Driving styles with flashing yellows

[O L Leigh]

This is where a driver's route knowledge comes into play and one of the main reasons why there isn't one simple answer to the question.

Take your point about whether the route was set up at all. As it happens, I was just thinking of times when I've been having a peek out of the window and the route was set well in advance, i.e. the flashing double yellow was seen.

With respect, you will almost never have as good a view along the line of the signalling ahead from inside the train than the driver has from the front. You may be able to see the signals flashing, but the driver will have seen them first and they may not have been flashing when they first came into view or, indeed, until the train had got quite a bit closer to them.

But again, there is a difference between "reactive braking" due to signalling and "planned braking" where you expect a reduction in speed, as I hinted before. Signalling enforces a rate of deceleration that may not be optimum whereas route knowledge means that you can choose for yourself where to brake.

Anyway, that's enough of all that.

O L Leigh
--- old post above --- --- new post below ---

Is this talk of passing the flashing double yellow at a reduced speed a defensive driving issue based on the driver knowing that the train is taking the diverging route before the signal comes into view? If so can somebody explain exactly what the safety benefit is? It seems to me that to bring the issue of a divergence into the driver's mind at this point may create an expectation of the normal junction signal sequence and hence increases the risk of a SPAD if the junction signal fails to release from single yellow. It is also slowing the train unnecessarily early, something the flashing aspect sequence is trying to avoid.

I think I covered this adequately. You have to drive to the signalling you can see in front of you. You hope that the junction signal will clear to a less restrictive aspect but you can never assume that it will. That would be career suicide as it invites a SPAD or, at the very least, a heavy stop.

But I can assure you that it is still faster than approach control that brings a train almost to a stand at the junction signal. As I mentioned, it's down to route knowledge. You know in your mind what the speed across the junction is and where the next red signal will be (based on the aspects you can see). Therefore you brake and control the train speed accordingly. This is commonsense as I'm sure you can agree.

O L Leigh

 

[fordylad]

There is also the small matter of TPWS+ to consider . The aim of the game, of driving trains is to do it as safely and comfortably as possible. Nobody will thank you for racing towards a restrictive aspect. & anyway if the bobby is slowing you down or stopping you. It's Network Rail's time not FGW.

 

[cjmillsnun]

Wasn't there an incident at the junction being discussed where a driver did assume the signal would clear and ended up passing the following signal at red?

Edit: Yes, there was. RAIB

I think Colwich was a similar type of accident in the BR days.

EDIT also some bad maths by the original OP..

Just because the braking distance of xMPH is that much more than the slower yMPH, does not mean that it'll take the difference of the two braking distances to brake from x to y. That is very often not the case as you will find that the initial speed is scrubbed off fairly quickly but as the friction material heats up, it chemically changes and a gas is released that will inhibit retardation. It's a phenomena known as brake fade.

Also the figures given will be for emergency braking. Not something anyone wants to use in regular service, as it is neither efficient nor comfortable for passengers.

 

[driver_m]

Very interesting reading the reactions to what some people have said on this thread. Its not really possible to have a technique as there is so much variance. for instance I encounter flashing yellows for a 15mph junction and many at 70/75. I'd just like to ask this question. Speed is 40mph and you encounter flashing yellows, for a junction set at 45mph and also a speed increase of 60 and 100 on the mainline. I'd be interested to see what people think should happen in this situation.

 

[TDK]

Very interesting reading the reactions to what some people have said on this thread. Its not really possible to have a technique as there is so much variance. for instance I encounter flashing yellows for a 15mph junction and many at 70/75. I'd just like to ask this question. Speed is 40mph and you encounter flashing yellows, for a junction set at 45mph and also a speed increase of 60 and 100 on the mainline. I'd be interested to see what people think should happen in this situation.

Stick at 40mph as the PDP for many companies quotes not to use more than 50% power after passing a restrictive aspect.

 

[railuser007]

Slightly off topic but on lights - why do XC Voyagers have one of their 'head lights' at full beam in day light when comming into the station - I've seen this especially at Birmingham New Street quite a lot?

 

[A-driver]

Slightly off topic but on lights - why do XC Voyagers have one of their 'head lights' at full beam in day light when comming into the station - I've seen this especially at Birmingham New Street quite a lot?

Same on all trains and train headlights don't have different beam strengths, just on or off. Older trains have one headlight on all the time, day or night. Newer trains have 2 headlights, the one under the driver is lit during night time, the other side is lit during the day.

If one fails then the other sides light will be used instead.

 

[Crossover]

Slightly off topic but on lights - why do XC Voyagers have one of their 'head lights' at full beam in day light when comming into the station - I've seen this especially at Birmingham New Street quite a lot?

It has been covered elsewhere, but only one of the main headlights is on at a time. During the day, it is the one on the right, mainly there for making the train more visible to anyone in the vicinity (and I believe to avoid dazzling passengers at station platforms which are commonly on the left of approaching trains)
During hours of darkness, it is the left one which is used, there to give more illumination of the cess side of the train and the reflective signs that are positioned there

 

[hairyhandedfool]

I think Colwich was a similar type of accident in the BR days.....

The rules for flashing yellow approach weren't exactly the same then, they were amended afterwards, but the driver apparently assumed a signal would change, it did not, he realised too late and couldn't stop the train before a collision occurred.

 

[TOCDriver]

Assumptions are a very dangerous thing when it comes to driving trains. never assume anything