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New technology — or “High-Tech” — has many applications to modern railways. It is employed at all stages from design and manufacturing to running and maintenance. Probably the greatest hi-tech advance in the past decade has been in the field of electronics. And railways the world over have been quick to make use of advanced electronics in many applications. They include communications, signaling, automation and even traction control. Other advances in machine tools, materials, testing and research have all assisted railways to keep up with — and in many cases to better — their competitors.
DEVELOPMENTS IN THE UNITED STATES
As we shall see in the following sections, many of the high-tech developments in railways were pioneered in Europe. This has given the impression that the United States has not employed hi-tech to the same extent. But conditions in North America were different from those in Europe. Not only were all the railroads privately owned, but they were also unable to react to the effects of growing competition. American railroads were “common carriers” — i.e., they were unable, because of statutory regulation, to be selective and could not exploit one market at the expense of another. Passenger services were particularly hard hit by competition from the internal airlines and by private motoring, which enjoyed the benefit of extremely cheap fuel. No services could be withdrawn without the approval of the appropriate regulatory authority. The authorities were notoriously slow-moving and bureaucratic, but even so by 1968 American railroads were operating only around 500 long-haul passenger trains a day (compared to 15,000 per day in 1942).
The birth of Amtrak in 1971, a public corporation part-financed by the Federal administration (U.S. Govt.), did little to help. Its commercial freedom was limited, and many railroads found it just as difficult to make profits out of carrying freight. That and the refusal of administrations and unions to change time-worn operating and manning practices hampered any improvement in efficiency.
But progress has been made in the United States, although without the incentive of viable passenger traffic, development has not been so spectacular. In such a large country, the introduction of computers has benefited the railways. For example, what is now known as “TOPS” — Total Operations Processing System — had its origin on the Southern Pacific Railroad. In a system where wagons can so easily be “lost”, because of the vast distances they travel, the installation of computers to provide an immediate check on the availability, state of repair and deployment of all vehicles was invaluable.
American railroads were among the first to adopt electrification, but in many cases traffic did not produce a sufficient return on investment for wholesale modernization. An exception was the north-east corridor, where the lines of the former Pennsylvania and New York Central Railroads, later Penn Central, were kept reasonably up to date. Elsewhere, with cheap oil and highly standardized and relatively cheap locomotives, dieselization shows an immediate return on capital and electrification has been abandoned in favor of diesel. Other exceptions are urban transit systems and main lines with a high traffic density. The lines of the north-east corridor, particularly between New York and Washington DC, carry a relatively heavy (although subsidized) passenger traffic on a modernized line with, in places, speeds up to 200 km/h (125 mph). Politics have also played a major part in the fortunes of American railroads, probably even more so than in Europe.
THIRD WORLD RAILWAYS
Railways in the developing countries look at what is happening in the Western World. There are several countries with fairly advanced electrification systems, e.g. South Africa, India, China, Pakistan and Zimbabwe. In most of them their hi-tech equipment originates in Europe or Japan. Much of the Third World is still operating first- generation diesel locomotives, with fairly simple mechanical technology. Some countries are now building their own locomotives and rolling stock, and this trend will no doubt increase as the countries themselves develop. Computerization of control and signaling systems is now being introduced, but has to remain for the time being in the hands of foreign specialists until enough local people have been trained to operate them.
ORIGINS OF RAILWAYS
Let us have a brief look at how it all began. The first public train, from Liverpool to Manchester in 1830, was an example of early 19th-century high technology. George Stephenson had developed a boiler for his steam locomotive Rocket, which was revolutionary in that it embodied a number of small tubes running through it. These provided a large heating surface for the hot gases that passed through them from the firebox to boil the water in the boiler. The tubes were a considerable improvement over the one or two large diameter flues that were previously used. Moreover, after doing work in the cylinders, the steam was not merely exhausted into the atmosphere. It was led instead into the base of the chimney and, by means of a suitably shaped nozzle, was used to increase the draft on the fire in the firebox. This, in turn, helped to match the production of steam to the demand, within the limit of the size of the fire grate. This principle has been used in steam locomotives, with very few exceptions, ever since.
Technology in the railway industry kept pace with other developments and, with the need for ever shorter journey times, speeds increased and even newer technology was brought in to play. Signaling and braking are notable examples, both being necessary in the interests of safety. As signaling developed and, with the invention of the telegraph, embraced telecommunication, degrees of automation were introduced. Signal engineering became a highly technical business. To meet the need for a high degree of safety, automatic brakes, which failed safe, became a must.
ELECTRIC AND DIESEL TECHNOLOGY
While steam locomotive engineering remained relatively “low-tech”, the introduction of electric traction in the early years of the 20th century brought a newer and, for the period, higher technology to the scene. The development of the internal combustion engine into a reliable prime mover also saw another technology introduced into rail traction. In the first two decades of this century several experiments were made with both petrol and oil engines powering locomotives and railcars. Some of these were successful, others disastrous.
Electrical technology offered a number of potential advantages, not least of which was the possibility of pulling heavier loads at much higher speeds. Unlike a steam locomotive, an electric locomotive does not have to carry its fuel with it. It has access to relatively unlimited power from sources remote from the train by means of electrical conductors. High-speed trials with electric traction were made in Germany in 1903 on a 23.3 km (14 1/2 mile) stretch of military railway between Marienfelde and Zossen near Berlin. Two electric railcars reached speeds of around 210 km/h (130 mph), but not without coming dangerously close to derailment in one case because of the limitations of the track and the vehicles themselves.
The potential of electric traction is also attractive in countries where coal is expensive to produce or has to be imported. There is a particular attraction in mountainous countries where electricity can be generated cheaply by means of water power and used to drive the powerful locomotives needed to move heavy trains at reasonable speeds on steep gradients. Lines in the mountainous countries of Europe and the United States are examples of early electric traction schemes used to advantage.
The other major challenge to steam traction did not really materialize until the late 1930s. The early examples of petrol- and diesel-electric railcars in Sweden, Germany and Switzerland pointed the way, but it was in the United States that the internal combustion compression-ignition (diesel) engine really found its mark. With coal available relatively cheaply only in the eastern and southern states, oil was used to fuel some of the larger steam locomotives. But large quantities of water had to be carried when negotiating near-desert terrain. Also the low thermal efficiency of the steam locomotive encouraged the development of diesel locomotives and self-propelled passenger units, in which a given amount of oil consumed produced nearly three times the amount of work. By the late 1940s, there was a real need for a more flexible alternative to the very large and special-purpose steam locomotives required to haul long and heavy freight trains at reasonable speeds, particularly over the long grades of the mountainous regions. That requirement was comfortably met by modestly powered diesel-electric loco motives, which were run in sets of three, four or more under the control of one crew. Moreover additional “helper” locomotives could be spliced into trains at almost any point or at the rear, and so ease the strain on the drawbar of the leading vehicle. Later these helper units were to be remotely controlled by radio from the leading units.
It is since the demise of steam traction that really hi-tech systems have been applied to railways. Faced with ever- growing competition from road and air, railways have had to attract their customers by offering something not offered by alternative modes of transport. Most important of these have been cleanliness and comfort, with competitive transit times between city centers. This, in turn, involves very high-speed running on both existing and new tracks. It has also meant installing more power and the development of better permanent way, signaling and train-control systems, and greater refinement of vehicle dynamics.
It was competition from the electric tramcar (street car) that prompted the electrification of urban and sub urban lines in the early part of this century around large centers of population in Europe and the United States. A multiplicity of different systems emerged, and some of those have subsequently disappeared. Electrification offers much more than most other traction systems, and this is where the major applications of advanced technology are found today. In the rapid transit field, the trend is being reversed and tramways, having been displaced in many places by buses and cars, are now having a revival in the form of so-called Light Rapid Transit systems. Many of these employ high technology; some even entirely new technology.
So far, very high-speed passenger trains run on conventional tracks and in most cases have conventional suspensions — albeit mainly on new railway lines. For the future it is likely we shall see active suspensions — the tilt mechanism of the ill-fated APT (Advanced Passenger Train) on British Rail was an example of an active suspension; the current Italian system is also active. And by using micro-processors, the detection and control problems are very much reduced.
Electric traction has a great future, and we are at last beginning to see the maintenance man’s dream — the almost maintenance-free traction motor. In technical terms it is a three-phase squirrel-cage ac motor, which brings with it the bonus of regenerative braking. With state-of- the-art electronics (the missing link 80 years ago), it is possible to convert direct to alternating current, and to transform a single-phase ac fixed-frequency supply into three-phase variable frequency. There are a number of such types in service already, and valuable experience is being gained in locomotives and self-propelled (multiple- unit) trains on both sides of the Atlantic.
Other guided transport systems will undoubtedly be developed. The most promising so far seems to be Maglev — magnetically-levitated vehicles that “hover” over special tracks. One low-speed system has been operating in Britain for seven years between Birmingham Airport and Birmingham International railway station. Experiments with very high speed Maglev systems are being conducted in Japan and Germany, and much investigatory work has also been done at Pueblo in the United States. So far no one system has been shown to be ahead of its rivals, and all have to perfect methods which give complete integrity of levitation and braking.
It is not only traction systems that are forging ahead. Signaling and telecommunication engineers now have sophisticated train control and train protection systems at their command. High-speed lines like the Japanese Shinkansen, French TGV and German NBS (Neubaustrecke) would not be possible without automatic train protection (ATP). On new lines conventional visual signaling is no longer necessary or desirable, and all of the information needed by the driver can be provided in the form of a visual display in the cab. Train speeds can be regulated without the intervention of the driver and, in an emergency, immediate action can be taken automatically.
The civil and permanent way engineers have not been idle either. Track switches, or points, have been developed for very high speeds. New track-laying and repair techniques are being developed which do away with the lengthy periods of restricted running previously necessary, and, with the aid also of automatic train protection, delays can be cut to a minimum. Much more is known today of the interaction between vehicles and the track, and with the help of track-testing vehicles the state of the permanent way can be analyzed frequently and with greater efficiency.
What of the vehicles themselves? Passenger safety is rightly of great concern to vehicle designers. Today much more is known of the behavior of vehicle structures, while suspensions ensure a smooth and safe ride at all times. Air suspensions are now commonplace, and active suspensions are being introduced. The possibility of combining the two is very attractive.
Freight vehicles are also being transformed and the introduction of inter-modal vehicles, particularly in North America and Australia, is of immense importance.This is a particularly interesting time for students of rail ways and many technical developments are taking place. The following sections give an insight into the key innovations of recent years.