Driving Trains in foggy weather

[JD2168]

As seen of the last few days it has been very foggy. How do Train drivers find these conditions with seeing the signals & other signs along the journey. Always looks very challenging in this sort of weather.

 

[800301]

As seen of the last few days it has been very foggy. How do Train drivers find these conditions with seeing the signals & other signs along the journey. Always looks very challenging in this sort of weather.

Generally we drive the same way, usually you can pick out some sort of landmark or have counted how many AWS’s you’ve been over to get some idea of where you are, if ever unsure the brake is normally your best option, some find it easier than others. Generally there aren’t any signs that we need to see as our route knowledge should be able to tell us what to expect, the newer style LED signals are very bright and while it might take a while for them to appear out of the abyss again you should know what to expect based on previous signals and location, what throws a spanner in the works is getting restrictive signals in places you don’t normally get them and knowing exactly where you red signal is

 

[Sly Old Fox]

If you can’t keep to time in the fog you shouldn’t be driving (signals and other variables permitting).

 

[AverageJoe]

If you can’t keep to time in the fog you shouldn’t be driving (signals and other variables permitting).

although I myself drive at line speed in this weather due to my route knowledge I think to make the above statement is wrong.

TW1 issue 19
22 - if you cannot see signals, block markers or line side indicators soon enough to react to them during poor visibility, you must reduce the speed of your train as you consider necessary.

Therefore if a driver does choose to reduce speed and therefore doesn’t keep to time he is doing nothing wrong and is displaying responsible defensive driving.

 

[MP33]

My father claimed that, after the Lewisham accident. There only had to be smoke from a bonfire in a line side garden, to reduce the speed limit to a crawl.

 

[dk1]

Makes no difference to me if driving in thick fog. Will still keep time. The only route that can take a hit on our patch is the East Suffolk line as the locally monitored AOCL+B and ABCL level crossings require sighting of the white flashing light and it’s the train drivers responsibility to ensure the crossing is clear.

 

[Dstock7080]

Could be challenging at full speed on LU with green to red signals and only a fog repeater placed 400’ (121m) in advance of the red, less than a trains length!

 

[norbitonflyer]

AWS, and more recently TPWS, control systems such as ATP and ETCS give the driver an indication of the signal condition without being able to see it at all. Except in very extreme circumstances no signal should be more than one degree more restrictive then the previous one (so a green should only be followed by another green or a double yellow, for example). On the Underground there are tripcocks which should stop a train before reaching whatever obstruction a red signal is guarding.

EDITED

 

[martin2345uk]

Driving on cab signalling in the thick fog is fun, you don’t really need to be looking for anything lineside, but yesterday it got a bit challenging when the signalling got restrictive and suddenly you’re looking for non-illuminated lineside boards and drop/raise pantograph signs

 

[RGM654]

I remember a German Railways advertisement many years ago saying something like "What do you mean fog? There are still trains."

 

[choochoochoo]

The only time I drive any slower than normal in thick fog is after passing a single yellow signal.

Route knowledge means I know where that next signal is, but not being able to see as far ahead as usual means I can’t as accurately judge my distance from it. So I slow down and aim to drive at a speed that means when I pass the associated AWS for it I can hit the brake and stop.

 

[Deepgreen]

What people often regard as 'fog' these days is really not a patch on the fogs/smogs experienced in the days of the Lewisham disaster, for example. Modern signalling copes with modern fog perfectly well (and far better than previously). As an aside, I wish car drivers would stop their panic reactions to a slight mist/rain by putting their fog lights on at the drop of a hat - yet more road light pollution and dazzle is usually less safe, rather than more.

 

[ainsworth74]

Is there any difference in Absolute Block signalling areas with semaphores for drivers or do they proceed as with other areas? I am of the impression that signallers of such places are required to report if specific siting points are not visible due to fog? So does this have implications for drivers?

 

[PudseyBearHST]

100mph max for me

 

[Ashley Hill]

Is there any difference in Absolute Block signalling areas with semaphores for drivers or do they proceed as with other areas? I am of the impression that signallers of such places are required to report if specific siting points are not visible due to fog? So does this have implications for drivers?

Fog marking points,generally about 200 yds from the box. It was either a signal,structure or marker that when it could not be seen during fog then it was officially foggy and Fogmen were called out to repeat the distant signals to the drivers. If the distant was “on” a detonator was placed on the rail and the driver shown a yellow handsignal. If “off” the the detonator was removed and the driver shown a green handsignal.
I’m not aware of anywhere in this country where “shooting the distants “ is still carried out. It’s certainly not in the rule book anymore.

 

[12LDA28C]

AWS, and more recently TPWS, give the driver an indication of the signal condition without being able to see it at all. Except in very extreme circumstances no signal should be more than one degree more restrictive then the previous one (so a green should only be followed by another green or a double yellow, for example). On the Underground there are tripcocks which should stop a train before reaching whatever obstruction a red signal is guarding.

How does TPWS give a driver an indication of the aspect of the signal they are approaching, or indeed the aspect of the previous signal? (assuming of course they are not 'overspeeding' towards a red)

 

[Lockwood]

If you go screeching to a halt then the signal back there that you missed was red?

Certainly not the most useful advanced warning.

The comment was made earlier about AOCL/ABCL. Would a line with a higher number of foot crossings/farm crossings also make you go "I'm going to ease off a bit, since I can't see the crossing as clearly" or stick with the usual "I'm approaching, I'm sounding my horn for the 3.0 seconds at the board, that's all that's needed"?

I understand that driving to signals rather than line of sight, and route knowledge, means you don't rely on what you can see to determine your driving, but are there bits which are made more difficult? Any more tension from the environment?

 

[QueensCurve]

“shooting the distants “

Please defiime that term for those who are unfamiliar with it.

 

[Deepgreen]

100mph max for me

Is that your personal choice or your TOC's directive?

 

[Ashley Hill]

Please defiime that term for those who are unfamiliar with it.

It’s a slang term referring to the bang from the exploding detonator placed on the rail when the distant signal is “on”.

 

[Deepgreen]

How does TPWS give a driver an indication of the aspect of the signal they are approaching, or indeed the aspect of the previous signal? (assuming of course they are not 'overspeeding' towards a red)

To be fair, the word used was "condition" rather than "aspect" - there is a subtle but important difference (i.e. any 'proceed' aspect or red). It can be assumed that the signals' aspects will follow the normal pattern, unless an emergency occurs that suddenly puts the next signal to red from, say, green (i.e. out of sequence), when it will make little to no difference whether it is foggy or not.

== Doublepost prevention - post automatically merged: 28 Dec 2024 ==

Is there any difference in Absolute Block signalling areas with semaphores for drivers or do they proceed as with other areas? I am of the impression that signallers of such places are required to report if specific siting points are not visible due to fog? So does this have implications for drivers?

Shouldn't that be 'sighting points'?

 

[craigybagel]

Is there any difference in Absolute Block signalling areas with semaphores for drivers or do they proceed as with other areas? I am of the impression that signallers of such places are required to report if specific siting points are not visible due to fog? So does this have implications for drivers?

You throw the brake in and get down to a speed where you know you can stop in the distance you can see ahead. You make sure you count your signals thoroughly so you know which is the section signal and the point you can return to line speed if green.

In a way AB can be easier for a driver because with the nature of that signalling you have to know exactly where every signal is. In a long section of 4 aspect colour light TCB you're less likely to know their location in that level of detail (except for the ones controlling junctions or that you stop at regularly)

Seriously though, doing line speed in thick fog is one of the most fun and satisfying things we get to do as drivers.

 

[Foxhunter]

Fog marking points,generally about 200 yds from the box. It was either a signal,structure or marker that when it could not be seen during fog then it was officially foggy and Fogmen were called out to repeat the distant signals to the drivers. If the distant was “on” a detonator was placed on the rail and the driver shown a yellow handsignal. If “off” the the detonator was removed and the driver shown a green handsignal.
I’m not aware of anywhere in this country where “shooting the distants “ is still carried out. It’s certainly not in the rule book anymore.

A small contribution from a heritage sector signalman. I was on duty last night and for the first time I was unable to see my fogging point (Up Main Starter). The box I was working has semaphores in the station area, but colour light Distants. Our Rule Book requires that I prevent the Distants from showing Green in this circumstance. Obviously with the speeds we operate at this is all a bit of overkill. The drivers' biggest problem with the conditions last night was maintaining adhesion on the damp rail. All rather good and atmospheric though, the more you exclude the modern intrusions from the scene, the more authentic it feels.

 

[Ashley Hill]

A small contribution from a heritage sector signalman. I was on duty last night and for the first time I was unable to see my fogging point (Up Main Starter). The box I was working has semaphores in the station area, but colour light Distants. Our Rule Book requires that I prevent the Distants from showing Green in this circumstance. Obviously with the speeds we operate at this is all a bit of overkill.

On the heritage line I signal on we extend our clearing points for acceptance when our fog markers are obscured.

 

[Steve Harris]

AWS, and more recently TPWS, give the driver an indication of the signal condition without being able to see it at all. Except in very extreme circumstances no signal should be more than one degree more restrictive then the previous one (so a green should only be followed by another green or a double yellow, for example). On the Underground there are tripcocks which should stop a train before reaching whatever obstruction a red signal is guarding.

That wouldn't be the case in some area's, which can only show green, single yellow, red. But the point your making still stands. (Knowing your previous aspect determines what to expect next and you adjust your speed accordingly).

 

[AverageJoe]

How does TPWS give a driver an indication of the aspect of the signal they are approaching, or indeed the aspect of the previous signal? (assuming of course they are not 'overspeeding' towards a red)

I was just about to ask him the same questions.
If the indication he is referring to is the spilling of coffee as the emergency brake is applied and the brake demand light flashing on the tpws panel then that is an indication I do not want!

 

[Archvile]

Full linespeed most of the time. Drop 10-20 mph approaching short signal sections that regularly display cautionary aspects. It really is as simple as, can you stop at the red signal if required. Route knowledge is king.

 

[officewalla]

I was out a couple of nights ago in fog so thick I couldn't see the rails along which I was travelling. Heightened senses and route knowledge are key. I drove normally most of the time but lost SA a couple of times so threw the brake on until I regained an indication of my exact location. It was only about 1 1/2 hours but my brain was working overtime and needed another hour or so (passing back) to calm back down to normal. Short answer is challenging but fun especially in the dark.

 

[Surreytraveller]

Please defiime that term for those who are unfamiliar with it.

I've never heard the term before, but it was explained in the post so I understood what it meant

 

[TreacleMiller]

As has been said, for me it's drive normally, paying extra attention to lineside signage that's unlit.

You can generally feel where you are by curvature, the sightings of the odd bridge and speedboard etc.

125mph with maybe 2 seconds of visibility isn't for the faint of heart and you certainly have to be on your toes.

That being said there was an area on my route that's been re-signalled with various signals moved and I think one or two extra added. Probably did about 75% of my normal speed through that section as I could not really be sure of where everything was.

I was also using the horn for a bit longer and warning before going through stations.