VTEC’s HSTs: life begins again at 40

Forty years ago, one of the most iconic trains to ever grace the UK rail network first entered service. Designed by British Rail’s technical centre at Derby, the Class 43 HST remains to this day the world’s fastest diesel fleet with a 125mph maximum operating speed. 

Much has already been written about the Class 43s’ technical prowess and longevity, given that all but three of the 197 power cars built between 1975 and 1982 are still in full service in 2016.

Yet a cash-strapped British Rail had actually conceived the HSTs as a temporary fix between its most powerful main line locomotives (the Deltic had a top speed of 100mph) and the wider rollout of electrification once funding could be secured at a later date.

The trains’ launch in October 1976 under the InterCity brand was accompanied by a memorable marketing campaign heralding that the ‘age of the train’ had arrived for passengers, and that they would benefit from the reduced journey times afforded by the faster power cars, and from the superior levels of comfort that could be enjoyed in the newly-built air-conditioned and spacious Mk 3 coaches. 

In the post-privatisation era, that age is still here for a number of operators - including Great Western Railway (GWR) and East Midlands Trains (EMT), for whom the HST remains a key part of their fleets until electrification and new trains are finally delivered on these arterial routes out of London within the next decade.

Electrification duly arrived on the East Coast Main Line between London and Edinburgh by 1991, along with a new fleet of 30 Class 91 electric trains. However, current operator Virgin Trains East Coast retains 15 HSTs (30 power cars plus two in reserve) to serve its routes ‘off the wires’ between King’s Cross and far-flung destinations including Aberdeen, Inverness, Lincoln, Hull and Harrogate. Grand Central, CrossCountry and Network Rail lease the remaining HSTs. 

The prototype HST 41001, delivered in 1972, is owned by the National Railway Museum and managed by the 125 Group, and is currently based at the Great Central Railway (Nottingham). 

Unsurprisingly the fleet has required a great deal of technical and cosmetic improvement over the years to keep it running an intensive, high-speed service, and to offer an acceptable standard of travel for today’s passengers. 

By the turn of the century HST power cars had begun to develop an unwanted reputation for mechanical failure, and their original Paxman Valenta engines - renowned for bellowing thick smoke during acceleration and scaring small children with their high-pitched screaming noise - had to go. These have now been replaced by quieter and more fuel-efficient MTU 4000 series engines in all the ‘43s’, bar the 24 power cars leased by EMT that are equipped with Paxman VP185s.  

Between 2001 and 2006, GNER (then operator of trains along the ECML) embarked on its ‘Project Mallard’ to fit new interiors into its entire fleet of Class 91s and Class 43s. Other HST operators have followed suit, and a year later First Great Western updated its fleet of 52 HSTs and 400 carriages with new interiors and power sockets at Bombardier in Derby. WiFi is now also available throughout. 

After taking over the East Coast franchise in March 2015, it is now the turn of Virgin Trains East Coast (VTEC) to spruce up its ageing HSTs, as part of Project 21. 

Announced in November 2015, the project entails £21 million being spent on VTEC’s 30 Class 91 sets and 15 HSTs, to overhaul all 401 carriages and introduce Virgin Trains brand colours. Of that £21m, £4.5m has been allocated to exclusively refurbishing the HSTs. VTEC has also announced it is spending £16m on a separate project to re-engine all its HST power cars, now that the newer MTU engines have reached the 50,000-hour overhaul mark. 

This is potentially a landmark occasion in the illustrious story of the HST, and could prove to be the last major refurbishment undertaken by an operator before these trains reach the end of their lives. 

That’s because their future beyond 2020 is largely unknown. By that time both VTEC and GWR will have dispensed with the HST in favour of Hitachi’s Super Express Trains that are being delivered under the Department for Transport’s £6 billion Intercity Express Programme (IEP). 

ScotRail has committed to taking 27 HSTs from 2017/18, leaving the remaining 47 currently leased by GWR and VTEC unaccounted for. EMT will dispense with its HSTs at a later date, now that Network Rail has committed to electrifying the Midland Main Line. 

There is little doubt that mechanically the HSTs will continue to be in serviceable condition, and could still offer many more years of productive service for other operators. However, considerable expense will be required to make all sets compliant with PRM-TSI (Persons of Reduced Mobility - Technical Standard for Interoperability) regulations by the start of 2020. This will require the fitting of power doors to replace existing slam doors, universal toilets, passenger information systems and call-for-aid alarms. Wheelchair spaces are also required, as well as the conversion of existing toilets to controlled emissions toilets, to bring the vehicles fully up-to-date.