InterCity 125
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An InterCity 125 train (often referred to as High Speed Train or HST) is a formation of two Class 43 power cars with a rake of Mark 3 carriages in between.
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[edit] Formation
A HST is a fixed formation 125mph (200kph) diesel train usually made up of 7 or 8 British Rail Mk3 carriages with a British Rail Class 43 power car on each end. This 'top-and-tail' arrangement removes the need for the locomotive to run round its train, instead employing bi-directional push-pull operation.
Before 2001, Cross-Country trains typically used seven coaches, with one fewer first-class carriage in the formation. In the early 2000s Virgin Cross-Country trains often used five-car formations, giving better acceleration and shortening journey times. In recent years Great North Eastern Railway (GNER) has added a standard-class carriage to its sets to provide extra seating, resulting in nine-car sets.
[edit] History
The concept of the HST dates from the late 1960s. British Rail's research division in Derby decided to pursue a parallel approach to future express trains. To complement the advanced technology tilting train project British Rail APT-E it was decided in 1970 to build two lightweight 125mph capable Bo-Bo locomotives to push - pull a rake of the new 23 metre long MK3 coaches. They were intended as a stop-gap until the APT was proven. These specialised locomotives had conventional buffers at the driving end only, although they did have an auxiliary cab at the other end to allow shunting at low speed.
Experience with the high-speed Deltic locomotives British Rail Class 55 had shown that a low axle weight was essential to avoid damage to the track at sustained high speed and that high-speed diesel engines were the only way to provide a good enough power/weight ratio. To power the HST up to 125mph each locomotive utilised a new diesel engine, the 12 cylinder Paxman Valenta, running at 1,500 rpm and developing 2,250 bhp . The 70 tonne total weight of the locomotive gave it a 17.5 tonne axleweight.
The prototype train of 7 coaches and two locomotives was completed in August 1972. By the Autumn it was running initial trials on the mainline and in May 1973 the prototype, now classified as Class 252, set a world speed record of 143.2mph. The concept was proven during trial running between 1973 and 1976 and British Rail decided to build 27 production HST's to transform Inter City services between London Paddington, Bristol and South Wales. The first production powercar (numbered 43002) was delivered in late 1975 and proved to be of a significantly different appearance to the prototype. The streamlined front end lacked conventional buffers and the drawgear was hidden under a cowling. The single cab window was much larger than the prototype and there was no driving position at the inner end.
Deliveries continued through 1976 and in October a partial service of HSTs running at 125mph began on the Western Region. A radical update of the standard BR livery was complemented by the 'InterCity 125' branding which also appeared on timetables and promotional literature. By the start of the Summer timetable in May 1977 the full complement of 27 class 253 sets (numbered 253001 - 253027) were in service on the WR and they completely replaced locomotive hauled trains on the Bristol / South Wales routes. Usage of the trains rapidly increased due to the speed and frequency of the HST service, an effect previously only seen when electric trains had replaced slower diesel or steam services. The displacement by HSTs of the British Rail Class 50 locomotives to slower services effectively finished off the last 'Western' diesel hydraulics British Rail Class 52 by early 1977.
The production of Class 254 (eight car trains) continued through 1977 for the planned East Coast Main Line services. Initially British Rail planned to fit uprated 2,500 bhp Valenta's to these longer HST's but this plan was shelved as the intensive running on the WR began to result in a high level of engine failures, often due to inadequate cooling. Indeed for a while the WR powercars were derated to 2000bhp. The class 254s began to work important ECML expresses such as the Flying Scotsman from the Summer timetable in May 1978. Within a year they had displaced the Deltics to lesser workings and reduced the journey time to Edinburgh by up to an hour.
In the early 1980s, the HST had truly caught the travelling public's imagination, thanks in no part to a memorable television advertising campaign fronted by Jimmy Savile, together with the advertising strap-line "This Is The Age Of The Train". BR enjoyed a boom in patronage on the routes operated by the HSTs, and InterCity's profits jumped accordingly - with cross-subsidisation in turn safeguarding the future of rural routes which had been under threat of closure since the Beeching Axe of the 1960s.
Production of HSTs continued until 1982, allowing them to take over services from London to the West Country, many Cross-Country express trains and finally the MML Midland Main Line services. In total 95 HST sets and 197 Class 43 powercars were built between 1976 and 1982.
Ultimately more Mk3 trailer cars were built in the 1980s for the Western Region class 253s allowing them to become eight-car rakes in common with those used on ECML & MML services. During the 1990s only the Cross-Country sets remained as seven car rakes with just one First Class carriage.
[edit] Usage
As of 2004, HSTs are used by First Great Western (84 powercars), Midland Mainline (63 power cars) and GNER (23 powercars). From 1997 to 2003, HSTs were used by Virgin Trains until they were replaced by Voyager and Super Voyager DMUs. In 2004 Midland Mainline reduced its HST fleet in favour of Meridian DMUs. Network Rail also uses an adapted HST for its New Measurement Train.
The First Great Western HSTs have 472 passenger seats and storage for 6 bicycles.
The design was also used as the basis for the Australian XPT, which uses specially-built coaching stock, and has a lower top speed of 100 mph (160 km/h).
In 2006, it was announced that Grand Central, a new open access operator on the ECML, would use Mark 3 coaches pulled by Class 43 power cars on its newly inaugurated services between London and Sunderland.
[edit] Liveries
The original Inter-City 125 livery was blue and grey, with a yellow front (for visibility) continuing down the side of the power cars. This led to the nickname 'flying banana'.
The second livery, was mostly grey power cars with a white band along the middle, yellow underneath the white band, with the InterCity colours (cream, red, white, brown) for the parcel compartment of the power cars and the coaches.
It was brownish-grey, dark grey (almost black) around the windows with a red and white stripe below the windows, and retaining the yellow bands on the power cars. A later variant of this livery saw the yellow side-bands replaced with light grey and did not feature the British Rail name or logo: it carried a new INTERCITY logo, with the name in serif type and an image of a swift (known as 'Roderick').
After the privatisation of British Rail, individual train operating companies painted the HSTs in their own colour schemes, with some lasting longer then others.
The current schemes are
- First Great Western: Originally Green and Cream but now replaced by Standard First Group intercity, however a new colour scheme is being rolled out consisting of a blue gradient body with pink doors
- GNER: Dark blue body with red/orange stripe and doors.
- Midland Mainline: White coaches with dark green power cars
Additionally in 2005 Cotswold Rail bought a surplus HST set for spot hire and charters, being repainted into their silver livery. One powercar was in Hornby advertising livery. However both powercars were purchased by First Great Western in 2006.
There are several Mark 3 vehicles used in the Royal Train formation. These vehicles came from the prototype class 252 vehicles, visibly identifiable by different window frames. These vehicles still see regular service transporting members of the Royal Family and their entourages around the country. The entire Royal Train is painted in a deep maroon livery.
Network Rail have also converted several HST vehicles into a Track Measurement Unit known as the Network Rail New Measurement Train.
In 2004, First Great Western announced a major overhaul upgrade for their Class 43 locomotives (125 power cars), including a new MTU engine. Two Power Cars are currently undergoing trials in service with the new engine. In 2005, they undertook a trial refurbishment of a pair of 125 coaches to bring them up to modern standards. Another coach has been refurbished with experimental aircraft style seat back screens. As part of the Great Western francise commitments First Great Western have announced that they will be refurbishing the entire fleet as well as re-engining all Powercars with the MTU engine [1]
In January 2006 the first batch of power cars were taken to Brush Traction to have MTU engines fitted.
26 of Great Western's 125 fleet are to be refurbished into a high density layout of mostly airline seats for services in the M4 corridor to Bristol and Cardiff, to improve acceleration the Buffet cars will be removed. The remainder will be refurbished with new seating (leather in First Class), at seat power points and retain the buffet for the long distance services to Swansea and the Westcountry.
[edit] Replacements of the InterCity 125
The first replacement of the InterCity 125 train occurred from 1988 on the East Coast Main Line, seeing the InterCity 125 partly replaced by the InterCity 225 as the line to Edinburgh was electrified. However some HSTs were retained for services to Aberdeen, Inverness and Hull.
In more recent times, InterCity 125s have been replaced (or augmented) with DMUs such as Class 180 Adelante, Class 220 Voyager, Class 221 Super Voyager and Class 222 Meridian DMUs.
These new DMUs have better acceleration than the HST due to a higher power/weight ratio, typically 30% more. However it is widely accepted that such vehicles cannot ever approach the high level of comfort and noise reduction afforded by the Mk3 coaches of the HST. The sound and effect of a vibrating underfloor diesel engine is now widely recognised as being totally unsuitable for long distance Inter-City trains. In 2005 the concept of HST2 was mooted by the Government and the Rail Industry as a like-for-like replacement for the HST fleet. It is uncertain whether this concept will be developed and existing HST operators such as GNER and First Great Western decided in 2006 to refurbish their HST fleets. Brush traction is to fit modern quiet and fuel-efficient MTU4000 engines to the powercars. It is anticipated that this will give the HST at least another 10 years in front line service. First Great Western have purchased 14 off-lease ex Virgin powercars and intend to replace the modern Adelante units with 1980s vintage HSTs!
[edit] See also
- Class 43 locomotives - The power cars sandwiching the Mark 3 coaches on InterCity 125 trains.
- Mark 3 coaches - The coaches sandwiched by the Class 43 power cars on InterCity 125 trains.
- High Speed Train - For information about high speed trains in the United Kingdom.
