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By BRYAN MAHER THE EVOLUTION OF ELECTRIC RAILWAYS During dieselisation, US railroading swung away from the greatest steam locomotives ever built to large numbers of small diesel locos which were used in multiples. But they also built some monster diesel electrics and even experimented with gas turbine electrics. The world's first oil engine locomotive ran in England in 1894. Made by Priestman Bros. of Hull, this 9kW (12hp} four wheel powered truck could pull a few wagons but did not cause many ripples in the railway world at the time. Its mechanical .transmission was too difficult to control. · 80 From 1896 onwards Richard Hornsby of Lincoln, England (later Ruston-Hornsby) produced more than 20,000 "oil" engines, a few of which were used to drive railway vehicles in the early period. It remained for the Mallesta and Sodermanlands Railway of Sweden to show the world in 1913 how it should be done. Theirs was the first true diesel electric locomotive to be regularly used for passenger transport. It employed a diesel engine and DC generator combination mounted in a four wheel coach. One driven axle was powered by an axle-hung DC series motor in the modern manner. The diesel engine was of Atlas design, built with all the electrics by two Swedish companies which formed Allmanna Svenska Aktiebogola t, today known as ASEA. Some critics regard their larger 1917 model as the first diesel electric which could truly be called a "locomotive". To the USA Despite this successful start by Sweden, when it came to the race to build the biggest and most powerful PT.15 MASSIVE DIESEL ELECTRICS IN THE USA . SILICON CHIP ABOVE: HERE TWO GENERAL ELECTRIC U-50 class diesel electrics are coupled back to back to haul a heavy freight train over the Rocky Mountains. The U-50s had two V16 diesel motors giving a total power of 3.73 megawatts (5000hp). Note that each loco has four 2-axle bogies. The photo on the facing page shows one the huge 3.4MW (4500hp) gas turbine locos built by General Electric for the Union Pacific Railroad. The Union Pacific operated 40 of these giants during the 1960s while no other railroad ever got beyond one or two trial machines. diesel electric locomotives the scene shifted to the United States. And the Americans have since led most of the world, by building on the original Swedish design. Not that the US railroads wanted big for big's sake - rather their drive was (and still is) the sheer necessity for a private company to prosper and slay in business. Unlike those of our country, US railroads live in a world of fierce competition. Only the best, most efficient, most economical (in dollars per tonne-kilometre moved) can survive. Today in the USA, with essentially all passenger traffic gone to Amtrak (the US Government-owned passenger line), airlines, buses or private cars, the fight between private railroads is for the freight business. To satisfy the customers, the railroad must regularly run fast freight trains at up to 145km/h. To keep running costs down, large diesel electric locomotives must haul freight trains three or four kilometres long, weighing 5000 to 20,000 tonnes or more, even in Rocky Mountain country. So American railroads made a very rapid transition from steam locos to diesel, as noted in our last episode. And the rest of the world followed suit, largely because they had to. The big three American steam locomotive manufacturers Baldwin, The American Locomotive Company (Alco) and Lima - all had trouble seeing the diesel .electric trend coming. Then all found that tradition means little in competitive business. Three newcomers to the loco building business had appeared upon the American scene. Steam's last day Though spring was officially blending into summer, the drizzling rain had made the day more like autumn. Apart from that, April 4th, 1960 was much the same as any other day and four young American boys could not be expected to realize that transportation history was being made right there and then. Perched on the back fence in their customary train-watching posture, like crows on a clothes line, they could hear the roaring bark of yet another beloved giant steam locomotive. Huge 550-tonne Mallet 2-8-8-2s and faster 2-6-6-2s had been hauling unit coal trains and fast freighters past their suburb since forever, or so it seemed. Their families lived not far from Roanoke, Virginia, right beside the right-ofway of the mighty Norfolk and Western Railway. Lately some diesel electric locomotives had been added to the fleet but these had to be coupled in multiple. In many places the boys had seen locos like the early EMD Co-Co diesel electric model E8A. These were quite heavy at 152 tonnes, yet not very strong with a mere 11 tonnes (25,000lbs) drawbar pull, despite using a big 1.64MW (2200hp) diesel engine. It required six of these diesel electrics to pull the heavy N&W coal trains up the mountains, a task previously performed by a single large steamer like the early 2-10-10-2 Virginian 800 class or the older 2-8-8-8-4 700 class. The 700 class drawbar pull was a fantastic 76 tonnes (168,000lbs). This, the most powerful steamer ever built, could singlehandedly pull a 7100 tonne coal train up a 1 in 62 mountain grade. Wow! Those young boys could not have known that the Norfolk & Western company had retained the services of these giant steam locos a decade or more longer than other US railroads. The reason was simple - the steamers were the best and most economical solution. Sure, some of those youngsters had, while holidaying in other areas, observed with astonishment strings of diesel electric locomotives multiple-heading long freights. One lad had once been amazed to see a long freight hauled by no less than 10 diesel electric locos, all controlled by one engineer at the front. The nation's young citizens couldn't yet appreciate the running battle waged by salesmen from General Motors' Electro Motive Division against Norfolk and Western's steam locos. In the 1940s and '50s, EMD's philosophy was to offer to all US railroads standard general purpose diesel electric locomotives of power rating around 1.1 to 1.6MW (1500 to 2200hp). JANUARY 1989 81 TIIE UNION PACIFIC RAILROAD'S "BIG BOY" was reputedly the most powerful steam locomotive ever built. This giant was the equivalent of two steam locomotives under one huge boiler and produced 4.5MW. EMD's concept was that it was cheaper to purchase standard diesel electric locomotives and couple as many as needed together to perform each haulage task. Other manufacturers would provide sets of two, three or four units more-orless permanently coupled together, all controlled from the head end, ·classed as a single loco of great power rating. The etymological inferences in classing four machines as "one locomotive" was above the kids' collective heads. Absorbed in their daily train watching, how thrilled the bcys were when the mighty Y6b class 2-8-8-2 rounded a bend and appeared in view. As it blasted its way up the heavy grade, part of the Appalachian mountain climb, the very ground shook with the reverberation of that monster steam locomotive. History was indeed being enacted before their eyes. Little did they know it but they were witness82 SILICON CHIP ing the final run of the last steam locomotive under full commercial load in the United States. Their customary enthusiastic waving to the engineer produced a rather sad response - the loco whistle seemed more like a banshee's wail. The giant Y6b class steamer, all 550 tonnes of her, finished that day's run with a 5000 tonne coal train in tow, then quietly drifted into the maintenance shop. Her fire was dropped into the ash pit and the locomotive allowed to go cold, to be demolished the following day and sold for scrap. And the Y6b class locos were no more than 8 years old! In practice, the Y6b class locos were just as efficient and less complex than the competing diesel electrics. They were scrapped only because it became impossible for the N & W to remain the only steam powered railroad in the USA. Though the Norfolk and Western had always built its own steam locomotives, all suppliers of vital components had ceased trading in such items. Enter the new loco makers Now the N & W railroad would have to purchase all diesel electric locomotives from amongst the three or four remaining loco manufacturers. The EMD plant at La Grange in suburban Chicago, Illinois could turn out enough diesel electric locos to supply all the USA and much of the world but they had competitors: Alco, Fairbanks-Morse and General Electric. The American Locomotive Company (Alco) at Schenectady, a steam locomotive manufacturer from way back, took on diesel electric production and even licensed manufacturers in other countries, to build to their designs. Despite (or because of?) their record total of 78,000 steam locomotives constructed over the years, Alco found the change to diesel electric production difficult. But the company persevered and produced many successful designs. In 1965 Alco dispatched to Australia five of the largest diesel electric locomotives ever exported from the US. These model C628 CoCo 2.05MW (2750hp) 176-tonne locomotives went into service at Hamersley Iron's iron ore railway in Western Australia. Three years later the A. E. Goodwin company of Australia built under licence even larger Alco locomotives. These were model C636 2.69MW (3600hp) machines for the three Western Australian iron ore mines: Mt. Newman, Robe River and Hamersley. Back in the US of A, some of those kids, when on holiday to other states, had once found themselves travelling in a train hauled by a Baldwin diesel electric locomotive of unusual design. Baldwin diesel electrics The Baldwin locomotive works, founded by Mathias Baldwin at Philadelphia in 1831, had prospered under steam locomotive production for over one hundred and twenty years. That company could be proud of many locomotive building records, including the first Mallet articulated locomotive. Baldwin's huge company plant, capable in 1940 of producing three THIS WAS THE DADDY OF ALL diesel electrics, the Union Pacific DD50 "Centennial". They were effectively two standard diesel electric locos on the one chassis. Rated at 4.92 megawatts (6600hp) these huge beasts weigh 247 tonnes and are almost 30 metres long. Note the huge fuel tank hanging underneath and the massive 8-wheel bogies. large steam locomotives per day, did not succeed in the race to the top in the diesel electric world. Traditionally they had custom built steam locos to the designs and requirements of each railroad. When the American Baldwin company did enter the diesel electric market, they continued to think big. In 1940 Baldwin engineers designed their prototype "Centipede" locomotive number 600, meant to contain eight 560kW (750hp) eight-cylinder diesel engines, each mounted across the loco body. Each diesel engine was to drive a DC generator, the whole loco thus to produce a total power of 4.5MW (6000hp). Engineering difficulties prevented all eight diesel engines being installed, so they ran with four, giving 2.25MW (3000hp). Mildly successful, 53 such locomotives were produced and sold to three US railroads. Sadly, today the Baldwin Locomotive Company is no longer in business. The General Electric Company, widely experienced in electric locomotive production since the 1920s, had less trouble in turning to diesel electric manufacture than did factories like Baldwin which had enormous investments in plant tailored to steamer production. Possibly that fact alone was enough to severely dent the fortunes of the Baldwin works but a worse mistake was their failure to see that railroads no longer needed single huge locomotives. Union Pacific "Big Boys" Union Pacific was and is one of America's most successful railroads, based in Wyoming. Wyoming is a mountain state, wherein the UP Railroad has for more than a century powered their trains over the Sherman Hill summit of the Rocky Mountains on the way to the west coast cities. From the marshalling yards of Cheyenne, long trains weighing up to 7000 tonnes would constantly stream up on the 104km (65 mile) climb to the peak of Sherman's Hill. They had always used giant steam locomotives. Their 2100 class engines had a 4-12-2 wheel arrangement which was almost unique in the world. Later came the articulated "Challenger" 4-6-6-4s and by 1941 JANUARY 1989 83 came the regular passing of the "Big Boys", reputedly the greatest and most powerful steam locomotives ever built. These 4-8-8-4s were a thing of beauty, power and grace, despite their enormous size. Made by Alco, these 4.5MW (6100hp) steam giants single-handedly hauled 5000 tonne trains over the Rockies. The loc0$Ilotive alone weighed 351 tonnes Imd the huge twelve wheel tender carried 30 tonnes of coal and 110 tonnes of water. The whole engine with tender fully loaded weighed close to 600 tonnes. They would eat up a full load of coal in 90 minutes flat on Sherman's Hill! That 135,400lbs (61.4 tonnes) tractive effort had to come from somewhere. No fireman could shovel coal that fast. Mostly his efforts would be expended inside that ship-like tender, trimming the coal as it slid towards the mechanical feed screw which force-fed the huge firebox. The fireman would have enjoyed the ride down the western slope. The double track Union Pacific line has been repeatedly straightened and graded, till now it carries a 145km/h speed rating for fast freights, all the 561km distance from Laramie down the long slope to Evanston (most of the width of Wyoming)! Gas turbine locos In 1949 the Union Pacific Railroad purchased from the General Electric Company something radically new - a 260-tonne gas turbine electric locomotive. Only a demo model, the men said, but the older steamer "engineers" looked at the new machine with suspicion and awe. "Can that crate full of airplane engine-cum-electric power house pull a train like our steamers?" No coal shovel was needed! But that "gas turbine crate" could exert a powerful pull on the drawbar, its 3.4MW (4500hp) driving through every one of its 16 wheels. The BoBo-Bo-Bo wheel arrangement was something quite new. Union Pacific bought fifteen of those gas turbine electrics in 1954, and often coupled two of them together, controlled by the one engineer at the head end. Such a combination proved about equal to a "Big Boy" in speed and pulling power. AS IF ONE CENTENNIAL was not enough, here are two DD50s coupled together to give a total of 9.84 megawatts or 13,200 horsepower. These were EMDs first locos to use alternators instead of generators and they used silicon rectifiers to produce the DC for the eight traction motors. 84 SILICON CHIP By 1959 a further order of gas turbine locomotives was delivered but this time GE made them as twounit locomotives by literally joining two machines together, giving a total of 6.34MW (8500hp). A twelve wheel fuel tank hauled behind catered for the heavy fuel consumption of the gas turbines. While the all up weight of the twin unit loco plus tender was comparable to that of the steam Big Boy, these GE gas turbine electric locomotives could certainly pull. They ·gave a total of 109 tonnes (240,000lbs) of tractive effort! The devlopment of gas turbine locos The General Electric Company had been into electric locomotive building from 1920, even before EMD began. GE had never been in the steam business so were not lulled into any false sense of future trends as the traditional steam loco niakers were. That fact, together with GE's worldwide financial power and diversity, accounts for GE being the only major competitor against EMD in today's world of diesel electric locomotive manufacture. But GE were not as committed to "off the shelf" locomotive selling as EMD. Consequently, when the Union Pacific Railroad wanted some exceptional locomotives designed and built, they went to GE to develop gas turbine locomotives from existing airplane engine technology. So successful were these GE gas turbine electric locomotives that the Union Pacific Railroad operated 40 of these giants during the 1960s, while no other railroad in the world ever got beyond one or two trial machines. The advantages of gas turbines lie in their high power to weight ratio but they guzzle fuel at an alarming rate. Gas turbines give their most efficient service when run at constant speed on full load for long periods. This suited the Union Pacific Railroad's long haul up the 1 in 122 grades approaching the 2515 metre peak of Sherman Summit on the Rocky mountains, running from the Cheyenne marshalling yards in Wyoming to Utah. Gas turbines are very inefficient in starting/stopping service, when idling or running on light load. Therefore GE included within the loco a 276kW (370hp) standard diesel engine and generator which supplied sufficient power for the downhill run. This had enough power to overcome rail friction, run the air compressors for the brakes, and supply the train control and headlights. It also provided traction motor field power for dynamic braking. The small diesel engine was also used to move the locomotive around marshalling yards. This meant that the big gas turbine did not have to be started for short runs. Due to the high noise level and high pitch sound of gas turbine engines, objections would have been raised if these locomotives had been used in heavily populated areas. However Union Pacific crosses the Rocky Mountains in sparsely populated areas, so few environmental objections arose. Due to the high turbine speed and the dry, high temperature ignition environment within a running gas turbine, these machines are more ANOTHER BIG POWER LOCO used by the Union Pacific was the C855 made by Alco. These are much bigger than any diesel loco even seen in Australia or anywhere else for that matter. They were rated at 4.1 megawatts (5500hp). susceptible to damage caused by dust in the air intake than are diesel engines. Therefore, great care was taken with intake air filtering in those locomotives. GE monster diesel electrics In 1964, General Electric continued its success by building a batch of 3.73MW (5000hp) diesel electric locomotives. These had an unusual Bo-Bo-Bo-Bo wheel arrangement (ie, four 2-wheel bogies) with all 16 wheels driven by eight DC series traction motors. Designated the U50 class, they employed two 16-cylinder diesel engines. Alco answered the challenge by producing three C855 class 4.1MW (5500hp) Bo-Bo-Bo-Bo diesel electrics for the same railroad. And this was not the last of Union Pacific's forays into big big power locos. EMD's novel design Breaking away, temporarily, from their general-purpose off-theshelf philosophy, the Electro Motive Division of General Motors designed a line of monster diesel electric locomotives for Union Pacific. These are unique in many respects. As the year was 1969, the hundredth anniversary of the completion of the UP line, this locomotive class was called " Centennial" . Each loco had two 16-cylinder V16 diesel engines, with a total rating of 4.92MW (6600hp). They employed huge 4-axle bogies with all wheels driven. Also a first for EMD was the use of alternators and silicon rectifiers to provide very large DC currents for the DC series traction motors. The complete locomotive weighed 247 tonnes. Today the Union Pacific operates a very successful railroad using 1400 diesel electric locomotives altogether, one of the largest fleets in the USA. But today's trend is away from the 5000 and 6000 horsepower monsters towards more modern and more economical designs. That's a story for a future episode. ~ JAN UA RY 1989 85