Typical UK signalling distances

[Carlcee]

Hi guys,

I'm creating a route based loosely around the West Midlands area (I say 'loosely' because it will be a fictional route, but feature rolling stock that were based around the West Midlands region in the mid-90s).

I just wondered if there is a typical distance between signals in the UK on long high-speed sections of track (for example, the West Coast Main Line between Birmingham New Street and Coventry).

Just wondered what an average distance between each signal would have been on a line such as the West Coast line in the mid-90s (before they were spaced further apart upon the introduction of the Pendolinos).

Any help would be appreciated

Thanks guys.

 

[rjhowie]

I don't have the aswer but would be interested to see a reaction to this as I feel this question did come up before a time back? I am building the whole of Ulster's NIR and I am going to place signals roughly three-quarters of a mile apart although with so much being rural a mile is tempting?

 

[nexusdj]

Distance all depends on what they can fit comfortably between controlled junctions / level crossings etc .
Most of it comes down to the route knowledge of the driver where they are taught which signals are closer than others and to take that into account when braking the train .

You'll find as the signalling is modernised on routes that the distance between signals has actually been reduced. The feeling being that modern trains have a far better braking capability than what an unfitted or partially fitted freight had back in the 60's and 70's . The speed range of trains that modern signalling has to cope with has decreased with most now in the 50 to 125mph area whereas the older systems had to contend with freight running as low as 25mph.

More use of 4 aspect signalling as well assists the modern driver as you can judge the speed of the train that your following better as you always know that there 2 signalling sections between you and the red signal . This allows you to experiment with your train speed until you see either a green or a succession of double yellows

When they planned the recent resignalling of the line between Leamington and Banbury north the original plan was to put in 3 aspect signals until it was pointed out by the freight companies that their drivers are taught to go past a single yellow at no more than 40 mph with the brake in ready to stop at the red . This isn't any good for maintaining paths especially if it's a heavy freight train as it will take longer to regain it's original speed , plus any train following the freight will catch it up and the delay will start to snowball back down the line. Better to keep things moving than stop start , stop start

 

[Carlcee]

Thanks Dave. I had looked on Google in the past for the answer - but couldn't find one, so that explains why. It makes perfect sense really.

 

[Carlcee]

Better to keep things moving than stop start , stop start

I wish they'd take note of this in Coventry when the Council decide to stick bus lanes and traffic lights everywhere on our roads. :hehe:

 

[Vern]

It all depends on line speed, traction braking capability and service density. As a rule of thumb on the average double track route with 90 MPH to 100 MPH line speed and four aspect signalling, you would be looking at signals 1000 - 1500 yards apart, ergo when a driver first sights a double yellow he has around 2000 yards to brake to a stand at the red.

There are variations to this of course and you often find on lightly trafficked lines where colour light signalling has replaced manual semaphores, these are spaced more widely in which case you will normally get the main aspect preceded by a repeater (effectively colour light distant) at the braking distance. Typically signals may be 6 or 7 miles apart in these situations, such as the Devon Banks between Hemerdon and Totnes or the Avon Valley from Bathampton to Bradford Jn.

 

[colourlight]

As a professional signaller I can tell you there is no standard distance between main aspect signals. Various factors have to be taken into consideration such as linespeed, type of signalling, braking distance and sighting distance and also spacing at specific locations. Where the full braking distance cannot be achieved at those locations train speed is contolled by signalling restrictions such as, if a signal cannot be cleared the signal next in rear will not clear until the berth track circuit of that signal has been occupied for 30 seconds. 3 aspect signals are placed at full braking distance and 4 aspect signals at half the braking distance and semaphore signals are placed in specific places at the location they contol and train speed at those locations is contolled to a certain extent by the signaller to prevent SPAD,s. In Trainz, signals are generally placed a mile apart but you always have to take into consideration the linespeed.

 

[Telemendas]

At least for the UK, you can find useful distance tables in the Railway Group Standards website (http://www.rgsonline.co.uk/). The tables are in document GKRT0075 - Lineside Signal Spacing and Speed Signage.