SR Lord Nelson Class
Encyclopedia
The SR class LN or Lord Nelson class is a type of 4-cylinder 4-6-0
steam locomotive designed for the Southern Railway by Richard Maunsell
in 1926. They were intended for Continental boat trains between London (Victoria) and Dover harbour, but were also later used for express passenger work to the South-West of England. Sixteen of them were constructed, representing the most powerful (although not the most successful) Southern 4-6-0
design. They were all named after famous admirals.
The class continued to operate with British Railways until withdrawn during 1961 and 1962. Only one example of the class – the first engine, Lord Nelson itself – has been saved from scrapping. This has been seen running on mainline tours and preserved railways throughout Britain.
4-6-0 locomotives were capable of the heaviest express passenger
work between London and South-West England, there was a growth in demand for Continental traffic travelling via Dover
and Folkestone
. By the mid 1920s the Southern Railway Traffic Department wished to begin operating 500-ton express trains on these routes during peak periods. These would require a more powerful locomotive, able to pull heavier loads at sustained speeds of 55 mph (24.6 m/s), so as not to impede the congested electrified lines around London. However, any enlargement of the existing 2-cylinder design was not possible due to weight restrictions imposed by the railway’s Civil Engineer
.
After examining the practice of other British railways, Richard Maunsell, the Chief Mechanical Engineer
, secured agreement for a 4-cylinder design, with an improved boiler
and Belpaire firebox
. The drive would be divided
between the front coupled axle for the inside cylinders and the middle coupled axle for the outside cylinders giving better weight distribution and reduced hammer blow
. The new design was an inevitable compromise between the need for additional power and to keep the weight down to an acceptable limit.
There were two unusual features of the design: the first of which was the setting of the crank axles at 135°, rather than the standard 90° of other locomotive types. This gave eight beats per revolution, rather than the usual four, designed to give a more even draw on the fire. The second difference was that fire grate was in two sections, the rear portion was horizontal and the front sloped away sharply.
depot. A further batch of ten locomotives was ordered in 1928, before the previous batch had been delivered, but when it became apparent that the Stock Market Crash
of October 1929 would be likely to reduce the demand for Continental travel, this second order was reduced to five.
admiral
s, with the doyen of the class being named Lord Nelson. As a result the rest of the locomotives belonged to the Lord Nelson (LN) class.
during the late 1920s.
Maunsell was aware of the reputation for poor steaming enjoyed by the class and attempted to address it by the fitting of twin Kylchap
blastpipe
s to No. 860 in 1934.. However, the problem was ultimately solved by Oliver Bulleid
, Maunsell's replacement as Chief Mechanical Engineer of the Southern in 1938. He fitted larger diameter chimneys and Lemaître
multiple jet blastpipe
s, which effectively transformed their performance. Thereafter the class was highly respected.
For a period after its introduction to the Southern Railway network, the Lord Nelson class held the title of "most powerful locomotive in Britain" – a claim based on its tractive effort
. The advanced design of the locomotive led to the GWR
introducing the GWR 6000 Class
in order to regain the title lost by their GWR Castle class locomotives when the Lord Nelsons were constructed. The planned 500-ton trains never materialised, but the class was regularly used on 460 ton trains such as the Golden Arrow. After the Second World War they were also frequently used on heavily laden Boat Trains between London Waterloo station and Southhampton docks
.
The Lord Nelsons were notoriously difficult for inexperienced crews to fire properly, due to their long firebox, and specific crews who had proven experience in firing the locomotives were therefore allocated to them. The was due to the relatively few locomotives in the class for crews to train on. The LMS Royal Scot Class
was loosely based on this design.
failure due to lack of water 23 April 1945, killing the fireman and injuring the driver. No. 851 was involved in a serious derailment at Byfleet
in December 1946, due to the poor condition of the permanent way
.
, although throughout the 1950s they were frequently called upon during peak periods or to deputise for failures. The rebuilding of the Pacifics in the late 1950s and their subsequent increased reliability rendered the Lord Nelson surplus to operational requirements, and they were gradually phased out of service. The entire class was withdrawn during 1961 and 1962.
The only survivor, first-of-class (30)850 Lord Nelson, has been preserved as part of the National Collection
, and has run on the national rail network. As of 2009–10 it was based on the Mid-Hants Railway.
Numbers allocated to the locomotives were a variation of LSWR practice and, being constructed at Eastleigh, were given the prefix "E" before the number to distinguish from the locomotives of other pre-grouping railway companies that also carried the same number. In the case of the Lord Nelson class the numbering ranged from E850 to E865. This was eventually superseded by numbers without the "E" prefix, becoming 850 to 865 from 1931.
4-6-0
Under the Whyte notation for the classification of steam locomotives, 4-6-0 represents the wheel arrangement of four leading wheels on two axles in a leading truck, six powered and coupled driving wheels on three axles, and no trailing wheels. This wheel arrangement became the second-most popular...
steam locomotive designed for the Southern Railway by Richard Maunsell
Richard Maunsell
Richard Edward Lloyd Maunsell held the post of Chief Mechanical Engineer of the South Eastern and Chatham Railway from 1913 until the 1923 Grouping and then the post of CME of the Southern Railway in England until 1937....
in 1926. They were intended for Continental boat trains between London (Victoria) and Dover harbour, but were also later used for express passenger work to the South-West of England. Sixteen of them were constructed, representing the most powerful (although not the most successful) Southern 4-6-0
4-6-0
Under the Whyte notation for the classification of steam locomotives, 4-6-0 represents the wheel arrangement of four leading wheels on two axles in a leading truck, six powered and coupled driving wheels on three axles, and no trailing wheels. This wheel arrangement became the second-most popular...
design. They were all named after famous admirals.
The class continued to operate with British Railways until withdrawn during 1961 and 1962. Only one example of the class – the first engine, Lord Nelson itself – has been saved from scrapping. This has been seen running on mainline tours and preserved railways throughout Britain.
Background
Although the improved ”King Arthur” classLSWR N15 Class
The LSWR N15 class was a British 2–cylinder 4-6-0 express passenger steam locomotive designed by Robert W. Urie. The class has a complex build history spanning three sub-classes and eight years of construction from 1919 to 1926...
4-6-0 locomotives were capable of the heaviest express passenger
Passenger
A passenger is a term broadly used to describe any person who travels in a vehicle, but bears little or no responsibility for the tasks required for that vehicle to arrive at its destination....
work between London and South-West England, there was a growth in demand for Continental traffic travelling via Dover
Dover
Dover is a town and major ferry port in the home county of Kent, in South East England. It faces France across the narrowest part of the English Channel, and lies south-east of Canterbury; east of Kent's administrative capital Maidstone; and north-east along the coastline from Dungeness and Hastings...
and Folkestone
Folkestone
Folkestone is the principal town in the Shepway District of Kent, England. Its original site was in a valley in the sea cliffs and it developed through fishing and its closeness to the Continent as a landing place and trading port. The coming of the railways, the building of a ferry port, and its...
. By the mid 1920s the Southern Railway Traffic Department wished to begin operating 500-ton express trains on these routes during peak periods. These would require a more powerful locomotive, able to pull heavier loads at sustained speeds of 55 mph (24.6 m/s), so as not to impede the congested electrified lines around London. However, any enlargement of the existing 2-cylinder design was not possible due to weight restrictions imposed by the railway’s Civil Engineer
Civil engineer
A civil engineer is a person who practices civil engineering; the application of planning, designing, constructing, maintaining, and operating infrastructures while protecting the public and environmental health, as well as improving existing infrastructures that have been neglected.Originally, a...
.
After examining the practice of other British railways, Richard Maunsell, the Chief Mechanical Engineer
Chief Mechanical Engineer
Chief Mechanical Engineer and Locomotive Superintendent are titles applied by British, Australian, and New Zealand railway companies to the person ultimately responsible to the board of the company for the building and maintaining of the locomotives and rolling stock...
, secured agreement for a 4-cylinder design, with an improved boiler
Boiler
A boiler is a closed vessel in which water or other fluid is heated. The heated or vaporized fluid exits the boiler for use in various processes or heating applications.-Materials:...
and Belpaire firebox
Belpaire firebox
The Belpaire firebox is a type of firebox used on steam locomotives. It was invented by Alfred Belpaire of Belgium. It has a greater surface area at the top of the firebox, improving heat transfer and steam production...
. The drive would be divided
Divided drive (locomotive)
A divided drive locomotive is a steam locomotive that divides the driving force on its wheels by using different cylinders to power different pairs of driving wheels in order to give better weight distribution and reduce "hammer blow" which can be damaging to the track, or else to enable the wider...
between the front coupled axle for the inside cylinders and the middle coupled axle for the outside cylinders giving better weight distribution and reduced hammer blow
Hammer blow
Hammer blow, in rail terminology, refers to the vertical forces transferred to the track by the driving wheels of a steam locomotive and some diesel locomotives. The largest proportion of this is due to the unbalanced reciprocating motion, although the piston thrusts also contribute a portion to it...
. The new design was an inevitable compromise between the need for additional power and to keep the weight down to an acceptable limit.
There were two unusual features of the design: the first of which was the setting of the crank axles at 135°, rather than the standard 90° of other locomotive types. This gave eight beats per revolution, rather than the usual four, designed to give a more even draw on the fire. The second difference was that fire grate was in two sections, the rear portion was horizontal and the front sloped away sharply.
Construction history
The prototype E850 named Lord Nelson was ordered from Eastleigh railway works in June 1925 but production proceeded slowly, at Maunsell’s insistence, to ensure that the weight was kept to a minimum at every stage, so the locomotive did not appear until August 1926. It was tested on a variety of duties over the next year, with sufficiently encouraging results for an initial order for ten more locomotives for delivery between May 1928 and April 1929 to be placed. These were originally scheduled to be allocated to Battersea depot and fitted with 4,000 gallon 6-wheeled tenders suitable for the Continental ports. However, during construction, it was decided to equip half of the class with 5,000 gallon 8-wheeled tenders necessary for the longer West of England routes and to allocate them to Nine ElmsNine Elms
Nine Elms is a suburb of London, situated in the far north-eastern corner of the London Borough of Wandsworth between Battersea and Vauxhall.It is primarily an industrial area, dominated by Battersea Power Station, Battersea Dogs and Cats Home, railway lines, a major Royal Mail sorting office and...
depot. A further batch of ten locomotives was ordered in 1928, before the previous batch had been delivered, but when it became apparent that the Stock Market Crash
Stock market crash
A stock market crash is a sudden dramatic decline of stock prices across a significant cross-section of a stock market, resulting in a significant loss of paper wealth. Crashes are driven by panic as much as by underlying economic factors...
of October 1929 would be likely to reduce the demand for Continental travel, this second order was reduced to five.
Naming the locomotives
The locomotives were all named after famous Royal NavyRoyal Navy
The Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...
admiral
Admiral
Admiral is the rank, or part of the name of the ranks, of the highest naval officers. It is usually considered a full admiral and above vice admiral and below admiral of the fleet . It is usually abbreviated to "Adm" or "ADM"...
s, with the doyen of the class being named Lord Nelson. As a result the rest of the locomotives belonged to the Lord Nelson (LN) class.
Modifications
The performance of the new locomotives was mixed, depending upon the experience of the crew and the circumstances under which they were operating. At times it was no better than their smaller predecessors. Maunsell therefore undertook a number of experiments to try to improve the performance of the new locomotives. No. E859 was fitted with smaller 6ft 3in (1.9m) driving wheels to see if this would improve performance over the heavily graded London-Dover line, but the difference was marginal. No. E860 was fitted with a longer, heavier boiler but once again with little improvement. The whole class however benefitted from the fitting of smoke deflectorsSmoke deflectors
Smoke deflectors are vertical plates attached to the front of a steam locomotive on each side of the smokebox. They are designed to lift smoke away from the locomotive at speed so that the driver has better visibility unimpaired by drifting smoke....
during the late 1920s.
Maunsell was aware of the reputation for poor steaming enjoyed by the class and attempted to address it by the fitting of twin Kylchap
Kylchap
The Kylchap steam locomotive steam locomotive exhaust system was designed and patented by the famous French steam engineer André Chapelon, using a second-stage nozzle designed by the Finnish engineer Kyösti Kylälä and known as the Kylälä spreader; thus the name KylChap for this design.The Kylchap...
blastpipe
Blastpipe
The blastpipe is part of the exhaust system of a steam locomotive that discharges exhaust steam from the cylinders into the smokebox beneath the chimney in order to increase the draught through the fire.- History :...
s to No. 860 in 1934.. However, the problem was ultimately solved by Oliver Bulleid
Oliver Bulleid
Oliver Vaughan Snell Bulleid was a British railway and mechanical engineer best known as the Chief Mechanical Engineer of the Southern Railway between 1937 and the 1948 nationalisation, developing many well-known locomotives.- Early life and Great Northern Railway :He was born in Invercargill,...
, Maunsell's replacement as Chief Mechanical Engineer of the Southern in 1938. He fitted larger diameter chimneys and Lemaître
Jean Lemaître
Jean Lemaître was a mechanical engineer from the Nord Belge Railway, who developed a Steam locomotive exhaust system.The Lemaître Exhaust featured 5 nozzles in a circular pattern exhausting up a large-diameter stack, with a variable area nozzle exhausting up the center, and improved efficiency by...
multiple jet blastpipe
Blastpipe
The blastpipe is part of the exhaust system of a steam locomotive that discharges exhaust steam from the cylinders into the smokebox beneath the chimney in order to increase the draught through the fire.- History :...
s, which effectively transformed their performance. Thereafter the class was highly respected.
Operational details
- For location details and current status of the preserved locomotive, see: List of Lord Nelson class locomotives
For a period after its introduction to the Southern Railway network, the Lord Nelson class held the title of "most powerful locomotive in Britain" – a claim based on its tractive effort
Tractive effort
As used in mechanical engineering, the term tractive force is the pulling or pushing force exerted by a vehicle on another vehicle or object. The term tractive effort is synonymous with tractive force, and is often used in railway engineering to describe the pulling or pushing capability of a...
. The advanced design of the locomotive led to the GWR
Great Western Railway
The Great Western Railway was a British railway company that linked London with the south-west and west of England and most of Wales. It was founded in 1833, received its enabling Act of Parliament in 1835 and ran its first trains in 1838...
introducing the GWR 6000 Class
GWR 6000 Class
The Great Western Railway 6000 Class or King is a class of 4-6-0 steam locomotive designed for express passenger work. With the exception of one Pacific , they were the largest locomotives the GWR built. They were named after kings of the United Kingdom and of England, beginning with the reigning...
in order to regain the title lost by their GWR Castle class locomotives when the Lord Nelsons were constructed. The planned 500-ton trains never materialised, but the class was regularly used on 460 ton trains such as the Golden Arrow. After the Second World War they were also frequently used on heavily laden Boat Trains between London Waterloo station and Southhampton docks
Southampton Terminus railway station
Southampton Terminus railway station served the docks and city centre of Southampton, England. The station was first authorized on the 25 July 1834, it began as the terminus of the London and South Western Railway...
.
The Lord Nelsons were notoriously difficult for inexperienced crews to fire properly, due to their long firebox, and specific crews who had proven experience in firing the locomotives were therefore allocated to them. The was due to the relatively few locomotives in the class for crews to train on. The LMS Royal Scot Class
LMS Royal Scot Class
The London, Midland and Scottish Railway Royal Scot Class is a class of 4-6-0 express passenger locomotive introduced in 1927. Originally having parallel boilers, all members were later rebuilt with tapered type 2A boilers, and were in effect two classes.-Background:Until the mid-1920s, the LMS...
was loosely based on this design.
Accidents and incidents
One member of the Lord Nelson class was involved in what could have been a major accident on 23 January 1930. This entailed the leading driving wheels jumping off the track, though the locomotive ran for many yards before they re-railed themselves over a point. No. 852 received a direct hit from an enemy bomb on 18 April 1941, and was so severely damaged that it was not returned to service until June 1942.. No. 854 suffered a fireboxFirebox
In a steam engine, the firebox is the area where the fuel is burned, producing heat to boil the water in the boiler. Most are somewhat box-shaped, hence the name.-Railway locomotive firebox :...
failure due to lack of water 23 April 1945, killing the fireman and injuring the driver. No. 851 was involved in a serious derailment at Byfleet
Byfleet
Byfleet is an inland island village forming a suburb of Woking in Surrey, England. It is in the east of the borough between the River Wey and the River Mole, and is within the M25 motorway....
in December 1946, due to the poor condition of the permanent way
Permanent way
The permanent way is the elements of railway lines: generally the pairs of rails typically laid on the sleepers embedded in ballast, intended to carry the ordinary trains of a railway...
.
Withdrawal and preservation
The class was gradually superseded on top link expresses during the 1940s by growing numbers of Bulleid PacificsBulleid pacific
Bulleid pacific may refer to the following classes of British steam railway locomotives:* SR Merchant Navy Class* SR West Country and Battle of Britain Classes...
, although throughout the 1950s they were frequently called upon during peak periods or to deputise for failures. The rebuilding of the Pacifics in the late 1950s and their subsequent increased reliability rendered the Lord Nelson surplus to operational requirements, and they were gradually phased out of service. The entire class was withdrawn during 1961 and 1962.
The only survivor, first-of-class (30)850 Lord Nelson, has been preserved as part of the National Collection
National Railway Museum
The National Railway Museum is a museum in York forming part of the British National Museum of Science and Industry and telling the story of rail transport in Britain and its impact on society. It has won many awards, including the European Museum of the Year Award in 2001...
, and has run on the national rail network. As of 2009–10 it was based on the Mid-Hants Railway.
Southern Railway
The Lord Nelson class was initially painted in Maunsell lined olive green, which later changed to a lighter shade in the mid-1930s. From 1938, some of the locomotives were painted in a semi-matt Malachite Green finish when Bulleid replaced Maunsell as CME of the Southern. During the war years, the locomotives were painted in wartime black livery, though retained the word "Southern" in yellow on the tender. After the war, the livery was reverted to the Southern Railway Malachite Green standard with "Sunshine Yellow" lining on the boiler rings.Numbers allocated to the locomotives were a variation of LSWR practice and, being constructed at Eastleigh, were given the prefix "E" before the number to distinguish from the locomotives of other pre-grouping railway companies that also carried the same number. In the case of the Lord Nelson class the numbering ranged from E850 to E865. This was eventually superseded by numbers without the "E" prefix, becoming 850 to 865 from 1931.