Loops

[RichmondCommu]

Hi everyone, hopefully someone can answer the following question.

Basically when a train is diverted into a loop to let another train overtake how much notice is the driver given? Is he or she told that they are due to be held in a particular loop before they take control of a train or is it a decision made by signalling staff once the train is under way? If it’s the latter, in terms of signals how much notice is given to the driver that he needs to slow down in order to enter the loop from a maximum speed which I imagine would be 75 mph?

I look forward to your replies!

 

[driver9000]

If the train is booked to be looped it will be in the Working timetable and on the drivers diagram that his/her train will be looped at that location.

If the train needs to be looped to allow a late running express pass it, then the driver will be given notice using the signalling by being checked down by yellows and then given the appropriate junction indicator at the loop entrance. A passenger driver needs to be more aware of being looped because a passenger train is not normally permitted into a Goods loop. In order for a passenger train to use a Goods loop/line it needs to be authorised by the signalling supervisor and in my experience the train is stopped at the signal controlling the entrance to the loop and the I've been told I'm to take my train into the loop. The driver will know which loops are passenger loops and goods loops through his route knowledge.

In your example of being looped from 75mph, the loops that are on my routes I would be checked by a single yellow because the signal controlling the entrance to the loop would be at danger as it is controlled approach for the 15mph points.

 

[RichmondCommu]

Driver9000, many thanks for that. How are freight and passenger loops differentiated? I'd assumed that all loops were open to passenger and freight trains?

 

[driver9000]

Goods loops and lines aren't fitted with AWS.

They can be differentiated by name of line ie Down Goods or by location ie Anytown Goods loop or Anytown Passenger loop. The driver will know which loops are which through their route knowledge even if it's not obvious by the name of the loop. A driver of a freight train must also consider the length of the train against the length of the loop as the train could be too long for the loop. The lengths of loops is included in the Sectional Appendix measured in SLUs (standard length units). I think 3 SLUs equals 21 metres.

 

[strange6]

Quite a popular little loop lies just outside Manchester Victoria just before the vitroil works box section on the way to Rochdale. My train is sometimes stopped by a red whilst a late running Leeds service goes around us. The driver always gets out of the cab and goes to speak to the signaller so I would assume by him doing this, this is quite often an instant decision by the signaller on this particular stretch.

 

[GB]

Driver9000, many thanks for that. How are freight and passenger loops differentiated? I'd assumed that all loops were open to passenger and freight trains?

As Driver9000 says, goods loops are not generally fitted wth AWS but they also do not always have overlaps beyound the exit signal and the exit signal itself maybe a ground position light signal for which passenger trains in service are not permitted to start from.

 

[strange6]

As Driver9000 says, goods loops are not generally fitted wth AWS but they also do not always have overlaps beyound the exit signal and the exit signal itself maybe a ground position light signal for which passenger trains in service are not permitted to start from.

No AWS on goods loops? Gosh, I bet you guys really do have to concentrate hard, especially with all that weight you pull as well sometimes!

 

[route:oxford]

On a single track route...

What differentiates a loop and a stretch of double track.

Eg, once the current works are complete, will the Oxford-Cotswolds route be single track with loops, double track with single section or something else?

 

[Railsigns]

Many passenger loops don't have AWS.

 

[Rugd1022]

Some Goods Loops do have AWS... the down Loop at Bordersley certainly does (spent hours in there ).

 

[The Planner]

The lengths of loops is included in the Sectional Appendix measured in SLUs (standard length units). I think 3 SLUs equals 21 metres.

21 feet to a SLU.

 

[rail-britain]

Many passenger loops don't have AWS.

It would be more dependent on the signalling rules that apply in that area, but in the majority of cases the loop will have AWS and TPWS

Equally, there is not really any such thing as a "passenger loop", it would be more a "main loop" and "goods loop"

As above, the driver will be aware of the route layout and seeing danger signals may anticipate being sent to the loop
Equally, the driver can usually work out where standing time may be required by the calling points, example
Carstairs arr 13:12
Carstairs dep 13:31
Abington arr 14:03
Abington dep 14:11

 

[Tomnick]

There is such a thing as a passenger loop; indeed, many lines are designated as such ("Up Passenger Loop"). Whether booked to stand in a loop or not, the route indication on the last signal in rear of the loop (with, in virtually all cases, approach control on that signal) is the only definite information given to the Driver that he's being put inside.

 

[Zoe]

Also regulation TS1/4.13.1.1 requires that for a signal that does not have approach release you must not clear the signal until the trainis close to the signal and the speed has been reduced. This regulation only applies for a train not booked to take the dirverging route though. If you are booked to take the route then you'd be expected to know to slow down.

 

[Tomnick]

In that case though - almost certainly only going to occur in a mechanically signalled area - the distant would be 'on', so the Driver would be braking for the signal protecting the junction until it comes into sight.

 

[driver9000]

21 feet to a SLU.

I knew there was a 21 in it.....

 

[GB]

I knew there was a 21 in it.....

To be fair you are also correct.

When refering to vehicle lengths they are either refered to as....

Axle vehicle = 1 Slu = 7m

or

Bogie vehicle = 3 Slu = 21m

These are generic values though and technically not accurate.

 

[matchmaker]

Driver9000, many thanks for that. How are freight and passenger loops differentiated? I'd assumed that all loops were open to passenger and freight trains?

The main difference between passenger and goods loops in the past was that any facing points on passenger loops had to be fitted with facing point locks. This did not apply to goods loops.

 

[Wyvern]

What about diverting through a carriage wash as happened recently.

How would that be arranged and authorised?

 

[First class]

What about diverting through a carriage wash as happened recently.

How would that be arranged and authorised?

For TOC/FOC staff, usually done through the Person in Charge of Sidings (PICOS) also known usually as the Shunter, is unsurprisingly "in charge" of what enters the yard. Network Rail is asked to set the points into the siding, and the PICOS signals the train through the depot accordingly, and can use hand signals, whistles, radios and lamps.

The shunter then contacts NWR and asks him to set the points from the depot back on to the NWR infrastructure.

 

[ralphchadkirk]

For TOC/FOC staff, usually done through the Person in Charge of Sidings (PICOS) also known usually as the Shunter, is unsurprisingly "in charge" of what enters the yard. Network Rail is asked to set the points into the siding, and the PICOS signals the train through the depot accordingly, and can use hand signals, whistles, radios and lamps.

The shunter then contacts NWR and asks him to set the points from the depot back on to the NWR infrastructure.

All points (certainly facing, not so sure about trailing) in the yard that the train would travel over would have to be clipped and plugged. Thus, an NR MOM would be present.

 

[Wyvern]

I should have mentioned it was a service train with passengers on board.

 

[GB]

Points that are not on Network Rail infrastructure can be clipped up by any qualified staff.

 

[ralphchadkirk]

Points that are not on Network Rail infrastructure can be clipped up by any qualified staff.

I'm sure I read somewhere that a MOM was present for it?
Thanks for letting me know though - I didn't realise if it wasn't on NR infrastructure then it could be clipped by any qualified person.

 

[chuffchuff]

What about diverting through a carriage wash as happened recently.

How would that be arranged and authorised?

NR and Yard Sup and the route is signalled anyway

 

[MacCookie]

It would be more dependent on the signalling rules that apply in that area, but in the majority of cases the loop will have AWS and TPWS

Equally, there is not really any such thing as a "passenger loop", it would be more a "main loop" and "goods loop"

As above, the driver will be aware of the route layout and seeing danger signals may anticipate being sent to the loop
Equally, the driver can usually work out where standing time may be required by the calling points, example
Carstairs arr 13:12
Carstairs dep 13:31
Abington arr 14:03
Abington dep 14:11

Funny how there's "not really any such thing as a "passenger loop"", yet that's exactly what Carstairs and Abington are - Up and Down Passenger Loops. Unless UPL and DPL mean something else?

Ewan

 

[matchmaker]

Funny how there's "not really any such thing as a "passenger loop"", yet that's exactly what Carstairs and Abington are - Up and Down Passenger Loops. Unless UPL and DPL mean something else?

Ewan

In my copies of the Sectional Appendix:

UPL = Up Passenger Loop
DPL = Down Passenger Loop
UGL = Up Goods Loop
DGL = Down Goods Loop
CL = Crossing Loop

Unless modern naming is different.