| Power Classification | 2P reclassified 1P in 1953 |
| Introduced | 1899 – 1915 and superheated engines 1920 – 1921 |
| Designer | Pickersgill and Heywood (superheated engines) |
| Company | GNoSR |
| Weight – Loco | 46t 7cwt (superheated 48t 13cwt) |
| Tender | 37t 8cwt |
| Driving Wheels | 6ft 1ins |
| Boiler Pressure | 165psi (later engines superheated) |
| Cylinders | Inside – 18in x 26in |
| Tractive Effort | 16,185lbf |
| Valve Gear | Stephenson (slide valve) |
The Great North of Scotland Railway (GNoSR) was established to connect Aberdeen with Inverness, a target which it never reached due to the hostility of the Highland Railway (HR) based in Inverness. The HR also built a railway line deep into GNoSR territory to reach Keith. Between Aberdeen and Lossiemouth (its furthest point from Aberdeen) the GNoSR built a series of lines serving North East Scotland from the fishing ports of Fraserburgh and Peterhead to the distilleries of Speyside. A separate line (originally entirely separate with its own locomotives: the Deeside Railway) reached Ballater. The main station in Aberdeen was owned jointly by the GNSR and the Caledonian Railway (the North British Railway merely had access to it over the CR).
The GNoSR D40 class was developed from the D41 class by Pickersgill and used the same boiler as the D41 engines. The first thirteen engines (Great North of Scotland Railway class V) were introduced in 1899 and they were fitted with standard boilers. One or two engines of this batch were later superheated.
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D41 class introduced by Johnson in 1893 |
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D40 class introduced by Pickersgill in 1899 |
The GNoSR found itself in financial difficulties after ordering the first ten of these locomotives and they could only afford to take delivery of the first five. The builders Neilson Reid sold the remaining five engines to the South Eastern & Chatham Railway (SE&CR), where they were identified as class G engines, and remained at work until withdrawn by the Southern Railway in 1925-1927.
Interestingly the price that the SE&CR paid for each locomotive was £3,300 which is somewhat higher than the £2,975 paid by the GNoSR.
Pickersgill recommended the purchase of ten more engines in June 1903, which resulted in the purchase of four in December 1906. In March 1911 he recommended the purchase of eight more, but only four were ordered. Both of these latter batches were built at Inverurie.
After the First World War further 4-4-0 locomotives were required to replace aging stock that was due for withdrawal. Heywood had succeeded Pickersgill in 1914, and he designed a superheated version of the class V to meet this need. The eight Class F locomotives were delivered as two batches in 1920 and 1921. The first batch of six engines was built by the North British Locomotive Co Ltd, the second batch of two engines was built at Inverurie.
The D40 class engines were used for the most import express passenger services on the GNoSR until it ceased to exist with Grouping in 1923. This was because the D40s were the last 4-4-0s built by the GNoSR, and unlike other companies they were never superseded by larger 4-4-2 atlantics or 4-6-0s. During this period, they usually worked the line from Aberdeen to Keith and Elgin, although they were sometimes used on through workings to Inverness via the Highland Railway. The Highland Railway was short of locomotives during the First World War, so it preferred to pay an allowance to the GNoSR instead of operating reciprocal services. Although the D40s were the best express passenger locomotives the GNSR possessed, they also had to take their share of goods and branch line workings alongside the other 4-4-0 classes.
The D40 class continued hauling these express passenger trains after Grouping in 1923, but they were joined by ex-North British Railway D31s in 1925. In 1931, they were finally displaced from the heaviest passenger services by transfers of B12 4-6-0s from East Anglia. By this time, the D40s were usually allocated at Kittybrewster, although there were usually small allocations at Keith and/or Elgin. These latter allocations were usually used on the Aberdeen to Elgin main line, as well as the Buchan section, Deeside line, Speyside, and Lossiemouth branches.
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D31 class introduced on the NBR by Holmes in 1884 |
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B12 class introduced on the GER by Holden in 1911 |
The GNoSR served Balmoral Castle via its Balleter terminus on the Deeside line. The reigning monarch usually visited Balmoral at least once a year and these trains were usually double-headed by two class D40 engines.
During the 1930s, the LNER kept a number of locomotives at the Ferryhill LMS shed in Aberdeen for southbound traffic. Resources were often short during busy periods, so a D40 would often be borrowed from Kittybrewster for pilot duties. North British Railway (NBR) custom was to attach the assisting locomotive directly to the train. This resulted in the odd sight of a small-looking D40 being sandwiched between a much larger C11 atlantic and the large bow-ended carriages.
As the numbers of B12s increased on the GNoSR section of the LNER, the D40s were increasingly relegated to branch line duties. Withdrawals started in March 1946, but the LNER only managed to withdraw three D40s before nationalisation of the railways in 1948. At this time, large numbers of Thompson B1 4-6-0s were being introduced, and British Railways quickly withdrew the remaining eighteen D40s between February 1953 and June 1958. Final allocations were usually to sub-sheds including Banff and Macduff.
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B12 class introduced on the GER by Holden in 1911 |
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B1 class introduced by Thompson in 1942 |
Preserved British Steam Locomotives 