Facing and Trailing Points

[John_Hughes]

One odd thing about FPLs is that some lines which seem to have survived BoT inspection in the 20th Century never actually had them installed.

 

The Ffestiniog was certainly using weighted levers and nothing else on the loop at Tan-y-Bwlch in the 1960s, and when the Welsh Highland opened in the 1920s several of the loops also apparently had nothing more than similar weighted levers. I am aware that the signalling requirements for light railways were much laxer than for other lines, but I didn't think this applied to the provision of FPLs.

 

And what was/is the position on street tramways? I'm pretty sure that they didn't have them on the old LCC/London Transport systems that I remember from my childhood.

 

Can anyone enlighten me please?

[coachmann]

Would it matter on a street tramway if a tram left the rails at facing points and rambled over the cobbles? I heard tales when on't buses about such things in tram days and passers by used to just help push the thing back on the rails. Today it would be an H&S issue!

[The Stationmaster]

One odd thing about FPLs is that some lines which seem to have survived BoT inspection in the 20th Century never actually had them installed.

 

The Ffestiniog was certainly using weighted levers and nothing else on the loop at Tan-y-Bwlch in the 1960s, and when the Welsh Highland opened in the 1920s several of the loops also apparently had nothing more than similar weighted levers. I am aware that the signalling requirements for light railways were much laxer than for other lines, but I didn't think this applied to the provision of FPLs.

 

And what was/is the position on street tramways? I'm pretty sure that they didn't have them on the old LCC/London Transport systems that I remember from my childhood.

 

Can anyone enlighten me please?

 

Light Railways (standard gauge) were/are required to have FPLS (if they run passenger trains) but they have long been exempted from having locking bars 'provided the lever working the points is alongside them', also economical FPLs were 'recommended' for light railways. That of course leaves open the question about how some of them managed to getaway without complying although I suspect their story was that the points were secured by padlock - certainly FPLs do not always seem to figure in photos.

 

The past situation for n.g lines is far less clear but they obviously got away without FPLs for many years. More recently the Inspectorate seem to insist that anything of wider gauge than c.15inches should have FPLs although 'outside' FPLs are acceptable on n.g. lines where there is insufficient room between the running rails. Currently the Inspectorate are not very keen on weighted points even on 15 inch(ish) gauge lines and like to see at least some form of detection and indication installed instead of just relying on the lever weight (and luck).

 

The Welsh Highland and Ffestiniog do, of course, use a modernised version of the weighted point with their own design employing quite sophisticated hydraulics and damping mechanisms, and they have been cleared for use by the Inspectorate.

 

The BR self-acting hydraulic mechanism (for standard gauge lines of course) was also mentioned earlier in this thread but that equipment is currently being removed from some lines due to difficulties in maintaining it owing to problems obtaining spare parts.

[John_Hughes]

Thanks - that matches what I'd observed.

 

What prompted the query was a fascinating article in the latest issue of The Colonel about the (short-lived) use of petrol buses on the (standard gauge) Derwent Valley Light Railway. The DVLR bought a matched pair of these in May 1924, spending just over £1,000 for them and even installing small turntables at York and Skipwith so that they could be turned and thus run singly rather than always back-to-back.

 

As this would mean the line was no longer operated on a One Engine In Steam basis the Ministry insisted on inspecting the new arrangements, which involved four staff-and-ticket sections with a 'loop siding' installed at each. The Company begged to be allowed not to have to install signals In view of the poor financial position of this Co.

 

The new arrangements were duly inspected and approved - without signals! - and the service was duly started, though it lasted only a short while.

 

I very much doubt if the 'loop sidings' had FPLs fitted, especially in view of the financial difficulties the company was suffering, but they do seem to have got away with it!

[PLD]

And what was/is the position on street tramways? I'm pretty sure that they didn't have them on the old LCC/London Transport systems that I remember from my childhood.

 

Can anyone enlighten me please?

 

Most were traversed at relatively low speeds (typically 4, 6, or 10 mph limits in force) so potential impact of any derailment is much lower.

 

Any sort of 'bolt' type locking mechanisim as used on the main line railways would be very rare, Most traditional tramways relied on either a weighted lever (for exposed sleeper track) or an underground counter-balance to hold the switch rails against the stock rail. Sometimes where trafic flow was normally biassed to one diverging route such as passing loops on a single line section this may be suplemented with springing meaning the point had to be physically held or chocked in the reverse position.

 

For a photo and diagram of a typical counter-balance mechanism, take a look at this RAIB report into what happens when it goes wrong...

 

Paul

[John_Hughes]

The RAIB report doesn't come up, as it happens; does it refer to the Great Orme Loop Incident of a couple of years ago?

 

I remember the Pointsmen - most of whom didn't have little huts to shelter in! - in London, and the illuminated signals showing which way the points were set, usually mounted on a convenient overhead support; they always fascinated me as a child. And, of course, the odd occasions when the driver had to lever the blades over with his pinch-bar, which was always kept in the cab.

 

Sigh......!

 

(When the TRPS started to get serious in the late 1950s, Towyn Pendre got itself a proper ground-frame at the Wharf end. Ah, the times I've worked that in days gone by...)

[PLD]

The RAIB report doesn't come up, as it happens; does it refer to the Great Orme Loop Incident of a couple of years ago?

 

Sorry link corrected....

 

It's actually the derailment at Blackpool Pleasure Beach in 2006.

 

The GOT is altogether different in the way it operated with one car always using one side of the loop and the other car the other side regardless of which is heading in which direction. I know the points are set by the passage of the cars but I don't know what their locking arrangements are...

[martin_wynne]

However back in the snows of 1978 one of my Shunters ran an HST through the trailing end of a flat-bottom crossover which was part way over but snow/ice bound without doing any discernible damage at all whereas I have seen bullhead switch rails crippled in similar situations.

Hi Mike,

 

RAIB report published today is relevant: http://www.raib.gov.uk/cms_resources/100318_R042010_Greenhill_Upper_Jcn.pdf

 

regards,

 

Martin.

[StaffsOatcake]

One odd thing about FPLs is that some lines which seem to have survived BoT inspection in the 20th Century never actually had them installed.

 

The Ffestiniog was certainly using weighted levers and nothing else on the loop at Tan-y-Bwlch in the 1960s, and when the Welsh Highland opened in the 1920s several of the loops also apparently had nothing more than similar weighted levers. I am aware that the signalling requirements for light railways were much laxer than for other lines, but I didn't think this applied to the provision of FPLs.

 

 

Can anyone enlighten me please?

 

Tan-y-Bwlch and Minfford are now operated by Siemens SGE 30v motor points that are activated via either the push button ground-frame or a the relay interlocking that is activated by the token machines. Bleanau Ffestioniog is operated by a LNWR pattern lever frame working Siemens SGE 30V motor points. All these have an FPL system as does the ground-frames at Portmadoc, Boston Lodge and Glan-y-Pwll. Requirements of HMRI for FPL to be fitted.

 

However,

 

Tan-y-grisau uses a strange contraption that is similar in many ways to the weighted/hydraulic points of years gone by but modified to meet the latest standards. These are also in use on the 'Dark Side' (Welsh Highland Line, which I don't personally get involved with yet) as well as something resembling an Hydragas systemem .

 

All current Heritage Railways are classified as Light Railways, as that is what they get the license to operate. FPL's have to be used if any passengers are carried. Otherwise the points must be clipped,padlocked and deemed secure for a passenger train to pass over them in the facing direction

[John_Hughes]

Thanks, Oatcake, I was aware of the current situation in general terms, but that is helpful. Of course, the Isle of Man has its own rules on this topic, as the speed of some of their trains demonstrates!

 

What about that interesting incident at Blaenau a few years back when an Up train did something interesting across the station throat? Was that an FPL failure, as I heard, or was there more to it?

 

Don't worry, I shan't tell anyone...

[Grovenor]

Many thanks for the pic.

 

Here's a drawing of an older BH design:

 

Martin.

That is not an older design in the sense that it replaced the other, just a different design, probably actually newer although I don't know the dates. Similar 'butterfly cranks' are used as part of Electro pneumatic machines.

[csvt2004]

Just going back to the Settle-Carlisle. There used to be a Hellifield to Hawes train. So how did that get across to the branch at Garsdale?

[hexagon789]

Just going back to the Settle-Carlisle. There used to be a Hellifield to Hawes train. So how did that get across to the branch at Garsdale?

I believe it drew forward, reversed over the crossover and then set off on its merry way.

[csvt2004]

I believe it drew forward, reversed over the crossover and then set off on its merry way.

 

So, a passenger train travelling over a set of trailing points in the facing direction. An exception to the rules?

Also happened on a daily basis at Halwill Junction. Number 16 points if I remember correctly. 

[jim.snowdon]

So, a passenger train travelling over a set of trailing points in the facing direction. An exception to the rules?

Also happened on a daily basis at Halwill Junction. Number 16 points if I remember correctly. 

They may have been provided with facing point locks, in which case the rules were being complied with. The requirement is that passenger trains (more correctly, trains containing passengers - empty stock doesn't count) can proceed through points in a facing direction only if they are locked, or otherwise confirmed as closed and secured against movement by a suitable means, usually a clamp that has been locked.

 

Jim

[phil-b259]

They may have been provided with facing point locks, in which case the rules were being complied with. The requirement is that passenger trains (more correctly, trains containing passengers - empty stock doesn't count) can proceed through points in a facing direction only if they are locked, or otherwise confirmed as closed and secured against movement by a suitable means, usually a clamp that has been locked.

 

Jim

 

Or the Midland Rly told the HMRI they would make everyone get off the train while it swapped lines empty, rejoining it at another platform. What happened when the HMRI wern't around though.....

[The Stationmaster]

They may have been provided with facing point locks, in which case the rules were being complied with. The requirement is that passenger trains (more correctly, trains containing passengers - empty stock doesn't count) can proceed through points in a facing direction only if they are locked, or otherwise confirmed as closed and secured against movement by a suitable means, usually a clamp that has been locked.

 

Jim

 

Not necessarily.  A train conveying passengers could be shunted in the facing direction through a normally trailing point provided that the point was detected by a ground signal.  However if there was to be a regular movement of a train conveying passengers through such a point then an FPL (and lock bar or track circuit) was required; of course it also depended on how one defined 'regular'.   In the real world, especially with long trains, we always clipped up anyway as it didn't take long and it provided that extra little bit of security 'just in case' but there was nothing in the Rules & Regs to prevent us making such a move through normally trailing points without first clipping them, provided they were detected by a signal cleared for the movement.

[bécasse]

One historical oddity is that the erstwhile Great Northern Railway not only habitually installed FPLs on goods lines, it sometimes installed point locks on trailing points too, usually in locations where goods trains were regularly set back through them.

 

I believe that the reasoning has been lost in the mists of time but was probably another one of this evaluations that considered the cost of fitting locks (without detection bars) was cheaper over time than the cost of clearing up after derailments.

[meil]

Or the Midland Rly told the HMRI they would make everyone get off the train while it swapped lines empty, rejoining it at another platform. What happened when the HMRI wern't around though.....

The Midland habitually used economic facing point locks so you wouldn't have a separate FPL lever.

[The Stationmaster]

One historical oddity is that the erstwhile Great Northern Railway not only habitually installed FPLs on goods lines, it sometimes installed point locks on trailing points too, usually in locations where goods trains were regularly set back through them.

 

I believe that the reasoning has been lost in the mists of time but was probably another one of this evaluations that considered the cost of fitting locks (without detection bars) was cheaper over time than the cost of clearing up after derailments.

 

It was standard practice on the WR in the 1970s (and probably earlier on some lines) to install FPLs on signalbox or ground frame worked facing points in any new work on goods only lines - because it minimised the risk of derailments.