With the forthcoming modular resignalling between Gresty Lane and Crewe Bank ( Shrewsbury ) by early Jan 2012 a dvd like the one in Ely to Norwich signalling would be a good idea for someone to film this as time is running out on these manual boxes and once gone no dvd or little photos to cherish for the history books.

I already have photos of the Shrewsbury boxes, along with Wem, Prees, Whitchurch and Wrenbury. No interiors for any of them though. Crewe Bank is nothing special (merely a concrete box).

Dave

DaveHarries wrote:
To be honest, most western European countries already have big, regional signal boxes. I can't see it is all worse here as it is in the UK.
It is a shame the mechanical boxes will disappear, as well of the older stile signalpanels. But you'd have to admit that it is not very practical to have boxes with 4 or 5 levers on a stretch of track with 1 or 2 trains an hour which need 3 persons a day to operate. In fact, I find it amazing such boxes still exist in a country like the UK.

what we must remember is that modernization has given a major boost into what can be done now compared to many years ago

There is a phrase, "putting all your eggs in one basket", which could apply here - except that 14 centres in the UK isn't exactly overdoing it. I've been fortunate enough to visit a couple of dispatching centres in the US which had opposite philosophies with distribution or centralisation of dispatching.

Firstly, the BNSF one in Fort Worth, TX controls the vast majority of their trackage in the US. In this case virtually everything that moves on the rails relies on this megacentre being online all the time. Yes, the building is supposed to be hurricane, bomb, and everything else proof.

Secondly, a Norfolk Southern one in Fort Wayne, Indiana (purely a coincidence with similar names!) which is one of several controlling NS trackage. I vaguely recall being told this one controlled about a fifth of their trackage. From there they theoretically have the option of taking control of an adjacent centre should that centre have to be evacuated.

Is one better over another? Probably a debate with no conclusion.

My point about "putting all your eggs in one basket" is this. Lets take East Anglia for an example. In Summer 2012 the Ely - Norwich line is to be resignalled with control being assigned to Cambridge in place of the boxes at Shippea Hill, Lakenheath, Brandon, Thetford, Harling Road, Eccles Road, Attleborough, Spooner Row and Wymondham South Junction: these boxes will all be abolished and, with perhaps the exception of a couple, later demolished.

I had a very pleasant trip on 09th July this year after Network Rail's AOM for East Anglia gave me a signalbox visit permit for Dullingham, Attleborough, Spooner Row, Eccles Road and Harling Road. Due to the fact that I decided to add a call to Kennett to get some exterior photos of the box there (I would never have got in: it was a Saturday and the box was switched out with all signals left at clear) I didn't do Spooner Row or Harling Road. So I got Dullingham, Kennett, Attleborough and Eccles Road done in the time I had. The signalmen I met were very friendly and the condition of the boxes (especially at Attleborough) was excellent. The signalmen were happy for me to take photos and, for the four calls made, I got 121 photos for my East Anglia signalbox collection.

The signalman at Dullingham told me (and this was confirmed by the duty signalman at Attleborough) that, although the control on the Ely - Norwich route will pass to Cambridge, it is planned for Cambridge PSB itself to close within a few years which will leave all of East Anglia under control of a new PSB at Romford, Essex. Here is where the "putting all your eggs in one basket" expression comes in: does it not occur to NR that, if this scheme comes in, a failure at Romford would quite probably paralyse all train movements in East Anglia? There would be no trains moving in such circumstances because there would be no local control left. Also, when it comes to locations for problems with trackside equipment, there is no substitute for local knowledge.

Dave

yes, I do see that. But because you only have 14 centres in the country it becomes viable to build a 15th spare one. This box has the equipment to take over other (failed) boxes. Also, you can protect your signal boxes a bit cheaper and easier by installing 1, or even 2 fallback systems of the various components. But as Geoff said, you can try to limit your fall-out zone to an as small area as possible, or try to minimize the chance such an fall-out happens at all.

The slight problem you can have (and in fact this happened last year in Utrecht, the biggest railway station in the Netherlands) is that you have installed the back-up UPS in the same room as the main UPS. When your main system catches fire you instantly have to shut down all operations due to a sudden lack of power (how strange...).

Or, as with Cardiff earlier this year, the main power source fails and the kick-in of the backup one causes a power surge.

Dave

Or as with York on 26/03/11. So now we are into the risk management game. You have to decide how much extra cost you want to bear in the normal day-to-day operation as compared with the costs of a catastrophic situation. The sad fact is that when you count up the direct costs of a total wipeout for a number of hours to the business, they are less than the ongoing costs of keeping a distributed system going.

Eggs in 1 basket?

The whole of the UK upper airspace and all of the lower airspace around Stansted, Luton, Heathrow and Gatwick is controlled from a single control centre in Swanwick. There are long term plans for the whole of Europe including the UK to be controlled from Maastricht, however that's many years off.

If the worst case scenario happened and a meteor landed on Swanwick nothing would fly over the UK until the contingency plans were implemented. The ATC simulator suite at Whitley can be brought online and can take control of the airspace albeit with reduced capacity. It would take a while to get things up and running again, not least because you'd have lost 25% of your controllers but the infrastructure is there and ready to go.

Now, if the airways can cope with this risk then surely the railways can manage the risk sensibly?

On the railways there are fewer and fewer areas where you can take local control of the signalling. Prior to SSI all remote interlockings had a local control panel. This enabled a signaller to go to site and operate the signalling from the local panel in the event of a loss of the link with the Control Centre. Following the introduction of SSI, local panels are no longer installed so we could already face huge problems if a complete signalling centre was lost. (Particularly since station staff can no longer act as hand signallers and point operators).

All that the railway needs to do is to ensure that they have a suitable fall back facility to take control if the main centre was lost.

The way things currently are we could not move control of an SSI interlocking from one control centre to another without involving an awful lot of cable running and testing. My best guess is that you could probably cobble something together within a week. Until that time it's ticket working and point winding.


FF