pdeaves
Established Member
Here http://www.railwaycodes.org.uk/misc/telegraph.shtm for those interested.@pdeaves excellent website has a section on all the codes (known)
Here http://www.railwaycodes.org.uk/misc/telegraph.shtm for those interested.@pdeaves excellent website has a section on all the codes (known)
Because the warning board, and therefore braking point for the speed restriction is placed at a distance from the restriction where reasonable braking can achieve the required speed. Why have 3 restrictions when just 1 will do? There is sufficient signage and paperwork out there already, why add more to the mix?I do not work in the industry, but if a speed restriction is imposed going from 125 to 20 mph, why are there not staged slowing down speed restrictions further back up the track? i.e. 2 miles back the speed reduces to 80mph, 1 mile back it reduces to 40 mph, so that when approaching the 'danger area', you are able to slow to 20 mph.
Exactly. All acronyms have to mean something at some point. Without something official, rather than a 2 bit website to say so, I'll stick with rulebook definitions too.Just because they might have started out as backronyms, doesn’t mean they can’t officially be adopted. As far as I am concerned, if they are on official literature then they are pretty much official...any thing else is just splitting hairs.
But again as I asked earlier with such a massive speed drop at short notice why was a message not issued over GSMR? The technology is there why isn't it being used effectively?Because the warning board, and therefore braking point for the speed restriction is placed at a distance from the restriction where reasonable braking can achieve the required speed. Why have 3 restrictions when just 1 will do? There is sufficient signage and paperwork out there already, why add more to the mix?
Exactly. All acronyms have to mean something at some point. Without something official, rather than a 2 bit website to say so, I'll stick with rulebook definitions too.
That, I don't know, and agree that a gsmr broadcast would have been pertinent.But again as I asked earlier with such a massive speed drop at short notice why was a message not issued over GSMR? The technology is there why isn't it being used effectively?
Also each speed board means someone going trackside which is a safety risk. There's little point in sending someone to several extra places unless there's a significant safety benefit. The way the braking curves work, the train will probably overspeed the restriction if the first board isn't acted on even if they brake at any extra one between it and the start of the restriction.Because the warning board, and therefore braking point for the speed restriction is placed at a distance from the restriction where reasonable braking can achieve the required speed. Why have 3 restrictions when just 1 will do? There is sufficient signage and paperwork out there already, why add more to the mix?
Not necessarily, going back to telegram days (which it does) it was just a convenient short word to use. Telegrams were charged by the word, so a whole series of internal code words arose. "Vice" for 'instead of', "Arrow" for 'send this message forward', etc. They had to be proper dictionary words, and were also selected so similarly-sounding/spelt words were not used, which limited the choice. The old GWR named all their various pw department equipment after fish, which is where "Dogfish" and "Bloater" as wagon types comes from. Less chargeable words than '20 ton pw department ballast wagon'.Out of interest, if SPATE doesn’t stand for anything, why was it used? There must be a reason that combination of letters was chosen.
The problem is then you have to base everything around the train with the worst braking performance. So if you base it on freight braking, then passenger trains will be delayed unnecessarily by slowing down too early.I do not work in the industry, but if a speed restriction is imposed going from 125 to 20 mph, why are there not staged slowing down speed restrictions further back up the track? i.e. 2 miles back the speed reduces to 80mph, 1 mile back it reduces to 40 mph, so that when approaching the 'danger area', you are able to slow to 20 mph.
But again as I asked earlier with such a massive speed drop at short notice why was a message not issued over GSMR? The technology is there why isn't it being used effectively?
Para 102: On 25 March 2019 an incident occurred which prompted an ad-hoc trial of a method of advising drivers by radio of an emergency speed restriction on the route ahead. A 5 mph (8 km/h) emergency speed restriction was imposed at Bushbury Junction, West Midlands, due to a crack in the stock rail of a switch diamond. A watchman was put in place, and in the space of 24 hours, three trains, from different train operating companies, exceeded the emergency speed restriction by a substantial margin. After the second case of overspeeding, Network Rail managers became concerned that any further instances could have serious consequences. After confirming that the emergency speed restriction signage was set up correctly, Network Rail decided that an additional mitigation was required to prevent overspeeding. A recorded message was broadcast to drivers of trains approaching the area over the GSM-R radio system, which is used to communicate between signallers and train drivers. However, a third overspeeding incident then occurred. The driver of this train reported misunderstanding the recorded message, and being confused about the exact location of the emergency speed restriction. The broadcast messages were subsequently suspended. Network Rail is considering the lessons from this incident.
You really want something failsafe, and this would be dependent on someone, probably with loads of other things to do, having to remember this for every train at the correct moment,But again as I asked earlier with such a massive speed drop at short notice why was a message not issued over GSMR? The technology is there why isn't it being used effectively?
The broadcast is automatically issued once set up if I recall? I'm sure there was one done for some issue or the other near New Cross. If the driver acknowledged the message correctly the signal cleared, if they didn't the signal was kept at danger and signaller contacted the driver verbally.You really want something failsafe, and this would be dependent on someone, probably with loads of other things to do, having to remember this for every train at the correct moment,
You really want something failsafe, and this would be dependent on someone, probably with loads of other things to do, having to remember this for every train at the correct moment,
The broadcast is automatically issued once set up if I recall? I'm sure there was one done for some issue or the other near New Cross. If the driver acknowledged the message correctly the signal cleared, if they didn't the signal was kept at danger and signaller contacted the driver verbally.
Because the warning board, and therefore braking point for the speed restriction is placed at a distance from the restriction where reasonable braking can achieve the required speed. Why have 3 restrictions when just 1 will do? There is sufficient signage and paperwork out there already, why add more to the mix?
Could the signals show a single yellow aspect approachng the speed restriction to encourage trains to slow down?
Just because they might have started out as backronyms, doesn’t mean they can’t officially be adopted. As far as I am concerned, if they are on official literature then they are pretty much official...any thing else is just splitting hairs.
The broadcast is automatically issued once set up if I recall? I'm sure there was one done for some issue or the other near New Cross. If the driver acknowledged the message correctly the signal cleared, if they didn't the signal was kept at danger and signaller contacted the driver verbally.
The problem is then you have to base everything around the train with the worst braking performance. So if you base it on freight braking, then passenger trains will be delayed unnecessarily by slowing down too early.
It would need the GSM-R system to provide a feed into the interlocking, which would not clear the signal unless that feed was present (plus all the other conditions to clear the signal). That would be major modification to a safety-critical system to retrofit, somewhat less difficult for new but still introducing extra cost and another thing to go wrong.Pretty sure the broadcasts aren’t linked to the signals in that way? I’ve certainly only ever either heard a broadcast while running on proceed aspects, or been checked down to a red and instructed to call the box.
At least 50% of the time I’ve received GSMR broadcasts they’ve been of such poor quality that they’re impossible to understand, and I’ve ended up calling the box anyway.
Pretty sure the broadcasts aren’t linked to the signals in that way? I’ve certainly only ever either heard a broadcast while running on proceed aspects, or been checked down to a red and instructed to call the box.
At least 50% of the time I’ve received GSMR broadcasts they’ve been of such poor quality that they’re impossible to understand, and I’ve ended up calling the box anyway.
Depends - some speed restrictions only apply to passenger trains or freight trains (as was originally the case in this incident, and one of the factors that led to it). Not beyond the realms of possibility to create separate warning boards for freight and passenger trains.
They exist and were used in this incident.
They are linked to the Track Circuit (berth triggered) I belive they can also be linked to a specific cell and even triggered to play at specific time intervals too.
If I'm reading it correctly the signage that distinguished the two was changed from freight to freight + passenger with minimal fanfare and no WON / depot notices, and that's where the confusion came from?
Here http://www.railwaycodes.org.uk/misc/telegraph.shtm for those interested.
Just for info, I have updated the page to (hopefully) draw that out better.Just because they might have started out as backronyms, doesn’t mean they can’t officially be adopted.
Still not proof.Just for info, I have updated the page to (hopefully) draw that out better.
*Although often it seems this is what the SG button does.
As soon as you hit it, the signal instantly changes to green .
Just for info, I have updated the page to (hopefully) draw that out better.