Old London Underground trains will be turned into diesel-electrics to operate on rural rail routes in a money-saving idea to replace ageing, uncomfortable trains.
Provincial rail passengers rattling through the countryside in crude, hard riding Pacer trains might not realise that these thirty-something vehicles were developed from the 1970s Leyland National bus.
Finding cost effective replacements has proved a headache for their operators, but now rail entrepreneur Adrian Shooter is planning to create a fleet of 75 Pacer substitutes by re-cycling soon-to-be-redundant London Underground District Line trains. These 30-35-year old, full sized D78 ‘surface stock’ electric multiple units had previously been earmarked for scrap. In January (2015) London Underground began replacing them with more examples of its air-conditioned, walk through ‘S Stock’ trains, which already work the Metropolitan, Hammersmith & City and Circle Lines.
‘I’ve had this idea for about three years,’ says Shooter, a mechanical engineer by training, with nearly fifty years experience in rail, most notably as managing director and chairman of Chiltern Railways.
He’s formed a company called Vivarail, which will transform electric urban trains that take power from third rails into rural diesel electrics, using 3.2 litre, 5-cylinder, 200bhp Ford ‘Duratorq’ diesel light commercial vehicle power units to drive generators, which in turn will power the train’s existing traction motors.
But why replace one lot of 1980s rolling stock with another?

’Nobody is keen to build these assets with a book life of thirty odd years
Adrian Shooter, Vivarail
According to Shooter, longer term plans to electrify lines make buying new commuter diesels at more than £2m per coach unappealing, when they might be redundant within a decade. ‘Nobody is keen to build these assets with a book life of thirty odd years,’ he says.
This leaves a short to mid term rail procurement gap, as some existing trains are in need of imminent replacement. A school friend of Shooter’s, who was the D78’s original project manager (it was one of the last trains to be designed in house by London Underground), mentioned to him that bodily, the stock’s alloy carriages were in good, corrosion free fettle. These units also had a design life that would originally have seen them running in the Capital until around 2030, but London Underground’s wish to standardize its big train fleet, increase traction voltage and operate trains compatible with new signaling and driverless control systems, meant the D78s were instead exiting early.
This was also despite their having new, costly bogies fitted a decade ago (the legacy of the wobbliness of the Underground’s intensively used tracks damaging the old ones), and a programme of interior improvements that finished in 2008.
‘We thought we could produce a rather interesting, modern train, which without new bogies and bodies would reduce costs and the carbon footprint of building new units,’ says Shooter.
This has led to some creative design ideas. A Brentwood based firm called Revolve Technologies, which adapts Ford passenger vehicle engines for other uses, is developing a cage containing a Duratorq engine, compressor for the train’s braking and sliding door and some switching systems, and an alternator, that can be slung beneath a D78 driving car’s underframe. The engines don’t need to be canted sideways, so there’s no issue over uneven cylinder bore wear.
‘It’s not immediately obvious if you look at the side of the train, but the space behind the longitudinal members (of the under frame) is quite deep,’ says Shooter. ‘We can go in from the side and lift everything eight or nine inches. We are confident that it will all fit.’

Shooter thinks that being able to quickly remove these units with a train in a basic or temporary building on its regular branch line, rather than being sent away for maintenance, has money saving potential for operators.
A driving car (the one with the cab end) will have two of these units, each outputting 750volts DC to power the traction motors. The diesels will have a stop/start facility and employ ECUs to allow them to power the alternators and, when needed, ancillaries such as the heating, but can be shut down when the train is coasting or stationary. Shooter thinks the diesel motors will have a 2-3 year operating life (‘we won’t know until we’ve tried them’), and that one way to prolong their life is to run them if sensors detect they’ve become too cold, which being in a largely exposed position is a distinct possibility.

The D78’s current electro mechanical switchgear motor control systems are robust, but require specialist maintenance, so Dutch firm Strukton Rail (correct) is supplying solid-state units to replace them. These should also be more efficient.
With rheosatic braking (where the train motors are responsible for much of the retardation) there is potential for electricity generation from regenerative braking, employing either battery or flywheel storage. Shooter says this is a couple of years away, and given the project’s tight schedule (the first prototype should be running this summer, conversions to two, three and four carriage diesel electrics are set for December (2015)) won’t feature initially.
Some branch lines have 75mph speed limits, but D78s won’t get above 60. Shooter claims a good power to weight ratio (the driving motor cars weigh 28 tonnes, compared to 35-45 for a new diesel equivalent) and better acceleration than, say the Pacers, will even things out and help overall journey times.

Cabs will be strengthened for crash worthiness, to protect the driver if the train ‘hits a tractor on a level crossing,’ something that hasn’t been an issue between Upminster and Ealing Broadway. Carriages will be connected by proper gangways and a variety of interior configurations, from a mildly modified version of the existing furnishings, to new internal architecture and toilets, are being designed.
The project is based at a former army railway complex at Long Marston, Warwickshire, which has a train test track, and has previously been used to store old trains nobody wanted rather than creating new ones.
Adrian Shooter thinks his born again ex-Underground trains could last for another twenty years, and although he politely dodges questions about how much they’re costing, reckons they’ll have easily paid for themselves in ten.
Vivarail’s ‘D trains’ are likely to be more congenial than the Pacers, but whether passengers will care that they’re also quietly innovative, remains to be seen.
Some rural stations don’t have toilets. Tube trains don’t have toilets. Will these converted trains have toilets ?
VivaRail does offer accessible toilets according to their website.
“Carriages will be connected by proper gangways and a variety of interior configurations, from a mildly modified version of the existing furnishings, to new internal architecture and toilets, are being designed.”
Evidently there will be toilets.
Inadequate ”toilets” on many trains:- Imagine the plight of the lady depicted in this article (below), with mainline trains running ?3m above her garden, right at the end of it. .. Let’s have some brilliant ideas, sewage/sanitary engineers for retro-fit. . .
“Susan Lea, from Shotton in Flintshire, has a railway line at the bottom of her property, and has had toilet waste from a train blown into her garden. “[It was] all over my washing, all over the garden, all over the fence, all over the chairs, all over the floor, it was everywhere.
“They wrote to me and told me that they’re allowed to drop this sewerage – it’s not fair on people older, like me, who have to clear it up ‘’’.”
“Seb Gordon, from RDG, told the BBC’s Inside Out West Midlands: “The rail safety board, the rail safety organisation, has looked into [waste from trains] and has found that it’s a relatively low risk.”…Oh, yeh??
What a great example of “Engineers doing for 10p what any fool can do for £1.00” There must be many other examples within society: what is required is a change of mind-set: to the concept of re-use and repair rather than scrap it!
All toilets on trains entering service today have to be Controlled Emission and do not flush onto tracks, and that will apply to the Vivarail units as well. Only older trains are allowed to flush onto tracks and they will all either be scrapped or converted to CET by 2020.
It is true that the D78 stock is a very successful design, and still gives good service. It would be a waste to scrap them so short of their service lives, especially since they were refurbished extensively so recently.
I was thinking though that, if they are converted to diesel-electric operation, there are some railway lines closer to London they may be suitable for; namely the Overground line from Gospel Oak to Barking, the Paddington to Greenford service, and the Southern line from East Croydon to Uckfield. These are lines where the D trains could operate with much fewer conversions than if they are sent to country lines. Their interior layout would not need to be changed for suburban use, and the four doors per side could be retained, and no toilets would be needed. Thus, the Turbostars currently employed on these lines could be released for other country lines, to which they may be better suited. Even if converted to diesel or diesel-electric, a D78 stock train could operate on the GoBLin with no modifications to its interior at all; save for the notices. Air conditioning could also be retrofitted if so desired.
It would be great if D-trains could be adapted for 3rd rail pickup so they could be used to take the “Borderlands” service into central Liverpool. If Merseyrail’s data is correct, eliminating the need to change trains at Bidston might increase usage five or tenfold.
I suspect this could be done as the platform is very flexible in terms of the powertrain type.