The High Speed Diesel Train (HSDT) was authorised by BR in the early 1970s as a stopgap during development of the Advanced Passenger Train (APT). Following evaluation of the prototype set and a change of name to the High Speed Train (HST) BR put together a proposed plan for HST introduction.

Sets were ordered in batches starting with 27 for the Western Region, followed by 32 for East Coast Main Line (ECML) duties. Further orders followed with 14 sets ordered for West of England services and 18 sets for Cross Country use. A final order was for four additional 8 coach sets for use on the ECML, though these were in fact delivered before the Cross Country sets. Following the difficulties in obtaining investment approval for this final batch, BR concluded that the likelihood of further successful investment submissions was low and the HST production line shut after 95 sets had been delivered.


The first production HSTs entered service on British Rail’s Western Region in August 1976, with 125mph running implemented from that October’s timetable change. The 7 coach sets were used on services between Paddington and Bristol/South Wales and allowed the 125mph capability of the sets to be fully utilised over much of these routes. Maintenance allocations were divided between Bristol St. Philip’s Marsh and Old Oak Common, purpose built facilities were provided at both depots.

HSTs made their debut on the ECML in 1978 and there followed a programme of line-speed improvements that enabled them to operate to their full potential. Initially services ran from Kings Cross to West Yorkshire, Newcastle, Edinburgh and Aberdeen, all using 8 coach sets. As business grew, HSTs started reaching new destinations such as Hull, Cleethorpes and Middlesbrough. To cater for this an extra four 8 coach sets were ordered, although five sets were actually delivered with one set diverted from the second tranche for the Western Region. Four new or refurbished depots were provided at Bounds Green, Leeds Neville Hill, Newcastle Heaton and Edinburgh Craigentinny. Heaton was used at first as the commissioning depot, though this role was later undertaken by Neville Hill.

43056 hurries through Doncaster leading a crew training run in 1978. (Paul Webster)

The earliest years of HST operation coincided with a change from the traditionally engineering led railway to one that was more commercially driven. From their introduction HSTs had proved popular with the travelling public resulting in a significant increase in passengers and, of course, revenue. This became known as the ‘nose cone effect’ and is perhaps the only equivalent in diesel traction of the well known ‘sparks effect’ that invariably accompanies electrification schemes. As their commercial appeal became recognised, HSTs were no longer restricted to those routes that did justice to their high speed capability. They were introduced to new routes not noted for high speed running but where there was considerable passenger demand for them.

West of England services were always considered for HST usage, even though full 125mph running is limited to the stretch from Paddington to Reading. However, HSTs offered an attractive commercial proposition and thirteen seven coach sets were built, fully entering service in May 1980 from Old Oak Common and St. Philip’s Marsh depots, following a series of problems as a result of a change in traction motor supplier. Plymouth Laira depot was upgraded to carry out servicing and to accommodate the allocation of new HSTs for the next and final batch of HSTs on the North East – South West route. Whilst there was limited scope for high speed running along the Cross Country lines, their superior acceleration and braking still made it possible to reduce journey times. Coupled with the ‘nose cone effect’ already mentioned, HST was felt to be a worthwhile investment and eighteen 7 coach sets were built, entering service from late 1981.


Just as soon as the HST deliveries had been completed in 1982 a number of changes were made to the way the fleet was utilised. Instead of being seen as simply another train fleet the InterCity sector of BR, under the guidance of Director Cyril Bleasdale, started to see their new HSTs as a valuable business asset from which the best possible utilisation should be extracted. This change of thinking coincided with an economic slowdown, increased competition from road coaches following deregulation and the subsequent reduction in demand for long distance travel. The InterCity services from St. Pancras to the East Midlands and Yorkshire had missed out on getting their own fleet of HSTs although the fleet of aged locomotive hauled trains were in need of replacement.

43133 seen wearing the InterCity Executive livery at Cardiff Central

Partly due to the falling demand for services and partly due to improved utilisation, 5 HST sets were released from the Western Region fleet, whilst three sets were released from the Cross Country fleet by the retention of some locomotive hauled operation on the NE-SW route. Allocations were shuffled within the WR based fleets so that 253019-027 (43038-055) and 253056-058 (43193-198) could be reallocated to Leeds Neville Hill during October 1982. Two spare sets were resourced from the ECML fleet so that a total of 10 sets could be provided to operate a near full HST service on the Midland Main Line. No depot facilities were provided for the Midland Main Line services, instead they ran empty to/from Bounds Green at the London end of the route and empty between Sheffield and Leeds Neville Hill at the northern end of the line. As depot facilities and spare resources were shared with the ECML fleet the entire ‘Eastern’ fleet simply became regarded as a common user between both lines, and this situation prevailed until privatisation loomed in 1993. The full Midland Main Line HST service commenced in May 1983 after the resignalling of almost the entire route, and electrification of the line between St. Pancras and Bedford had been completed.

The ECML HSTs were ordered and built on the strength of operating an hourly fast service between Edinburgh and London, but a purely Edinburgh to London service would lead to poor utilisation as arrivals wouldn’t be received from London until after 1130 and sets reaching Edinburgh after 1730 would be unable to form another productive journey back to London. This led to the concept of running beyond Edinburgh in marginal time, so rather than standing on the depot in Edinburgh between 1800 and 1100 the set could be used to run through to Aberdeen and form a morning Aberdeen to London service which would take up one of the departure ‘slots’ from Edinburgh. From the start of HST operation on the ECML there had been a modest operation of HSTs through to Aberdeen in marginal time where a small maintenance shed had been built to allow light overnight servicing to take place. The use of marginal time running later allowed the introduction of a HST service from Glasgow Queen St which conveniently provided for the Glasgow to Edinburgh line commuter market before running through to Kings Cross, whilst at the other end of the route one of the later Kings Cross starting sets would run empty to Peterborough to form a busy commuter run before starting its normal booked work.

In the summer of 1984 the use of HST sets in marginal time was taken one step further by the introduction of an experimental through service to Inverness which was formed by extending the 1200 from Kings Cross to Edinburgh. The morning service left Inverness early enough to form the 1130 Edinburgh to Kings Cross. The new service was a success and became a permanent all-year round feature of the timetable and continues to this day in the hands of Virgin East Coast.

When the Cross Country HST service was first operated the new fleet replaced locomotive hauled trains on most of the key services along the North East to South West route corridor. The early 1980’s Cross Country service ran hourly in each direction, with a sporadic service provided along the North West to Thames Valley/South Coast axis, entirely using locomotive hauled stock. The intention was that passengers would change trains at Birmingham New St if they wished to travel between two points not served directly, this was unpopular amongst many of the mostly leisure travellers along the route, e.g. family groups or the elderly. The hourly service was becoming unviable in the face of falling demand, so a revised service was implemented which saw two HSTs operating daily between the South West and Manchester, and one between the South West and Liverpool with all operation north of Birmingham being ‘under the wires’. Fleet reshuffles saw the Manchester services become locomotive hauled but the daily HST service to Liverpool was retained until 1994.

East Coast Electrification

HST domination of the ECML was to be short lived as June 1984 saw the announcement that finance had been approved to electrify the route and provide a new fleet of trains at a cost of £306m. Because the services had been so radically transformed by HSTs just a few years earlier, the principal driving force behind the project was the desire to cascade the valuable HSTs to other services allowing the withdrawal of older and more costly to operate stock. At one stage it was intended that the displaced HSTs would pass to the ‘Secondary InterCity Network’ and see use on services such as Edinburgh – Glasgow and North Trans-Pennine. However, the former services were part of the Provincial Sector who were moving to a Sprinter operated railway. Network SouthEast (NSE) also showed an interest in sets for the Waterloo – Exeter route in a shortened 2+6 formation; however NSE were also moving to multiple unit operation. In reality, by 1988 InterCity had begun to realise that the HST was a unique asset. Dr. John Prideaux, Sector Director of InterCity described the HST as ‘an outstanding achievement, fully equal of TGV’ and from then on it was evident the displaced sets would be staying with InterCity.

The transfer of the first main route between London and Leeds to electric traction was planned for April 1989, the electrification itself ran well ahead of schedule and the new Class 91 locomotives would start being delivered in early 1988. The new Mk 4 carriages were going to be delivered later than planned so InterCity came up with the innovative solution of replacing one power car of eight HST sets with a Class 91 so the start of the Kings Cross to Leeds electric service could be brought forward to Spring 1988. The other power car on each of these sets was converted to become a ‘surrogate DVT’ (Driving Van Trailer), these power cars were fitted with TDM equipment and other controls to allow the Class 91 to be controlled remotely from the modified HST power car. As the Class 91’s train supply was of the older DC ETH type (and thus incompatible with HST Mk 3 stock) the DVT Class 43 would continue to provide power to the train’s auxiliaries, leaving the Class 91 to provide all the traction power. The HST power cars were visually altered by the fitting of conventional drawgear and buffers in place of the lower nosecone fairing. Internally a new bank of switches was provided on the cab desk and the TDM equipment was accommodated in a cabinet in the luggage van area. Eight HST trailer sets were modified by the fitting of buffers and a drop-head buckeye at the guards compartment end of the TGS coach, this meant that the Class 91 would always be attached at the standard class end of the train whilst the modified power car would be attached at the first class end.

The first two power car conversions (on 43123/014) were carried out at the Derby Engineering Development Unit, whilst the other six (43013/065/067/068/080/084) were converted by the diesel repair shop at Stratford. Initial trials took place on the West Coast main line during November 1987 in order to prove the operation of the TDM equipment using 43014/123.

Operation of the Class 91/’surrogate DVT’ formation on Kings Cross to Leeds service commenced in March 1988 and after a few weeks of operation it was found that the power cars were suffering from spending all their time idling on just 1000rpm, and their traction power was reinstated creating 8000+hp formations capable of quite brisk performances! As the deliveries and commissioning of Mk 4 sets took place the later in 1988 the DVT modified power cars were released back into normal duties.

Cross Country Fleet Expansion

Prior to electrification there were 34 HST sets allocated to East Coast spread between Bounds Green, Neville Hill, Heaton and Craigentinny and 25 of these were to eventually be transferred away as a direct result of electrification. InterCity identified 3 distinct areas to benefit from the cascade, these being:

  • Enhancement of Cross Country services with replacement of older stock
  • Replacement of Loco-hauled trains on the Euston – Holyhead services
  • Increase in capacity on Great Western as a result of rising demand
43034 at Bristol in Intercity ‘Swallow’ livery

Edinburgh Craigentinny was chosen to operate the bulk of the new Cross Country services. Eleven sets with power cars 43013/014/062/063/065/067-071/078-080/084/090-094/097-100/123 were transferred with all sets being fitted with short swing link bogies to allow operation over former Southern metals. The service introduction took place in 2 stages. Stage 1 was effective from July 8th 1991, with power cars 43013/014/062/063/065/067-071/078-080/084/091/092/093/094 moving to ICCP EC and principal services ‘The Dorset, Devon and Cornish Scot’ services going over to HST operation, bringing Poole into the HST network and slashing a massive 65 minutes off the journey time between Poole and Edinburgh. Stage 2 took place on September 30th 1991, the remainder of the new fleet being transferred to EC and another six services going over to HST including ‘The Wessex Scot’. The ICCP pool was also split before stage 2 commenced with the EC fleet forming a new ICCS pool, the ICCP pool code being retained for Laira and Bristol St. Philip’s Marsh allocated vehicles.

The cascade to Cross Country allowed the withdrawal of almost 100 Mk 2 coaches and the remaining Mk 1 RBR catering cars and created a fully air-conditioned fleet on Cross Country.

West Coast required 3 sets to convert the Holyhead – Euston services over from loco-hauled operation to HST. The West Coast operation was a logistical problem for InterCity with the operation being out on a limb from a traditional HST depot. The solution was ingenious in that the West Coast fleet would be provided by Great Western with sets running empty between Euston and Old Oak Common. On paper a new pool was created, InterCity West Coast Power Cars (IWCP) based at Laira, although in practice any Great Western HST worked the services. The Western Region were to eventually receive 28 power cars from East Coast with 43040-042/086-089/101-103/122/152-162/193-198 making the move – 43160/161 were the first to arrive during May 1989. The cascade of HSTs also allowed Western Region sets to be strengthened to 2+8 and this, together with the running of additional services following the arrival of complete sets, allowing a large increase in passenger capacity.

Following a summer of crew training, HSTs took over the North Wales duties on 30th September 1991, the IWCP pool being created on the 29th September and initially receiving 43088/089/101-103/143. On the 12th April 1992 these were swapped for 43141/142/144-148 along with 43042, which lasted in the pool for less than 24 hours being swapped ICCP PM – IWCP LA – IWRP LA on the same day! 43141/142/144-148 were Old Oak Common based whilst allocated to West Coast duties. The Old Oak Common allocation was moved back to Laira on 5th April 1993 and the only non IWCP power car based at Old Oak (43140) was also transferred out, leaving Old Oak without an allocation for the first time. The six power cars in IWCP were transferred back to the IWRP pool on 19th April 1993 leaving West Coast with no allocated power cars, a situation which reflected the common user policy in force.

Following the completion of ECML electrification the East Coast was left with 11 HST sets and Power Cars 43038/039/095/096/104-122/153/155 all based at Neville Hill depot. Neville Hill also had 31 power cars (43043-061/064/066/072-077/081-083/085) allocated to IMLP for Midland Mainline services. Bounds Green had lost its allocation, as the entire fleet of Class 91s and Mark 4s were based there and Heaton was downgraded to minor fuelling and servicing for InterCity, as it became a Regional Railways depot. Improved Class 91 availability saw one set and power cars 43122/153/155 released to the Western region in May 1992, and following the demise of the through services from London to Lincoln and Cleethorpes in 1993, 43121 moved across to Cross Country duties which left the IECP fleet with 9 sets and 21 power cars. 43104 was later swapped with 43167 which had come out of storage with a trial fitting of a newer engine type and after a brief spell with Cross Country 43104 was placed into protracted storage. A further reorganisation of Cross Country diagrams during May 1992 saw a number of power cars transferred to Neville Hill for these duties, power cars 43086-089/101-103/121/122/155/156/180/198 all being reallocated from the Western Region, whilst remaining in the ICCP fleet.

Sector Codes

At this point it is probably worth pointing out a little of the history of the pool (or Sector) codes. Whilst initially allocation was on a regional basis, the switch to business sector ownership of assets saw all power cars allocated to pools for use on specific sub-sector duties. Initially this was an accounting exercise, designed to ensure that each InterCity sub-sector had the correct allocation of costs, but later power cars were dedicated to specific sub-sectors and could not be used on other services unless a hire was agreed between the relevant sub-sectors. A good example of this is the small IWCP West Coast fleet that is discussed above. This pool was created to ensure that West Coast took a share of the costs of the Great Western HST fleet: although the IWCP power cars rarely worked out of Euston as the policy of sending any Great Western sets over continued as before. It was only really during 1993 that true dedication of power cars to duties, and the split that was made then can still be seen in HST allocations now. The reallocations during May 1993 were numerous, but basically a swap between Cross Country and Great Western fleets was made, probably to ensure that those power cars fitted with ATP equipment were allocated to the Great Western sub-sector.

Towards Privatisation 1993 – 1996

As the railway headed towards the impending privatisation process, there were some minor tweaks required by the Great Western sub-sector. It had been operating policy that the Great Western and West Coast ‘fleets’ were interchangeable up to that point: any Great Western power car could, in theory, work a West Coast service. In fact Great Western only had the IWRP fleet with which to furnish power cars for Euston to Holyhead services, as the IWCP pool had been disbanded in 1993. All this wouldn’t work under the plans for separate Great Western and West Coast Train Operating Companies, so a dedicated West Coast fleet had to be created. At the beginning of the summer timetable in 1995, the IWCP sub-sector was re-created and a dedicated pool of power cars (and trailers) was allocated to West Coast, namely: 43028/029/041/042/164-166. Obviously the sets had to be based on the West Coast route and so the power cars and trailers were reallocated to Longsight depot in Manchester.

During 1995 further services were added to the short-lived Waterloo Eurostar connection services. Great Western had already been operating a return Waterloo to Cardiff service with sponsorship from European Passenger Services since October 1994. From May 1995, Cross Country were contracted to run Edinburgh / Manchester to Waterloo and return. To allow this to happen, power cars 43006-008/178/184 were reallocated from ICCS at EC to ICCP at LA for these trains: the power cars had come to the end of their ‘tour of duty’ during the Central Door Lock installation project and the EC-based fleet was the last to be completed. The Cross Country operated trains were very peculiar in that only EPS tickets were valid on them and it was not unusual for Edinburgh bound trains to leave Doncaster with nobody but train crew onboard! At the end of May 1996, Great Western finished their involvement with the Eurostar link services and likewise, Cross Country finished at the beginning of January 1997. After a period of work on ECML peak services these power cars transferred to Great Western as part of a franchise commitment.

Meanwhile, Cross Country were trying to rationalise their main fleet prior to privatisation and at the May 1995 timetable changeover, took all the NL allocated ICCP power cars and reallocated them to ICCP LA or ICCS EC, namely 43086-089 to EC and 43101-103/121/122/155/156/198 to LA. Thus NL was left with IECP and IMLP power cars only, ending their XC allocation. Furthermore, on paper IMLP’s books were bolstered during October 1996 by the re-allocation from the Porterbrook off-lease pool (SBXL) of re-built crash victim 43180: the power car was nominally allocated to IMLP to receive a safety case, but in fact worked on any TOC that required a short term spot hire machine.