepted at the salary of £3000 per year.

Well known for his experimental work on steam (Merchant Navy, West Country and Battle of Britain locomotives). He was also forward looking and played a major role in the electrification of the Southern network. Designing the electric locomotives CC1 and CC2 (a third was built by BR in 1948), plus of course the 4-DD double deck EMUs.

With the onset of British Rail in 1948 he was influential in the early stages of the Mk1 coach design.

1950 and Bulleid was appointed CME of CIE (Coras Iompair Eireann), retiring in 1958. OVS finally passed away in Malta on 25 April 1970 at the age of 87.

Overcrowding - A Solution

After the war overcrowding on the Southern commuter services into London, especially from Dartford needed a solution. Extending platforms would have cost an estimated £10million. Bulleid came up with the plan for a Double Deck train to increase capacity. The increase in height however severely restricted the routes that could be taken by the trains thus the trials took place on the Charing Cross to Dartford (and Gravesend) lines.

From the Brighton Evening Argus, February 7 1949.

A full scale plywood model of a type of carriage that may one day revolutionise railway travel is nearing completion at the Lancing Carriage works.

It follows months of work by draughtsmen who have been experimenting with a design which may help railways to overcome the problem of rolling stock.

The "Two-in-one" carriage is an idea which may take years to fulfil, It is in the infancy stage, according to railway officials who are loath to talk about it.

In fact the model making at lancing appears to be as secret as the latest development of automic research. No one there will talk of the double-decker carriage.

Top officials say "Sorry. No statement. Not allowed to say anything" and lesser officials, with furtive, over the shoulder glances say "We mustn't say anything, but we have seen it and it looks as if the idea is pretty good".

Despite the secrecy, the model has been built, and it looks as though the Railway executive are greatly interested in the possibilities of "up and down" railway travel.

Pathe Films. Display at Marylebone Station of a mock up of a compartment. (Click picture to play).

The Units

Two units were constructed. The frames built at Lancing and some of the bodywork at Eastleigh. Coaches 1300x were Motor Brake Seconds (MBS), 1350x were Trailer Seconds. Unit 4001 was completed September 1949, 4002 out shopped the following month had cast trailer wheels. The trailer coach bodies were on 62ft under frames, the motor coaches being 6" longer. Behind the driver in each motor coach was a guards brake which was 9' 2" wide. The doors to the brake compartment were inset. Each unit weighed 136 tons.

The motor coaches were built to SR Diagram 2128, the trailers to Diagrams 2020 and 2021, different numbers reflecting buffing and jumper box variations. They were fitted with screw couplings and side buffers at the unit ends, with central buffer and three link couplings within the unit. roller blind headcode boxes were installed.

Below: The Bolsterless bogie, a trailor wheelset and the design team at Lancing.

The under frames were of deep girder construction, which along with the bolster less bogies and smaller wheels allowed more body space within the loading gauge. Sole bars were specially designed to be 9" below the passenger accommodation, but increased to 15" at the guards and motormans compartments to allow for conventional buffer heights.

The units had lightweight 250hp EE507 motors with EP control gear. Brakes were Westinghouse EP self-lapping which were unique to the 4-DDs which meant they were not able to be worked in multiple with other classes. (The EP brake equipment was experimental and had previously been fitted to 6-PUL 3016 and 6-PAN 3034 in 1947/8). The motor bogies had non standard 8ft frames, with wheels 3ft in diameter which was 2" smaller than normal. Top speed was 75mph.

Standard air whistles were fitted on the cab ends when new. Latter they were replaced by two tone horns on the roof. 27 Way control jumpers were fitted (as opposed to the separate lighting and control jumpers on previous units). The jumper was located centrally under the headcode indicator. Problems with miscoupling the jumpers lead to them being relocated to under the secondmans observation window. Standard Power Jumpers were fitted.

Load testing took place at Lancing, the Motor coaches failed with the frames going into reverse camber. Alterations to the structure took place; the roofs were cut across at the centre solebars cut at the bottom flange and a vee cut up to the web to the top flange. Truss bars then cut through each motor coach was jacked up until the required alignment was reached. Solebars and truss bars welded up with stiffening plates and finally the holes in the roof were welded up.

Trials took place on the line between Brighton and Haywards Heath, this showed up some a number of problems and both units had extensive modifications between 22 November 1949 and 6 January 1950. Transfer to Slade Green (then known as Slades Green) occurred on 19th September for clearance tests in the suburban area.

Although called "Double Deck" the internal layout was totally unlike that of a double deck bus. Each compartment could seat eleven six on one side and five on the other. The missing seat on one side was replaced by the steps up into the upper compartment. The upper level also had two tip up seats situated where the door would normally be. Motor coaches could seat 120 (110 plus 10 tip-up). Trailer coaches seated 156 (66 (plus 12 tip-up)) on the upper level and 78 on the lower. The centre compartments on the lower level could seat 12 as there was no upper deck accessible from these.

The train was 4.5" higher (12ft 9") than normal commuter trains and was thus severely restricted on what routes it could run, both in service and on trips to the works at Eastleigh and Lancing. Extra room inside was gained by having straight sides, slightly smaller diameter wheels and by making the seating cushions less padded (4" less padding then a 4-SUB). The seats were also narrower at 16.5" (normally 18.5"). More space was saved by the use of specially made filament lamps that were often mistaken for fluorescent tubes. The lamps were in fact 70 volt tubular opalescent lamps that were mounted in the plywood seat partitions above the heads of the passengers.

The upper windows did not open as there was not sufficient clearance, thus the unit could get very hot in summer. Forced air ventilation was installed to try to get over this. Equipment to power this ventilation system was located in a cupboard beneath the large centre windows of each upper level compartment, and drew air from below the train and supplied it beneath the feet of passengers in the upper level compartments. The ventilation system was thermostatically controlled and under the overall control of the guard. Passengers often avoided the upper deck and often stood downstairs. The doors were flat, not having the camber of normal trains. Each door had a droplight with a quarter light above. Passenger communication was via a value situated above each door, there was no provision for an alarm in the upper compartments.

In Service

The units were introduced to service 1st November 1949 the first train was filmed by Pathe News. The Top Brass from British Railways Board were present along side senior Southern Region officials and members of the Transport Ministry.

When first delivered the units were in Southern Railway Malachite Green with black ends to the coaches and the under frames, the roof painted silver. There was no ownership markings, coach numbers placed on the left hand of the body sides. In 1958 at Lancing the now BR standard BR(S) darker green livery was applied along with the BR Lion and Wheel emblem on the side of the motor coaches. The livery was further adapted with small yellow panels on the driving ends upon the next overall at Eastleigh (1965), then full yellow ends appeared in 1968. The units were finally painted into all blue livery 28th September 1970 when they were also renumbered 4901/2 in order to release the fleet numbers for use on the experimental PEP units. They were always based at Slade Green Depot though out their life.

Below left. 4001(13002), Cannon Street 1963. © Phil Rogers Collection.

Above right:4002 at Waterloo East, March 1967. © David Elliot.

The original intention of increasing capacity was not what happened in reality, the two units seated 1104 plus standing room as well. However the number of doors restricted the time taken to load/unload, each door now serving 24 as opposed to 12 in other suburban units. It was estimated that they extended platform loading and unloading times by as much as 36 per cent. Passengers also tended to try to avoid the upper deck would rather stay standing by the doors. There were also reports of an increase in accidents as the units had no footboards or external handles.

From the Railway Magazine, January 1951:

"Double-Deck Train Trial Results

The Railway Executive has decided that the experimental eight-coach double-deck train, which has been in service on the electrified London suburban lines of the Southern Region for the past 12 months, does not offer a satisfactory long-term solution of the problem of peak-hour congestion. The conclusion reached from the trials is that the public interest and operating efficiency will be better served by longer trains (ten coaches instead of eight) of normal type but of more commodious design, and longer platforms to accomodate them. The double-deck train provides seats for 1,016 passengers, compared with 772 in an ordinary eight-coach train, and 945 in ten-coach trains of new design (including coaches with central corridors). The trials have revealed that the advantage of extra seating capacity is more than outweighed by slower station working, as the double-deck train affords one door for 22 seats, compared with 10 or 12 in ordinary compartment stock. Moreover, the double-deck coaches provide less cubic capacity per passenger, and have smaller and less comforetable seats. The loading gauge restrictions make it more difficult to provide adequate ventilation in the upper deck and the dimemsions of the coaches impose severe limitations on their route availability. The experimental double-deck train was described and illustrated in our January, 1950, issue."

For an experimental train they remained in service for an impressive period of time, only being withdrawn 1st October 1971. The final service train was the 18:04 Charing Cross to Dartford via Bexleyheath. A plaque exists at Dartford Station commemorating the units.

1si October 1971. Waterloo East, the final train Charing Cross to Dartford via Bexleyheath departs. © Gerry Cork.


The withdrawn units were first stored at Plumstead and were stripped of electrical components at Slade Green. They were moved to Hoo Yard in November 1971 where all four coaches of 4001 and trailer 13504 from unit 4002 were burnt and cut up by Smeeth Metals. The remaining coaches were sold to the South Eastern Steam Centre Ashford and were moved there in March of that year.

1st December 1971, Hoo Junction. © Alan Brierly.

Preservation - The Early Years


The South Eastern Steam Centre Ashford was started by Esmond Lewis-Evans in what was the former engine shed east of Ashford station. The shed was designed by the Southern Railway and built in 1931, closing to steam in June 1962, although it was later used for diesel servicing. The Steam Centre was established in 1968, by 1974 opening once a month (Second Sunday). Sadly the centre did not get significant support to survive and closed in May 1976.

© Steve Godden.

A quote from the Kent History Forum (Sentinel S4) who had a thread on the subject back in 2011.

"I travelled in this unit when it was at Ashford. It was pulled up and down the shed side by the H class, the O1 was there looking on, it was very disappointing and I am not surprised that the site closed. It was supposed to be the Southern answer to the NRM. As for the ride, I went twice as Dad was in touch with the owner. Both times I had a ride in the coach. It was singular and both times went upstairs. I felt very closed in and it was very quiet, even with the H banging away up front. I think we will see this restored but in their own time, we may even see a complete set. But unless they can find somewhere that has the clearance then they will never run again and will only be a cosmetic restoration. I would be sad to see these fine examples of Bulleid's experimental mind vanish."

Trailer 13503 was scrapped by Car Fragmentation of Queenborough at Ashford following the closure of the Steam Centre.

© Steve Godden.

13004 - Northampton and Lamport Railway/Northampton Ironstone Railway Trust

T.W.Woods Silvertown in storage on 19th September 1984. © C.J.Marsden.
Colour photo of 13004 at Silvertown. © Peter Manley.
Following a period of storage in T.W.Woods Silvertown scrap yard 13004 was moved to the Northampton and Lamport Railway (owned by the Bulleid Double Decker Society) at Pitsford (around 1986). During its time at the NLR unsuccessful attempts were made to fit conventional buffing gear.

13004 at Pitsford and Brampton believed to be during 1986. © Philip Entwistle.

Below, left and right. 13004 Northampton and Lamport Railway, Late 1980s. © Colin Hodgin.

Above. 13004 when at the Northampton and Lamport Railway. © Glen Chippendale-Johnson.

It was later moved to the Northampton Ironstone Railway, on the 4th June 1999. The move was covered by Anglian TV.


13003 has been in storage at Sellindge in Kent since May 1999.

© Mark Green

Important Dates

September 1949 - 4001 built.

October 1949 - 4002 built.

1st November 1949 - Units go into service.

3rd November 1949 to 6th January 1950 - Out of sevice for modification.

January 1958 - BR(S) dark green livery applied.

1965 - Small Yellow warning panels.

November 1966 - 4001 at Eastleigh for repairs to 13001.

January 1968 - Full yellow ends applied.

26th September 1970 - Blue livery applied, renumbered as 4901 and 4902.

1st October 1971 - Withdrawn from service.

13th November 1971 - Moved to Hoo Yard.

22nd February 1972 - 4002 (13003-13503-13004) sold for preservation at Ashford Steam Centre.

7th March 1972 - 4002 (13003 - 13503 -13004) moved to Ashford. Class 33 via Maidstone West, Paddock Wood, Tonbridge then to Ashford.

17th July 1972 - Unit 4001 (13001-13501-13502-13002) cut up.

25th January 1973 - 13504 from unit 4002 cut up at Hoo Jct.

15th August 1984 - 13503 cut up at Ashford by Car Fragmentation of Queenborough.

? Was there September 1984 - 13004 TW Ward at Silvertown (for temporary storage).

? 1984 - 13003 Molash Farm (for temporary storage).

? 1986 - 13004 moved to Northampton and Lamport Railway.

? 1997 - 13003 moved back to Ashford.

May 1999 - 13003 moved to Hope Farm in Kent.

4th June 1999 - 13004 moved to Northampton Ironstone Railway Trust, from the Northampton and Lamport Railway.

Ian Ross
Latest Update 27th January 2018