Re-engineered Tube train begins main-line diesel trials
A new diesel train has begun main-line testing this week. Vivarail’s class 230 prototype, which has the bodyshell of a former London Underground electric Tube train, is running between Tyseley and Leamington Spa in the West Midlands.
Initial tests have seen the train running at its full permitted speed of 60mph, which is not possible at the Long Marston test facility where it was built, as well as testing the integration of the braking systems. Tonight (December 1 2016) it will run with loads of 15 tonnes in each of its two cars to check that it can maintain its required braking distance when fully laden.
A third car is to be added soon, which will showcase interior layouts for suburban and longer-distance branch-line services. The first two vehicles retain the Underground’s high-density commuter layout.
As well as engineering tests, the programme includes driver training.
Vivarail has bought most of London Underground’s District Line D78 stock, which is being phased out, amounting to 228 cars. By reusing the bodyshells and bogies while replacing almost everything else, the company says it can produce economic, easily maintained diesel trains with a much shorter lead time than new vehicles and also offer passengers a good-quality experience.
The D78 bodies are of aluminium, so have not suffered from corrosion, while the original bogies were replaced ten years ago with a Bombardier unit that is still in production. As to the rest, Vivarail CEO Adrian Shooter, speaking last night at the IET Railway Lecture in London, said all the electrical systems have been replaced except the Westcode brake system, while for ease of maintenance “all the bits that might wear out” have been fitted into one of two modules: the bogies and the power module. The latter incorporates two 200hp Ford diesel engines with an alternator and rectifier and a compressor.
This module fits under the vehicle body and has quick-release connectors for air, electricity and diesel so it can easily be replaced. The aim is for this to be achievable in 10 minutes (replacements take “eight hours on most diesel multiple units” according to Shooter) but the development team have demonstrated a swap in just four minutes.
Vivarail has no firm orders yet for its re-engineered trains, but it is developing a version with a battery pack for an unnamed customer. That opens up the possibility of diesel hybrids or electric trains that could switch to battery mode for lines where continuous electrification is difficult, for example because of low bridges, or for running beyond the end of an electrified section. Shooter says the customer’s requirement is for seven miles “and we can do that easily”.
There have been widespread suggestions that the class 230 could be an economic replacement for the ageing and unpopular Pacer units that run on many rural and lightly used lines, particularly in the north of England, but a year ago the Department for Transport specified that the next Northern Rail and Trans-Pennine Express franchises should buy new trains instead.
However, Shooter said that when those franchises were being let, the train wasn’t ready. “At that time we didn’t have the credibility. Now, we’re demonstrating that it’s workable and the politicians and civil servants are being supportive.”
If all goes well with the test programme, the class 230 should be certified for passenger service early in 2017. Then the plan is for London Midland to run the prototype under trial on the Coventry to Nuneaton line.