How Intercity Railways Learned from Metros: Part 4

It Started with a Dream

In America, on 26 July 1897, for one 10 year-old boy a dream came true. He got a brand new train set to play with. This was unusual in those days, since toy trains were rare and expensive but this was no toy. This was a full size train. He was given the controls of the first 6-car multiple-unit electric train to be put together at the General Electric Company’s works in Schenectady, New York and he was allowed to drive the train along the test track in front of the assembled officers and engineers of the Chicago South Side Elevated Railway. 

The boy’s name was Desmond Sprague and he was the son of Frank Sprague, who we saw in Part 3 introduced the first successful electric streetcar system in Richmond, Virginia in 1888. Desmond was showing off his electrical engineer father’s new system of multiple unit control, which Dad was trying to sell to the Chicago South Side Elevated. Well, sell it he did. The demonstration was a resounding success (“Hey, it’s so simple, even a kid can drive the  train”) and, within twelve months of this demonstration, the whole of the Chicago South Side Elevated system had been converted from steam to electric traction with 120 multiple unit cars (Figure 6). Oh that we could do things like this in such a short time today.

Figure 6: one of the Chicago South Side Elevated Railroad electric cars on test in 1898. This was a multiple unit car operating singly. Other cars were attached as required to make up trains.  Sprague himself can be seen second from the left standing behind the motorman. As was standard for many years, American driving positions were in a little cubicle in one corner of the end platform. The rest of the riders were company officials and other assorted hangers on.

Multiple Units

The principle of the multiple unit train was simple. A train could be made up of any number of cars. Each car was equipped with two or more motors mounted on the axles and, like a street car, a controller was provided on each vehicle for the 'motorman'. Additionally, a multi-core cable was was strung along the train and connected to these controllers so that they would all operate under the control of the motorman on the front of the leading vehicle. With this arrangement the train was operating "in multiple".

The arrangement allowed trains of varying lengths to have equal power and turnrounds at terminals were simple. The crew just had to change ends. Trains could be lengthened or shortened during the day by cutting or adding cars as necessary. The idea was an immediate success and quickly spread to other systems, first arriving in London in 1901 on the Central London Railway, now the Central Line of the Underground system.

In later versions of this system, not all trains were made up of motor cars (Figure 7). Some unpowered trailers were sandwiched between motor cars and various combinations were made up but the principal of the remote control of cars from one position remained the same. 

Figure 7: A diagram of a terminal on an urban metro syste (Central London Railway) showing the arrangement of multiple unit traction. It shows a six car train with a motor car at each end containing the traction equipment and driving cab. Because of the small size of the London tube blinds, the early trains built for the system had some of their equipment above the floor. Normally, multiple unit trains built to the original Sprague concept had all the equipment below the floor or under the seats.

Sprague’s conversion of the Chicago South Side Elevated Railroad to electric traction was not without its troubles. During the early months of 1898, while the newly converted trains were being delivered and tested, one of the cars caught fire. It was quickly found that the cause was electrical and that a large batch of the resistor grids were defective. Seventeen of the 20 cars by then delivered had to be taken out of service that day. Suffice to say, teething troubles with new rolling stock are not unique to modern times.

Main Line Reaction

Although urban railway systems quickly adopted multiple unit electric trains, mainline railways were slow to react. This was understandable. Electrification was (and still is) expensive and mainline railways would have to do it over long distances and they would have to convert large fleets of trains. They were already invested deeply in steam locomotive technology and conversion didn't make commercial sense unless the railway was very densely used. Even the improved terminal operations of electric railways weren't enough to convince most mainline railways to get into wholesale electrification.

In Part 5, we look at how it took until the late 20th century for main line railways to fully realise the benefits of metro operational techniques.

How Intercity Railways Learned from Metros: Part 3

Electric Traction

The development of electric traction for railways started seriously in the 1880s. Before this time, it was confined to a range of experimental schemes that were largely unsuccessful. The driver behind the development of electricity as a prime mover for rail vehicles was the need to improve urban systems, specifically streetcar or tramway operations. These were using horses. Horses were (are) expensive to keep, you needed three pairs a day for each vehicle you operated and they produced a lot of waste. In London alone, over 400 tons of manure was produced each day by horses in the late 19th century and it all had to be collected and disposed of. 

However, electrifying the horse-drawn tramways was expensive. You had to build your own power station because there was no national grid in those days, you had to provide a system of supply along the line, usually an overhead wire and you needed to buy new vehicles, complete with electric motors and the associated control equipment. But this expense could be justified if there were enough people using the system and, in the developing urban context, there were. Cities were expanding rapidly, suburbs were being built around them and people needed to get from them to their work and back each day. The urban railway had arrived. 

Figure 5: Richmond Union Passenger Railway Company showing off one of their original electric street cars introduced in 1888. The trolley pole on the roof of the car connected to an overhead line carrying the electrical supply to the the controller at the car end and thence to the motors under the floor. The return circuit was made through the running rails at zero volts. The driver or 'motorman' is at the right hand end and the conductor at the rear. Photo: Collection of: Frank J Sprague papers, OVERSIZE PHOTOGRAPHS. Image ID: 5665668

Electric Streetcars

The first successful electric tramway was opened in Richmond, Virginia in 1888. The engineer was Frank J. Sprague, a former US naval officer who believed in the future of electricity as a means of powering railways. His Richmond streetcar (Figure 5) carried 40 passengers and a crew of two. Controls were provided at both ends of the car so that, at the terminals, to change direction, the crew merely swapped ends. 

As urban tramways spread across the US and were introduced into Europe and other big cities around the world, increased patronage drove moves to increase capacity by lengthening a single street car into a train. The leading car was powered but it could drag additional, unpowered cars behind it.  But (isn't there always a 'but'?), with this, the terminal problem of the trapped motive power returned and powered cars had to be exchanged at terminals in the same way as the locomotives we saw in Part 2 of this series. Some lines had loops built to avoid the terminal swapping.

Then, in 1897 in America, our Mr. Sprague demonstrated an electric train using multiple unit control.  This trial was for one of Chicago's elevated railroads - a network of steam powered urban lines - and he was trying to persuade them to adopt electric traction. Part 4 of this series explains how it worked and what happed next.

How Intercity Railways Learned from Metros: Part 2

Developing Turnrounds

As terminal operations developed over the years, the methods for turning round trains improved. It became common at the larger terminals to provide locomotive sidings at the departure end of the station (Figure 4).

Figure 4: Terminal operation using two locomotives for a quick turnround. The arriving train has its locomotive trapped at the inner end of the platform track. The locomotive is uncoupled from the train and then waits for its removal. At the same time, the departure locomotive is moved from a loco siding at the departure end of the platform onto the train. It is then coupled to the train to make ready to take it away. Once the train has left, the arriving locomotive will move up the platform into the loco siding, where it will become the departure locomotive for the next train.

The process of using two locomotives in this way allowed rapid locomotive changeover and platform clearance, particularly important for busy terminal stations. And, it was made much easier when steam was eliminated and the locomotives became diesel or electric. Now, platform clearance times were largely regulated by the ability to unload and reload trains quickly.

The next development we look at is in Part 3 and it covers the adoption of electric traction and multiple-unit control.

Great British Cuts

UK Railway Finance

It is instructive to see that the newly appointed chairman of Great British Railways, Sir John Kingman, is a former Treasury mandarin. This does not bode well for railway support. This is a clear signal that the government sees the railways as too expensive and ripe for cuts in financial support. Sir John is sharpening his axe as we speak.

Few of the passengers who ride the trains every day think about how much the government has to spend on keeping the railways going. All they think about is the cost of the fare. They think that fares are too expensive and that they'd be better off using the car. However, despite the cost of fares, every year the British government spends about £12 billion on keeping the UK Railway system going. This is more than half of the total railway income of £25.9 billion.

Right: A UK railway finance chart as provided by the British government showing the totals of expenditure for the period of 2024 to 2025, the latest figures available. Information from UK Office of Rail and Road (ORR).

 

Cuts

Of course, the railways haven't helped themselves. Network Rail, the UK railway infrastructure manager, didn't manage to spend all the money that they've been provided by the government in the last financial 'control' period. They under spent it by 12%. They are also very big, very slow and very expensive. They are generally just like any other government department. 

I was once told that any time you ask anyone in Network Rail a question, the first answer is always 'No'. That needs to change. Management needs to be sharper, leaner and more responsive. Project management and contractor management night be the first places to look, Sir John.

The Future

Whatever this government decides to do in the short term, what the railway really needs is a long-term cross party approach. Railway assets invariably last from 20 to 60 years so their management and renewal programmes need to match this. The only way to do this is to have a long-term plan for renewals, replacements and upgrades. The plan needs to be agreed by all the government parties and it should be stitched into the UK's railway financing plans for at least a 40 year period. This would require a huge change in attitude but it really is essential to replace the existing feast and famine process that makes the railway so expensive.

How Intercity Railways Learned from Metros: Part 1

A Shift

Over the last 60 or more years there has been a system shift in the way railways operate, certainly in Europe at least. The shift has come in the way passenger trains operate - instead of locomotives hauling coaches, the coaches drive themselves. Instead of the traction power being contained in a single (or occasionally two) locomotives at the head of the train, the locomotive has gone and the traction system it carried in now distributed along the train, usually tucked underneath the passenger accommodation. There are a number of reasons for this and here we discuss the path from power on the front to power underneath and how it came about. We also look at some variations on the theme.

The Traditional Train 

We begin began with the traditional train. The traditional train comprises a collection of coaches (or freight wagons) with suitable motive power attached in the form of a locomotive. 

Figure 1: A steam locomotive hauling a train of passenger coaches. Photo: The Swanage Railway.

The train is made up of sufficient vehicles to carry the traffic offering and provided with enough power for the job. For passenger operations, one locomotive is usually sufficient. In heavy freight operations, this number might go up to four locomotives on the front and even some at other places along the train. 

A good deal of flexibility is possible with locomotive haulage. As long as the train weight remains within the capacity of the locomotive(s), any number of vehicles can be attached, although there will be limits imposed by platform or siding lengths. Locomotives themselves can also be flexible, many being designed to cover a range of duties. The advantages for locomotive hauled trains mean they are the best option for many railway operators around the world, particularly for freight carriers and for passenger trains where traffic is variable and train lengths need to be variable to suit.  However, this system has its limitations, particularly at terminals.

Terminal Operation

When a train arrives at the end of the line, it reaches a dead end. The locomotive stops at the buffer stops with its train behind it. It has nowhere else to go and, in fact, it is trapped by its train (Figure 2)

Figure 2: A diagram of a locomotive-hauled train in a terminal platform. The locomotive is trapped by the train, so another locomotive will be required to move the train and thus release the locomotive. 

To get out of this problem, another locomotive is needed to remove the train, usually by using it to form another service going back along the line. For long distance trains, it was the custom to remove the train to a siding where it was cleaned and prepared for another duty later in the day. Once the train had been removed, the locomotive could be released and it too would be taken somewhere nearby to be toped up with water and fuel and it you were lucky, it would get cleaned too.

A Single Loco Turnround

It is possible to use the same locomotive for the departure of the train rather than getting a second one for the job. It did require the provision of crossovers at each end of the terminal roads and it did mean that the adjacent track had to be kept clear of trains (Figure 3).

Figure 3: A diagram of a locomotive-hauled train in a terminal showing how the locomotive arriving with the train can be uncoupled from the train, moved forward over a crossover and then run along the adjacent track to the other end of the train. Here it uses another crossover to rejoin the train and made ready to take the train out on another trip.

The use of a single locomotive will not reduce the turnround time very much, if at all, but it does reduce the reliance on a second locomotive. However, during the steam era, arriving locomotives often needed refuelling so the single loco option wasn't often used except in the more remote terminals where frequency was low and resources were limited. Today, it is a popular method of operation for heritage railways.

In Part 2 of this series on how the railways learned from Metros , we will look at how terminal operation developed.

The Underground is Closed

The persistent closing of large parts of the London Underground (Tube) system at weekends must stop. The chaos, confusion and overcrowding it causes on the odd routes that are open has to be experienced to see how bad it is. 

I first wrote about this in 2011 and here we are, 15 years later and nothing has changed. In fact, it's got worse. The Piccadilly Line regularly gets shut down all weekend to do new train testing. One might wonder why they can't do it at night and one might ask why it takes so long. Are they so afraid of their engineering that they really don't trust it without years of closures to try it out?

London Underground 2024 Tube Stock being tested on the Piccadilly Line at Turnham Green one Sunday during the summer of 2026. Although the station is in use for the District Line, the platforms on the Piccadilly side have been taped off to prevent public access. Photo: Fortek67.

Actually, it's not their engineering, it's the suppliers' engineering. Since the trains were designed in Germany. Transport for London's engineers have little idea of what's been done and whether it meets their strict London-centric standards. Gone are the days when the Underground's engineers designed their own trains, using their long experience of operations in London, ensuring that it would work pretty much out of the box and getting it into service within a few weeks of delivery.

I feel sorry for the tourists who will go home saying, "Don't visit London, the Tube never works at weekends." I feel sorry for the staff who have to answer repeated questions on alternative routes. I feel sorry about the loss of income for shops and businesses.

Whatever happened to the "customer led railway" we hear so much about? We seem to have reverted to the old "operator led railway"

There must be a better way of managing the railway's renewal programme.

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Are standards for the railway too rigid?

Maybe. A case study on door operation.

Sometimes, it is worthwhile to re-examine your standards. Is your use of standards too rigid? Are you locking yourself into over engineering your railway? Are you sticking to the rules because they are the rules? Are there opportunities to gain time, reduce costs, improve visual impact or upgrade the passenger experience by adjusting standards, re-analysing risk or getting a derogation? This article offers a small but important example of how a standard could be modified to good effect.

This case study, first written in 2018 expressing concern about the rigid use of standards, is on train door operation. If we assume door opening is activated by a member of the train crew, we would want to ensure that the doors remain closed until the train has stopped. Once wheel stop (zero speed confirmed) has been detected, the on-board system can unlock the door opening controller and the crew member can release or open the doors.

Waiting for Doors

Fine? Yes, as far as it goes. It is definitely safe but this arrangement causes a considerable lag between wheel stop and door opening. Time is needed for wheel stop to be detected, for a release indication in the cab to appear, for the train crew to operate the release buttons, for the door controllers to receive the signal and for the doors to begin opening. On many main line trains, it can be 7-8 seconds before the doors are opened for passengers. On a metro or suburban service, it can be 3-4 seconds. An extra four seconds at every station on a line like the London Overground route between West Croydon and Highbury & Islington adds 76 seconds to the train’s journey time. This is half a train path and buying a peak-hour train path is expensive, so both time and money are being wasted. Perhaps there's a better approach? Perhaps we could use human experience to inform automated system protection?

In the days of guard door operation on the London Underground (finally abolished in 2000), there was no interlocking of doors with train movement. Doors could be opened while the train was moving. They weren’t of course (usually) but the facility was used to speed up station operation. The experienced guard knew that there was always going to be a lag between the train wheels stopping and the doors opening fully and he knew also that station stop time had to be kept to a minimum. To keep dwell time short, the guard would press the door open buttons a second or two before the train stopped so that the doors were beginning to open at wheel stop. Valuable seconds were saved and no one got hurt. So, why can't we replicate this in an automated system?

Speed Detection

Could human experience be replicated in automation? Of course it could. It fact, it already has. In January 1980, the first D Stock train went into service on the District line with a new door control system that kept the train door control locked while the train was moving but which allowed the guard to release the doors if train speed was detected below 4 mph. It replicated the human experience that allowed time to be saved at stations. It remained in use for many years but the idea was lost in the safety panic that ensued after the Kings Cross fire of 1987. Perhaps, now, with efficient train throughput at the top of the railway agenda, is the time to review the rigid zero speed restriction on door opening and make better use of the technology available for the digital railway. And, are there other examples where this approach could be beneficial?

Timetables and Control - Thameslink Case Study

Silence is Broken

Back in the Summer of 2018, I watched the continued disruption to the train services operated by Govia Thameslink Railway (GTR) with dismay and despair. I thought, after three weeks of operation following the introduction of a new timetable in May 2018, they would have got it sorted out, at least to a level where some sort of regular and reliable train service could be operated. But they haven’t. There we were, in the 6th week of the new timetable and there were still serious problems with the train service.

Why three weeks to get it sorted? Because, if you consider the average 24-hour shift pattern of early, late and nights, spread over three weeks of operations, it should allow most of the core staff to get used to the new pattern of services, the new train crew duties and the new routes. But it hasn’t happened like that.

Silence

I’ve stayed silent for a while as I thought I couldn’t add anything useful to the huge range of complaints, blame, calls for the stripping of “franchises” and largely uninformed nonsense from the popular press and social media. In vain, I waited for some sensible comments asking some basic questions about how the service was planned and how it was controlled on a day by day basis but none came. I waited in vain for a proper analysis of the issues and solutions but there were none. So I’ve decided to break my silence and offer some basic ideas, based on my own experience of timetable preparation in various places around the world and of train service operations.

The Routes

The Thameslink routes are too complex. The old setup with a Bedford to Brighton main line with the Sutton loop tacked on was quite complex enough, without adding such destinations as Peterborough and Cambridge in the north and Orpington, Sevenoaks, Horsham, Rainham, Littlehampton and East Grinstead in the south. In the originally planned December 2019 timetable, they were going to add Kings Lynn and Ashford too. This would not work well.

Battery-Electric Trains

Why Battery Electric?

Why?  Decarbonisation of course. The advances in battery technology, driven by the automobile and computer industries are now showing real benefits for the railway business. Batteries for traction are now a reality and are gradually entering mainstream. They are offering a way of decarbonising railway operations by replacing diesel traction with battery traction. 

Unlike a conventional electric train, a battery-electric train can operate without a continuous overhead wire or electrified third rail. It can replace a conventional diesel train, on a route without electrification. Full electrification is very expensive. It can cost up to £2 million per track kilometre. Being able to use a train with a battery offers the opportunity to decarbonise the railway without the expense overhead electrification. Battery electric trains need a rapid charging system but this can be provided at a terminus so the train can recharge while it's waiting for its next trip.

A diagram of the trial on the Great Western Railway using a former London Underground D Stock train as a battery electric multiple unit (BEMU). The recharging system uses track mounted rails to recharge the train rather than an overhead supply. Photo: GWR.

A feature of modern traction systems is that a train equipped with electric motors can use these for braking. During braking, the motor becomes a generator and the current produced can be fed back into the overhead line system on an electrified line or back into an on-board battery, if the vehicle has one. This 'regeneration' can be used to recharge the battery while the train is in service.

Challenges

However, the system is not without its challenges. After a long period of gestation, battery-electric trains are now being more widely recognised as a way to decarbonise the railway at a reasonable cost. We can define a battery-electric train as a railway vehicle that stores traction energy in rechargeable batteries and uses it to power electric traction motors.

The engineering challenge is to integrate energy storage, traction, braking, thermal management, structural design and system safety into a vehicle that can carry its own rechargeable batteries, recharge them en route and complete its journey on a finite battery charge. It also has to provide a viable and safe system of battery recharging and the electrical supply system to operate it. None of this will be easy.

Stadler 3-car Battery-Electric Multiple Unit (BEMU) Photo: Stadler.

In general terms, the engineering challenge is to ensure that the train has sufficient energy, power, range, acceleration and braking capability while remaining safe, reliable, maintainable and economical throughout its service life. For BEMUs, the jury is still out. They haven't been around long enough to see a whole life. However, the signs are promising with every increasing improvements in battery life and recharge ability.

Progress

BEMU trains first appeared in passenger service in Germany in 2020. They arrived after a long gestation period, but they pointed the way ahead. In the UK in February 2015, a battery-fitted Class 379 Electrostar unit began in trials on the Harwich branch. This was the first battery-powered train in the UK. It ran on battery power up to 77 kms. 

Some serious experiments began with the conversion of some former London Underground district line trains, known as D stock and now designated Class 230, that were converted for battery operation. Although a few are in use around the country, the conversion is expensive and the reliability is poor. Conversion of old equipment is always difficult. New builds have proved to be better.

The first purpose-built battery powered passenger train entered service on the extension from Kirkby to Headbolt Lane on 7 October 2023. More recently, Rail Operations Group’s Class 93 locomotives feat Scotture a battery pack as well as diesel power and 25kV overhead line operation and Hitachi tested a tri-mode conversion of a TransPennine Express Inter-City unit train with a battery pack in place of a diesel generator on one car. A fleet of 29 new BEMUs have been ordered for the Trans-Pennine route as a result.

TransPennine Express have ordered 29 new BEMU trains from Alstom. They will be built at the Litchurch Lane Works in Derby, They aren't expected to enter service until 2034. Photo: TPU

In London, the new 2024 Stock Piccadilly line trains (currently in pre-service testing) have a battery ‘get to the next station’ facility. In Birmingham, some of the CAF trams have batteries added to allow them to serve an extension of the system to Edgbaston Village. All of these are hybrid trains or trams and we can be sure that there will be more to come.

More information:

Battery electric and battery hybrid trains, Rail Engineer, June 2024.

Batteries Included, Rail Engineer August 2025