BB & WC 4-6-2 SR Bulleid Battle of Britain & West Country 34001 – 34110

Bb & WC.jpg


Power Classification 6MT reclassified 7P5F in 1953

Rebuilt locomotives reclassified 7P6F in 1961

Introduced 1945 – 1951
Designer Bulleid
Company SR
Weight – Loco 86t 0cwt – Rebuilt locomotives 90t 1cwt
               Tender 4,500 gallon – 42t 12cwt

5,500 gallon – 47t 5cwt

Driving Wheels 6ft 2ins
Boiler Pressure 280psi superheated – Later reduced to 250psi
Cylinders Three – 16⅜in x 24in
Tractive Effort 31,050lbf  – Later reduced to 27,715lbf
Valve Gear Bullied (piston valve)

Rebuilt locomotives Walschaert (piston valves)

The SR West Country and Battle of Britain classes, collectively known as Light Pacifics or informally as Spam Cans, are air-smoothed 4-6-2 Pacific steam locomotives designed for the Southern Railway by its Chief Mechanical Engineer Bulleid. Incorporating a number of new developments in British steam locomotive technology, they were amongst the first British designs to use welding in the construction process, and to use steel fireboxes, which meant that components could be more easily constructed under wartime austerity and post-war economy.

The Merchant Navy Pacifics were restricted in their route availability. The West Country and Battle of Britain classes were designed as a lighter version with wider route availability to permit use on a wider variety of routes, including in the south-west of England and the Kent coast. They had an axle-loading of 18 tons 15 cwt a were known as light pacifics.

They were a mixed-traffic design, being equally adept at hauling passenger and freight trains, and were used on all types of services, frequently far below their capabilities. A total of 110 locomotives were constructed between 1945 and 1950.

The engines carried Bullied’s continental type numbers and were numbered from 21C101 (The first three indicate the wheel arrangement thus 2 leading axles, 1 trailing axle, and six (C) driving wheels (4-6-2).  The last three digits indicate the series 1(00) light Pacifics of with the last two relating to the order in which they are built and numbered).

His scheme was abolished by British Railways, which renumbered existing locomotives 34001-34070 and new locomotives 34071-34110.

They were fitted with the same novel features as the Merchant Navy class, including Bullied’s valve gear which was driven by a chain and was completely enclosed in an oil bath, steam/hydraulic reversers, BFB Boxpok cast steel wheels and powerful boilers fitted with welded steel fireboxes and thermic syphons. As on the MN class the boiler pressure was originally 280psi but it was later reduced to 250psi to reduce maintenance costs. The smokebox housed the five-nozzle Lemaître blastpipe arranged in a circle within a large-diameter chimney and the locomotives were covered in an air casing.

As with the Merchant Navy class, electric lighting was provided on both locomotive and footplate, powered by a steam-powered generator below the footplate. The gauges were lit by ultra-violet light. This enabled clearer night-time vision of the boiler steam pressure gauge and the brake pipe vacuum pressure gauge whilst eliminating dazzle, making it easier for the crew to see signals along the track. Close attention was paid to the ergonomics of the cab, which was designed with the controls required for operation grouped according to the needs of both driver and fireman, thus promoting safe operation. As an aid to the fireman, a treadle used steam pressure to open the firebox doors. The footplate was entirely enclosed, improving crew working conditions in winter.

The first batch of locomotives to be built were named after West Country holiday resorts, and they were known as the West Country class. Due to wartime contract work at Brighton Works, the boilers were built under contract at the North British Locomotive Company. Before the first of the class had been delivered, the order was increased to thirty, with a second batch of ten ordered in 1944. Deliveries from Brighton Works began in 1945 with prototype 21C101 Exeter, and proceeded at the rate of about two locomotives per month. The class was gradually run in on the Central Section until October 1945, when they were successfully trialled on Plymouth and Kentish services. By the time the first fifteen had entered traffic a further order of fifteen was placed, with these entering service in 1946. From this batch onwards, traction was improved by the addition of steam sanding to the front driving wheel, with covers added to protect the motion from sand falling from the filler pipes.

The later engines built from 1946 onwards were intended for service on the Eastern Section. They carried names with wartime connections, mainly being named after RAF Squadrons which played such a key part in the Battle of Britain. They were therefore known as the battle of Britain class although they were identical with the West Country class.

By the time of the nationalisation of British Railways in January 1948, seventy Light Pacifics had been built at Brighton Works, with a fourth batch of twenty on order. There was a delay in production during the first three months of British Railways control but the last twenty ordered by the Southern Railway entered traffic between April 1948 and February 1949.

In March 1949, British Railways ordered a final 20 from Brighton works despite a pressing need for smaller tank locomotives. This imbalance was rectified by building forty-one examples of the LMS Fairburn 2-6-4T for the Southern Region. Also at this time Brighton Works staff were embroiled in the difficulties associated with Bulleid’s experimental and problematic Leader class. As a result, Brighton sought assistance from the other Southern Region works to complete this final order. Ashford works cut the frames and constructed the tenders, and Eastleigh works constructed six of the final batch of locomotives.

The completion of the final locomotive, 34110 66 Squadron, in January 1951 was delayed for several months pending consideration of proposals from British Railways management for a major modification to a standard two-cylinder design without the chain-driven valve gear, but the locomotive entered service as Bulleid intended.

The first six locomotives were initially fitted with plywood sheeting over the cab-side windows as a wartime material-saving measure, with 21C107 Wadebridge the first to receive glass windows. Two of the front route indicator irons (of which there are five) were originally located on the smoke deflectors, which meant that the indicator discs stood proud of the casing. This necessitated a trial relocation to the smokebox door at the three and nine o’clock positions on 21C109 Lyme Regis, and fitted as standard from 21C118 Axminster onwards. The batch constructed between June and October 1946 received a modified steam regulator and LMS-style parallel buffer casings.

Like the Merchant Navy class, they were fitted with a new design of cab front spectacle plates from mid–1947 due to poor forward visibility. The small windows on the front face of the cab were redesigned to an angled profile, giving improved visibility to the driver. This was a feature fitted to all Bulleid-designed locomotives post-nationalisation. Over the next decade the revised design was fitted to existing members of the class. Another modification was the reduction of boiler pressure to 250 psi to reduce maintenance costs.

The Southern Railway-built batches had a narrow 8ft 6in footplate due to the width-restricted Hastings Line between Tonbridge and Hastings but these were never used on this duty and the cab was widened to 9ft on the British Railways batch. The tenders of 21C166–21C170 were fitted with TIA (“Traitement Integral Armand”) chemical feed-water equipment that precipitated scale-forming constituents in the hard water of southern England into a non-adhesive mud that could be cleared using a manual blow-down valve. This equipment was retrospectively fitted to earlier members of the class. In 1948 the tender design was enlarged to provide a water capacity of 5,500-imperial-gallon.

To ease maintenance and lubrication, panels of air-smoothed casing ahead of the cylinders were removed from 1952, and the front sanders were blanked off. This coincided with the removal of the tender raves on all but five locomotives, as they obstructed the packing of coal into the bunker and restricted the driver’s view when reversing. The resultant cut-down tender included new, enclosed storage for fire-irons and glass spectacle plates to protect the crew from flying coal dust when running tender-first.

As with the Merchant Navy class, they could generate great power using mediocre quality fuel, due largely to Bulleid’s excellent boiler. They also ran smoothly at high speed, but they were also beset with the same technical problems of the MN class. These may be summarised as follows:

  • Adhesion problems. The lighter loading on their driving axles meant that they were even more prone to wheelslip than the Merchant Navy class, requiring very careful control when starting a heavy train. Once underway they were noted for their free running, excellent steam production and rapid turn of speed.
  • Maintenance problems. The chain-driven valve gear proved to be expensive to maintain and subject to rapid wear. Leaks from the oil bath onto the wheels caused oil to splash onto the boiler lagging. Once saturated with oil, the lagging attracted coal dust and ash, which provided combustible material, and sparks from heavy braking would set the lagging on fire underneath the air-smoothed casing. The fires were also attributed to oil overflowing from axlebox lubricators onto the wheels when stationary, to be flung upwards into the boiler lagging in service. In either case, the local fire brigade would be called to put the fire out, with cold water coming into contact with the hot boiler causing stress to the casings.
  • High fuel consumption. This was highlighted during the 1948 locomotive exchanges undertaken by British Railways, and very apparent at Exmouth Junction shed where the Light Pacifics burned 47.9lb of coal per mile compared to 32lb for the T9 class that they replaced.
  • Restricted driver visibility due to the air-smoothed casing and soft steam exhaust from the multiple-jet blastpipe. The exhaust problem was never adequately resolved, and smoke continued to beat down onto the casing while moving, obscuring the driver’s vision. There was much experimentation in order to resolve this problem, with varying degrees of success.

Due to the problems experienced with the class, and following the success of the rebuilt Merchant Navy class designed by Jarvis, British Railways ordered the rebuilding of sixty locomotives to a more conventional design at Eastleigh between 1957 and 1961. This was done on the basis that the locomotives would be in service until 1987 which proved to be a false justification.

The first locomotive to be rebuilt was 34005 Barnstaple, which adopted many features from the BR Standard locomotive classes. The casing was removed and replaced with conventional boiler cladding, boiler pressure reduced to 250 psi and the chain-driven valve gear was replaced with modified Walschaerts valve gear fitted between the frames.

The rapid onset of the 1955 Modernisation Plan during the early 1960s meant that the remaining fifty locomotives were not rebuilt, and continued in as-built condition until withdrawal.

The rebuilding solved most of the maintenance problems whilst retaining the excellent features of the original design. Repair costs were reduced by up to 60%, and coal consumption was reduced by up to 8.4%. However the Walschaerts valve gear made the rebuilds heavier and prone to hammerblow on the track, a complaint that was not evident with the original design. The increased weight reduced their route availability, meaning that they could not be used on certain routes available to un-rebuilt examples, such as the line to Ilfracombe.

34064 was fitted with a Giesl ejector chimney in 1962 on the grounds that a desired spark arrestor would suffocate an ordinary blastpipe. Following some adjustment, the ejector improved smoke deflection and fuel consumption, allowing it to steam well with low-grade coal. As a consequence of the positive experience with 34064, preserved 34092 City of Wells was similarly fitted in the mid-1980s.

34019 and 34036 were converted to oil burning in 1947 but were later reconverted to coal burning.

The original intention was to base the first batch of locomotives at Exmouth Junction depot at Exeter for use on the West of England Main Line to Salisbury and Plymouth, and secondary lines to Barnstaple, Bude and other holiday resorts in Devon and Cornwall. By the winter of 1945, there was a more pressing need for them on Kent Coast services. The class also began to be used on Continental Boat Trains to and from Dover and Folkestone once these were resumed in 1946. Later batches were used on cross-country services such as the Brighton to Bournemouth, Cardiff and Plymouth trains or the Somerset and Dorset Joint Railway trains from Bournemouth to Wells and Bath.

Because of the good route availability the locomotives could be used on non-electrified lines between London and Brighton. These included the Oxted Line, and occasionally the Bluebell Line between East Grinstead and Lewes, where they were also used for freight and parcels traffic, and excursion trains over electrified lines. Thus the original intention for the West Country class locomotives to work in South West England and the Battle of Britain class in Kent, Hampshire, Sussex and Surrey was never operationally practical and both classes were to be found all over the network.

The electrification of the Chatham Main Line to Dover and Ramsgate in 1959 deprived the class of some of its work, as did the transfer of the lines west of Salisbury to the Western Region in 1962. This resulted in the withdrawal of several unrebuilt locomotives stabled at Exmouth Junction shed in June 1963. By the end of the year ten had been withdrawn, including the 12‑year-old 34110 66 Squadron, having travelled only 600,000 miles. Most of the unrebuilt locomotives were withdrawn over the next three years but seven survived until 1967 and the end of steam on the Southern Region. Many rebuilt locomotives were withdrawn soon after their rebuilding. The first was 34028 Eddystone in 1964, having run only 287,000 miles since rebuilding. Other early withdrawals included 34109 Sir Trafford Leigh-Mallory which had only travelled 162,000 miles in the three and a half years since its rebuilding.

Number in Service.

Built Rebuilt Withdrawals No. in Service
BR Numbers Quantity As Built


1945 34001-20



1946 34021-52



1947 34053-70



1948 34071-89



1949 34090-100



1950 34101-9



1951 34110











      86     24





   59     51







40     60












  • 34001-94, 34096, 34098, 34100, 34103 and 34105-10 were built at Brighton.
  • 34095, 34097, 34099, 34101-2 and 34104 were built at Eastleigh

Allocation of locomotives in service as at 1st of January.


1948 1960






Bricklayers Arms




Dover Marine





Exmouth junction



Nine Elms










Stewarts Lane






  • Ramsgate shed was closed June 1959
  • Bournemouth and Stewarts Lane sheds were closed September 1963
  • Exmouth Junction was transferred to Western Region control in September 1963

Accidents and Incidents

  • On 4 December 1957 34066 Spitfire crashed into the back of a stationary local train at St John’s station in Lewisham resulting in the death of 90 people and 173 people injured.
    • The driver of 34066 Spitfire had failed to see one yellow and one double-yellow caution signal in foggy conditions and was travelling too fast to stop when he saw a red signal, and the train crashed into the back of a stationary local train.
    • The report on the disaster indicated that with the signals concerned being on the right hand side of the train, it was necessary, because of the limited visibility from the left hand side of a steam locomotive, for either the fireman to observe those signals (but with the driver being responsible for asking him to do so) or for the driver to cross over the footplate from his left hand driving position to observe them from the other side. In the event neither happened and neither looked out for the aspect of the signals.
    • The report ascribed blame to the driver, but recommended that the class be fitted with wider windscreens to improve visibility, noting that in fog with less than 80 yards’ visibility the three signals involved would not be visible at all from the driver’s side of the footplate; however, it noted that even from a Schools class locomotive with its much smaller boiler, it would be unlikely that these signals could be seen from the driver’s side in the dense foggy conditions of the incident. The report did not suggest that poor lifting of smoke obstructed visibility.
    • Members of the class were later fitted with Automatic Warning System equipment, a recommendation of the incident report; fitting of trackside equipment was already underway, but with priority given to routes equipped with semaphore signals, not electric colour-light signals as at Lewisham.
  • On 30 October 1959, 34020 Seaton was hauling a passenger train that overran signals and was derailed by trap points at St Denys, Hampshire.
  • On 20 February 1960, 34084 253 Squadron was hauling a freight when is overran signals at Hither Green and was derailed, falling down an embankments and onto its side. The locomotive and tender were subsequently recovered.
  • On 12 December 1960, 34022 Exmoor was hauling a passenger train that overran signals and was derailed by trap points at St Denys. Two people were injured.
  • On 11 April 1961, 34040 Crewkerne was in a head-on collision with an electric multiple unit at Waterloo station, after the latter overran signals. One person was killed and fourteen were injured.
  • On 2 September 1961, 34045 Ottery St Mary was derailed by trap points at Bournemouth Central, Hampshire.
  • When 34053 Sir Keith Park was being towed to Woodham Brothers scrapyard in Barry after withdrawal from service in October 1965 one of the connecting rods which were being transported in the tender of 34053 struck a bridge near Chandlers Ford.
  • On 31st December 2007 some flamable material was left on the footplate of 34007 Wadebridge overnight, with the engine in light steam, leading to the unfortunate events when the material caught light, causing a fire that destroyed the cab.
  • On 7th March 2015, 34067 Tangmere was hauling a Cathedrals Express charter train operated by West Coast Railways (Bristol Temple Meads to Southend Victoria) that overran a signal at Wooton Bassett, Wiltshire by 700 yards. The incident occurred around one minute after the up/east bound First Great Western service from Swansea to London Paddington approaching via the South Wales Main Line from Badminton, Gloucestershire and operated by an InterCity 125 set, had cleared the junction at 100 miles per hour.
  • On 26th February 2016 a volunteer on the West Somerset Railway was injured after being crushed between the 34053 Sir Keith Park and its tender, while the locomotive was being unloaded from its road trailer at Bishops Lydeard. The injured person subsequently recovered.


Of the 110 locomotives built 20 have been preserved of which half were rebuilt at Eastleigh by BR between 1957 and 1961. Only two (34023 Blackmore Vale and 34051 Winston Churchill) were not sent to Woodham Brother for scrap. 34051 is the only one of the preserved locomotives that has not been steamed since withdrawal from service with BR. 


Miles Since Rebuilt

Miles In service

34007  Wadebridge


34010  Sidmouth



34016  Bodmin



34023  Blackmore Vale


34027  Taw Valley



34028  Eddystone



34039  Boscastle



34046  Braunton



34051  Winston Churchill


34053  Sir Keith Park



34058  Sir Fredrick Pile



34059  Sir Archibald Sinclair



34067  Tangmere


34070  Manston


34072  257 Squadron


34073  249 Squadron


34081  92 Squadron


34092  City of Wells


34101  Hartland



34105  Swanage


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