Mal de Mare on the Northern (and Jubilee Line seats)

The Northern Line now has automatic trains operating between High Barnet, Mill Hill East and Highgate. I thought I would see how it is going. The first stage, between High Barnet and West Finchley, was introduced on 17 February (so-called Migration Area 1) and the rest on 22 June (Migration area 2), the week of my expedition. There are six stages in all with completion expected early next year (the programme is running early).

An important part of the line upgrade is an increase in train performance along the automatically operated sections, trains having been reprogrammed to accelerate at 1.24 m/s/s rather than the sluggish 0.9 m/s/s which is what is mandated along the rest of the line. As we got ready to leave Highgate going north expectations were high.

The first eight seconds were impressive. The rest of the Journey to Barnet was disappointing (including an unplanned change at Finchley Central because the train was diverted to Mill Hill East, no explanation given). Highgate to East Finchley is uphill. Everytime we reached top speed the motors cut out with the result speed rapidly dropped, whereupon motors cut in again; the cycle appeared to take about ten seconds. This process of being subjected to alternate left and right swaying forces was, to say the least, disconcerting and evoked in my mind the feeling of being in a ship ploughing through a rough sea. It wasn’t like that when the trains were driven manually. The speed limit on this section is 40 mph (17.9 m/s) so it should have taken 15 seconds at the very least to hit this speed. The oscillation began sooner, suggesting that a lower maximum speed was being adhered to, yet from the evidence there was nothing in front. It was a dismal journey to Finchley Central (maximum line speed 45 mph, about 20 m/s) and I would be amazed if train speed actually exceeded 30 mph, also with see-sawing effects, though less pronounced as the route is more level.

After changing trains at Finchley Central there was a lengthy trudge to High Barnet at a painfully slow rate even despite the exceedingly brisk initial acceleration. Platform occupation at Barnet (coupled with my studying the southbound service) indicated we could not possibly be following anything. At Barnet, I was heartily fed up with the train on which I had arrived, suspecting it might be faulty. I boarded another train south, also curiously slow. As I say the speed limit on this largely straight section (and built to main line standards) is 45 mph, or 20 m/s. If travelling at the limit (and why not?) it should therefore take exactly ten seconds to travel between successive kilometre posts, spaced at 200 metres. The fastest section I noted was 11 seconds, with most 12-14 seconds, ignoring station approaches and so on – this is around 32-38 mph. Intriguingly, enough people have videoed the West Finchley – Barnet section post-ATO for me to find some and view them, from which I can time speeds where kilometre posts can be seen. On the whole these are exactly ten seconds apart – 45 MPH. What it should be. Perhaps I had travelled on an off day.

At this point I should mention that in automatic operation trains are no longer intended to coast, breaking with an exceedingly long tradition. This is intended to allow the train control system to alter target maximum speeds between stations to adjust journey times to optimize the service (ie to regulate the gaps between trains). This means that, instead of experienced drivers using judgement about the amount of coasting they do and allowing trains to reduce speed through coasting, having hit a maximum, the train now accelerates quickly to a target speed and tries to maintain it there. If that is what all the trains I was travelling on were doing then so much early running is surprising, especially having just left a terminus.

The final section into Highgate was torture on day of visit, mostly spent with short, sharp periods of braking along the steep downhill stretch. On departure from Highgate with the driver back in control, normality resumed with the train being professionally driven (you may recall that for some years I undertook train driver’s driving tests – I would not have passed a driver who was doing what the automatic system was doing, not without giving advice anyway).

What on earth is going on? This unsatisfactory type of operation cannot be solely the ATO system because it is similar to that on the Jubilee Line, which does not present these eccentricities, even on the gradients between Baker Street and Finchley Road. I would go as far as to say the Jubilee is a delight to use, with some reservations around current rail gaps where cars lose power during maximum acceleration which can make people fall over. Something on the Northern Line is different, and whatever it is needs fixing.

I gather from an informed source that others have noticed what I had noticed and also concluded it wasn’t right. My understanding is that the resignalling was designed in accordance with the PPP requirements where passenger comfort did not feature as a specific measurable, though discussions are now in hand about what can be done. I look forward to the next episode, but it surely cannot be left.

The poor old Northern Line desperately needs improved frequencies, deemed impossible to achieve without ATO. The sooner the better, but not at cost of basic passenger comfort. In addition, it must surely be time to reconsider some of the speed limits in the open air sections where there are few if any loading gauge restrictions and much is dead straight. 45 mph is a tad slow these days, and the fact that the trains accelerate so briskly and then power is cut out to maintain some historic limit just draws attention to it. The trains are itching to pull away and the constant reining back is a little frustrating!

Oh, and when I said the Jubilee Line was a delight to use, I exclude use of the seats. They were never ‘comfortable’ but at least started off as ‘OK’. It is now as though such cushioning as there once was has been replaced by a cloth-covered wooden board with absolutely no ‘give’ in it at all. Surely this cannot be intentional? The similar ones on the Northern seem to have retained their springiness without difficulty. Again, it is hard to think why rock-hard seats should be anyone’s aspiration (now far worse than even the Central Line seats), which suggests a maintenance issue perhaps? In the meantime do not sit down too hard on the Jubilee Line, if you are lucky enough to get a seat at all.

The next Northern Line Migration Area to switch to automatic will be Highgate and Chalk Farm to Euston (Charing Cross branch) and Angel, followed by the central area (both branches) to Oval. The fifth area will extend to Morden, and the last one will be Chalk Farm to Edgware. I am looking forward not so much to the automatic operation that will be introduced, however essential it is, but to the associated train control system that has to manage headways along so many different but intermixed services whilst trying to maintain parallel junction working at Camden Town and Kennington. If that works well, I will be impressed.

{See also update on 11 July}




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About machorne

I have always lived in London and taken a great interest in its history and ongoing development. This extended into the history of its transport services, about which I have written a number of books - I have spent most of my working life working in the industry and observing changes from within, mostly to the good, but not always so. I continue to write, and have a website with half finished stuff in it so that it is at least available, if not complete. Several new books are in hand. I have many 'works in progress' and some of these can be found on my website; the we address is http://www.metadyne.co.uk
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One Response to Mal de Mare on the Northern (and Jubilee Line seats)

  1. G. Tingey says:

    Speeds on the Central Line between Epping * Theydon or Debden or LOughton are considerably higher than 40 mph.
    SP why this snailing along, as well as the oscillations?
    Not good news

    Like

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