North American Junctions and other things....

[trisonic]

Thanks, guys. That is exactly what we wanted to find out................I chose the UK as an example because this is primarily a British site.

 

Best, Pete.

 

 

Best, Pete.

[dave1905]

You do realize of course that when the train is authorized to reverse directions and shove back into the siding, it is making a facing point move? 8-)

 

In true "double track" railroad the majority of crossovers are trailing point (rule 251 current of traffic operation), but in CTC the whole concept is to increase the flexibility so the ability and benefit to cross a train over far outweighs the risk of derailing on a switch. If you maintain the switches, a facing point switch isn't a problem. A derailment due to a facing point switch on a main track is pretty rare. More trains derail due to broken rails or component failures on the cars themselves.

[BR60103]

2 comments on things a couple of pages back.

If you trace the rails on Adrian's map to the northwest you will come to the the junction I talked about, except that it's now under major renovation.

Bayview Junction is actually a wye and involves 2 railways (plus tenants). Search Google maps for Burlington, Ont -- Valley Inn Road. A great project for the flower modeller as it's located in the Royal Botanical Gardens.

[Glorious NSE]

You do realize of course that when the train is authorized to reverse directions and shove back into the siding, it is making a facing point move?

 

Technically yes, but the move against the current of travel is a low speed shunt move, the objective is to not have facing points on the 'running' route.

 

In true "double track" railroad the majority of crossovers are trailing point (rule 251 current of traffic operation), but in CTC the whole concept is to increase the flexibility so the ability and benefit to cross a train over far outweighs the risk of derailing on a switch. If you maintain the switches, a facing point switch isn't a problem. A derailment due to a facing point switch on a main track is pretty rare. More trains derail due to broken rails or component failures on the cars themselves.

 

Yes - but that ignores that it's a regulatory thing and not at all maintainence thing - at some point in the past (and you're probably talking back in the 18xxs here) there will probably have been an accident caused by a facing switch moving under a train, the papers will have been complaining about how that is unacceptable, people will be writing to their MPs complaining about how railways are unsafe and the government will have responded by slapping down a rule preventing companies using such an unsafe practice. (*)

 

If you want an up to date corrolary for your side of the water then try the recent requirement for all lines carrying passengers or Hazmat to have PTC fitted by 2015 (despite there not really being a way of doing that at the time the ruling was made) when the government decided that commuter train engineers can no longer be trusted to just read signals. (**)

 

(Not just a US thing either, Europe is suggesting we also install magic signalling systems that don't yet really exist...they just make the rules, they don't have to make them work...)

 

Over here cue the companies head offices sending out decrees that these expensive changes must be avoided where possible and all of a sudden all over the country we have trains going backwards into sidings, whereas your side of the water they are suddenly trying to reroute Hazmat stuff to try and minimise the amount of line that needs to have the technology and rushing round like headless chickens trying to make the technology work effectively.

 

Neither is neccesarily the most sensible and cost effective way forward, but it's what companies do when they get rules slapped on them from on high.

 

As for the CTC angle - that is why it's no longer an issue on more modern layouts.

 

Once you get to powered switches that self-lock instead of manual switches moved from an interlocking frame then there is no extra cost for including a facing point lock and the restriction goes away entirely...

 

And even before that you have a gradual eroding of it as 'the way it must be done' as (I suspect almost from the moment the change was made!) the operating departments responsible for busier bits of railway would be busy pointing out that the cost of using an occasional facing point lock to let trains run into passing loops forwards instead of having to stop and back in wasn't actually a large sum compared to the cost of the capacity it would free up...

 

(* And to be fair - much as we've already had mention of the famous 'robber barons' on your side of the water if you dig back through UK railway history there was good reason for the government to be getting involved as plenty of British companies didn't put safety on the top of their to-do lists, there was great reluctance to invest in any form of continuous braking from some of them for instance, even for passenger trains. That was finally sorted after a horrible accident where a packed passenger train stalled on a grade, was split to double the hill and rather predictably the unbraked portion ran away into the path of a following train, but even after continuous brakes came in they resisted 'fail safe' continuous brakes...and so on...and so on...both sides of the water there seems to be a saying that the rulebook is written in blood, and there is much truth in that.)

 

(** And eventually I can see big advantages in all US routes having PTC once there's a system that works, but the scope of the original ruling is huge when slapped onto an unsuspecting industry, and the vast majority of the industry bears little resemblance to the company behind the original accident that sparked it!!)

 

 

[Scottish Modeller]

At least it ended well - unlike Australia where the story goes something along the lines of, "there was an Englishman, and Irishman and a Scotsman".

Then the Welshman came in and said....

 

It's got to be narrower than that!

 

Thanks