Cornwall resignalling query

[Annetts key]

I can’t find a good video on YouTube for a modern AOCL installation that uses LED wig wag road traffic lights. But here’s a video showing the older type installations:

Video shows an AOCL level crossing, with close ups of the tungsten lamp wig wag road traffic lights and the operation of the crossing as a train passes over it.

 

[The Planner]

Many thanks for this.

Through a forum I have been linked into an article on the railengineer.co.uk site. The article, dated April 2022, gives some information on the plans for the Newquay, Looe and Gunnislake lines.

Gunnislake line:
- the crossings at Okel Tor and Sandways will be changed from open crossings to AOCL (Automatic Open Crossing Controlled Locally): the road layouts at those locations (the crossings are next to road junctions) mean that barriers cannot be installed.

Newquay line:
- New passing loop for Goss Moor to facilitate an hourly service
- Reinstatement of the second platform at Newquay which will enable more through trains from beyond Par.

Looe line:
- conversion of the crossings at Lodge Farm and Terras from open crossings to ABCL.

The aricle, for anyone interested, can be found at https://www.railengineer.co.uk/a-modular-approach-to-signalling-in-cornwall/ and gives a good amount of detail. No mention is made of what will happen to St. Blazey SB though which I guess will abolish with control passing, as with Lostwithiel, Par and Truro, to Exeter?

Dave

Scanning through some of the plans, all the sidings around Lostwithiel apart from the loops go. New crossover from the Down to Up Main prior to Truro for turnbacks in P3 by the looks of it. Not got the Penzance and Newquay plans.

 

[MarkyT]

Note locally monitored crossings like AOCL, ABCL are sometimes triggered by traincrew operating a pushbutton. This is usually implemented where a crossing is next to a station that all trains call at for the direction starting away from the platform before passing over the crossing. The opposite direction would usually be triggered automatically by track circuits and treadles in the normal way. Most AOCLs were converted to or replaced by ABCLs in recent decades.

 

[Railsigns]

Most AOCLs were converted to or replaced by ABCLs in recent decades.

The majority were converted to AOCL+Bs by the addition of half barriers. Those that were due for renewal were converted to ABCLs.

 

[Ashley Hill]

The road approaches to Okletor crossing are particularly nasty. One way us a steep downhill approach with little sighting for the road user,the other way is off an immediate 90 degree turn straight onto the crossing. When the unit driver stops and sounds the horn before proceeding the road user often misbelieves this to be the unit driver giving right of way to them.

 

[MarkyT]

The majority were converted to AOCL+Bs by the addition of half barriers. Those that were due for renewal were converted to ABCLs.

The AOCL+Bs were the clever engineering solution to quickly convert large numbers of existing and often fairly new AOCL installations without full renewal being required. There may be some very minor differences in the operating sequence and sometimes the detailed layout of equipment compared to an all-new ABCLs.

 

[Railsigns]

The AOCL+Bs were the clever engineering solution to quickly convert large numbers of existing and often fairly new AOCL installations without full renewal being required. There may be some very minor differences in the operating sequence and sometimes the detailed layout of equipment compared to an all-new ABCLs.

There are some differences in how they operate under local control, and different failure modes.

 

[DaveHarries]

I assume Okeltor & Sandways are the two crossings where the train currently comes to a grinding halt before restarting over the road?

For anyone not familiar with the Okeltor crossing it has many difficulties as will be seen from the attachments included with this post: the views are taken from Google Earth. The views from either side are not very favourable to road or rail traffic.

The first two photos - okeltor1.jpg and okeltor2.jpg - are from the Bere Alston side of the crossing: okeltor1 shows the view towards Gunnislake while okeltor2 shows the view towards Plymouth. The road incline between road and rail in the first view, which is more clearly visible in the second view, might make the view for any car intending to turn left to cross the line rather tricky.

okeltor3.jpg and okeltor4.jpg are from the Albaston side of the line: okeltor3 is towards Gunnislake - note the curve to the left which makes it tricky for road and rail transport to see each other - and okeltor4 is the view towards Plymouth on the same side of the line. okeltor5 is the view from the Bere Alston side to the Albaston side and shows the problems with visibility for approaching traffic due to the embankment and vegitation on the left which can also be seen behind the sign in view 4. Trains to Plymouth would pass right to left in view 5. The planned upgrades to this crossing will be a big improvement but perhaps long overdue: I can't help wondering why they weren't done sooner.

Dave