SSR Resignalling

Forgotten to post this observation from weeks ago.

If you’re heading west from King’s X especially during peak times, any train that re-gen brakes over the scissors crossover and section gap switches the tunnel lights on. I believe there was a similar instance down the Northern line pre ATO?

I would have thought that might make things difficult getting into or out of the depot.

Fixed for my favourite pedant

As painful as it is, it's all part of the commissioning progress. Whilst they may not necessarily seem it at face value, things *are* improving, albeit slowly, as staff get to grips with new processes. There was a similarly painful period when the first section went live, but fewer people became aware of it. As Met and District drivers get used to things the issues should die down.

...that said, I'm still in ticket for Edgware Road if anyone wants to re-open it. ;-)

Don’t hold your breath with Tower Hill working from day 1 100% there is still issues with 9a points which don’t help as trains don’t currently run on them.

I agree - it’s a bit cheeky to lay any blame on drivers for taking extra time to complete procedures within the CBTC area. Especially in the specific case of the RM procedure.

From a drivers point of view, the RM procedure is exactly the same as passing a semi automatic signal remaining at danger. If anything, from a driver’s point of view it’s a quicker procedure to complete as we can go back to full speed (ie, PM or auto) earlier than on the legacy system (where we have to pass another two signals showing a clear aspect).

Edit to add: I’m certainly not aware of a particular issue with driver errors being a problem anyway.

Because of movements in SMA go live dates, the vast majority of drivers now working in CBTC area’s have completed at least two refresher courses in addition to their original training course. A good number have done the refresher three times.

Whilst I’ll grant you not many drivers will have experienced degraded conditions for real (CBTC has generally been quite reliable), they will have practiced all likely scenarios a number of times in the simulator and are therefore well versed in what to do.

The main issues are trains stopping communicating which seems to be an issue with trackside aerial placement in some locations, or tripcock relays failing to latch over correctly at boundaries. From the drivers point of view, the resolution to both is to proceed using the RM procedure (either because there is no train maintainer to force the relay over or to re-enter the train into the CBTC system)......so there should be no difficulty in knowing what to do.

There has been issues with the CBTC system detecting movement when drivers carry out their brake test at Hammersmith sidings. If done correctly, that shouldn’t happen. It could be driver error but none of us are there when the brake tests are done so we can’t pass authoritative comment on that.

On the whole, there isn’t a lot drivers can get wrong as most procedures start with acting on service control’s instructions and generally end up with carrying out the RM procedure. From the drivers point of view, it’s not a difficult system.

I don't think it's necessarily 'gaps' in the trackside aerial placement, or at least not in the sense that fewer than should be needed were installed. It's more a case of the coverage of some aerials being less or at least different to that predicted. Radio frequency coverage is not always simple and dead/weak spots can be sometimes caused by all manner of things, and interference patterns can be incredibly complicated.

I am not sure there is much to be gained debating semantics. It seems that some drivers are aware that there are places where the existing aerials are not being picked up. At least in my book that sounds very much like a "gap" to me - even if it is an unintentional one.

From a passengers point of view there is nothing to be gained whilst contractors, TFL and any other interested parties argue over how it came about. Given the disruption these "gaps" are currently causing, passengers just want someone to go to each of these seemingly "known problem areas dead spots or whatever you want to call them" and figure how to fix them asap.

If it is just as simple as adding a few extra aerials, it is surely something they could fix in a few days. If after that the bean counters want to play the "pass the invoice game" fine, but please just get on with fixing it first, and argue over who pays later.

Physically adding them wouldn’t be an issue it’s just a post into the ground or a fixing into a tunnel wall.

Actually adding them onto the system is a whole new problem as each is numbered and is tracked by the system the whole software would need to be re written to allow the new antennas to be seen and tracked

Difficult to get an idea of the size of these things, but at the October LURS meeting Kasper Dixon said that the smaller tunnel antenna are mounted on a fixing that could hold a Mini -Cooper car!

Thales do lots of radio surveys on a regular basis. They have a receiver mounted to a track trolley and work out where to put the antennas.

Even in a non commissioned area the trains are still talking to the system but it’s physically not commanding the train these are just handshakes between the train and Hammersmith via the local sites

Which of course is where line controllers earn their money. The reversing berth is the responsibility of the District controller, they’ll know if two trains are likely to clash, and avoid it.

If your referring to Tower Hill then you won't be able to go from the current westbound platform back eastbound