2012 Q9 Handsignalling a layout after derailment
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2012 Q9 Handsignalling a layout after derailment
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[/i]Good afternoon,
I have attached an attempt at the above question for review. Any feedback would be appreciated. Regards, Neil 
06-09-2014, 12:30 PM
(05-09-2014, 02:45 PM)neil-thomson Wrote: Good afternoon, Some thoughts for you:- Not sure how long you would have spend writing what is here, but the number of words looks to be insufficient for the number of marks on offer. Your list of assumptions is a good idea because it is then clear what you are thinking when giving your answer. However, you need to be careful that your assumptions are reasonable. For instance, you have said "Further crossover from Down Fast to Down Slow available to the Down side of Station B" yet you have admitted at the end that the things show are shown for a reason and hence by implication, things that are not there are not available in this scenario. Also, you have assumed that the two routes from 719 are to different places than the two routes from 101 signal. I think that this is unlikely since 719 is not likely to have a route up to 427 and not have a route up to 209 (I think 429 is there for turn back moves rather than having a route up to it). Of course, I have assumed that you are following UK mainline practice when putting this comment (you have not said) and hence under this assertion, we know that 719 only has two routes because the SI has to show an indication for all routes, whereas if it is the practice of the railway authority you are following to give no indication for the "straight" route from the signal with the SI, you could be assuming that there are in fact three routes from 719, and your point would be valid. This is a long winded way of saying that you must tell the examiner all that they need to know to interpret your answer. You mention the tunnel from the perspective of staff safety, but I would expect there to have been some more discussion about the additional problems that operating degraded working through a tunnel. As you say, things are shown for a reason, so it is a good clue of areas to think about writing about. The question asks you to describe a safe method of working. In option 1, you have said which way the trains are going to go and have quoted the appointment of hand signallers, together with the importance of good communication, but you have not actually said how things would operate. I think it is insufficient in this circumstance just to say that you will use a hand signaller - the question is crying out for a description of how hand signalling works. In option 2, you have mentioned staff or ticket working - again, a description would not go amiss here and if there is this option, what are the relative risks of doing this hence giving you more things to list in your risks and mitigations section. One area that you would have got some credit is the thinking about how you might alternatively deal with the passengers who want to get off at B and having them go to A and travel back under normal signalling is perfectly valid. Overall, I think the examiner would be struggling here to give many marks for this attempt. Peter
07-09-2014, 04:04 PM
A reasonable attempt for what is a tricky problem to solve. A clear set of assumptions can certainly aid the answer overall. The examiners are just looking for a demonstration that a candidate understands how to approach safety and the effects of implimenting rules, human factors etc.
I would offer three options to the examiner. For me, two isn't sufficient. The assumption list is good but some of the assumptions should be limited to specific options. For me, there are three basic options: 1) low-risk - fully signalled moves, reduced service - capacity killer but safe! 2) medium-risk - reduced service, run down trains on the up fast, ups on the up slow - most fully signalled but a few people on the ground, reduced capacity. 3) high-risk - full service, run down trains on the up fast, ups on the up slow, keep branch open - most fully signalled but more people on the ground, very risky due to complexity of west junctions, the branch and bi-di moves (assuming branch reverses/terminates at B). Many clues in the text and diagram about what to watch for i.e. the tunnel. That makes any non-signalled moves far more risky as do turnbacks, crossings down trains across fast and vice versa. The route between 805b and 812a being particularly hazardous under rules based signalling. It would also be worth talking about duration for clearing the blockage. Longer periods require handovers, multiple rush-hours etc. Remember, M1 is about safety so don't get drawn into describing technical solutions. Signalled routes are safer by default. Large numbers of lineside people will put pressure on the signaller who has to control each of them individually and as a group. They won't be used to doing so and mistakes will occur. The tunnel will likely reduce the drivers' ability to spot an error and stop those on the ground from watch what the others are doing. There certainly is a basis for an answer but as Peter states, it would be difficult to give more than a few marks. Jerry
Le coureur
08-09-2014, 02:44 PM
Thanks gents. I must admit the routing assumptions were a boo boo on my part. I can claim that is was a misreading error from hand written notes to the typed version.
Jerry - for your first option - would there be fully signalled moves if no bi-di routes are available? Or is this the case that all Down direction trains would terminate at the preceding stations? Would it be fair to say that this would be a fail? I'm only asking so that I know how much more information I need to drive into the answers
08-09-2014, 08:22 PM
02-09-2015, 09:57 AM
Been looking at this question firstly if B is a busy mainline station would it not be appropiate to maintain the straight route C to A and bus substitute the branch as one solution? Or even maintain A to C and signal as normal and bus substitute C to A??
I would assume due to the lack of a JI at EF205 there is no natural route from EF205 to EF427 so trains would have to be authourised to pass EF205 at danger- (D notice or handsignaller)- with 805 and 812 collared reverse on the panel and stopped at EF427? I assume due to the POS 4 feather on EF101 a route is not available to EF427 to again degraded working and authorising of passing a signal at danger. I would assume the SI on EF719 giving a 2 would be for the down slow and down fast and a natural route does not exist between EF719 and EF427 so again if a service is required of the branch it would be degraded working- ( D noticed or handsignallers) I find EF427 confusing- a lack of a JI would suggest the lack of a route to the down fast, its a 3 aspect signal so I assume it leads to a bi-directional signal on the up slow?? Therefore trains brought into Platform 1 under degraded working would have to be authorised past a signal at danger under degraded working.
03-09-2015, 12:59 PM
(02-09-2015, 09:57 AM)StrongLifts5x5 Wrote: Been looking at this question firstly if B is a busy mainline station would it not be appropiate to maintain the straight route C to A and bus substitute the branch as one solution? Or even maintain A to C and signal as normal and bus substitute C to A?? Can someone look at this for me, I did it under exam conditions probably round 32 mins, loads more I could add but you only have so much time, all i'm looking is a pass :-)
03-09-2015, 01:13 PM
Not all the scan came out point (5) on my assumptions is 811 clipped and point (6) all other points set, locked and collared from the signal cabin
 (03-09-2015, 01:13 PM)StrongLifts5x5 Wrote: Not all the scan came out point (5) on my assumptions is 811 clipped and point (6) all other points set, locked and collared from the signal cabin Sorry for the delay- pressure of work, domestic life and many requests from multiple sources. Answer wasn't particularly easy to assimilate- you'd be better to have separated each numbered point by spare line of space! Item 1 was good, but items 2-4 too repetitive without adding much. Better to have addded these as 3 short sub bullets of the first.
Definitively should have had significant break before item 5; the examiner is still reading all your 15 items as ASSUMPTIONS because that is what it said above- wondering when you are going to get on to describe the methodology which actually starts at 5 but you have given no clue to this. Item 5. Not clear what you mean as 8 points; the point IDs are all 3 digit and I don't think you mean 808 as there are no such. Do you mean 8 separate point ends- if so which ones are these- LIST! Item 6. Without knowing item 5 then 6 is not itself understandable to the ones you think are working normally Clearly with the freight derailed in the area, traffic through the station will only be on the lower lines on the diagram- the question really is how you are going to use the Up Fast in the Down direction and at what site the trains regain their correct running lines. Also if a freight has derailed, presumably it was a signalled movement and therefore is likely to be holding the locking for those points in the remainder of its route so an assumption about which these are, what arrangement may be made procedurally to release that locking or to wind the points manually and secure (but without detection since their actual lie will be at variance to the interlocking set position) needs to be made and stated. Item 7. I am wondering whether this is back to being an assumption, or is describing how a signaller is helped to authorise verbally a train movement when route cannot be set and signal cleared Item 8. This definitely looks like an assumption and worth making, but I'd have added as sub bullet initially. Item 9. An assumption which I think is not worth stating explicitly- you do not have the luxury of the time Item 10. Is this assumption relevant at all; not only does it seem pretty obvious that it only reads to the Up Fast but given the derailment this is really not going to feature in the method of working being proposed. If of course you are postulating that this was the route in use when derailment occurred then yes it would be relevant as only the Up Slow would be operative after the incident. Item 11. Incorrect. EF417 only has one route and that must be to the Down Fast as the other lines not signalled in that direction. It is a set back move from platform 1 and clearly no confusion to driver so obviously been decided not to warrant a PLJI Item 12. Agreed- but whether worth stating as assumption I doubt Item 13. Agreed, but not really the essence of this question; again perhaps a sub-bullet in the first item Item 14. Really inherent in item 1 Item 15. Assumption well worth stating; the derailment could have done any amount of damage to the infrastructure affecting a far wider area. ----------------------------------------------------------------------------------------------------------------------------------- I realise that there are more sheets to your answer which I will look at later when I have time, I have now reversed my feeling earlier and decided ALL THESE WERE ASSUMPTIONS rather than starting to describe method of working. However you must have spent a quite significant part of your time allocation on these and that was too much; yes you need to state a few, but do get to the essence of the question more quickly and only list those that are needed for the examiner to understand the context of your answer. It is a balance and actually because you have listed some that I think are INCORRECT then it may help the examiner understand why you subsequently write other things, so some advantage of having done so; I'll get on to the meat of your answer when I can, but you certainly had about 3 times as much written on assumptions than I would have expected and I fear that you wouldn't have got the "marks per minute" you'd have been hoping for by so doing. ---------------------------------------------------------------------------------------------------------------------------------------------- EF103 is certainly protecting the incident. EF206 reads away from the incident; did you misread the diagram and mean EF207? Option 1. Closure of the branch is sensible; probably better to have made more clear that road transport being provided instead of the rail service. The running of the trains in the Up direction only is a mode only applicable in the immediate aftermath of the incident as a transitional phase, before the main topic of the question comes into play. The freight derailment, even if it is very minor and only involved say the last vehicle when crossing the points from Down Fast to Down Slow isn't going to be resolved in less than half a day; operating the railway in one direction is not an option as all the trains will be at or beyond C with none at the A end of the line. Far more likely would to be terminate trains from A prior to B and then road vehicle substitute to C and run a shuttle for the line beyond there- however if going to do that then need to institute whilst there are still trains at the A end of the line! Certainly something a railway could do and worth a brief mention perhaps, but not really compliant with the question relating to the "operation of trains through station B"! Note also the question asked for a (i.e. one singular) method to be described, yet then goes on to say that it should "a number of possible options"; I don't feel this is as clear as it might be, but interpret it to mean describe one in detail and then, in less detail, sketch out some "variations upon the theme". So looking at your real option: Yes, suspend the branch service as above. Yes you need to be handsignalling via EF427. Not so sure I'd worry about the added complication of going via the GPL; perhaps there is some advantage of allowing a faster train to overtake one doing platform duties but it may be better (safer- one less complication and less disruptive to the opposite direction service for it just to wait its turn. Indeed given that a non stop train more likely to be from EF205 than the stopping service more likely to be from EF101 if there were a need to reorder the trains then could be done by selecting in the appropriate order here. Indeed the trains could potentially be so divided / reordered at station C instead. Of course alternatively we could choose to say that no Down train would be stopped at station B and arrange road transport to / from the next adjacent stations and then dedicate the Up Fast to a clipped wheel path for the Down trains (going via GPL853) and get all the trains from A to present themselves on the Up Slow, hence separating the two directions of flow and once points had been moved into position and clipped/scotched/padlocked as necessary then just left like that. OK delays in each direction as using a one line in each direction, the inconvenience of not stopping at station B (the option of not stopping line EITHER direction may be good as helps line capacity, perhaps less confusing to the passengers and actually keeps them out of harm's way (and minimises the prying eyes) whilst investigation and remedial works are underway. Your answer says Up trains signalled as normal- how can this be when handsignalling is taking place in the area including wrong direction moves on unsignalled routes- where is the opposing route locking etc.? Perhaps in one direction allowing signals to clear and getting some security of the interlocking proving point detection and track section vacancy is an advantage, but it certainly isn't being operated as normal....... I would have thought a single handsignaller would cover both EF101 & EF205; I'd assume both signals held to red with normal aspect sequence on approach so it is just a matter of authorising a train past them and clearly only one of them can be passed at any one time. I think that the pertinent part of the instructions should be outlined rather than hide behind "according to local instructions"; something like: A.
B. if practicable (another suitable person in the signalbox) getting this independently checked prior to C. using a set form of language involving restricted set of defined terms and recognised phonetic language descriptions with signaller taking lead and ensuring that instructions are then repeated back by the driver and confirmed. Looking now at your 3rd option: If you aim to keep traffic moving to/ from the Branch you need to recognise that there is not only a Safety implication but also a throughput disbenefit as well to counterbalance the advantage of being able to move some particularly vital traffic in that direction (ok can use road transport for people; can't really do that for freight other than for its entire journey). What you don't seem to have recognised is that another portion of the layout now effectively becomes a single line with the need procedurally to control the opposing direction movements. It is not so much the traffic from EF719 that you should have concentrated on (no real difference to EF101 etc) but that ONTO the branch from EF206. Whereas I'd assume that this signal and route would be operative, you can't work this normally with the potential for handsignalled moves opposing it. Think also about the branch itself; seems that you need to institute some form of pilotman working. I do not know the Northern Ireland Railway Rulebook, so it may well be that description of the last section is perfectly correct- it is not exactly what I'd have expected in all respects but as an examiner I'd probably accept it without checking up on the detail as there is nothing there that "rings false". It is certainly having some coverage of such, although I think I'd have integrated it in the main description and feel that the question was primarily after the considerations at a higher level of what "routes" would be available, which points would be operated via the IPS, which would be moved to a lie and then secured in that position, whether a form of ticket working or pilotman working would be deployed etc. rather than too much of the lower level detail. My overall feeling was that there was a lot of writing and it is clearly a question where you have some elements of relevant knowledge but less convinced that you showed an understanding at a higher level of what can reasonably be achieved by handsignalling in a practical sense still to achieve any form of useable service, rather than just move one train around the layout. I think that the time that it would have cost you to have produced your answer would not have gained the level of marks which fully justified. I guess you would just about have got a pass mark. If you really did in 32 minutes (have some doubts as rather more than most can do, but writing perhaps does demonstrate that you were "going some") I suppose that is heading for a borderline pass overall in the paper. However I think it best to work on the basis of only 25 mins actual writing on a question, as essential admin and some initial thinking time etc. do need to be factored in somewhere. On that basis, even 32mins is beginning to look to be a 20% overrun and therefore at the expense of marks that you might otherwise got more easily from another question on the paper (whose time allocation I consider you'd have sacrificed to produce this answer).
PJW
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