Page 1 of 1
| Unlit signal 24/02/2023 at 08:44 #150634 | |
Dick
387 posts |
Just wondering why the signal in advance of an unlit signal should show a red aspect when if the signal was lit at red it would show a yellow aspect. How is an unlit signal any more restrictive than a red aspect? I'm sure there is a simple answer.
Log in to reply |
| Unlit signal 24/02/2023 at 08:49 #150635 | |
headshot119
4869 posts |
There's the inherent risk that the driver fails to sight the unlit signal especially in poor visibility and inadvertently passes it unlit.
"Passengers for New Lane, should be seated in the rear coach of the train " - Opinions are my own and not those of my employer Log in to reply The following user said thank you: Dick |
| Unlit signal 24/02/2023 at 08:52 #150636 | |
TUT
532 posts |
Do you mean the signal in rear? Well obviously because if it's unlit it's not displaying anything at all so there's a good chance that the driver won't see the signal and will just go right past it, particularly at night. Yes you are supposed to know roughly where your signals are and you should be expecting them, but there must be thousands of signals on the routes a typical driver signs and at night or in low visibility you've got nothing at all really. So, particularly if the driver hasn't been told, it's clearly an extremely dangerous situation which is why the signal in rear is held at danger and the driver needs to be told Log in to reply |
| Unlit signal 24/02/2023 at 08:53 #150637 | |
9pN1SEAp
1180 posts |
As it’s perfectly possible for a driver to see a yellow aspect followed by green, eg if the train in front is on a slow turnout, it forces the driver to stop and be told about the situation in order to avoid them not seeing the failed signal. As there’s no way to indicate if the failed signal is clear or not in normal running, the driver MUST proceed carefully to the sighting point of the failed signal and then contact the signaller again. You cannot assume that a driver seeing caution would stop at the next signal, if it were blank!
Jamie S (JAMS) Log in to reply The following user said thank you: Dick |
| Unlit signal 24/02/2023 at 08:58 #150638 | |
|
Dick
387 posts |
I knew there would be a simple answer, thanks. Yes I meant in rear, although it is 'before' the signal in question hence confusing rear and advance.
Log in to reply |
| Unlit signal 24/02/2023 at 09:43 #150640 | |
jc92
3685 posts |
TUT in post 150636 said:Do you mean the signal in rear?I think its safe to say the history books are littered with accident reports where unlit distant and stop signals have been missed by experienced drivers with inevitably disastrous consequences. Incidentally, beyond the technical restriction, its also a rulebook requirement anyway to stop a driver at the previous signal and advise of any defective signal (right or wrong side failure) in advance before proceeding. more applicable to absolute block signalling in a mechanical area where lamp proving doesn't necessarily lock the previous signal at danger. "We don't stop camborne wednesdays" Log in to reply |
| Unlit signal 24/02/2023 at 12:09 #150645 | |
|
clive
2789 posts |
It used to be acceptable to have "lamp or controls" - for all I know, there are still places where it is. That is, if a signal is unlit but would be showing yellow or better, the signal in rear was allowed to show yellow since there is almost no risk from the driver passing the unlit signal. I recall someone writing that, back in the 1960s, it was possible for a train to get a single yellow on the platform starter with unlit signals all the way to the buffer stop at Manchester Piccadilly if the routes were set all the way through. Dick: the way to think of "rear" and "advance" is from the viewpoint of a driver at a signal. The one in advance is the one they can see in advance of their train. The one in rear is the one that's behind the rear of the train. Log in to reply The following user said thank you: Dick |