Bilevel car

The bilevel car (North American English) or double-decker (British English) increases the passenger or freight capacity of a train without lengthening a train.

Problem and the Double Decker Design Solution

Once the maximum train length and trains per hour at a station are achieved, then double decker cars are the only way to avoid building new rail lines. This is usually done by putting the lower floor between the wheels, closer to the rails, and then adding an upper floor above. This design fits under more bridges, tunnels and power wires (structure gauge). For cost and safety, this design also minimizes car height (loading gauge) and lowers the center of gravity. There are two basic designs for bilevel cars. High platforms use "split level" design. Low platforms use "two floor" for level entry onto the lower floor. Occasionally a third, very tall "two floors over-wheel" design is used. This is a traditional single floor car "with a second story" design with steps from low platforms up to a traditional floor height.

Platform Height and Floor Heights

There are four height measures above top rail that matter. Platform height, traditional floor height, downstairs floor height and upstairs floor height. Platform height determines level entry height for wheeled luggage, children in push carts, wheel chairs and bicycles. Platform height is ideally standardized across all stations the train serves. Traditional rail car floor height matters for end doors connecting to existing single floor rail cars. Downstairs or lowest floor height is primarily determined by the thickness of the beams connecting the span between the wheels and bogies of a rail car. The upstairs floor or highest floor height is above the lowest floor and must fit under bridges and tunnels. Level entry floor height must match the platform height. Hopefully the either the traditional or downstairs floor height already matches the platform height. Despite the name "bilevel" or "double decker", for maximum compatibility the rail car will have up to four different floor heights. Using outside steps to avoid having a level entry from the platform is troublesome.

Common High Platform Design

Most high platform trains have level entry over the bogie with stairs inside the car for the upstairs and downstairs double decker floors. These cars are designed for high platform rail line, such as all the existing stations with a standardized high platform and the rolling stock end doors that connect to any traditional single floor car and even roof line aerodynamics. There are three floor heights (upstairs, downstairs, and platform levels) in these "split level" cars. The entry level floor area has to be big enough to hold wheel chairs, children push-carts, and even wheeled luggage. This high platform "split level" double decker design is the preferred design in urban and commuter applications, and can be designed to matched to any rail platform height. Car roof lines lengthwise are sloped at each end (not flat) for aerodynamic connection to single level cars and the space is unused. Bombardier commuter cars are 15 ft 11 inch (4852mm) high.

Common Low Platform Design

Most low platform double decker trains have level entry onto the lower level of the car, allowing wheelchair access. There are two floor heights (upstairs and downstairs) in these "bilevel" cars. There is a staircase between floors inside the car. Connecting doors between cars are at the (higher) upper floor height and not at the traditional height. These low platform cars use low platform stations across the Western US, because the traditional single floor trains all had exterior entry steps to maximize flexibility (emergency and temporary stops) and minimize infrastructure costs. There are no examples of two floor platforms, so there are no platform doors on the upper floor. Car roof lines lengthwise are flat for connecting doors to the upstairs of bi-level cars. Connecting directly to a single level car causes drag and connecting door problems. Bombardier Amtrak Superliner is 16 feet 2 inches (4928mm) tall.

Uncommon Very Tall Design

There are several very tall bilevel cars (e.g. Colorado Rail has convert|19|ft|9.5|in|m or 6033mm). They typically are described as a traditional rail car with a second story. Most of these cars serve low platforms so have exterior steps up to the traditional "over-wheel" floor height (e.g. US 51" 1295mm). End doors connect at the traditional height of existing rolling stock. Some cars have upstairs end doors as well. Upstairs and downstairs connect by interior stairs. These cars can fit the most able people, but lack level entry. Some cars are self-propelled Multiple Units so using traditional floor heights appears fixed. In towed cars it is possible to lower the downstairs floor between the wheels/bogies so that level entry is possible with more than 500 mm of added headroom and interior steps from that floor to the to the traditional floor.

Containers

Similarly, one may also have bilevel cargo transport. In intermodal freight transport, many modern types of container well cars cars are designed to accommodate "double-stacking." Where passengers and freight rail use the same lines, containers may have required increasing the lines structure gauge. But passengers and freight are usually separated. Containers are convert|8|ft|m wide and convert|8.5|ft|m tall or sometimes convert|9.5|ft|m tall. Therefore double stack freight is 17, 18 or convert|19|ft|m above well car floor height.

Alternatives

The alternatives to double decker cars are usually explored first, before going double decker.

* Add cars to existing trains: this works until all platform and sidings capacity has been used. Until that occurs, lengthening trains is preferable to changing the loading gauge and structure gauge of the rail line. Longer cars (without changing structure gauge) does not add much, because cars are often required to be narrower to negotiate curves. In countries with larger structure gauges for freight traffic (such as the United States) this is often less of a concern.

* More trains: increase the frequency of trains scheduled. This flexibility can be very popular with passengers until rail line traffic is congested.

*Changing seating: fitting more (smaller) seats into the same space and/or decreasing the pitch (distance between seats) on existing vehicles.

*Track amplification: building additional rail lines and platforms is expensive and often requires land acquisition and service disruptions.

If freight service has increased the structure gauge, and the rail line needs to minimize "per car" maintenance and staffing costs double deckers can pay for themselves more quickly than buying single floor cars of equal capacity. Wheelchair accessibility laws encourage level entry solutions frequently provided by double decker rail cars. Profitability is encouraging double decker rail cars adaption before many alternatives.

Double-deck cars

Manufacturers

Passenger cars are manufactured by Bombardier, Kawasaki, Colorado Railcar, IC2000, and several others.

Bombardier and Kawasaki manufactured most of the High platform "split level" commuter rail cars in the North East United states.

Bombardier made the Amtrak Superliner Low platform "two floor" rail cars for the Western US area.

Colorado Railcar make DMU and IC2000, of Switzerland, make EMU, where the Multiple Units are self-propelled cars, much like subway cars. Colorado Railcar cars are very tall (19' 9.5" or 6033mm) cars for low platforms with steps entry to a normal (51" 1295mm) floor and an upstairs. The IC2000 cars are strictly low platform design.

Australia

In 1964, Tulloch Limited built the first double decker trailer cars for use in Sydney. They ran with single deck electric motor cars. The first prototype double deck motor car was built by Comeng in 1969 and production versions entered service in 1972. All CityRail electric commuter trains in Sydney are now double deck. They all have two doors per side per carriage, with a vestibule at each end at platform height. Well-known examples of these trains are the Tangara and Millennium trains. The Sydney double deck commuter trains are 14'-4.5" or 4380 mm high.

The Public Transport Corporation in Melbourne ordered a prototype Double Deck Development and Demonstration train in 1991. It suffered frequent breakdowns and spent long periods out of use. It was finally withdrawn in 2002 and scrapped in 2006.

Canada and USA

Other designs, including rolling stock made by Colorado Railcar Manufacturing, Budd, Pullman-Standard, Bombardier and others, have the entrance on the lower deck rather than an intermediate level. Amtrak Superliners are double-decker cars of this variety, with the entrance a step or so up from the lowest station platform level, or at the level of slightly higher platforms, and allow passage from car to car at upper-deck level.

The northeastern US can accommodate split level (double deck) cars only if they are no higher than convert|14.5|ft|mm|0|abbr=on. These double deckers run on the Long Island Rail Road: [http://www.mta.nyc.ny.us/lirr/] : and on New Jersey Transit: [http://www.njtransit.com/] : (contact Bombardier Transportation: [http://www.bombardier.com/index.jsp] ) due to the size of the loading gauge (i.e. bridges, tunnels, etc. are too low). The designs found on the Long Island Rail Road and New Jersey Transit are based on a 1930s Pullman Sleeping Car design for the Pennsylvania Railroad called a Duplex Sleeper. This design provided 24 Roomettes on two levels with the lower level depressed between the trucks. This idea was copied in 1947 for the Long Island Rail Road, making use of a standard P-70 that was electrified. The new cars have the entire center sill lowered to the minimum level between the trucks, providing a depressed floor on that level. The upper level is stacked on top between the trucks. At each end, the a common floor is located in the normal position, with four doors on each side, two of which can be reached only at high level platforms, while the other two are in the normal Vestibular position, with stairs to reach low level platforms. Similarly the structure gauge of the Mount Royal Tunnel limits the height to 14'-6" or 4420 mm [http://www.emdx.org/rail/DeuxMontagnes/Tunnel/CoupeTunnelDouble.gif] .

The double deck cars operated by Chicago's Metra regional rail service are known as "gallery cars" as there is an open space between the two sides of the upper deck, allowing ticket collectors to check tickets on both levels from the bottom level. Chicago does not have the loading gauge problems that affect most eastern USA cities (although ex-Metra cars operate on MARC in Baltimore, Maryland), so all Chicago's commuter rail rolling stock is full size bi-level, and many of Amtrak's Superliner trains to the western USA originate from Chicago.

The first bi-level gallery cars were introduced by the Chicago, Burlington & Quincy railroad in 1950.

Finland

In Finland, VR began operating double-decker sleeping cars on 1 February 2006. The two-bed cabins on the upper deck have toilets and showers while cabins on the lower deck use shared ones. VR also operates double-decker Inter City trains with at seat power supplies for laptops.

France

The Chemin de Fer de l'État in France ran voitures à 2 étages double-deck suburban coaches from 1933. Its successor, the SNCF, has been running VB2N double decker coaches since 1975, VB2N were introduced from 1975 as a replacement of the État cars.

Since the late 1980s, SNCF has been running double-deck RER trains. SNCF runs double-deck TGV cars on heavily used high-speed services. Many suburban, regional and high-speed services are operated by double-deck DMUs, EMU, coaches and TGV. The French loading gauge dictates that the double-deck cars have a maximum height of 4200 mm or 13'-9.35".

Hong Kong

MTR and formerly KCRC operates double decker carriages with the KTT train sets. These cars were manufactured in Japan by Kinki Sharyo T1 (T1C), T2 (T2A, T2B).

Japan

In Japan, double decker trains are used either to show better scenery, or to increase seat capacity.

Double deckers for scenery

The first Japanese double decker train appeared in 1904. It was Type 5 train of Osaka City Tram, once operated by Osaka Municipal Transportation Bureau. The tram car, however, soon took away its second floor, due to the complaints by residents along the line, concerning their privacies.

The first double decker heavy rail train, Kintetsu 10000 Series, appeared as late as 1958. The series, nicknamed Vista Car, became popular trains used for limited express services. Its successors are still used by Kintetsu. The idea of Vista Car is said to come from Vista Dome Car in United States. The first double decker high-speed rail in the world was JNR 100 Series Shinkansen used from 1986. The train was purely introduced to improve its luxury. As such, the first floor of the train was a dining car.

Other double decker sightseeing trains include JR Shikoku 5000 Series, JR Hokkaidō Kiha 183 Series, Keihan 3000 Series, Keihan 8000 Series, JR Central 371 Series, Odakyū 20000 Series, and others.

A similar kind of trains are largely single decker trains with vehicle cockpit domes on the "second floor", to allow the better front view. This kind of trains include Panorama Cars by Meitetsu, Romancecars by Odakyū, and Mount Fuji Limited Express by Fujikyū. Its origin is said to be ETR 300 Settebello in Italy.

Double deckers for capacity

The first Japanese double decker trains built to increase its capacity were 211 Series and 113 Series, both by JR East, 1989. These trains were "Green Cars" (Japanese for first class cars), needing more seats than standing spaces. JR East also introduced double deckers with normal class seats, namely Kuha 415 Series for Jōban Line, 1991, and 215 Series for Home Liners, 1992. JR East continues to use double deckers, including E217 Series for Sōbu Line (Rapid) and Yokosuka Line, E231 Series for Tōkaidō Main Line, Utsunomiya Line (Tōhoku Main Line), Takasaki Line, and Shōnan-Shinjuku Line, and E531 Series for Jōban Line.

In Japan, however, double decker commuter trains are relatively fewer than those used in Europe or North America. This is because Japanese commuter trains can be much more crowded than Western counterparts. Therefore, they generally need more standing spaces than seats. Also, Japanese train cars are 20 m long or less, and it is technologically difficult or inefficient to have more than 2 doors on each side of double deckers that size. Japanese crowded trains, however, generally need 4, 5, or 6 doors on each side to make smooth boarding and alighting.

JR East also introduced E1 Series and E4 Series for its Shinkansen Lines. Unlike 100 Series in the past, these trains, nicknamed Max, all consist of double decker cars, and are purely made to increase their capacities. In that sense, these trains are similar to TGV Duplex in France. There are also some double decker sleeping cars made to increase their beds or compartments, like CityNightLine trains in Europe. This includes JR West 285 Series for Sunrise Izumo/Sunrise Seto and JR East E26 Series for Cassiopeia.

United Kingdom

In the United Kingdom, and countries with a similarly small loading gauge, the railway system cannot accommodate double-deck trains. A modest attempt at double decking was made in 1948 on the Southern Railway with the two trains of the Bulleid 4DD class. Although innovative, with stepped compartments, where the bottoms of the upper seats are above the heads of the people on the lower level, but the feet of the people above are not, see [http://members.tripod.com/~dart75/bddscut.htm] , the loading gauge severely restricted their use and they were removed from service in 1971.

weden

SJ AB operates 43 double decker EMUs of class X40. The EMU comes in a two-coach version and a three-coach version. The trains are mainly used in the areas around lake Mälaren and in the trains between Gävle and Linköping.

witzerland

Double Deckered commuter trains are used in the Zürich area. Two types of trains are used, an older type consisting of an electric locomotive with double decker cars, and Electric Multiple Units (DMU or EMU) where the motors are on-board the car. The SBB-CFF-FFS also operates the IC 2000 double decker passenger coaches in most of Switzerland.

Other countries

Indian Railways operates intercity trains between Mumbai and Surat, and Mumbai and Pune .

In the Netherlands, there are two types of double-deck trains, the DDM and the DD-IRM, also called Regiorunner: see Trains in the Netherlands. The DD-IRM, is an example from the Netherlands, of High platform (split level) double decker cars. It is one step up from the station platform to the entrance, and from there seven steps upstairs or four steps downstairs.

In Spain several lines of Cercanías (Renfe's commuter rail service) use double-deck trains. Bombardier's double-deck rail cars in Germany are also used extensively on suburban trains by the DB. The same rail cars serve many of the routes on the Israel Railways network.

In Hong Kong, the Kowloon-Canton Railway Corporation uses double-deck cars, named "Ktt", on its cross-boundary route between Kowloon and Guangzhou. In January to May 1998 the "Ktt" cars were used to serve between the Hung Hom and Lo Wu stations. The "Ktt" cars have lower bottom floor than the ordinary single-deck cars serving on the same pair of tracks.

Gallery cars

Because of the two levels being separate on most cars, there is a physical limitation on the conductor, as it is difficult for him to verify, collect payment and sell tickets to such a large concentration of passengers in one car on each level, owing to the sometimes short distance between stops.

The ingenious solution came in the form of the design of the "gallery" car, which featured upper levels, which were really mezzanines running along both sides of the car, with an open area between the mezzanines, hence the term "gallery". This enabled the conductor(s) walking along on the lower level to easily reach up and punch/validate tickets of the passengers seated on the mezzanine level.

Passengers would simply place their tickets in clips along a lengthwise panel, located slightly above the conductor's head and within easy reach. The conductor would then quickly check tickets and move to the next car.

An example is the cars provided and leased in the U.S. by Midwest Transportation & Development Corporation of Chicago. They are of a design proven in service and steadily refined since their introduction in the 1950s. These cars, known as "bilevel gallery cars", are among the most successful designs developed, and are currently in daily use in Chicago, San Francisco, and Montreal (Agence métropolitaine de transport). They provide high capacity (155 to 169 passengers each) and use standard, off-the-shelf components, without relying on proprietary, expensive and hard-to-get replacement parts. Chicago's commuter rail system Metra is currently receiving new versions of these cars and Caltrain, the San Francisco area commuter rail authority, has recently overhauled its fleet.

Another advantage of bilevel gallery cars is the relatively low first step of the vestibule entrance to the car, which is 14 5/8" (371 mm) above the head of the rail. The advantage of this is that commuter rail operators do not have to spend scarce funds on building high-level platforms; a low-level platform is all that is necessary, at a far lower cost. This can be a major disadvantage as well, as many commuter rail systems prefer high-level platforms and increase loading and unloading times substantially, and greatly improve access to trains for the disabled. Also, older (70's era) bi-level cars are notoriously uncomfortable, and tend to be disliked by rail agencies that operate them alongside newer equipment.

Virginia Railway Express (VRE) and MARC (Maryland Rail Commuter) are also owners of gallery cars in the Washington DC Area.

Double-deck trains often have curved windows upstairs. In the dark and in tunnels this causes a distorting mirror effect.

Double Decker Rolling Stock Designs in Ascii Art

ee also

*Bombardier BiLevel Coach
*Superliner (railcar)
*Dome car

External links

* [http://www.cl.ais.net/~dbehr/7600PullmanPhotoPage.html A photo of gallery car]