Yes. Again, it is not like waving a mate out of a driveway.Is any of that applicable to a train that only needs to go back a little bit along a line it just came along legitimately?
Yes. Again, it is not like waving a mate out of a driveway.Is any of that applicable to a train that only needs to go back a little bit along a line it just came along legitimately?
Well no, because you don't have a bod controlling traffic lights stopping people driving by whilst you wave your mate out.Yes. Again, it is not like waving a mate out of a driveway.
That would be a risk assesment for the signaller/controller. "Do we need to risk a MOM trackside, or can we safely use a driver who is about to pass by the other way?"
Let's run the railway your way, and see how many people we can killWell no, because you don't have a bod controlling traffic lights stopping people driving by whilst you wave your mate out.
The delay attribution guide was ammended for this - it now reads that if the driver is unable to to stop at the junction signal safely it's only is he then passes another signal on the incorrect route that the incident would be split between the signaller and the driver.I can think of several locations where if a wrong route were offered, the Driver approaching it would have insufficient time/distance to bring their train to a stand at the signal upon first being made aware of the routing beyond it
It’s somewhat ironic that PRI’s were installed around ordsall lane, apart from where the approach speed was highest.The delay attribution guide was ammended for this - it now reads that if the driver is unable to to stop at the junction signal safely it's only is he then passes another signal on the incorrect route that the incident would be split between the signaller and the driver.
In the Manchester area we have definitely had trains approaching Ordsall Lane heading towards Manchester wrong routed by ARS and not be able stop at the junction in time.
A risk assessment done by someone who isn't on site. Who is responsible if things go wrong - the signaller/controller or the driver(s) who gave them the description of the situation?That would be a risk assesment for the signaller/controller. "Do we need to risk a MOM trackside, or can we safely use a driver who is about to pass by the other way?"
This is from publicly available information and has some gaps as a result. The freight train was from London Gateway to Hams Hall with signalling headcode 4M47.Anyone able to provide a summary of this incident?
Depending on the train detection system used (track circuit type or axle counter) for a controlled signal, the distance between the signal and the first axle of a train causing the train detection system to “show occupied” can be as little as 10cm. Obviously it could also be further, sometimes as much as a couple of metres.The train went far enough past the signal to trigger the berth step in the signalling system and lock the route without it being able to reset by the signaller. It's unclear exactly how far it went past though the photo in the original post suggests not very. After the issue was resolved the train then continued with an hour delay along the very short term plan route.
The booked WTT path for this service is via South Tottenham, then Willesden and WCML. Gospel Oak-Barking was closed yesterday so the schedule was amended to run NLL to Canonbury, then up the ECML. The amended schedule was then cancelled and a STP schedule created for NLL to Willesden, then WCML. So with 3 different schedules going 3 different routes, it is not surprising that confusion arose!
The usual route uses the Barking to Gospel Oak line which wasn't available due to engineering works. There were two schedules in place both using that headcode:
- An altered schedule from the usual process, RealTimeTrains link which was pathed at Canonbury to go to Finsbury Park and onwards up the ECML
- A very short term plan schedule (typically within 48 hours) RealTimeTrains link which was pathed at Canonbury onwards to Camden Road and up the WCML
Does that mean that drivers of locos where the cab is considerably more than 10cm, and maybe even 2 metres, behind the leading axle (37s etc, not to mention steam locomotives), see signals going to red in front of their eyes?Depending on the train detection system used (track circuit type or axle counter) for a controlled signal, the distance between the signal and the first axle of a train causing the train detection system to “show occupied” can be as little as 10cm. Obviously it could also be further, sometimes as much as a couple of metres.
Of course, in reality the first axle is not right at the front to the train, so the distance the train can travel is always slightly greater.
No, because the signals are not visible from the side.Does that mean that drivers of locos where the cab is considerably more than 10cm, and maybe even 2 metres, behind the leading axle (37s etc, not to mention steam locomotives), see signals going to red in front of their eyes?
How close do you get to a signal before it can't be seen from a cab?No, because the signals are not visible from the side.
I'm not sure on the exact numbers, but the usual standback distance is 20m. It will vary depending on where the signal is position relative to the drivers eyeline (Gantry, left/right etc) and what the visibility from the cab is like.How close do you get to a signal before it can't be seen from a cab?
Just googled the Flying Scotsman, which is apparently 70 feet long (21.6m) - which I think includes the tender, so 20m should be enough!I'm not sure on the exact numbers, but the usual standback distance is 20m. It will vary depending on where the signal is position relative to the drivers eyeline (Gantry, left/right etc) and what the visibility from the cab is like.
Yes, that length includes the tender (Flying Scotsman is rather snug on a 70' turntable).Just googled the Flying Scotsman, which is apparently 70 feet long (21.6m) - which I think includes the tender, so 20m should be enough!
Depends on the type of signal, its location and weather conditions.How close do you get to a signal before it can't be seen from a cab?
Some signals probably would go back before the cab reached the signal but it would only be noticeable at slow speed, and by that point the focus wouldn’t be on that signal anymore.Just googled the Flying Scotsman, which is apparently 70 feet long (21.6m) - which I think includes the tender, so 20m should be enough!
Because I am interested why it wont work, rather than just a "wont work".They won’t necessarily be familiar with the location on the ground…
You’ve been told several times by experienced and knowledgable posters why your suggestion won’t work, so why do you keep arguing?
But when people give you a list of the reasons why it won't work, you then just repeat you questions.Because I am interested why it wont work, rather than just a "wont work".
The railway has a very clear valuation of how much safety is worth. For sure, the railway is guilty of 'we've always done it this way', but quite often the proposals either create new risks or cost a large amount that doesn't justfiy the safety benefit.Its not like the railway doesn't have a habit for 'because we have always done it this way' and 'its safer' without an actual calculation of whether it is actually safer enough to justify it.
Because I am interested why it wont work, rather than just a "wont work".
Its not like the railway doesn't have a habit for 'because we have always done it this way' and 'its safer' without an actual calculation of whether it is actually safer enough to justify it.
For sure, the railway is guilty of 'we've always done it this way', but quite often the proposals either create new risks or cost a large amount that doesn't justfiy the safety benefit.
When the solution to Risk A creates a new Risk B you need to weigh up which risk is greater and then account for possible mitigations for Risk B, which in turn may introduce Risk C, and so that and its mitigations need to be factored in. Then you factor in that as Risk A no longer exists, a mitigation for that doesn't need to happen so Risk D can also eliminated, but then you need to check whether that mitigation is also mitigating against other risks and whether they still exist. All this can get very complicated very quickly, and all evaluation of risk involves some degree of subjectivity. For example, "the Fatal and Weighted Injuries Index gives a fatality 10 times the weight of a serious casualty, and a serious casualty 10 times the weight of a slight casualty" (according to the first source google found) so if procedure A has a risk of 1 serious casualty in a given time period and procedure B has a risk of 10 slight injuries in the same time period which is safer? If procedure A risks 1 broken arm and 1 broken leg in a 5 year period is that better or worse than procedure B which risks 2 broken arms but no broken legs in the same 5 years?The railway has a very clear valuation of how much safety is worth. For sure, the railway is guilty of 'we've always done it this way', but quite often the proposals either create new risks or cost a large amount that doesn't justfiy the safety benefit.
Two "worst case" scenarios that come to mind: a derailment if points move under the train. It would be low speed, but could still do quite a bit of damage. Or someone could get crushed by the train if the driver in the assisting train can't see them from the cab.So what's the worst case scenario in the Meerkat approach then?
It takes time for the signal to change the aspect it is displaying.Does that mean that drivers of locos where the cab is considerably more than 10cm, and maybe even 2 metres, behind the leading axle (37s etc, not to mention steam locomotives), see signals going to red in front of their eyes?
Points moving under the train is a non issue in respect of who is controlling the move at the back. If they can move, then they can move whether it’s another driver or someone else on the ground seeing back the move. Someone being crushed or struck if the rear driver hasn‘t got full view is fair, but it might surprise som people that propelling a train without anyone at the back is actually permitted in some circumstances.Two "worst case" scenarios that come to mind: a derailment if points move under the train. It would be low speed, but could still do quite a bit of damage. Or someone could get crushed by the train if the driver in the assisting train can't see them from the cab.
That is true. However someone on the ground is more likely to see/hear something than a driver up in a cab, possibly over an engine running and limited view back down the line.Points moving under the train is a non issue in respect of who is controlling the move at the back. If they can move, then they can move whether it’s another driver or someone else on the ground seeing back the move.
With respect, it’s very unlikely that motor points or mechanical points controlled from a signal box that have electric lever locks and track circuits would move under a train. Even without a signal route being called, track circuits and axle counters directly lock and hence prevent such points from moving under a train.Two "worst case" scenarios that come to mind: a derailment if points move under the train. It would be low speed, but could still do quite a bit of damage.