Some years ago, whilst on holiday in Munich, we were walking through the Englischer Garten park in Munich – a huge open space in the city – and many years later I discovered that the area was the original home of the firm of J.A. Maffei, and built many 100s of steam locomotives. From these works emerged a couple of well-known examples, such as the S 2/6 and S 3/6 designs for the Royal Bavarian State Railway. The S 2/6 was the holder of the German speed record for steam traction – 154.5 km/h back in 1907, whilst a year later, the Class 3/6 arrived, two of which are preserved in the Deutsches Museum in Munich, and the Transport Museum in Nuremberg.
It was in 1908 that the firm of Maffei in Munich delivered its classic 4-cylinder compound pacific to the Royal Bavarian State Railways, with the class (S.3/6) numbering 145 in all by 1931. These majestic locomotives were used on almost all of the principal services within and extending beyond Bavaria, they were indeed classic locomotives, undergoing a variety of minor design changes and mechanical improvements during their life. In turn though they were the precursors of an equally successful simple expansion pacific, but with only two cylinders, one of which – No. 01 1104 was resident at “Steamtown”, Carnforth in England for a time, before returning to Germany. This was originally DB Class “012″ 4-6-2 No. 012 104 which had been rebuilt with an all welded boiler and converted to oil burning.
The design of their precursors, the S.3/6 compounds was developed by Anton Hammel, Maffei’s Chief designer and, in turn, their appearance owed a lot to the adoption/inclusion of aspects of North American design practices. Amongst these newer features was the adoption of bar frames, with a long, wide firebox. All four cylinders drove the second coupled axle, with the two inside, high-pressure cylinders, set at a slight inclination, with the two outside, low-pressure cylinders set horizontal. The majority of these locomotives were equipped with 6ft 0ins coupled wheels, although 18 of their number, built in 1912-1913 were given 6ft 6ins coupled wheels. Known as “die Hochbeingen” (the Longlegs), one of this class was rescued for preservation in the Deutsches Museum in Munich. Maffei constructed 127 Class S.3/6, whilst Henschel of Kassel built 18 under licence. They were both successful and long lived, with the last of the class being taken out of service in 1965 – 57 years after their arrival in July 1908. This classic Central European style was built on by the following Class 01 pacifics, with another version, Class 03 built with a lighter axle loading constructed throughout the 1920s and 1930s.
In 1920, some 11 years before construction of the S.3/6 4-cylinder compounds had ceased, Deutsche Reichsbahngesellschaft (DRG) was in need of a new express locomotive type, to meet the changing traffic demands. It was in the position of needing to either continue building a proven design such as the Bavarian. S3/6 or the pr. S10 – or alternatively to decide on a new construction.
So, DRG decided to pursue a new approach, by adopting standardisation with the intention of reducing maintenance costs on passenger workings. In essence this resulted in stocks of spares being held at various depots across the network, so that repairs could be undertaken swiftly, by swapping out the failed component, and the loco could then be put back into traffic.
This was essentially how the famous BR 01 and 02 Class of pacifics appeared – Germany’s first ‘standard’ design. Initially 10 of the Class 01 were built, and 10 of the 02 series – the difference between the two was that the 01s were 2-cylinder simple expansion, whilst the 02s were 4-cylinder compounds. The idea was then to compare the performances of each and decide which best suited DRG’s express passenger services going forward – controversially perhaps it was the simple expansion Class 01 design that proved the most effective overall. The stated intention of standardisation was to reduce maintenance costs, and despite the fact that the 2-cylinder design was less powerful and less economical than the four-cylinder compounds, the 01 Class won the DRG’s support.
No fewer than 231 of these locomotives were built between 1926 and 1938, mainly by AEG and Borsig, but also from Henschel, Hohenzollern, Krupp and BMAG. Although strictly speaking, after the initial order for 10, another 221 were ordered, and with the 10 Class 02 compounds converted to 2-cylinder simples between 1937 and 1942, a grand total of 241 of these express locomotives took to the rails. The first 01 to enter service was actually 01 008, and which is preserved today in the Bochum-Dahlhausen Railway Museum.
Their axle load of 20 tonnes (19.9 long tons) was slightly less than the later British Railways ‘Standard’ Class 7 “Britannia” Class pacifics built a quarter of a century later. In Britain though the idea of standardisation was thought of in a different way and was driven by differences between the engineering designs and workshops of the former private railway companies. In Britain the idea being to standardise on the optimum component design produced by the ‘Big Four’ companies, so that valve gear design was adapted from the former LNER, with the larger boiler designs from the LMS.
The Class 01’s axle load of 20 tonnes restricted its use on a number of routes, and this began in the 1930s, along tracks that had been upgraded to take this increased axle load, and in the area around Berlin this required bridge arch strengthening work. Compared to the Bavarian Class 3/6, which had a 16.8 tonnes axle load, they were significantly heavier, and the first 90 engines were sent to home depots from Berlin in the Northeast, across to Essen in the West, Hamburg in the North, and to Nuremberg in the South. Unsurprisingly perhaps, this initial deployment covered the industrial north, whilst later distributions took the class to Cologne, Frankfurt, and Dresden.
The 01s were also modified during the various batches of locomotives built, which included changes such as providing electric lighting for headlamps, instead of gas, increasing the bogie wheel diameter to 1,000mm to enable higher speed, and increasing the braking effort with additional brake shoes. In addition, changes to boiler tubes, smoke deflector designs, and smokebox locking were included in the pre-war modifications.
The major changes, and rebuilding took place in the 1950s, which included such features as water pre-heating apparatus, yet another design of smoke deflector, and the inclusion of combustion chambers. These were done as experiments on locos 01 042, 01 046, 01 112, 01 154 and 01 192. Between 1957 and 1961, the then Deutsche Bundesbahn rebuilt 50 of the class with a new all-welded boiler, roller bearings, changes to the front end frames, cylinder blocks, amongst other modifications. In the East, the Deutsche Reichsbahn in the workshops at Meiningen rebuilt another 35 of the class, also providing a new boiler, pitched higher, and fitted with a combustion chamber and preheater arrangement, along with a new cab and new smoke deflectors.
The class was retained in service in West Germany until 1973, and in East Germany until 1982, with numerous members of the class still operational as preserved examples, in Germany, Austria and Switzerland.
The 01s were a very successful design, and in 1988, the DB Transport Museum in Nuremburg obtained 01 150 for preservation in the national collection. This locomotive was built by Henschel in 1935 and was still in service in the early 1970s, before being taken out of operation on November 13, 1973.
It is beyond the scope of this brief look at a couple of classic German pacific types to provide more extensive detail – but we may return to the subject in a future post.
Perhaps not everyone’s favourite loco, but it was unique in a number of ways, and one of these was the fact that it was the last new locomotive type built at Doncaster Works, which in the early 1980s was part of the soon to be privatised BREL. Its power unit built on the legacy of Ruston Paxman, English Electric and latterly GEC Diesels, which were built at the historic Vulcan Foundry in Newton-Le-Willows – that too was the victim of mass closures and the run-down of the railway industry in the 1980s.
The class 58 had a less than successful career in Britain, and was dispensed with in short order under EWS, and sadly for BREL no export orders were received. But …. It was exported on hire to the Netherlands, Spain and France, where in Spain and France it provided the motive power needed when the high-speed lines were being expanded in the early 2000s, before being returned to the UK, stored or scrapped.
The design and fabrication techniques employed were very much of the mass production line process and should perhaps have been more widely employed in the UK industry, but that was not to be, and it remains a final, and curious example of a good idea that was not fully exploited. There are a number of the class in varying stages of restoration, and one is providing the base for the building of a replica of the first English Electric main line diesel, developed by the LMS and its CME H.G.Ivatt. So the Class 58 legacy remains to be seen in service on specials, and in operation on heritage services.
This small offering is based on my invitation to the handover in December 1982 of the very first Class 58 at Doncaster, where I enjoyed a tour of the works, to see the processes in action, and the unveiling on a bright sunny day of 58001 outside the main office block.
Preserved MR Compound No. 1000 piloting “Jubilee” “Leander” on a Cumbrian coast special to Sellafield, on the May Day Bank Holiday in 1980, passing Dalton Junction, to use the Barrow-in-Furness avoiding line. Photo: Rodger Bradley
In 1948, there were still 40 of the original Midland Railway 3-cylinder compound locomotive design in service, but only one in the Northwest No. 41005 at Lancaster, with the reminder on the London Midland Region’s Midland lines. Of the LMS built engines, there were 69 at Northwest depots in 1950, and out of the total of 223 compounds in B.R. service, 161, or 72% were in London Midland stock. 62 locos. were at work in the Scottish Region, mostly in and around Carstairs, Ayr and Corkerhill, along with Carlisle Kingmoor.
Compound locomotives have not had a particularly happy history on Britain’s railways, but the design based on the Johnson-Smith-Deeley system were more successful than most. the first five locomotives were outshopped with only Saturated boilers from Derby Works in 1902/3, and even following Richard Deeley’s appointment in 1903, as CMEM of the Midland Rly., the compounds continued to be built in unsuperheated form. The original Midland engines were numbered 1000 – 1044, and from 1924 – 1927, and in 1932 (with some modifications), a further 195 were built as the standard express passenger power for the LMS. These locos were numbered 900 – 939, and 1045 – 1199.
Although all 235 locos. were classed as 4P, there were significant mechanical differences that might logically have provided two classes. The basic layout involved two 21″ diameter low pressure cylinders, outside the frames, and a single 19″ diameter high pressure cylinder between, operated by Stephenson valve gear. The boiler was pressed to 200lbs/sq in, and in later Fowler built engines, a Schmidt type superheater was fitted. The original MR locomotives had 7’0″ coupled wheels, whilst the majority, and later LMS standard engines, were only 6’9″ diameter. This in turn, caused an increase in tractive effort from 21,840 lbs to 22,630 lbs, calculated at 80% of boiler pressure in the low-pressure cylinders.
Amongst the characteristic detail features of the compounds, more especially the LMS built locos perhaps, and rebuilds of the first Midland engines, included the straight sided Belpaire topped firebox, and cylindrical smokebox, with door fastened by six clamping dogs. The steam brakes operating cylinders were placed between the coupled wheels, and acted directly on the inner shoes, with a mechanical linkage to the outer shoes, giving a clasp type application of braking force. This was feature of the original series retained in later builds, with the operating arrangement of clasp type rigging used on most modern diesel and electric types.
The most obvious feature was of course the outside cylinders, with a long piston tail rod passing through the front end cover, over the leading bogie wheels. A curious feature of the cylinder layout, perhaps, was the use of slide valves to admit steam from the low pressure receiver to the low pressure cylinders, with a piston valve controlling the admission of high pressure steam to the high pressure cylinder steam chest. A feature of the early locos. which was not continued, was the use of bogie brakes, and the rigging was removed from the engines it was originally attached to; an unnecessary complication tried on several loco. designs in the early years of the 20th Century.
Apart from the style of the chimney, dome and double buffer beam at the front end, typical Midland design was adopted in the construction of the cab, and straight sided six-wheeled tender. This was a Fowler design, based on Midland practice, carrying 3,500 gallons of water, 6 tons of coal, and provided with water pick-up gear.
A major difference between the LMS and Midland engines being that the original locos. were right hand drive GWR style! – the changeover to more conventional left hand drive was made on the 1924 series built by the LMS. With the exception of the coupled wheel diameter, all major external dimensions between the two versions were identical.
In British Railways days, the largest allocation of compounds in the Northwest was at Chester, where, in 1950, 13 were stabled, whilst Llandudno Jct. with 10 engines, was a close second. No less than 15 Northwest depots shared these 70 compounds, with the majority on the Manchester to Crewe, and Chester to Holyhead lines. The only representative of the original Midland Railway design was stabled at Lancaster, as B.R. No. 41005, and has some interesting points in its operational history. It was the first of the batch built by Richard Deeley, which covered locos. 41005 – 41044 and was rebuilt by Henry Fowler in 1932 with a superheated boiler, Ross ‘pop’ safety valves, and a typical Fowler steam dome which had a slightly flattened top.
By the mid 1950s, withdrawals had reduced the number of compounds in service to 56 (1954), out of a total on the London Midland Region of 131, just less than 43% of the total operating stock. However, by the end of the 50s, they had almost completely disappeared, with only 18 left at the beginning of 1959, and none of these was from the original Midland Railway build. Of course, by that time 41000 had been preserved at the Clapham Museum as No.1000, in fully lined LMS crimson lake livery.
Speaking of this, it remains a curious fact that although classified as a passenger type, they never appeared in British Railways lined green, which could have been an attractive scheme.
Instead, like some of the passenger tanks, and the ‘Black Fives’, they appeared in mixed traffic lined black colours, with the early British Railways lion and wheel emblem/totem in the middle of the tender sides. As far as I know, none of the compounds received the later style of crest, which appeared from 1956 onwards.
No allocations for 1964, since no compounds were then in service. Of the 75 remaining on the London Midland Region in 1954, almost one third were at work in the Birmingham area, with the remainder on the St Pancras to Manchester line, and a few in and around Leeds.
If there was such an animal as a typical Midland locomotive, then surely Henry Fowler’s class 4 passenger tanks were in that category. First built at Derby Works from1927, many of the class came to the northwest, in BR days particularly, although it was not until the early 1960s that there were ever more than half the total allocated to this area.
NB: The heading image shows Banks Station, with the 17.59 from Preston, headed by LMS Fowler 2-6-4T No. 42369. This is a classic Fowler working on this Preston – Southport train, looking eastwards, towards Preston. The line and station was closed on 7/9/64 – less than two weeks after this photograph.
They were intended for heavy suburban and intermediate passenger work, and classified 4P, with steam pipes inside the smokebox on the original 1927 build. Modifications introduced in 1930 included outside steam pipes, side windows in the cab, and an altered smokebox saddle, with a solid bottom to the cylindrical wrapper.
This latter, with outside steam pipes, was essentially adopted to eliminate a. corrosion problem, where the steam pipes had passed through the bottom of the smokebox and saddle.
In general, the modified locos. were the same as the earlier version and covered by diagram ED172C. The parallel boiler was retained, supplying two outside cylinders, operated by Walschaerts valve gear, with long travel inside admission piston valves. Other minor modifications included the provision of’ cast steel axleboxes, compared with the earlier, manganese bronze variety. The original cab and gangway door arrangement contributed to the draughty nature of the footplate, and the large gap behind was partially closed, and some locos. were fitted with folding doors. In early BR days, a number of engines we refitted with new, cast steel cylinders.
Operationally, the class was a success from the word go, and have been reported by some sources as “excellent performers”.They were more economic to run than the later Stanier designs, on faster, heavier and more demanding duties. On building they were allocated numbers previously carried by a variety of, pre-grouping types, including North Staffordshire and Midland Railway 0-6-0s. In the north west they were assigned to duties originally undertaken by the Hughes, ex L & Y, Baltic tanks, where they proved highly successful. There were though, some curious differences in mileages run between general repairs. The engines allocated to Scotland for instance, were able to work 240,774 miles between repairs, whilst in England the figure was only slightly more than half this.
In service with British Railways, the locos. were reclassified as mixed traffic, with just less than half allocated to northwest depots. Of these, the majority were stabled in South Lancashire, North Cheshire and Derbyshire. The engines sent to Oxenholme and Tebay were mainly for banking assistance on the climb to Shap, whilst the Furness line’s passenger duties were very largely powered by these class 4 tanks. By the mid 1950s, Buxton, Alsager and Tebay had lost their stock, though they could still be seen in some strength in the Potteries, North Cheshire and around Manchester. Macclesfield for example had maintained a stud of 11 Fowler class 4’s for many years, but by the early 1960s they had been withdrawn.
The class total too, was dramatically reduced at this time from 125 to a mere 16 in 1964, and were completely extinct soon after.
The livery carried in British Railways days was mixed traffic black, lined red, cream and grey, with at one time or another, both designs of lion and wheel symbol being applied to the side tanks. They were, in this guise, a very attractive engine – what a pity only the Stanier and Fairburn types are represented in preservation.
1950 = 125, with 62 or 49.6% at northwest depots.
1954 = 125, with 53 or 42.4%at northwest depots.
1964 = 16, with 12 or 75.0% at northwest depots.
Further reading & Useful Links
“LMS Locomotive Profiles No. 3: The Parallel Boiler 2-6-4 Tank Engines” – David Hunt, Bob Essery Fred James (2002) ISBN1-874103-72-0
“Engines of the LMS built 1923–51” – Rowledge, J.W.P. (1975). Oxford: Oxford Publishing Company. ISBN0–902888–59–5.
In the 1930s, the English Electric Co. were busy designing and building diesel engines for railways – mostly around the former British colonies, but the impact of the economic depression had Britain’s railways looking for efficiency – especially for use on shunting operations. But English Electric had for some years been at the heart of technology innovation and development and had been trying to persuade the more conservative railway operators to look to the future.
The company developed a diesel-electric version of the classic 0-6-0 steam shunting locomotive, powered by a 6-cylinder diesel – or as the press referred to it an ‘oil-engine’ – to sell the idea to either the LMS, GWR, LNER or Southern railways. The LMS was first out of the blocks and with English Electric as the engine supplier, with Derby constructing the mechanical parts, they embarked on an ambitious project to tap into the benefits of diesel power for shunting work. They were followed by the GWR and Southern Railway, and the latter followed the English Electric power plant path, whilst the GWR had opted for a variety, including Davey Paxman engines.
20 years after the first LMS shunters began to appear in the early 1930s, in 1953, British Railways placed orders for what became the standard shunting locomotive – the 350hp, or Class 08 type. Hundreds of these were built, mainly at Derby, Crewe, Darlington, Doncaster and Horwich Works with a pair of d.c. traction motors driving the wheels, which were linked by coupling rods, exactly as a steam loco would have been. Ultimately, 996 of these 0-6-0 shunters were constructed at the railway works – some were built at English Electric’s works in Preston, and Vulcan Foundry at Newton-Le-Willows (mainly for Netherlands Railways).
At nationalisation in 1948, British Railways inherited a motley collection of 60 of the 0-6-0 diesel shunters – 46 from the LMS, 7 from the GWR, 4 from the LNER and 3 from the Southern. Of these all, bar one had an English Electric 6KT diesel engine and traction motors, and that exception was the 1934 Armstrong Whitworth built loco, with a Paxman engine and a mechanical drive through jackshafts from its single traction motor.
The Harrier HydroShunter project to convert locomotive from diesel to hydrogen traction will take ex BR Class 08 shunter No. 08635 and remove the English Electric engine and generators, to be replaced by a hydrogen fuel cell stack and battery, as a hybrid installation. The project is unique and involves the University of Birmingham, Vanguard Sustainable Transport Solutions, and the Severn Valley Railway.
It’s a brilliant idea, and if successful could pave the way for similar replacements at home and abroad, and whilst passenger trains for commuter services have seen similar projects highlighted, such as the conversion of Class 314 for the “Hydroflex” train, this has perhaps just as wide ranging potential. Following the earlier projects, the traction system being designed by Vanguard at the University of Birmingham, this hybrid system will consist of a hydrogen cylinders, a fuel stack where the electricity is generated and a battery.
The loco was formerly D3802, built at Derby in December 1959, and renumbered in January 1974 and withdrawn from BR service in December 1981. It is currently at the SVR’s Kidderminster diesel depot, and the team of volunteers have removed the diesel engine and generator, and have been busy renovating and overhauling other key components. The SVR had to hire a 100-tonne crane to lift the diesel engine out of the shunter, and the work is now well underway to achieve trials later in 2021.
The new power unit includes pressurised hydrogen stored in cylinders for supplying to the fuel cell stack via a regulating device, oxygen from the atmosphere will then be mixed, and electricity generated and delivered to the loco’s traction motors. The battery will also be charged by the fuel cell stack, to provide energy reserves as and when needed. The existing traction motors, controls and final drive is being retained, with the new equipment fitted to a new sub-frame, which in turn is mounted to the existing engine-generator mounting points.
Of course, with the hydrogen fuel-cell power, emissions are zero compared to the old diesel engine, and it has been suggested that there will be a reduction in maintenance costs of possibly 50%, which if it is successful could see many more similar retrofit projects. Although, whilst we may be at the start of a new era in terms of non-electrified traction, as the fuel cell technology evolves, it may be that larger locomotives could see similar replacements. This might not see huge numbers in countries where expenditure on electrification has been significant, but in other countries, where funds are lower, it could provide opportunities – providing the capital costs are also low.
There are of course some disadvantages to hydrogen as a fuel, mostly in terms of the way it is produced, and its storage – according to one source (https://www.theengineer.co.uk/comment-hydrogen-trains-uk/ ). “Firstly, hydrogen storage is bulky. Even at 350bar, the volume of fuel needed is eight times that of Diesel.” The author goes on to state that that could be a problem for long haul freight services, and would be unsuitable for high-speed rail, on account of the amount of electrical energy required, and the losses developed in the power unit. But, it is being considered for some types of rail passenger service, in order to remove the dependence in rural area on diesel multiple units.
It will be fascinating to see this project completed, and what might develop over the next few years, and whether the technology does play a part in maintaining the railway’s place as a sustainable mode of transport.
There is a famous rail route that runs over 1,800 miles from Adelaide / Port Augusta in South Australia to Darwin in the Northern Territory by way of the equally world-renowned town of Alice Springs. The history of railway development in Australia might be described as a patchwork of different shapes, sizes, lengths and ownership, and this route is also home to the “The Ghan Express”, or more commonly “The Ghan”, which has an equally chequered history.
The line was built in various stages between 1879 and 1929 – by which date it had reached Alice Springs – was opened between Port Augusta and Alice Springs as the Central Australian Railway and built to the narrow gauge of 3ft 6ins – thus adding to the country’s complement of rail gauges. In fact, even before the full route had been opened, the Central had been taken over as a section of the Commonwealth Railways, which was already operating the standard gauge route from Port Augusta to Kalgoorlie.
The story of the line from South to North in Australia is fascinating one, and the line where ‘The Ghan’ operated – and indeed operates to this day as a private company is even more interesting. But, as I’m sure many of us will remember from school geography, the continent of Australia is very dry, and posed many problems for steam train operations – especially on this route – so it was something of a blessing when diesel traction arrived.
In this example, which is one of international co-operation, no less than three separate companies were involved in the design and construction of 13 diesel locomotives for freight and mixed traffic duties. The power units were supplied from Barrow-in-Furness, on the south-western extremity of the English Lake District, from Vickers Armstrong’s engineering works, and electrical equipment from AEI in the midlands, with the whole package put together by Tulloch in Australia.
General Design & Ordering
The basic design of these locomotives was a joint effort between Sulzer in the UK and SLM in Switzerland, with the overall operational needs laid down by Australia’s Commonwealth Railways to run on the 3ft 6ins gauge line from Port Augusta to Alice Springs. The locos needed to operate in a harsh environment, with a hot dry climate and temperatures that exceeded 100 deg F for days on end, and frequent sand and dust storms. On top of this they needed to run on lightweight track – 60lbs/yard – with demanding curves in places.
The effect of the weight of the locomotive and train speeds demanded particular consideration with the bogie design to minimise rail stress, and the effect of bogie movement and axle loads. Compared with the ‘Zambesi’ design delivered around the same time, the NT Class was some 12tons lighter.
The order for three locomotives was placed in 1964, and many aspects of the design, including the power unit were based on an design that Sulzer-AEI had already supplied to Africa for the Nyasaland and Trans-Zambesia Railway in 1962/3. In March 1964, Nigeria placed an order for 29 of the same ‘Zambesi’ design, again using the same Sulzer 6LDA power unit, which was the heart of the NT Class design ordered from Sulzer in the same year.
The bodies of these locomotives had a very different design and construction than many of the more conventional designs of the day – as a rectangular full width box, the bodysides were created as stressed skin forms, or semi-monocoque. Fabrication of the assembly used rolled steel sections, covered with sheet steel panels, and to provide the rigidity against deformation, a series of closely spaced vertical pillars and horizontal rails was used.
This provided a fully integral structure, with the bodysides connected by headstocks, bolsters, crossbars, deck plates, and bulkheads separating the cab at one end from the radiator compartment and engine room. The coupler height was a particular issue with the NT Class and to handle buffing loads of up to 150 tons, a triangular fabrication was installed at each end behind the drawgear.
Immediately behind the cab was a full width 3ins thick bulkhead, heavily insulated, and the door into the engine room was double glazed, to provide protection for the crew from excess noise and heat. The radiators were positioned on either side, with part bulkheads to provide extra stiffness in the body, and similar, part bulkheads were provided at the other end of the engine room, separating the control equipment from the engine and generator. Beyond these bulkheads was the ‘free’ end of the engine.
In its final form, the cab was placed at the No.2 end of the loco, although there had been some consideration of the design having a cab at each end. The reason given for the cab at the No.2 end was again to do with the nature of the track it would run on, and having the cab at the No.2 end would make for better weight distribution. Another interesting departure from the original design in the NT class was that after the first order was delivered, the following two orders and 10 locomotives were built with a body some nine inches wider.
The engine, an uprated version of the 960hp 6LDA28 series fitted into Class NSU locos, was exhaust pressure charged and intercooled, delivering 1,400hp, and running at 800 rpm. At the time of their construction 4-stroke medium speed engines were commonly used in the UK and many countries, and the Sulzer engines were all built in the Engineering Works of Vickers-Armstrongs in Barrow-in-Furness. By the time these engines were built in Barrow, the works had already constructed around 1,000 of 6, 8 and 12 cylinder types for British Railways, and of course many for other countries, including the ‘Zambesi’ design for Africa.
For the NT Class though, fitting the engine and generator assembly in the body of the loco really drove the design, since to meet the height requirement specified by the design it was necessary to mount the engine below the deck plating. This meant that a conventional underframe could not be used, and the loco’s bodysides would be the main load bearing elements, taking both traction forces and equipment loading through cross stretchers. Hence the stressed skin technique.
The engine itself required major changes to the workplace at the Vickers site in Barrow, and a large proportion of the engineering output there was focussed on building diesel engines, including marine types, along with cement plant, boilers, armaments and equipment for nuclear submarines. In fact Vickers, Barrow first Sulzer engine order was received in 1947, but in 1955 orders began to be received in large numbers from British Railways, which led to the company creating a separate Traction Division to manage the design, build, testing and inspection of the Sulzer engines. According to a commemorative brochure to mark the 1,000th engine:
“The manufacture of Sulzer engines can generally be undertaken on general purpose machine tools but specialised techniques have been developed to assist the large scale productions and inspection of these engines. Extensive use is made of jigs and tools to ensure the interchangeability of all finished parts.”
In the 1960s, Vickers, Barrow was a very busy works, and by the time the Australian order for 6LDA Sulzer diesels arrived, they had already built 1,000 of the Sulzer LDA design. The power unit was used in the earlier A1A-A1A locos built for Commonwealth Railways over a decade earlier.
As a 4-stroke design, Sulzer engines were already easy on fuel, but for the Australian order, the ‘Zambesi’ variant provided lower fuel consumption, and showed good consumption over the full working range. The cylinder block was described as being “… of the wet liner type …” with a single camshaft on the outside operating the valve gear and fuel injection pumps. Fibre glass inspection panels and a full length steel cover on each side of the engine provided access to fuel pumps and crankcase. The latter was built from a number of transverse cast steel members welded to mild steel fabricated longitudinal elements.
The engine was completed by being mounted on side girders, fabricated in a box section, and extended at one end to provide a mounting for the generator. The design and manufacture of the engine provided a significant contribution to reducing the overall weight, and the subsequent impact loading on the lightweight rail used on the narrow gauge networks. In addition, by comparison with the NSU Class, the new locomotive’s power unit provided some 50% more power, and had been tested to achieve a 1,540hp over 1 hour on test at the Test House in Barrow.
The electrical equipment – generator and 6 traction motors were supplied by AEI. The generator, an AEI TG 5302W was mounted at the far end of the loco from the cab and connected to the engine with a solid coupling. The generator armature shaft connected to an auxiliary drive gearbox mounted on the main generator’s end frame of the main generator in a clover leaf format and provided three separate auxiliary drives. One of these was located vertically above the main generator shaft, the other two below to the left and right respectively. The auxiliary generator provided power for lighting, control systems and battery charging.
Immediately behind the cab/engine room bulkhead the cooling radiators were sited on either side of the loco, together with the combined fuel, lubricating oil and water pump set. For cooling the engine only one circuit was used for cooling the engine, lubricating oil and charging air. The advantage claimed by the builders for this simple system was that under all conditions of load the temperature of the engine water, lubricating oil and charging air would be kept at the correct value. This equipment was supplied by Serck and claimed to provide ample margin for operation under the extreme climate conditions of the line.
With so few partitions and bulkheads, ventilation of the engine room was an important aspect of keeping operating and maintenance costs low, as well as combating the harsh environment. The outside air was drawn from the top of the roof at the rear end of the locomotive through an axial flow fan and passed through filters into the engine compartment, effectively providing a positive pressure environment, to exclude fine dust and sand. Additional air flow was provided via the traction motor blowers.
Running Gear and Transmission
Below decks so to speak, the locomotive body and power unit was carried on a pair of 3 axle bogies. The bogie proper was a mixture of cast and fabricated components in a design intended to provide a good ride quality, with the metal-to-metal contact elements replaced by in rubber, and other non-metallic materials. The basic assembly followed the same pattern as the ‘Zambesi’ class for Africa, where rolled mild steel sections and plates were welded into sub-assemblies to form a box-section frame.
Primary springing used helical coil springs between the equalising beams and the bogie frame, with four sandwich rubber units widely spaced providing secondary springing, and hydraulic dampers fitted at each primary spring location. The secondary springing also reduced the weight transfer during periods when the loco was working hard or exerting higher tractive effort.
The bogies of course carried the clasp type brake gear, and this was operated by Australian Westinghouse air-brake system, and followed standard Commonwealth Railways practices. Another weight saving aspect of the design was the aluminium fuel tank, which was “U” shaped in order to allow space to fit the inter-bogie control mechanism. This latter’s purpose was designed to reduce the wear on tyre flanges when running through tight curves, by ensuring the wheels were at the best angle to the rail. This assembly consisted of a pair of yoke arms, running on rollers supported by a body mounted bracket, with the yoke arms on each bogie were connected by a coupling. The braking system on the new NT Class was pretty standard for the 1960s, with clasp type tread brakes and rigging, operated by Australian Westinghouse supplied air-brakes.
Each bogie carried three AEI Type 253AZ 149hp traction motors driving each axle, in the conventional nose suspended, axle hung arrangement. Again, these were the same as fitted to the ‘Zambesi’ design – 4-pole, series wound, and with 3 pairs permanent connected in series, with three stages of field weakening. The final drive to the wheels was achieved using a pinion on the motor shaft driving the axle mounted solid spur gear wheel with a ratio of 92/19, and the whole assembly was enclosed in a sheet steel casing.
Overall control is electro-pneumatic, with the relays/switches located in the control cubicle at the ‘B’ end of the locomotive providing the operation of the different stages of traction motor field weakening. The cubicle was effectively sealed from the rest of the engine/generator compartment and supplied with air taken from the traction motor blowers, at a slightly higher pressure.
The output from the engine to the main generator used a hydraulic load regulator, linked to the engine governor, and an 18 notch master controller, mounted in a pedestal style in the cab regulated the engine speed and power. The train crew were provided with a range of visual and audible alarms for earth faults, wheel slip, high water temperature and low oil pressures, amongst other alarms.
The NT Class were equipped to operate in multiple, and up to three locos could be coupled together and driven from one cab, whilst it was also possible to operate in multiple with the earlier NSU Class A1A-A1A design. It was claimed at the time of their introduction that, at 1400hp, they were the most powerful diesel locos for their weight anywhere in the world.
Numbering & Operations
The first order for the three new NT Class locos was driven by increased passenger and freight traffic, and as a result Commonwealth Railways placed its order for a locomotive type with Tulloch Ltd of Rhodes, Sydney. The design needed to be innovative because of the quite badly laid 3ft 6ins gauge tracks of the Central Australia Railway. The first three were set to work on the section of line between Maree and Alice Springs.
Overall, at first glance, the orders for the NT Class appear quite haphazard – the first 3 in 1964, then an order for 3 more in 1966, and a final order for 7 in 1968, bringing the total to 13. The second order was placed to meet an expected increase in iron ore traffic from the Frances Creek mine on the Northern Australia Railway, and as the tonnage taken out of the Frances Creek mine continued to increase the third order was placed.
The first of the new 1400hp diesels was delivered to the Central Railway for service on the demanding route through the Flinders Range mountains between Port Augusta, Maree, Oodnadatta and Alice Springs. When NT65 was delivered in April 1965, it was decided to name the first of the class after the then Transport Minister- Gordon Freeth – and it remained the only named example of diesels on this route.
NT65 to NT67 were delivered from the Tulloch Works on standard gauge transfer bogies to Broken Hill, where the 3ft 6ins gauge bogies were fitted, and working initially from Quorn, through the Pichi Richie Pass to Port Augusta. In addition to passenger traffic, the coalfields to the northwest of the Flinders Range provide significant freight traffic, and where before a pair of the older NSU diesels would be used, the same working would need only a single NT.
The same process was followed for delivery of the remaining locomotives between 1966 and 1968, and, given that the standard gauge route to Alice Springs was by then in operation, the NTs destined for the Northern Railway were shipped overland from Alice. This involved removing the NTs bogies, and carrying the three new locos on low loaders across country along the Stuart Highway.
The second order for three more NT class locos were sent to the Northern Railway, which were joined by another five from the third order. The remaining two NTs were retained for duties on the Central Railway. The final seven were all intended for the Northern, as the output of iron ore continued to grow rapidly, and which led to the transfer of one of the class on the Central – NT67 – as a temporary measure.
In 1971 the Central was again seeing some new motive power – the Clyde built NJ Class locos, which allowed for the remaining NTs to be sent to the Northern, where they saw out their final years.
The Northern Railway was just over 300 miles long from Darwin to Birdum, but no connection to Alice Springs. In the south, services operated over the Central Railway consisted of passenger and freight, running from Port Augusta to Maree, on to Oodnadaata and finally Alice Springs, a distance of over 770 miles.
Iron ore from the Frances Creek was at the heart of a very serious accident, with no fewer than four NT Class engines involved on 4th November 1972, and which led to the loss of three complete locomotives, and damage to the fourth.
The Darwin Accident
This was the Northern Territory’s worst rail accident and involved four NT Class locos, and this recorded quote provides an interesting description:
“Just after 5am on a November morning in 1972, a train fully loaded with iron ore crashed into a stationary train at Darwin’s Frances Bay rail yards. One railway official said, “I never saw anything like it. I ran down there expecting to be pulling bodies out of the wreckage.” But incredibly, there were no casualties, even among the crew of the runaway train, who had realised it was out of control and jumped out in time. However the accident destroyed over $1 million worth track and rolling stock.”
The locos involved were NT68, 70, 71 and 75. NT70, 71 and 75 were written off after the accident, and although NT68 survived, it survived only another 6 years in service, and was scrapped in 1978.
In 1911 the Northern and Central Railways were owned by the Commonwealth Railways, and operated as Commonwealth Railways since 1926, and 50 years later – a decade after NT65’s arrival – four were operating on the Central and the remaining nine on the Northern, all subsequently became assets of Australian National.
For the NT Class locos it could be argued, their time was almost up before they were put to work, since with the closure of Central Railway in sections from 1957 to 1972, the majority of ‘narrow gauge’ workings took place in the Northern Territory. All of the NT Class were transferred north in the 1970s, but not for more than a few years, until 1976.
By 1976 the Northern Railway was closed, leaving NT’s redundant, and with the closure of the vestiges of the 3ft 6ins route from Alice Springs to Maree in 1981, there was nowhere for them to go. Except, there were still trains to haul on the Eyre Peninsula Railway, in what became South Australia’s Port Lincoln Division. The remaining NT’s were joined there by the six newer NJ Class that were delivered to the Central Australia line from 1971.
One of the NT Class locomotives has been rescued and preserved on the Pichi Richi Railway. NT76 was officially withdrawn in 1989, and is now operational on this heritage railway, along with an older sibling from the NSU Class. The Pichi Richi Railway has its headquarters at Quorn and operates through the Pichi Richi pass in the Flinders Range down to Port Augusta.
So we know of at least one Barrow-in-Furness built Sulzer diesel engine that is still operational – some 12,000 miles away – and approaching its 60th birthday on the picturesque and dramatic line that was home to the original “Ghan Express”.
I am indebted to the Pichi Richi Railway, Jeremy Browne, Julian Sharp and Chris Carpenter for additional information, and some excellent images whilst researching this small offering on what you could say was a tenuous connection between Barrow-in-Furness and Alice Springs. The vastness of the Australian interior, and the amazing work of the people who designed, built and completed the railway across the continent was matched by the diesel engines, train crew and everyone involved in operating a railway in such a hostile environment. Thankyou.
Almost 50 years ago, the WD/MOS 2-10-0 that had been used by the ‘Royal Engineers’ on the Longmoor Military Railway (LMR) was retired to the Severn Valley Railway, where it sits today in the museum at Highley Station. This engine was one of 150 locomotives built by the North British Loco. Co., in Glasgow between 1943 and 1945, which were all originally destined for overseas service with the Allied Army after D-Day to provide supply chain and European recovery and restoration. The Ministry of Supply (MOS) had placed two orders with North British – L945 and L948 – and the majority of these were sent to France, Belgium, Netherlands, Greece and the Middle East.
Some were sent to Egypt, where they were stored for a time, before dispersal to Greece to help rebuild the transport infrastructure, with a handful seeing service in Syria. The lion’s share were leased by The Netherlands – 103 in total – and were used on freight workings until 1952, and had some changes to the original design, most notably in the boiler and steam circuit. In 1948, British Railways acquired 25 of their number, which were put to work in Scotland until 1962, when they were all withdrawn.
These ‘WD Austerity’ engines were not particularly well liked, or successful in the UK, but many aspects of their design principles were later adopted in the design and construction of the BR ‘Standard” series locomotives – not so surprising really considering that the designer, on behalf of the wartime Government was R.A.Riddles.
The WD 2-10-0s were only the third example of ten-coupled locomotives in this country. The first being the Great Eastern’s “Decapod”, which was converted unsuccessfully in 1906 into an 0-8-0 tender type. The second example was still running at the time the WD ‘Austerities’ were introduced – this was the LMSR 0-10-0 No. 2290 used for banking on the Lickey Incline. However, the only similarity between either of these examples and the MOS type was the coupled wheel arrangement. Both of the earlier types were designed with a specific purpose in mind, whereas the WD 2-10-0 was intended for use on all types of freight duties over varying qualities of permanent way, and even in the restricted confines of marshalling yards.
One of the class No. 90764 found its way south of the border in 1950 to the Rugby Test Plant, and controlled road tests were carried out in 1953/4 with engine No. 90772, on the Scottish Region, between Carlisle and Hurlford, near Kilmarnock. The tests were carried out in company with WD 2-8-0 locomotive No. 90464, and ultimately became the subject of the BTC Test Bulletin No. 7.
Four of these WD 2-10-0s have been saved – ‘Gordon’ from the LMR is still on the Severn Valley Railway, 90775 is on the North Norfolk Railway, and named “The Royal Norfolk Regiment”, whilst a third – 73672 – is undergoing restoration on the North Yorkshire Moors Railway, both of which were repatriated from Greece. The last of the preserved locos is 73755 and named “Longmoor”, complete with Royal Engineers badge, and is now on display in the Netherlands Railway Museum in Utrecht.
Details of the design of the loco and construction of the 25 that were purchased by British Railways in 1948 are outlined in the booklet below – just click on the image to read or download.
The 1980s saw some notable achievements by the U.K. rail industry, in particular, the decision to introduce two more new classes of electric locomotive, with the most advanced technology, on British Rail’s west and east coast main lines. On board microcomputers were introduced in ever increasing numbers, in the control systems of new multiple units like the class 318 and 319, and the class 87/2 (later Class 90) and 91 ‘Electra’ locomotives. With the announcement of’ the go-ahead for the Channel Tunnel, a consortium of U.K. manufacturers, including Brush, GEC Traction., Metro-Cammell and BREL, were quick to announce plans for motive power for the through trains, planned for operation between Britain and the rest of Europe. These latter saw the beginning of the end of the d.c. motor as the standard form of power transmission to a locomotive’s wheels, extending further the use of power electronics into rail traction service, with a.c. motor drives.
Whilst the major companies like Brush and GEC Traction regularly supplied British Railways with locomotives and power equipment, with the latter winning the major contracts for1986, the U.K. industry was equally successful overseas. In the main, a substantial number of orders involved rapid transit rolling stock, taking in other household names in the British railway industry, like BREL, and Metro-Cammell, although exports of locomotives and power equipments did not lag far behind.
The major successes in that decade for the export market again involved GEC Traction and Brush, with the latter handing over the first of 22 new locomotives in 1986, for the North Island electrification project in New Zealand. GEC’s most important export contract at that time was worth some £35 million, for 50 class 10E1 electric locomotives for South African Railways. On the whole, the 1980s continued to witness export success for British companies, in many fields, against some very stiff competition.
In 1984, Brush Electrical Machines received an order for 22, 3000kW Bo-Bo-Bo locomotives, as part of a £30 million contract placed with Hawker Siddeley Rail Projects by New Zealand Railways Corporation. First deliveries were originally scheduled for December 1985, but the official handover of the first of the new locomotives did not take place until April 1986.
New Zealand’s latest motive power is finished in a striking red livery, with yellow ends, black underframe, bogies and roof, and operated on the 3ft 6ins (1067 mm) gauge of the North Island’s electrified main lines. Taking power from the 25kV a.c.,50Hz overhead contact system, these 22 locomotives from Brush incorporated some of the latest thinking in rail traction technology. The monocoque body, with a driving cab at either end, housed the main transformer, traction converters, and all auxiliary equipment. The overall design of the locomotives was prepared in accordance with specifications provided by New Zealand Railways Corporation, with their principal workings planned tor the Palmerston North to Hamilton sections of the North Island main line.
The solitary, single-arm, air-operated pantograph mounted in a shallow roof well collected power from the overhead catenary, feeding the main transformer through a roof mounted vacuum circuit breaker. The transformer itself was oil cooled, and mounted in the centre of the loco., with outputs from the secondary windings feeding the two thyristor, traction converters. From these, d.c. supplied the six, axle mounted, 500kW traction motors. The power control electronics, in addition to providing stepless control of tractive effort, also allows for regenerative braking, with the traction motors acting as generators, and returning power back into the overhead line.
The traction motors have separately excited field coils (sep-ex), with force ventilation., and represented the then current thinking in d.c. traction motor technology; their continuous rating of 500kW was reached at a speed of 910 rpm. Sep-ex motors enabled better use to be made of a traction unit’s available adhesion properties, along with more precise control of wheelslip, through the preferred arrangement of power control circuits.
Each of the three bogies in the N.Z. locos had a wheelbase of 2500mm (8ft 2ins approx., if you prefer) at bogie pivot centres of 5850 mm (19ft 2ins), with main and secondary suspension provided by coil springs. The bogies sported traditional air-operated clasp type brakes, in addition to regenerative braking, with the shoes bearing directly on the wheel treads.
Basic dimensions and data are as follows;
GEC Traction’s connection with South African Railways goes back many years, including numerous orders in a fleet of electric locomotives that constitute the largest single type in the world. In 1985 the company won an order for 50 claas10E1(series 2) 3kVd.c. electric locomotives, worth some £35 million. At that time, the S.A.R. class 10E1’s were the most advanced d.c. traction units in the world, incorporating state of the art technology. The order was placed with GEC Transportation Projects of the U.K., with mechanical parts supplied by Union Carriage & Wagon Co., of South Africa.
Weighing in at 126 tonnes, these Co-Co units included microprocessor based ‘chopper’ control, and up to six could be connected in multiple, with a continuous rating of 3,000kW each – the same as the New Zealand triple Bo locomotives built by Brush.
Basic dimensions of the SAR locomotives are given below, and are worth comparing with the Bo-Bo-Bo units for New Zealand;
Power equipment installed in the 10E1 locomotives was designed to cover supplies from 2kV to 4kV d.c., with each of the two single arm pantographs connected to high-speed circuit breakers. Equipment layout in the locomotive body was based on a modular and functional grouping arrangement, where the obvious advantage is in the reduction in complexity of pipework and cable runs, and easier maintenance. The two fixed frequency choppers are air cooled, and the three thyristor arrangement was similar to installations provided by GEC on multiple unit stock for the Dublin and Seoul (Korea) metro schemes.
Again, like the Brush locos. for New Zealand, d.c., traction motors with separate excitation of field coils was provided, with the six motors connected in two groups of three motors in series. Individual control of the two motor groups allowed compensation of wheel wear, and reduction of the effects of weight transfer. In a similar manner to the numerous class 6E1 locomotives, the traction motors were mounted on a ‘U’ tube suspension unit and axle hung. Regenerative braking, and when required, rheostatic braking was included, independently controlled from the air brake system operating conventional clasp type tread brakes. Auxiliary power supplies were 3-phase a.c., supplied from a single motor alternator set.
The microprocessors that form the heart of the sophisticated control system provided rapid detection and correction of wheelslip not automatically corrected by the sepex motors, load sharing between locomotives connected in multiple, and the weight transfer compensation. One of the features of the microprocessors was enabling the new units to operate in multiple with other types, by storing the operating characteristics of the different types, and matching the performance of the 10E1 type to suite. As with all locomotives fitted with microprocessor control, fault monitoring, diagnosis and logging, was an important feature, and eventually a standard facility.
Designed for operation in some very arduous environmental conditions to exacting technical specifications, the first of the new SAR locomotives entered service in late 1986.
Again, both Brush and GEC Traction figured prominently in diesel traction equipment for the export market, joined by others, such as Thomas Hill and Hunslet, with specialist diesel shunting locomotives, primarily for industrial use. Brush, who are most familiarly associated with numerous class 47 and HST, and later the class 56 units for British Rail, saw success in 1980 with a £1 million order from Japan for diesel-electric shunters.
And, in the early 1980s, following completion of a new purpose-built locomotive assembly shop at Loughborough, the Company concentrated efforts on building up sales of a range of shunting and trip working locomotives. For Turkey, Sri Lanka and Ghana, Bo-Bo type locomotives were built between 1981, 1982 and 1983, of a relatively similar basic layout, but some variations in detail design. Also in 1983, Brush’s links with India were reinforced with an agreement covering the development and construction of shunting locomotives with Suri & Nayar of Bangalore.
The Bo-Bo locomotives which Brush were building for Sri Lanka in 1982 were a hood type, housing a 1000hp General Motors diesel engine coupled to the main alternator, with four conventional series-wound traction motors. The general-purpose locomotives were essentially an orthodox hood type, with a major feature of the designs being the elimination/reduction of maintenance, through the provision of simple mechanical drives for all auxiliary machinery.
Whether the locomotives were intended for Sri Lanka, Ghana, or in the later examples delivered to Gabon, the body was divided into three groups, carried on a conventional steel underframe. At the rear, a. short hood housed the batteries, followed by the cab, and a long hood over the power equipment, which itself was divided into three compartments. The compartment nearest the cab housing the electrical equipment, including the rectifiers, the next in line included the engine and generator/alternator assembly. Both of these compartments had a filtered air supply, whilst the third, at the front of the loco., housing the cooling group, radiator fan drives, etc., had no such luxury. The two two-axle bogies beneath the locomotive carried the d.c., series wound traction motors, hung from the axles, and with a spur gear final drive, in a fabricated steel frame, and main suspension of coil springs and hydraulic dampers. The fuel tank, as convention dictated was carried between the bogies.
The six metre gauge locomotives ordered for Ghana in 1983, had a 645 hp Rolls Royce engine, paired with the Brush generator, of the same basic design, but weighing 54 tonnes. The hood shape was slightly different too, being lower, and the cab roof had a much flatter profile. Turned out in a colourful red and gold livery, these six locomotives were worth some £2.5 million, and intended for trip freight working on the main lines.
Amongst the last major orders for diesel locomotives for main line service beyond the U.K., and for Brush, were 1100hp Bo-Bo’s for Gabon Railways (0CTRA) , constructed in 1985. These 90 tonne units were powered by Cummins diesel engines, coupled to a Brush alternator, for mixed traffic duties on the standard gauge. The three-phase output from the alternator was rectified to feed the four axle hung, nose suspended d.c. traction motors. Mechanically, the layout of the locomotives for Gabon was the same as previous orders .
GEC Traction’s involvement in new locomotive construction for overseas railways was largely limited to power equipment, or as subcontractors to others. Later examples of this in the 1980s was an order for 45 sets of electric transmission equipment for Krauss-Maffei built diesels for Turkey, with a Bo-Bo wheel arrangement a continuous rating of 940hp and weighing in at 68 tonnes. Another 5 locomotives for TCDD were to be supplied with 3-phase drives provided by Brown Boveri. The majority of locomotives were to be built, or rather put together in Turkey, as they were shipped out in completely knocked down. Most of these latter – 30 in all – had been shipped by mid-1986, although local assembly had not started until later that year and into 1987. Initially, after official handover, the Krauss-Maffei/GEC Traction locomotives were set to work on the Istanbul to Kapikule (On the Bulgarian border) line, and operated between Ismir and Ankara.
Refurbishing the electrical equipment of English Electric built diesel locomotives for East Africa and the Sudan and supplying engine spares also occupied the expertise of GEC Traction. The class 87 of Kenya railways is the equivalent of British Rail’s class 37, and extending its working life was a priority for its owners.
The Sudan became another overseas market for U.K. motive power when, in 1982, the Hunslet Engine Co., received an order for 11 0-8-0 locomotives for a 600mm rail line hauling cotton and cotton seeds from plantations to processing factories. Hunslet had been supplying locos. to the Sudan Gezira Board – the operators of this line – for almost 30 years, and the repeat order took the total supplied to the Sudan by Hunslet to 67 locomotives.
In the 1980s, the U.K. rail industry has undoubtedly been particularly successful in supplying main line electric locomotives, the winning of these contracts influenced by the wealth of experience and expertise of the contractors. Provision of power equipment, including alternators, generators, traction motors and control equipment also saw many more successes for the railway industry during this period, from Australia’s XPT to AMAX mine locomotives for the USA.
Multiple unit rolling stock for suburban and rapid transit systema around the world was another area where U.K. builders, again particularly GEC Traction and Brush, gained many valuable orders. A number of’ these contracts were secured in the far east, in locations like Singapore, Hong Kong, and Australia, where competition from the Japanese is especially fierce. Motive power orders though were predominantly concentrated in the field of electric traction, and the design and construction of locomotives for South Africa and New Zealand, were by some margin the stars of the 1980s.
20 years ago, and 2 years after the East Coast Main Line (ECML) was electrified from London to Edinburgh – only 10 years late – BR’s flagship locomotive “Electra”; also known as Class 91, saw service for the first time on the West Coast Main Line (WCML). To be fair it didn’t last long on the WCML, but in 1992, it set a fastest service record, with a train from London Euston to Manchester Piccadilly in 2hrs 8mins. At the time this loco was being developed, British Rail – and the InterCity Sector especially was making significant operating profits – and the completion, finally of the electrification work on the ECML was perhaps the icing on the cake.
The profitability of British Rail continued into the early 1990s, and in 1992/3, this press release was issued alongside the annual report:
In 1991, they put out this publicity brochure, to advertise what was coming:
Please click on the image opposite to read on >>
The “Electra” Project – the Class 91 – was one of the most innovative locomotives then developed for use on British Rail. In its Bo-Bo wheel arrangement it was able to generate some 4.54MW of power and haul 11-coach rakes of the new Mark IV coach when it became available. On the WCML it was planned to haul 750 tonne sleeper trains single handed, and the West Coast route, with the arduous ascents of Shap and Beattock between London and Glasgow, was much more demanding than the East Coast.
Thirty one Class 91 ‘Electra’ locomotives were ordered by BR, along with 50 of the Class 90 (formerly known as 87/2), and 86 sets of power equipment for the Class 319 multiple units. The locomotives featured the latest thyristor control systems, with more extensive use of microprocessors, and in a radical departure the separately excited (sep-ex), d.c. traction motors were included in the bogie space, but carried in the locomotive body.
The electrical equipment included oil cooled traction converters – featuring GTO thyristor components – and the main transformer was located below the body, between the bogies, lowering the centre of gravity, and assisting in the reduction of body roll, and relative pantograph movement.
The traction motors, as mentioned above, are body mounted, but slung below the floor, in the bogie space, which in turn, has enabled a more or less conventional layout of equipment on board. The transmission features a coupling arrangement patented by GEC Traction, with the motors driving the wheelsets through a right-angle gearbox, and bevel gears. The hollow output shaft of the gearbox drives the wheels through a rubber bushed link coupling, isolating the drive from relative radial and lateral movement of the wheelsets imparted by the primary suspension. Each traction motor was fitted with a ventilated disc brake at the inboard end.
The major characteristics of the Class 91 are detailed below;
Max service speed
Weight in working order
Unsprung mass per axle
Bogie pivot centres
Wheel diameter (new)
Max tractive effort
Cont tractive effort
Max power at rail
Brakes – locomotives
The class 91 order included an option for a further 25, and featured a double ended design, but with only the No.1 end having any degree of aerodynamic styling. In normal service, during the day, the streamlined end would normally be at the end of the train, pulling when running in one direction, and pushing, when running in the opposite direction. When pushing, control signals are transmitted to the Driving Van Trailer (DVT) attached to the opposite end of the train, by means of Time Division Multiplex (TDM) signals, sent along train wires, on board. The No.2 end cab is flat faced, and a profile that matched the profile of the adjoining coaches was adopted. The non-streamlined end would be used normally when the locomotives were running semi-fast, sleeper services, or other non high speed duties.
Interestingly, the class 91 was designed for a 35-year working life, averaging 420,000 km per year, which meant that in a couple of years’ time – 2023 – we would be saying goodbye to this impressive locomotive. But of course, events have turned out rather differently, and privatisation has created a much more complex operating environment, for both the technology of the train, and the management of the railway.
Sadly – although this year marks the 30th anniversary of its use on the WCML – they were never used in anger there, and by the turn of the century, the ‘Pendolino’ had arrived – by way of Fiat, Alstom and Metro-Cammell. There too, the technology developed at BR’s Derby Research Centre played its part in the late 1970s and into 1980, with the APT – but that’s a story for another day.
The Thompson era on the LNER was in sharp contrast to the previous twenty years, under the guiding hand of Sir Nigel Gresley. During Gresley’s day there were a number of notable designs, and the locomotive stock was represented by a large number of different types, often designed for specific purposes, produced in response to current business and commercial demands. Gresley’s designs could almost be described as bespoke, or niche products, aimed at satisfying an immediate business need, and not providing a standard range, or designing motive power which could be used on a wide variety of services.
The business of running a railway and providing commercial transport services had begun to change dramatically when Edward Thompson took charge, and of course, the demands of the Second World War denied Thompson the luxuries (in locomotive design terms) of the Gresley years. The business was demanding more efficient services, reducing costs – a recurring theme – and simplicity in the locomotive department.
After the initial trial running carried out under LNER ownership, when the design was new, the next major test for the B1s came in 1948, just after nationalisation, and the Interchange Trials began. Some interesting conclusions were drawn on the results of these trials, such as the fact that the B1 appeared to be more economical on the former Midland lines, and the Black Five fared better on the Great Central route!!
Later still, in 1951, a series of trials took place over the Carlisle to Settle route, and B1 Class 4-6-0 No. 61353 formed the subject of intensive trials between 1949 and 1951, along with static tests at the Rugby Test Plant. The B1 performed well, and overall, the tests seemed to indicate a good well-balanced design, with a free steaming boiler, and a locomotive that was economic and efficient at the tasks it was set.
In the end it was the arrival of BR Standard classes and diesel traction that signed the death knell for the class.