Passenger Train Variations

All the trains shown in the three pairs of pictures above were designed by the former British Railways and except perhaps for the liveries (paint / colour) when introduced into service were more or less identical nationwide (within the type of train). However, since railway privatisation the various train operating companies have repainted their variants in a range of different liveries and in some cases have also refurbished them so that they look different and / or feature different types of seating.

Nowadays virtually all British trains* feature power operated doors that are controlled by either a guard or driver. Even if the trains also feature passenger operated 'open' and 'close' buttons the train driver or guard will still (usually) have the ultimate control.

A specific problem often faced by trains with power operated doors is that rather than spread out evenly throughout the carriage many passengers congregate in the doorway, which at stations blocks access to the rest of the carriage and extends the time it takes passengers to board and alight (ie; the 'dwell' time). A solution which has been adopted on some trains is to redesign the entrance area inside the train to create a larger circulating space just inside the doorway. Sometimes this involves removing seats and making a space that is setback from the doors, other times it sees transverse seats replaced with longitudinal seating - which also makes more space for standing passengers.

In Australia urban rail services (where they exist) are operated regionally, based on the various State Capitals - Perth, Western Australia (WA); Melbourne, Victoria (Vic); Brisbane, Queensland (Qld); Sydney, New South Wales (NSW) which have electric urban systems and Adelaide, South Australia (SA) which for many only had diesel trains but by 2013 was converting some routes to electric traction. Melbourne, Adelaide and Sydney also have electric tram systems.

Queensland and New South Wales also have electrified regional / InterCity services, and especially in Sydney there is much overlap where some services which act as urban / suburban trains within the city then continue their journeys to serve nearby regional towns.

No Australian cities have true "urban transit" underground railway systems however in Sydney, Melbourne and Perth city centres some of their services have been located below ground where they operate as underground railways. In many ways this is a very similar arrangement to that which exists in the English city of Liverpool.

In New Zealand only two major cities have suburban networks. At present (2013) Auckland's network is wholly diesel operated and the fleet includes some heavily rebuilt / modernised trains of late 1960's vintage which originally operated in Perth, Australia, but were no longer needed when their suburban services were electrified, and some former British Railways carriages (see next paragraph). In addition to its electric trolleybuses many suburban lines serving Wellington are electrically operated. In 2012 Wellington's last British-built electric trains dating from the 1949-54 period were replaced by South Korean rolling stock. In recent years both cities have seen patronage of their urban railway systems increasing so much that overcrowding has become an issue - which to alleviate they have both been expanding their networks and increasing the size of their fleets.

In addition to suburban trains from Perth, Australia, between 1996 and 2006 some former British Railways InterCity Mk2 carriages dating from 1971-5 were imported into New Zealand and having been suitably modified are used on a range of services. These include suburban services in Auckland, for which they have been very heavily rebuilt with suburban style sliding doors and one end of some carriages were also fitted with drivers cabs, so that the trains can operate in 'push-pull' mode, being poweerd via a diesel engine which always remains at one end of the train. However with the routes they serve being electrified and a new fleet of electric multiple-units being delivered so in circa 2014/15 much of the former British rolling stock is expected to be withdrawn from front front-line services.

Because of the mountainous terrain it was decided that to reduce construction costs the railways will use 3ft 6in (1,067mm) Cape gauge, and as a result most lines also have a limited loading gauge. So whilst new trains (such as the Hungarian trains seen below) would have been built to be suitable any trains which have been imported from Australia and Britain have had to be modified to suit this narrower gauge.

Paris, France, has several marketing brands of urban / suburban railway services. These include "Transilien", which mostly involves trains that travel into mainline terminal stations around the centre of Paris, and the "RER" (regional express railway) which involves suburban trains that link up suburban railway routes on opposite sides of the city, mostly by means of new-build subterranean linking tunnels below the city centre.

Together these serve the wider built-up area plus close communities which form what is known as the Île-de-France region of France. This is in addition to the Parisian métro, which primarily serves the part of the entire Parisian conurbation that comprises the historic city of Paris.

Overseeing all transport operations and co-ordinating the different transport companies in the region is a body called STIF - Syndicat des transports d'Île-de-France.

The name Transilien is a variation on the word Francilien, this being a term that is frequently used to describe the inhabitants of the Île-de-France region of France.

To maximise passenger capacity the French Z50000 urban / suburban trains feature articulated short-length passenger carriages of just 16.53m / 54ft 3in [end carriage], 13.24m / 43ft 5in [most intermediate carriages] and 8.29m / 27ft 2.5in [central carriage on shorter trains only]. Being shorter means that they need a less wide swept path on curved track, so as a result at 3.06m / 10ft 0.5in they are appreciably wider than more traditionally dimensioned types of train and which typically have carriages that are circa 24m - 26m / 79ft - 86ft in length and 2.89m / 9ft 5.5in in width.

These trains come in two train lengths. Eight carriage trains seat 472 passengers, including 92 folding seats. The shorter seven carriage trains provide 380 seats, 74 of which are folding / tip-up seats. Thanks to the extra width of the train it is possible for some of these seats to be in 3 + 2 format and still maintain a central walkway between them that is 55cm / almost 22in in width. The seats are cantilever in design, which means that they only cling to the side walls, this creates space below them for luggage and also makes it easier for the cleaners to sweep the train's floor. As the images suggest, the seats are upholstered in a range of eight different colours, these being raspberry, gray, yellow, burgundy, orange, red, soft green and purple. The trains also feature blue coloured underseat lighting. This can be seen, reflected on the floor, in some of these images. As if that is not enough colour the ceiling lights in the areas between the doorways also vary the colours shown, with white being for when the doors are open, blue when the train is accelerating and orange when it is coasting or braking!

Normally when in passenger service two such trains are coupled together to form one longer multiple-unit train; although it is possible to couple-up three such trainsets, if required.

The two end carriages include space for passengers who use wheelchairs, pushchairs / buggies / strollers, etc., ie: personal wheeled transports. In addition elsewhere along the train is shared space for cycles, although this too requires the tip-up seats to be closed.

The trains feature large double-glazed windows which provide 50% more glass area than the trains they replace. In addition to the gain in brightness, passengers benefit from clear unobstructed views of the outside at eye level. As the trains are fully air-conditioned the windows cannot be opened. This both prevents loss of air conditioning efficiency and the throwing of objects out of the train.

In addition to real-time travel information displays these trains feature video screens which are located at carriage ends / one per each corner. These show the digital terrestrial television (DTT), cultural information, local weather; passengers must wear wireless headphones to listen.

The trains are capable of operating from overhead wires energised at either 1.5 kV DC or 25 kV AC and have a top speed of 140km/h / 87mph.

These trains have been designed for various platform heights.

All passengers benefit from level access at stations where the platforms are about 92cm above ground.

To make life easier for passengers who use personal wheeled transports the doors in the two end carriages feature gap-fillers which automatically deploy so as to plug the approximately 10cm gap between the train and platform.

When the trains call at stations with low height platforms (55cm or less) extending steps automatically deploy below all the train's doors.

The RER is jointly operated by both the mainline railway (SNCF) and the citywide urban transport company that also runs the métro, funicular, trams and buses (RATP). Sometimes services are provided by trains which are in "Transilien" livery.

In an effort to maximise passenger loadings the S-tog trains in the Danish capital (Copenhagen) which date from 1996 use these revolutionary short wheelbase articulated walk-through trains that when first introduced totally re-wrote the "rule book" on modern train design.

Short wheelbase single axle passenger carriages were known in the early days of the railways when passenger carriages emulated horse-drawn stagecoaches, but for various reasons fell out of favour when longer carriages with bogie wheelsets at each end became possible.

To facilitate the extra width of these trains they use very short carriages which on bends neither stick out so much at the ends nor have the middle of the carriage 'cut the corner' on the inside. To reduce the trains' weight and consequential power consumption they are articulated and use single axles (2 wheels) instead of 'bogie' units (which usually use twin axles / 4 wheels). Most trains are constructed as 2x4-carriage units permanently joined together. The outer carriage (with the driver's cab) has a wheelset at each end whilst the other carriages have one wheelset of their own and partially 'hang onto' the previous carriage. Despite using single wheels the ride quality is very acceptable.

For those who would like more detailed information on these Danish trains: The driving carriages are 12m (metres) in length and the trailers 10m. The fleet consists of 136 trains; 105 of which have 8 carriages (and are known as Litra SA) and 31 of which have 4 carriages (and are known as Litra SE). At just under 84m in length an 8 carriage train is comparable in length to a 4 carriage version of the older trains. Especially at busier times two units operate in multiple, giving 16 carriages in total. These new trains are 3.6m wide (the older trains were 3.0m wide) and at 312 (plus 28 folding seats) they seat about 33% more passengers than the older trains - without the need for expensive lengthening of station platforms! In total 8 of the 10 axles per 8 carriage new train are motored, giving them a maximum acceleration rate of 1.3m per second and top speed of 120km/h (about 75 mph), although signalling or track limitations means that this speed is only reached on some routes. They are powered at 1650v DC and feature regenerative braking, reducing the energy requirement from the power station by approximately 40%. The shorter 4 carriage trains are a little under 43m in length, they offer 134 fixed seats plus 16 folding seats,

Faced with rising traffic congestion the people of San Francisco USA did not want to emulate their southern Californian neighbours in Los Angeles who were trying (and failing) to solve traffic congestion through massive road building and after much discussion / campaigning the BART (Bay Area Rapid Transit) scheme developed. Opening in 1972 the system now boasts 44 stations over 104 route miles (approximately 167km) and includes a station serving San Francisco International Airport. Another feature is the Transbay Tube which runs under San Francisco Bay and is the longest underwater tube for an urban railway system anywhere globally. The tube itself is 3.6 miles (5.7 km) in length, although including the approaches from the nearest stations (one of which is underground) it totals 6 miles (9 km). At a maximum depth of 135' (41 m) below the surface it is also one of the deepest vehicular tubes known about in the public domain in service today. (Although the suggestions remain unsubstantiated it is possible / probable that the military have access to a 4000+mph [6400+km/h] maglev located approximately 4 miles [6.4km] below ground).

The BART system is electrified at 1000 volts dc with the trains using a third rail power collection system. For rapid acceleration every axle (wheelset) is motored - making four motors per carriage. The trains feature an aluminum body, carpeting, air conditioning, tinted windows and are a generous 10' 6" (3.20m) wide, with an impressive 6' 9" (2.06m) headroom - which is just as well, with so many local people being over 6' (2m) tall! The actual length of trains varies between 3 and 10 carriages depending on line and time of day. The maximum speed was originally 80 mph (130km/h) with the average speed including 20 second station stops being about 33 mph (53km/h). Since 1976 the usual speed limit has been 70mph (110km/h) because on a fully loaded car the single disc per axle braking system will fail when making an all-friction stop from the former top speed. According to the Wikipedia Encyclopædia this was known right from when the system opened and another disc on each axle was recommended, but BART believed such a failure of the non-vital dynamic brake system would be rare. However there have been some failures and when this happens it creates a safety hazard.

Being a brand new system which does not share infrastructure with any other rail operations it was decided to build the trains to a more generous specification than might otherwise have been possible and therefore the track gauge is 5' 6" (1.676m) compared to 4' 8" (1.435m) for standard railways / railroads; this would have been done because a wider track gauge is more suited to wider trains and usually provides a better quality of ride. Another possible reason for this wider track gauge is that it assures none of the private freight railways that BART will ever want to extend its services over their tracks, and prevents them from wanting running rights over tracks owned by BART.

BART operates five different sets of services which mostly interleave so that much of the system is served by trains on two or more routes. Four of these share the Transbay Tube and at busy times (especially the rush hours) significant congestion occurs as the multiple lines vie for shared resources. In the longer term a second tunnel is planned. This will feature four tracks - two for BART and two for other rail services - including the proposed California High Speed Rail system.

There is some debate as to whether BART is a subway/metro or a regional service. Some people suggest that its acts more like a regional commuter railway because whilst it links two cities (San Francisco and Oakland) with their hinterlands it was not designed to provide frequent local services. So whilst it is often thought of as a subway / metro the service it provides is more akin to London's Thameslink, the Paris (France) RER, the Berlin (Germany) S-Bahn (and others) except that it does not have to share its rights of way with other railway services.

(NB: ' means foot; " means inches; metric conversions are approximate).

Depending on the type of the carriage BART trains offer 64, 68 or 72 seats. At crush load each carriage can carry as many as 150 passengers (including standees).

The aerodynamic nose cone which extends 5' (1.5 m) in length has become an iconic distinctive feature of the system.

New trains are currently being designed, the first should be ready for testing in 2015 with full scale production in 2017.

Another form of 'short distance' trains are undergrounds, subways, métros and mini-métros.

These are generally 'city-specific' transit systems which are operated by a specialist urban transit authority which often also runs the street-based transport (buses, etc,.) too.

Most of these systems use traditional 'steel wheel' on 'steel track' technology however a few systems use trains that run on rubber tyres. This page makes no distinction

The principal difference between a métro and mini-métro is that the latter will be designed for routes with lower traffic flows and therefore will use shorter trains. In other respects they are both more akin to 'heavy' rail in nature with fixed infrastructure, tunnels, etc., costing roughly the same to build except that where shorter trains are used there will be some savings in the cost of constructing the smaller stations.

Sometimes métro and mini-métro trains will be able to negotiate sharper curves and steeper gradients than the other types of 'heavy rail' trains. As with the difference between 'light' rail (aka trams / streetcars) and 'heavy' rail the dividing line is indistinct - there are no fixed rules; instead the philosophy is that 'if it works / suits the location' then "fine".

The first underground railway "anywhere" globally was the Metropolitan Railway which opened in London in 1863.

Traditionally London Underground trains were painted red, however from the 1960's onwards all new trains featured aluminium sides that did not need painting to protect them against the weather. One small fleet of trains which date from the 1970's featured painted doors, this might have been to distinguish it from an earlier batch of similar rolling stock. One of the advantages of not painting the trains is that they then weigh less - and consume less energy. However, following problems in the 1990's with graffiti vandalism and a desire for a corporate image there was a rethink in policy and nowadays the trains painted red, white and blue. Even without the graffiti problem a change of policy would have been necessary. because nowadays disability legislation requires that train doors are painted in such a way as to easily discernable by people with limited vision.

Apart from London, Glasgow is the only other British city with a 'city specific' Underground railway.

After London and Budapest (not illustrated) Glasgow became the third city "anywhere" globally to open an urban underground railway system. Built by the Glasgow District Subway Company it 1896 it is in the form of a 6.5 mile (approx 10.4km) circle with trains travelling both clockwise and anticlockwise. Because of Glasgow's geology the subway had to be cut with great difficulty through solid rock; this accounts for both the small size of the tunnels and why the system remains the same size as when it was first opened. Between 1936 and 2003 this system was officially called the Glasgow Underground, but the name has now reverted back to Subway.

Between 1977 and 1980 services were suspended to allow for significant rebuilding / modernisation which included procuring brand new rolling stock and modification to the stations which amongst other things permitted longer trains. When the system reopened it was often affectionately nicknamed "Clockwork Orange" after the plain orange livery of the new trains, although at the time of writing (2005) they are being repainted in the carmine and cream (with a small orange stripe) livery seen here.

In modern terminology the Glasgow Subway would be classified as a "mini-metro". This would be because when compared to mainline railway systems the Subway uses short 3 carriage trains of a smaller size which operate at much higher frequencies.

As an aside, the subway is not the oldest underground railway in Glasgow itself; that distinction belongs to a 3-mile stretch of the North Clyde line which nowadays is part of the mainline ScotRail franchise and runs in a sub-surface tunnel under the city centre between High Street and Charing Cross (not illustrated).

Liverpool also has some underground stations but here too services are provided by inner-suburban mainline trains operating as part of a mainline rail franchise. Known as the Loop & Link the system features two lines - one where trains travel under Liverpool City Centre linking lines to the north and the south of the city and another where trains from Birkenhead and the Wirral peninsula travel in a clockwise loop around Liverpool City Centre before returning back under the River Mersey towards the Wirral.

Whilst the Loop & Link opened in 1977 the tunnel under the River Mersey actually dates from 1886. It was built by the Mersey Railway - originally as a steam railway - and electrified in 1903, in the process seeing the Mersey Railway become the first steam railway "anywhere" globally to change over entirely to electric traction.

At one time similar 'city centre suburban mainline railway tunnel' systems were also planned for Sheffield and Manchester but it is understood that the people of Sheffield wanted to spend the available funds subsidising local bus fares whilst the national government point blank refused to provide sufficient investment funds for Manchester's scheme to be brought into reality. (It is said that the national government had declared "never again" after building the Tyne & Wear Metro's underground section, even though in Manchester the aim was solely to improve access to the city centre by merging two existing suburban electrified services which used edge-of-city-centre mainline railway so that they became one). Nowadays both cities have surface light rail systems - with Manchesters' Metrolink having started off as a street level variant of the failed Picc Vic Link which was so successful that it has been extended to other new destinations within the city, some of which re-use formerly closed railway routes.

The Tyne & Wear Metro is a regional rail system based on the city of Newcastle-Upon-Tyne where some stations are underground. When it first opened (in 1980) most of the system was effectively a re-electrification of mainline services that the former British Railways converted to diesel trains in the 1960's, although the underground section was brand new construction.

Although the Metro uses what are essentially light rail vehicles they are at the 'heavy' end of the scale, being designed to be compatible with mainline trains - a feature which has stood them in good stead for the 2002 extension to the nearby city of Sunderland, which is (mostly) over pre-existing tracks where the Metrocars provide local services and mainline trains operate longer-distance regional services.

Light rail / trams are also (usually) seen as a type 'short distance' transport; to avoid making this page too large they are looked at on a dedicated Trams & Streetcars page.

Of course Britain is not the only place with urban rail systems, but there are so many in major cities around the globe that it is only possible to mention a few of them.

Another city (in addition to London) which has both "smaller" and "larger" profile underground railway trains is the German capital of Berlin.

These three images show a recent type of train which was built in two versions depending on lines served.

Full-width inter-carriage gangways also feature on metro trains in other European cities too...

To avoid making this page too big automated (self driving) railway services are looked at on the Automated 'Driverless' Metro Systems page.

Although transport systems have not traditionally been seen as being places of beauty there is no 'law' as such which requires that stations should be solely functional but visually mundane / utilitarian.

Realising this, and that visually uplifting buildings represent environments where people may 'wish to be' many systems have built (at least some of) their stations with good design in mind. Sometimes this will add a comparatively small amount to the overall cost (often less than 1%) but it also helps attract passengers to the system and creates something which local people can be proud of. In the former Soviet Bloc nations politics also entered into the mix, with the cities deemed to be more important being given impressive stations that were designed along the theme of Palaces of the People. Often these featured valuable materials - such as different coloured marble and semi-precious gem stones sourced from various parts of the Soviet Empire, and were lit using chandeliers, adorned with mosaics, paintings, etc., so that they would often rival many an ancient stately home, chateau, art gallery etc.

Nowadays when building new systems or extending existing systems some cities employ architects of the highest calibre from around the globe, with the express intention of their designing stations to a cutting edge artistic brief - and apart from attracting passengers who just wish to travel from A to B these stations often also attract a global audience of students plus other people whose primary interest is in design & architecture who wish to see and photograph these visually distinctive buildings (stations). For similar reasons some systems also include works of art in their stations - busts, sculptures, bronze figures, stained-glass windows, etc.

It is only the intention of this page to mention this aspect of station design 'in passing', and even then only with respect to short distance urban transport railways. Further information and many photographs can be found on this excellent page at the Metro-Bits website
http://mic-ro.com/metro/metroart.html

Two Metros In Moscow???

Although not (yet) confirmed officially it has been suggested that Moscow has a second metro system at a deeper level than the public system.

This is said to be under military jurisdiction and was built to facilitate survival during a war / natural disaster and to act as a secret escape route for key personnel, should it ever be needed.

The only sort of validation which could be said to be in the public domain comes from other cities - such as Prague, Czech Republic - where rumours which talked of similar during the Soviet era were later found to be true, although the facilities were considerably less extensive than the rumours had led people to expect they would be. For the record, rumours also exist of a planet-wide deep level high-speed maglev system which links subterranean military bases and other facilities in the USA, Australia, etc.

The Flood Risk

In August 2002 heavy rains and consequential rivers bursting their banks resulted in severe flooding of large areas of Central Europe, and that included a large portion of the Prague metro. So severe was the damage that it took until March 2003 for the system to fully reopen.

The reasons why this occurred are not for this page to discuss, however with climate change (and more) in mind it is to be hoped that every conurbation which has an underground railway / metro / subway system has adequate and working flood protection systems, and would remember to use them if there was a credible risk of a flood event.

There would be nothing worse than trains full of passengers becoming stranded in deep level tunnels which are filling up with water. The risk is equally severe in cities where tectonic activity is a known issue (San Francisco, Japan), as it is in any city where there are rivers / waterways - including London, Liverpool, New York, Boston, Berlin, Paris, Singapore, Sydney, etc.

Contradictory Camera Policy / Breach Of Human Rights

When stations are entirely below ground potential passengers need a way of knowing that the station is there!

Often a transport system will have a special symbol which is used to denote station entrances - such as the stylised green 'M' symbol seen here adorning the roof of what would otherwise look like just an entrance to a pedestrian underpass to cross a road.

The topic of finding stations is looked at in greater detail on the Halts, Stops & Stations page.

Stations which are 'under the ground' need to be linked with the surface, and for the majority of stations this is usually done by means of moving stairways - aka: escalators.

Sometimes these stations are very deep and it can take several minutes to travel between the platform and the street, making the escalators almost seem like a mode of transport in themselves.

Escalators are looked at in greater detail on the Niche Transports page.

In Boston, Massachusetts USA they colour-code their urban transports according to the line on which they operate. For the subway there are four lines (Red, Orange - which I was advised serves some of the best avoided areas of the city - Blue and Green). The first three of these use 'proper' subway type cars and contrary to the international 'norms' feature red marker lights at both the front and the rear of the trains. The Green Line uses street compatible streetcars and instead features green marker lights at the front. Other colour-coded lines include "Purple", which is used for heavy rail commuter trains and "Silver", which is used for a Bus Rapid Transit Trackless Trolley service ("trolleybus" in British English) which also includes both surface and subterranean operations.

The tracks of Toronto's subway and streetcar networks (but not the Scarborough RT) are built to the unique gauge of 4ft 10 7/8in (1,495mm) rather than the usual standard of 4ft 8 1/2in (1,435mm). Although there are several theories there is no definite known reason for this, although it may be significant that the use of this gauge was established in 1861 (for the streetcars), this being ten years before Canada's adoption of standard gauge for rail systems. Although the subway system only dates from the 1950's it may be that the same track gauge as the streetcars was chosen because at one time serious consideration had been given to running streetcars through the tunnels and possibly having some subway routes run partially in tunnels and partially on city streets (possibly with the streetcars). Bearing in mind the cost of converting all the tracks and vehicles (and the lack of any real benefit in doing so), the unique gauge has remained to this day. The use of standard-gauge tracks on the Scarborough RT makes it impossible for there to be any track connection between it and the other lines, and so when its vehicles need anything more than basic maintenance they have to go by road to the suitably equipped subway maintenance facility. The Scarborough RT service is an automated urban transit and therefore is seen on the Automated 'Driverless' Metro Systems page.

Traditionally Toronto's subway trains have always featured half-width train driver's cabs, with passengers also being able to sit at the front and enjoy a clear view of where the train is going. However the newest trains (2009) do not offer this facility. Also deprecated are the corrugated metal sides.

On the island-state of Singapore they use what effectively is a high-capacity urban rapid transit metro as the basis for a still expanding regional transport system. In Singapore city itself the trains operate underground; elsewhere they mostly operate on viaduct. Internally the air-conditioned trains are designed for crush loads with just limited longitudinal seating and plenty of standing space. To encourage passengers to travel in less crowded parts of the train they all feature full-width inter-carriage gangways.

Bangkok, Thailand is a very large city where traffic congestion is such that gridlock is commonplace. Whilst it does have some rail-based urban transport the system is not as nearly as extensive as large conurbations in countries such as Japan, China, Singapore etc. The trains are also a rather short 3 carriages in length.

The 1997 Asian financial crisis is often blamed for the failure of one combined road and urban railway transport scheme (which was to be located over State Railway Thailand tracks), resulting in over 1000 part-built concrete pillars littering the planned routes, sections of which were subsequently blocked by the building of a new elevated toll road.

In March 2012 thieves stole metal scaffolding helping to hold up a structure which had been involved in weight testing. As a consequence a few months later some of the concrete beams then fell onto the railway tracks below them.

Whilst most urban railways use conventional steel wheels running on steel rails, a few use rubber tyred wheel systems.

Although rubber tyred trains had already existed on the mainline railways, the French city of Paris is credited as having pioneered the use of rubber tyres on urban transport systems. The impetus behind this is said to be that at the end of WW2 the many years of heavy use but relatively little maintenance had left the métro system in a very run down condition and converting to rubber tyres was thought to be a way in which the system could be renovated and rejuvenated.

The first Parisian rubber tyred train was introduced in 1951. Experimental in nature it operated a shuttle service between Porte des Lilas - Pré St Gervais over a section of track that was not in public service. The line closed again in 1961, although it is now proposed to re-open it as part of a new métro line. In 1956 line No.11 became the first full line to be converted. It was chosen because of its steep grades. Since then another three lines have been converted to rubber tyred trains, these being Nos. 1, 4, 6. Line 6 was converted in 1974 to cut down noise on its many elevated sections. However converting existing rail-based lines proved to be a very expensive process and is no longer done. For the record, whilst line 14 also uses rubber tyred trains this is because it was built this way from the outset.

More information about rubber tyred metros and their genesis can be found here:
http://www.emdx.org/rail/metro/principeE.html

Nowadays métro trains using French rubber tyred technology operate in half a dozen French cities as well as several major global cities including Montréal Canada, Chicago USA, Santiago (Chile), Taipei, Taiwan / China and Mexico City. Other rubber tyred systems also exist, especially in Japan and with short distance airport people-mover systems.

Whilst there are several variants in the implementation of rubber tyred systems, the core theme is for the rubber tyres to use twin parallel rollways, each of which will be the width of a tyre. Depending on city and the system builder these are typically formed of concrete, H-Shape hot rolled steel, or flat steel. Some systems also locate regular railway track between the rollways and the vehicles also have railway-style steel wheels with larger (taller / deeper) than normal flanges. In normal use these will be at small distance above the rails, their primary function being for guidance at points (switches/turnouts) and crossings. They are also needed in the case of a flat tyre. In Paris the steel rails also enabled mixed traffic with rubber-tired and steel-wheeled trains using the same track, particularly during the conversion periods. This use of two systems operating in parallel increases building / installation and maintenance costs. Systems without these tracks use other solutions for dealing with flat tyres and switching tracks at junctions.

The essential difference between rubber-on-concrete and steel-on-steel is that rubber-on-concrete generates more friction. This increased friction results in various advantages and disadvantages...

Advantages of using rubber-tyred trains (compared to steel wheel on steel rail):

• Smooth ride (with little "jostling" around)
• Faster acceleration - although more modern steel-on-steel rolling stock using distributed-traction with a high-proportion of powered axles has narrowed the acceleration/performance gap with rubber-tyred rolling stock.
• Shorter braking distances, allowing trains to be signalled closer together.
• The ability to climb or descend steeper slopes than would be feasible with conventional rail tracks. For steeper gradients conventional rail tracks often need to use a rack + pinion (cog wheel) technology.
• Quiet ride in open air (for residents and those outside the train).

Disadvantages of using rubber-tyred trains (compared to steel wheel on steel rail):

• Higher energy consumption than steel-on-steel
• A larger quantity of excess heat is generated.
• Weather variance - loss of traction-advantage in inclement weather (snow and ice).
• Heavier; especially where steel rails remain too.
• Tyre replacement cost.
• In-tunnel noise is higher than normal trains due to the roaring sound caused by the tyres.

Rubber tyres have higher wear rates and therefore need more frequent replacement. Although a pair of steel wheels are more expensive than a pair of rubber tyres, the frequency of their respective replacements makes rubber tyres the more expensive option. In addition, additional rubber tyres are needed for guidance using the side rollers. In tunnels heat dissipation can be an issue as eventually all traction energy consumed by the train - except any electric energy regenerated back into the power supply system during braking - will end up as heat. Often this necessitates ventilating the tunnels. For fire resistance reasons the tyres are inflated with nitrogen.

As the VAL system does not include steel tracks and wheels so to ensure correct route selection at junctions it uses a centrally located guidance rail. Away from junctions the mere presence of the side guidewalls is sufficient to provide the required steering functions.

By way of contrast, the entire rubber tyred network on the Parisian métro was designed to also be suitable for steel wheel trains and at junctions guidance is obtained by lowering the rubber tyre rollways so that the steel wheels engage the metal tracks and the trains are steered in the traditional railway way, which is by the wheel flanges.

Apart from Paris and Lyon the only other French city to have a rubber tyred métro system which uses twin axles is Marseilles.

More information about the several French (and other nation) métro systems which use the single axle VAL system can be found on the Automated 'Driverless' Metro Systems page.

Inspired by events in Paris, which at the time was converting some métro lines to rubber - tyred operation, the Montréal Canada métro - which opened in 1966 - became the first 'new build' system to choose rubber tyred technology. Being a more modern métro system it was engineered to avoid the sharp curves that are a feature of its Parisian rôle model; this allows the trains travel more quickly between stations and gives it an overall higher 'average' speed (ie: the total 'point to point' speed which includes the time spent during station stops).

To reduce weather disruption in the severe and very snowy winters, the Montréal métro is fully enclosed with almost all the system underground - although some stations were designed to allow natural daylight to reach the platforms.

Real-time passenger information display system inside the Montréal métro trains. Information supplied includes the name of the next station and (as here) interchange possibilities. When not showing travel information the displays show other local information, news, weather forecasts, etc., and paid advertising.


A video showing this system in use has been placed on the 'youtube' file-sharing website and can be watched (in a new window) by clicking either the projector icon or this link - http://www.youtube.com/watch?v=HG_zyodzp7g .

The French have also sold rubber tyred métro technology to a few others cities, sometimes with these cities also using localised variants of the same types of rolling stock that were being built (at the time) for the Parisian métro.

In Japan there are almost a dozen rubber tyred systems, these use home-grown technologies.

Sapporo's Nanboku Line opened in 1971 when it became the first such system to use a central guiding rail.

Other Japanese rubber tyred systems include the Kobe Port Island Line (also known as Port Liner) and New Transit Yurikamone.

Both of these use side guidewalls for guidance and are automated driverless systems so are often known as 'automated guided transits' (AGT).