Neil Turner's Blog

Blogging about technology and randomness since 2002

D trains of Future Past

144 Crossing the River Calder
I’d like to introduce you to the ‘D Train’. If its manufacturer Vivarail gets its way, then a large number of these are destined for the north of England.

D is for District Line

The D Train is not a new train, and Vivarail are not train-builders in the traditional sense. They will be taking redundant London Underground electric trains, and converting them into diesel trains for use outside the capital. Specifically, the trains that will be converted are the D78 which operate on the District Line.

The ’78’ in D78 refers to when construction of these trains began in 1978, with the first trains commencing service in 1980. Whilst this was 35 years ago, they are not the oldest trains on London Underground’s network – the trains on the Piccadilly and Bakerloo Lines are older. Indeed these trains probably have 10-15 years of life left in them, and the bogies (the wheel sets that the carriages sit on) are relatively new. They’re being replaced earlier than normal to ensure that all of the so-called ‘sub-surface lines’ (the Circle, District, Hammersmith & City, and Metropolitan) all use a common type of train – the new S stock trains.

The S stock has also replaced the even older A stock on the Metropolitan Line, and the C stock on the Circle, Hammersmith & City and ‘Wimbleware’ Wimbledon-Edgware District Line services. Now it’s the turn of the D stock to be withdrawn.

One man’s scrap…

When the A and C stock were withdrawn, they went straight to the scrapyard – the earliest trains dating from the 1960s. But the D stock is newer, with some trains only refurbished as recently as 2008. Scrapping these serviceable trains would be a waste, and so London Underground sought buyers for the fleet. Vivarail was the successful bidder, and so as the D78 stock is withdrawn, the trains are taken to its workshops.

The main change is converting them to diesel trains. London Underground uses a four-rail DC electric system which is unique to London, so the traction system will be changed with new diesel engines added – in fact, the engines will be basically the same as those fitted to Ford Transit vans. They will retain their electric transmission, making them ‘diesel-electric multiple units’, a bit like the Voyagers used by Crosscountry and Virgin Trains.

Whilst similar third-rail electric systems are prevalent across the south-east of England and on Merseyside, there are plenty of new electric trains being built at the moment so there’s no real demand. At present, no manufacturer is building any new diesel trains for the UK market (Hitachi’s new class 800/801 trains for the Intercity Express Programme will have a diesel engine but they’re primarily electric trains). Whilst more railway lines are being electrified, these projects will take time with some lines not going live for another 5-6 years. Others probably won’t be electrified at all, as there’s no economic case to do so, and so diesel trains will still be needed in future.

A 2020 vision

January 1st 2020 will be something of a watershed for passenger rail travel in the UK. After this date, all passenger trains must be accessible to Persons of Reduced Mobility, which mandates wide doors, space for a wheelchair, a wheelchair-accessible toilet and digital displays showing information to passengers, amongst other things. We’re five years away from this deadline and yet there are hundreds of trains out there that aren’t compliant.

Most trains can be converted – but at a cost. And for some trains, the business case for conversion is weak or non-existent. This may be because of the amount of work required or the age of the train (or both).

The dreaded Pacer

If you live in the south-east of England, then you may never have encountered a Pacer before. These trains were built cheaply in the 1980s by bolting bus bodies onto freight wagons, as a short-term measure to cover for a shortfall in passenger trains. Whilst the oldest of these, the class 141, have been withdrawn from service, classes 142, 143 and 144 are still in revenue service across the north of England, Wales, and south-west England.

They’re not popular with passengers. Unlike most trains with bogies, these have two simple axles per carriage, which gives a much poorer ride quality, especially on older jointed track. Their cheap construction also raises questions about their crashworthiness. Politicians have claimed they will be withdrawn, but not given any timescales or firm commitments.

The leasing company that owns the 142 sets, Angel Trains, has already said that it won’t upgrade its trains in time for 2020, which means that they should be withdrawn by then. The 143 and 144s are owned by Porterbrook, who are developing plans for refurbishment where required.

Another unsuitable short-term stopgap?

The Pacers were a short-term stopgap in the 1980s, but ended up being used for far longer than intended. My worry is that the same thing will happen to the D Trains. Whilst they may only be planned to be in service for 10-15 years, history may repeat itself, with D Trains still running on passenger services beyond 2030 – by which time they’ll be past 50 years old.

The ride quality on the D Train should be better than on the Pacers, and they will have more carriages. Almost all Pacer units are two carriages which just a handful of three carriage trains in the north; D Train units will have three carriages as standard. Plus, they will have a completely new interior, and a new, modern front-end. They should feel like new trains, even though the body shells are already 35 years old.

The other major concern is their top speed. Despite their cheap construction, Pacer trains are capable of a top speed of 75 miles per hour, and newer diesel trains can reach 90 or 100 miles per hour. The D Train will be limited to 60 miles per hour – after all, they were originally designed for commuter services where a high top speed isn’t important.

There are currently plenty of lines which have a 60 miles per hour speed limit (or lower), so at first this shouldn’t be an issue. But Network Rail are working to increase speed limits in the north, especially on the Calder Valley Line that I use every day. HADRAG, the Halifax and District Rail Action Group (of which I am a member) is therefore against their use on this route as it would undermine Network Rail’s improvement works.

Hand-me-downs for the North, again

As well as the technical objections, there’s also the issue that these will be yet more old trains being sent to the north of England, whilst London and the south east gets new trains. In the north-west, Northern Rail are introducing Class 319 electric trains between Manchester and Liverpool in May, now that the line has been electrified. But these electric trains also date from the late 1980s and previously ran on the Thameslink services between Bedford and Brighton. They’ve become spare only because new trains are being introduced on the Thameslink route. And whilst Northern Rail are refurbishing them before they enter service, they won’t be as nice or modern as the brand new trains being introduced down south.

Brand new trains are more expensive, and will take longer to build. Converting the D78 stock into a D Train costs around 2/3rds of the price of an all-new train, and can be done much more quickly than building a new train from scratch. Vivarail is aiming to have a demonstrator train ready for the summer, so that the three companies bidding for the next Northern franchise can evaluate it.

Of course, it could be that none of the train companies are interested. There’s no guarantee that anyone will buy the D Train. But I would be surprised if the project failed. Vivarail was founded by Adrian Shooter, former chairman of Chiltern Railways and a rail industry veteran. I doubt he would have invested so much in this project if he expected it to fail.

And, on the whole, I think it’s a good idea. Scrapping old, but serviceable trains is ridiculous when there’s a need for extra rolling stock to prevent overcrowding. I would say that they are better than the worst trains that run in the north, even with their lower top speed (but better acceleration). But there are many lines where these trains will not be suitable, and so care needs to be taken to ensure that they are allocated to lines where they can make a positive difference to the service.

In an ideal world, the whole country would get new trains as and when required. But if that’s not on the cards, then any extra trains are better than none, I suppose. I just wish that the north of England would get a bigger share of the new shiny things.

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