| LNER Thompson Class A1/1 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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 The single Thompson A1/1 Pacific 60113 Great Northern near Peterborough in 1959 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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The LNER Class A1/1 consisted of a single 4-6-2 "Pacific" express passenger locomotive rebuilt in 1945 from an A1 class locomotive, by Edward Thompson. It was intended as the prototype of a new design of pacific locomotives improving the A4 design of Thompson's predecessor Sir Nigel Gresley. No further examples were built due to Thompson's retirement in 1946.
When Edward Thompson was appointed Chief Mechanical Engineer of the London and North Eastern Railway in April 1941, he envisaged a new standardisation programme involving ten locomotive designs including two Pacific types. [1] These were an express passenger type (designated A1) with 6 ft 8 in (2.032 m) driving wheels and a ‘heavy passenger and freight’ type (designated A2) with 6 ft 2 in (1.880 m) driving wheels. He was not able to proceed with his plan due to the Second World War but did try out some of his ideas by rebuilding Nigel Gresley’s P2 class 2-8-2 as A2/2 pacifics and building the last four V2 class already on order as A2/1 pacifics. At last in July 1944 Thompson began work on designing his new A1 class incorporating everything learned from the twenty-plus years of Gresley's development of the 6 ft 8 in (2.032 m) Pacific locomotives along with the construction and operation of the rebuilt P2 and A2/1. Thompson had no desire to rebuild the Gresley A10 and A3 classes to the new specification as he believed they were an essential part of the LNER locomotive fleet, with Simon A.C. Martin suggesting that O.S. Nock's pamphlet produced for the LNER may have suggested so. [2] Some commentators believed that he intended to rebuild one of the surviving Gresley pacifics of the A1 class to try out the new design. [3]
Thompson's A1/1 design differed from his previous designs by adopting a divided drive with the centre cylinder, where the inside connecting rod was of a different length to the outside one, ignoring the presumed advantages provided by an equal length connecting rods and the subsequent valve events. [4] This gave an elongated look with the resulting wheelbase being 38 ft 5 in (11.709 m) long, even longer than the Gresley P2s.
The final design omitted the inside Gresley conjugated valve gear in favour of three independent sets of Walschaerts valve gear. Steam was generated using a diagram No. 107 boiler, which was used on Gresley A4 locomotives, necessitating the use of A4 frames. [5] The smokebox was carefully developed based on the practice set by the rebuilt P2 locomotives. [5] Thompson followed Gresley's development with a double Kylchap chimney and his draughting arrangement. [6] There was also a reversion to flat fronted cabs and cab floor out of safety concerns, [7] similar in style to Gresley A3 and in dimension to his B1 locomotives. Electric lighting and hinged discs were fitted to the front of the locomotive. [4]
No. 4470 Great Northern, the very first Gresley Pacific, was chosen for this rebuilding rather than being retained for future preservation. There has been much debate on the reason for this choice. Some has blamed Thompson for letting his personal feelings towards Gresley cloud his judgement. O. S. Nock describes it as ‘the most disappointing and tactless act in his short and stormy career as CME,’ [1] and C. J. Allen stated ‘he turned it into a machine of such hideous appearance as might well have made its designer turn in his grave.’ [8]
Simon A.C. Martin believes that Thompson lacked tact and has misread the attachment of the railwaymen to Great Northern and the selection of the locomotive was not his decision, but that of the Locomotive Running Superintendent. [9] Such a decision would have been based on the proposed locomotive's age, total mileage to date, mileage since last shopping and overall condition. [9] The late Richard Hardy, a draughtsman working on Great Northern stated that had the Chief Draughtsman Teddy Windle remonstrated with Thompson, Thompson would have replied that it was not his decision. [10] [11] As the first Gresley Pacific, Great Northern has been in service since 1922 and was being shopped at the time of the selection, hence its selection.
The A1 prototype was classed both as an express passenger locomotive and as a rebuild of an existing locomotive out of expediency due to wartime austerity measures. [6] However, very limited amount of the original locomotive were retained in the rebuilding, such as the driving wheels, parts of the rear cartazzi, the tender frames and wheels. [6] The boiler and original frame of the Gresley A10 were put into the spares pool with the frames refurbished and reused on another locomotive. [6]
The rebuilt locomotive appeared in traffic in September 1945 in Great Eastern Railway Prussian Blue with double red lining with "NE" on the tender, likely in direct tribute to three of four major railways that made up the LNER, however no written reasoning, instruction or notice were given. [12] The locomotive was classified A1 while the remaining sixteen locomotives of Gresley's A1 class were re-classified A10.
There were also plans for streamlining all the members of the new A1 class, but these were never acted upon, [3] with a logical scenario being due to wartime austerity measures making the additional material requirement of streamlining unacceptable to the LNER Emergency Board. [4]
In October 1945, the order was given to construct sixteen new locomotives to the new A1 plan. However, before these could be built Thompson had retired and Arthur Peppercorn had taken over as CME and he deferred building them until 1948, by which time he had altered the design to become the Peppercorn Class A1 Pacific design. In 1947 Great Northern, up to then the sole member of the class officially designated Class A1, was reclassified Class A1/1 in anticipation of these new Peppercorn A1s.
The rebuilt locomotive had excellent steam generation due to utilising an A4 boiler and had a tractive effort of 37,400 lbf (166.36 kN), which made it one of the most powerful pacifics within the LNER, surpassing the Gresley A4 with only the A2/2 surpassing it. [6] In the same year with only three working months, it achieved 22,052 mi (35,489.25 km) engine miles, compared to the A4 locomotives working in Scotland, which had the highest mileage that year and averaged 57,065 mi (91,837.22 km). [6]
It then went on to become the highest mileage Pacific with an annual figure of 68,304 mi (109,924.63 km), outperforming the next best Gresley Pacific by around 15,000 mi (24,140.16 km). [6] Engine report cards from the LNER archives at the National Railway Museum shows that Great Northern's rebuilt form achieved 55,882 mi (89,933.36 km) per year, matching Gresley A4s and Peppercorn A1s. [13]
For the rest of its working life, Great Northern achieved significantly higher availability than other Pacific classes on the LNER, with its first working year, 1946, achieving 83%. [14] This is partially due to the difference in maintenance approach between the Gresley locomotives, which were often run to failure, while Thompson Pacifics had preventative maintenance and desired high availability. [14]
Great Northern was renumbered No. 113 under Thompson's 1946 renumbering scheme. It then became No. 60113 during British Railways ownership.
60113 was withdrawn on 19 November 1962 with a badly worn cylinder and was then broken up at Doncaster Works. By the time of its withdrawal, Great Northern achieved the highest mileage out of all the Thompson Pacifics and was one of the best locomotives in terms of overall availability for work. [14] An attempt to save the engine from being scrapped was unsuccessful.
PDK Models produce a kit of the A1/1 for 4 mm scale / OO gauge.
The LNER Class A4 is a class of streamlined 4-6-2 steam locomotive designed by Nigel Gresley for the London and North Eastern Railway in 1935. Their streamlined design gave them high-speed capability as well as making them instantly recognisable, and one of the class, 4468 Mallard, holds the record as the world's fastest steam locomotive. Thirty-five of the class were built to haul express passenger trains on the East Coast Main Line route from London Kings Cross via York to Newcastle, and later via Newcastle to Edinburgh, Scotland. They remained in service on the East Coast Main Line until the early 1960s when they were replaced by Deltic diesel locomotives; they themselves proving to be worthy successors to the A4s. Several A4s saw out their remaining days until 1966 in Scotland, particularly on the Aberdeen – Glasgow express trains, for which they were used to improve the timing from 3.5 to 3 hours.
Sir Herbert Nigel Gresley was a British railway engineer. He was one of Britain's most famous steam locomotive engineers, who rose to become Chief Mechanical Engineer (CME) of the London and North Eastern Railway (LNER). He was the designer of some of the most famous steam locomotives in Britain, including the LNER Class A1 and LNER Class A4 4-6-2 Pacific engines. An A1 Pacific, Flying Scotsman, was the first steam locomotive officially recorded over 100 mph in passenger service, and an A4, number 4468 Mallard, still holds the record for being the fastest steam locomotive in the world (126 mph).
The London and North Eastern Railway (LNER) produced several classes of locomotive, mostly to the designs of Nigel Gresley, characterised by a three-cylinder layout with a parallel boiler and round-topped firebox. It produced the most famous locomotive of its day, 4468 'Mallard', the holder of the world steam locomotive speed record. It also built the world-famous 4472 'Flying Scotsman'. However, its locomotive inheritance was much greater than just the 'A4 Class', it also produced highly successful mixed-traffic and freight designs.
London and North Eastern Railway's (LNER) Peppercorn Class A1 is a class of 4-6-2 "Pacific" steam locomotives built between 1948 and 1949 at Doncaster and Darlington Works to a design of Arthur Peppercorn. Forty-nine were built for hauling express passenger services on the East Coast Main Line owned by LNER's successor, British Railways' North Eastern Region. None of the original 49 Peppercorn A1s survived into preservation, with the last being scrapped in 1966. The 50th Peppercorn A1, 60163 Tornado, was completed in 2008 as an evolved member of its class.
Class A1 in the London and North Eastern Railway's classification system may refer to any of the following British steam locomotives :
The London and North Eastern Railway Gresley Classes A1 and A3 locomotives represented two distinct stages in the history of the British 4-6-2 "Pacific" steam locomotives designed by Nigel Gresley. They were designed for main line passenger services and later express passenger services, initially on the Great Northern Railway (GNR), a constituent company of the London and North Eastern Railway after the amalgamation of 1923, for which they became a standard design. The change in class designation to A3 reflected the fitting to the same chassis of a higher pressure boiler with a greater superheating surface and a small reduction in cylinder diameter, leading to an increase in locomotive weight. Eventually all of the A1 locomotives were rebuilt, most to A3 specifications, but no. 4470 was completely rebuilt as Class A1/1.
The London and North Eastern Railway (LNER) Peppercorn Class A2 is a class of steam locomotive designed for express passenger work by Arthur Peppercorn, the chief designer of the LNER after Edward Thompson. All save the first of the 15 built were constructed under British Railways after nationalisation in 1948. Only one example is preserved.
Arthur Henry Peppercorn, was an English railway engineer, and was the last Chief Mechanical Engineer (CME) of the London and North Eastern Railway.
Edward Thompson was an English railway engineer, and was Chief Mechanical Engineer of the London and North Eastern Railway between 1941 and 1946. Edward Thompson was born at Marlborough, Wiltshire on 25 June 1881. He was the son of Francis Thompson, assistant master at Marlborough College. He was educated at Marlborough before taking the Mechanical Science Tripos at Pembroke College, Cambridge, earning a third class degree. Thompson entered the railway scene after education, contrasting that of his predecessor Nigel Gresley, who had also attended Marlborough after gaining practical experience as a pupil at Horwich Works.
The LNER W1 No. 10000 was an experimental steam locomotive fitted with a high pressure water-tube boiler. Nigel Gresley was impressed by the results of using high-pressure steam in marine applications and so in 1924 he approached Harold Yarrow of shipyard and boilermakers Yarrow & Company of Glasgow to design a suitable boiler for a railway locomotive, based on Yarrow's design.
The London and North Eastern Railway (LNER) Thompson Class L1 was a class of 2-6-4T steam locomotives designed by Edward Thompson. The prototype no. 9000 was built in 1945, but the remaining 99 were built under British Railways jurisdiction between 1948–1950. The prototype was well received, however the production batch were not, and all were withdrawn and scrapped between 1960 and 1962.
The London and North Eastern Railway Class P2 was a class of 2-8-2 steam locomotives designed by Sir Nigel Gresley for working heavy express trains over the harsh Edinburgh to Aberdeen Line. As they were to serve on Scottish expresses, they were given famous names from Scottish lore.
The first London and North Eastern Railway (LNER) Class A2 was a class of 4-6-2 steam locomotive designed by Vincent Raven for the North Eastern Railway. Two were built by the NER in 1922 before the grouping and another three by the LNER in 1924. Their LNER numbers were 2400–2404. All five locomotives were named by the LNER.
Willie Brayshaw Yeadon, was a British railway historian known for his magnum opus, Yeadon's Register of LNER Locomotives and other works.
The London and North Eastern Railway (LNER) operated various classes steam locomotives with a 4-6-2 wheel arrangement. The LNER operated more pacifics than any other of the Big Four British railway companies, and they were mostly used for express passenger work along the East Coast Main Line, though later in their lives many were displaced to other lines.
The London and North Eastern Railway (LNER) Thompson Class A2/1 was a class of 4-6-2 steam locomotives built at Darlington locomotive works during 1944. They were originally ordered as Class V2 locomotives, as designed by Sir Nigel Gresley, but were revised during construction into a 4-6-2 'Pacific' arrangement under the instruction of Edward Thompson.
The London and North Eastern Railway (LNER) Class A2/3 was a class of 4-6-2 steam locomotives. They were newly constructed locomotives, fulfilling the requirement identified by Edward Thompson for a standard express passenger locomotive of the 4-6-2 arrangement with 6 ft 2 in (1.880 m) driving wheels. Fifteen engines were constructed according to this original design, but following the retirement of Thompson as CME, the remaining fifteen locomotives that were planned were immediately redesigned and ultimately emerged as Peppercorn Class A2.
The London and North Eastern Railway Class A2/2 was a class of six 4-6-2 steam locomotives rebuilt by Edward Thompson in 1943 and 1944 from his predecessor Sir Nigel Gresley's P2 Class of 2-8-2 express passenger locomotives. The rebuilds improved reliability and reduced maintenance, but also suffered from a variety of issues during service, and all were withdrawn and scrapped between 1959 and 1961.
The Great Northern Railway Class A1 1470 Great Northern was the first of 52 A1 class locomotives. It has also represented three distinct stages in the history of the British 4-6-2 "Pacific" steam locomotives designed by Nigel Gresley for the Great Northern Railway (GNR), a constituent company of the London and North Eastern Railway before the amalgamation of 1923, for which they became a standard design. Eventually Great Northern was completely rebuilt as Class A1/1.