Effect of fog on railways?

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FordFocus

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Still drive normally in fog. Possibly brake earlier because of poor railhead as mentioned before.

The LED signals that burn your eyes out are actually useful during fog compared to the older filament lamps.
 
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ExRes

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This wasn't true for me on Sunday morning when it was foggy. I was trying to get from Three Bridges to Hassocks and ended up waiting 10-15 minutes longer for a train than expected. The delay was sufficient that the train due after the one I intended to catch turned up first. Whether that delay was due to the fog or something unrelated I don't know, there was only one other train delayed at that time according to the information monitor.
I'm not sure how often you travel on the BML on sundays, but if it's very often then you should know that there are a million reasons given for delays and very few true ones, I very much doubt that fog would have had the slightest reason for just one or two delayed trains, just as likely that someone was trying to get their broken down veteran car to Brighton by train ......
 

Tim R-T-C

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Train delayed because crew late arriving due to fog?

Happens a lot in snow. Trains are fine but crew stuck on roads!
 

Bald Rick

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No one had mentioned fog working yet, which surprises me. Much less prevalent now, but still applies in areas of Absolute Block.

Every manual signal box with absolute block has a marker, and if the signaller can't see it, then fog working is implemented. Effectively this requires a train to be clear of his/her section before a train can be accepted into the section in rear, ie trains are kept a minimum of two block sections apart rather than just the one. This reduces capacity, and on busier lines, this means that delays will happen to a following trains whilst the first train clears the (two) sections ahead.

This is done to mitigate the consequences of a SPAD, albeit TPWS does this very well now.

Exactly the same principle for poor visibility in falling snow, except it's then called snow working.
 

lazydragon

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Another benefit of driving a train instead of a car in fog is that you don't have (that many?) idiots driving with a full beam instead of dipped headlights, not improving their visibility and making the whole experience slower for all.
 

thenorthern

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Talking of Fog while I was on the train today at a station in thick fog the driver stopped short of the platform which I think was due to poor visibility.
 

cjmillsnun

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Fog is what AWS is for.
You get an audio indication of the signal ahead, whether you can see it or not.
Writing this sitting in Newport station, on time despite 140 miles of thick fog through the mostly manually-signalled Marches route from Chester.
Impressive.
Not so. AWS is a driver aid, not something to take over proper sighting of signals. A horn indicates either a caution proceed or danger. The only sound you can be 100% certain of is the bell (or bing) for a green.

Driving in fog relies more on the driver's route knowledge.
 

A-driver

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Talking of Fog while I was on the train today at a station in thick fog the driver stopped short of the platform which I think was due to poor visibility.

Sounds more likely to be to do with poor adhesion. The driver would know they weren't in the station due to being able to see that there was no platform there!

Sounds like the wheels locked up so he went into emergency and so was unable to release the brake again until the train had stopped.
 

Mugby

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Don't forget that fogs used to be very much worse than they are today, when almost every home in Britain had a coal fire and there were large numbers of factory chimneys etc.

In the days when many lines had no form of automatic warning, signalmen would call upon the services of fogsignalmen (from the P/Way dept.) to put one detonator on the line at a distant signal if it wasn't off when a train approached.
 

driver_m

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Have we not got any signallers on here? Absolute block requires a clearance point which is affected by fog as mentioned above, but varied dependant on whatever the type of signal was i.e colour light distant or semaphore distant. A semaphore distant required a line clear to next box in fog. That was old info and I don't know if that's changed.

As for the driving, the only thing that worries me about fog is what the general public are doing on stations and in general. A set of earphones cause enough switch offs in good weather!
 
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matchmaker

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No one had mentioned fog working yet, which surprises me. Much less prevalent now, but still applies in areas of Absolute Block.

Every manual signal box with absolute block has a marker, and if the signaller can't see it, then fog working is implemented. Effectively this requires a train to be clear of his/her section before a train can be accepted into the section in rear, ie trains are kept a minimum of two block sections apart rather than just the one. This reduces capacity, and on busier lines, this means that delays will happen to a following trains whilst the first train clears the (two) sections ahead.

This is done to mitigate the consequences of a SPAD, albeit TPWS does this very well now.

Exactly the same principle for poor visibility in falling snow, except it's then called snow working.
As the old joke used to go - "Call out the fogmen". "THE FOGMEN!"
 

notadriver

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I once had a guard pop his head through the door while I was doing 90 through the fog in darkness. You can't see anything ! Not much I said. Sod that he said and closed the door [emoji3][emoji3]
 

infobleep

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When did fog signalmen die out? They are certainly mentioned in my 1947/48 Southern Railway server weather warning booklet. It lists all the times they are suppose to be on duty and the signal box opening and closing times.
 
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Jala_150

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Last night was my first turn of duty since passing out as a driver, and also my first time driving in thick fog. Was a little nervous not having a mentor next to me, but like others have said I signed that I'm competent to drive the route. Kept to linespeed, although I did put the brakes on extra early for a couple of stations and only 2 minutes late at my destination which I was happy with. Route knowledge is invaluable during poor visibility.
 
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ComUtoR

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Kept to linespeed, although I did chicken out act professionally and put the brakes on early for a couple of stations, and only 2 minutes late at my destination which I was happy with. Route knowledge is invaluable during poor visibility.
Corrected that for you.
 

cin88

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Last night was my first turn of duty since passing out as a driver, and also my first time driving in thick fog. Was a little nervous not having a mentor next to me, but like others have said I signed that I'm competent to drive the route. Kept to linespeed, although I did put the brakes on extra early for a couple of stations and only 2 minutes late at my destination which I was happy with. Route knowledge is invaluable during poor visibility.
Talk about being thrown right off the deep end.
 

TDK

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I had a passenger ask me on Sunday why don't you slow down in the fog? I just said I didn't need to as I know where I am. They said they thought I should have in case a car was on the track. I just shrugged and carried on with my changing ends procedure, but it did make me think a little of driving in fog and obstructions on the line. The visibility on Sunday night on my patch was no more then 50m.
 

ComUtoR

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I was thinking the exact same when I corrected Jala's post. Fog is an experience thing. I'm pretty sure that a car won't be on the track on the Catford Loop.

Obstructions on the line are thankfully a relatively rare occurrence. If it was fog and high winds I'd be looking for trees and branches on our greener routes. I'm more cautious at our foot crossings and will sound the horn for longer and closer. Experience and professionalism dictates my actions and Driving style.
 
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A-driver

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I had a passenger ask me on Sunday why don't you slow down in the fog? I just said I didn't need to as I know where I am. They said they thought I should have in case a car was on the track. I just shrugged and carried on with my changing ends procedure, but it did make me think a little of driving in fog and obstructions on the line. The visibility on Sunday night on my patch was no more then 50m.

When I pass trough Hatfield non stop at 100mph I'm going round 2 blind and very tight bends. If something was on the track round one of those bends then by the time I had seen it, reacted to it and the brake had had a chance to bite I'd have hit it, most probably at over 90mph still.

I can't see the difference with the fog. A railway line should be clear for trains, that's why we take red signals so seriously. If there is any doubt that the line is clear then a driver will be cautioned in which case things like fog will play a huge part in how the driver judges the safest speed to proceed.

A car shouldn't be on the line and so I don't see any need to slow up in poor visibility any more than I do at night or going round bends or through tunnels.
 

FordFocus

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If I see something on the track by the time the brake res is fully charged to it's maximum pressure I would have hit the object. It will be slightly lesser speed of 100mph than if I was in fog but the object still would have been hit.
 

lincolnshire

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Main affect is on passengers - no view
Think you will find that you might as well not bother with windows these days as most spend there time looking at television catch up on computers, tablets and phones or playing games on there phones etc. Very few seem to ever look out of the windows these days.
 

cin88

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I had a passenger ask me on Sunday why don't you slow down in the fog? I just said I didn't need to as I know where I am. They said they thought I should have in case a car was on the track. I just shrugged and carried on with my changing ends procedure, but it did make me think a little of driving in fog and obstructions on the line. The visibility on Sunday night on my patch was no more then 50m.
Yeah I had less than 20m on sunday driving my car home from work. Even in a car, route knowledge saves your bacon when visibility drops. I'd hate to be going down an unfamiliar route in adverse conditions, I suppose that makes it a very good thing that train drivers have to know their routes like the back of their hands.
 

A-driver

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Yeah I had less than 20m on sunday driving my car home from work. Even in a car, route knowledge saves your bacon when visibility drops. I'd hate to be going down an unfamiliar route in adverse conditions, I suppose that makes it a very good thing that train drivers have to know their routes like the back of their hands.

Yes, but as I say above, you always drive your car at 'caution', ie you should always be able to top within the distance you can see. So you slow for bends incase someone has broken down round the blind curve etc and will therefore slow down when weather conditions affect visibility.
 

cin88

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Yes, but as I say above, you always drive your car at 'caution', ie you should always be able to top within the distance you can see. So you slow for bends incase someone has broken down round the blind curve etc and will therefore slow down when weather conditions affect visibility.
A point I don't dispute for one second. I was just trying to draw a paralel between train and car driving for bad visibility.
 
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