Chasing signals

[bionic]

This is one of the times where the job really is as easy or difficult as you want to make it.

You can ease off and roll about catching the greens at a nice steady speed, easily able to stop if you start slipping.

Or, you can dash about, cancelling magnets and running upto reds, massively increasing your risk, maybe clawing back a few seconds which no one will thank you for.

When you’re on restrictive aspects get the brake in, you’re on the signallers time from that moment, not yours.

I remember the old grizzled “worked my way up from BR traction Trainee to second man to relief Driver in the good old days,” instructor used to keep telling me:

“F*@!k ‘em, if they want you to go fast they can give you green signals.”

Spot on post.

 

[ComUtoR]

You'd support it if it "adds to your job" or "helps reduce my workload" (my bolds) - mutually-exclusive, surely?

The more advanced trains get and the more complicated they become isn't always beneficial. Lets take a 700 compared to older stock.

No hill start/automatic parking brake. I kinda like it but it has problems. It has a replaced a mechanical button in the cab but it leads to some complacency because the unit will still roll back. It has eliminated an operational incident but potentially created another. Overall I think its a good technological step forwards and provides a benefit. I still have to manage it and still have to use it properly and you need to learn a few more things and deal with a new fault etc but yeah, it adds to my job and adds a benefit to the unit. It has little impact on my workload.

MASDO/FASDO. (selective doors) This is like above. It has many benefits but it has caused just as many problems. There are some workload elements that have been reduced and some risk reduced but you still have to keep a close eye on it and it isn't as reliable as people believe.

HMI/DMI (machine interfaces) Basically they are Mitrack on steroids. They offer many advantages and are a benefit. They make fault finding easier and provide lots of great information.

PIS (onboard announcements) I remember when we got out first automated announcements. They are really good at reducing workload as you can input a code and the rest is taken care of. Having to make announcements over and over because more of a distraction. The current iteration seen in a 700 needs to be dropped into a volcano. A classic example of poor implementation of technology and one providing a solution looking for a problem.

Driver aids are good and can be a benefit but just as much, they can cause problems. There is an old adage about 'amps and air' and in some respects its right. Do we need more and more technology crammed into new trains which have little impact on how the unit is driven. If you put an 'advisory' system in the train that can be ignored and that many are already planning to ignore it why do it ? How much will the system cost to how much will it save ? Will it potentially introduce more risk and contribute to an incident ?

Keeping it tenuously on topic... The reason, as has already been mentioned, is that we drive defensively and don't 'chase signals' is because we are mitigating risk. With DAS/CDAS, from what I hear, it is almost dictating how to drive and what speed you need to do it at. I would like to think that all that training and experience should count for something when you are at the sharp end.

As I have mentioned and has been discussed before. ATO (automatic trains) will drive straight up to the Red at quite a lick before it sticks the brake in and it is much more aggressive than a human (because we are risk adverse) ATO will effectively 'chase signals' Will CDAS, knowing what's in front, do the same ?

 

[Johncleesefan]

There's a really easy trick to teaching it

Haha yes true.

 

[Deepgreen]

Let's put this to bed shall we.

I answered the question, in full, with a specific example and giving good description of how and why it happens as well as posting the advice for the Trainee. (feel free to confirm that with the OP)
The OP responded with a thanks, that's why it's there.
Then the forum formatting swallowed the post (posting on a phone is a total drama lama)
Then bionic replied with another explanation.
Then, because the information was already out there and the discussion was/is continuing. I don't see the point in reposting the same information for the umpteenth time.

There must be some confusion because; post 1 asks the question, post 2 is yours referring him/her to his/her trainer, but also including a quote of his/her thanks, which doesn't actually appear until post 3! Something's awry here.
As an aside, why does your statement about the "death knell of the guards" say that the forums rejoiced? I only ask because my reading of the huge number of posts on the issue gives me the strong impression that this forum, at least, is strongly in favour of guards. Just curious.

 

[ComUtoR]

There must be some confusion because; post 1 asks the question, post 2 is yours referring him/her to his/her trainer, but also including a quote of his/her thanks, which doesn't appear until post 3! Something's awry here.

Exactly. They thanked me for providing the information; which I did.

I discovered something weird when you press 'edit' If you are editing your post. You cannot insert a quote. My intent was to append the thanks directly under my post; hence why the quote is located under my text. So I used an old forum trick to start a new post, insert the quote and then cut and paste it into the original. As I said, the forum then proceeded to swallow the formatting. All exacerbated by using a mobile to do it with. A bit like when you get that annoying must have at least 5 characters message. Or when you have a post that saves the draft and you can't get rid of it unless you delete the entire thing, log out, clear your cache ad then log back etc.

Feel free not to believe me. I'm sure there is a post history in the back admin etc or you could just ask the op yourself. I can assure you the information was given out.

 

[Deepgreen]

Exactly. They thanked me for providing the information; which I did.

I discovered something weird when you press 'edit' If you are editing your post. You cannot insert a quote. My intent was to append the thanks directly under my post; hence why the quote is located under my text. So I used an old forum trick to start a new post, insert the quote and then cut and paste it into the original. As I said, the forum then proceeded to swallow the formatting. All exacerbated by using a mobile to do it with. A bit like when you get that annoying must have at least 5 characters message. Or when you have a post that saves the draft and you can't get rid of it unless you delete the entire thing, log out, clear your cache ad then log back etc.

Feel free not to believe me. I'm sure there is a post history in the back admin etc or you could just ask the op yourself. I can assure you the information was given out.

Why would I not believe you? What a strange thing to say. There are several eccentricities in the forum's programmes.

 

[whhistle]

Reminds me of Train Simulator's "Riding the Yellows".

 

[m25]

Chasing signals, basically your following a train in front, whereby your running under cautionary aspects up to reds expecting them to clear as the train in front clears the section in front.
Never a very good idea as the wonders that are the Power boxes might keep a signal at danger for any number of reasons. but as your expecting them to clear. significantly increases the chance of a SPAD or at the very least a clean pair of undies

Hope that helps

Thanks for your explanation.

 

[Ken H]

Chasing signals, basically your following a train in front, whereby your running under cautionary aspects up to reds expecting them to clear as the train in front clears the section in front.
Never a very good idea as the wonders that are the Power boxes might keep a signal at danger for any number of reasons. but as your expecting them to clear. significantly increases the chance of a SPAD or at the very least a clean pair of undies

Hope that helps

There is also the issue of approach control. that is when a signal protecting a speed restricted turnout is held at a restrictive aspect until the train is almost at the signal then clears. the idea is the train has reduced speed for the signal so when it clears, it wont take the turnout at too fast a speed. This becomes an issue then the driver assumes the signal will clear for the straight route and drives assumes it it will clear like the signal behind, but is caught unawares when it clears with a feather for a 'weave' or a diversion.

 

[Tomnick]

There is also the issue of approach control. that is when a signal protecting a speed restricted turnout is held at a restrictive aspect until the train is almost at the signal then clears. the idea is the train has reduced speed for the signal so when it clears, it wont take the turnout at too fast a speed. This becomes an issue then the driver assumes the signal will clear for the straight route and drives assumes it it will clear like the signal behind, but is caught unawares when it clears with a feather for a 'weave' or a diversion.

I’m not sure why the driver would be anticipating the signal clearing for the straight route. It’d normally be clearer already? The issue there is when the driver’s booked to take the diverging route, knows that the signal’s approach released for that route, assumes that it’ll clear at a certain point as it always does, and isn’t at all expecting to have to stop at it. One day, it doesn’t clear, because it’s being held at danger for some reason, and the driver can’t stop in time...

 

[Ken H]

I’m not sure why the driver would be anticipating the signal clearing for the straight route. It’d normally be clearer already? The issue there is when the driver’s booked to take the diverging route, knows that the signal’s approach released for that route, assumes that it’ll clear at a certain point as it always does, and isn’t at all expecting to have to stop at it. One day, it doesn’t clear, because it’s being held at danger for some reason, and the driver can’t stop in time...

Ah. maybe thats it. I remember Alan Williams talking about this in modern railways many years ago. Thanks.
he was saying that signals should not be used for speed control and was advocating splitting distants, I think.
I dont know if TPWS has fixed that.

 

[DanDaDriver]

I’m not sure why the driver would be anticipating the signal clearing for the straight route. It’d normally be clearer already? The issue there is when the driver’s booked to take the diverging route, knows that the signal’s approach released for that route, assumes that it’ll clear at a certain point as it always does, and isn’t at all expecting to have to stop at it. One day, it doesn’t clear, because it’s being held at danger for some reason, and the driver can’t stop in time...

That’s why, “there’s no such thing as approach control.”

 

[Bald Rick]

That’s why, “there’s no such thing as approach control.”

On my first ever cab ride, the driver was being assessed. As we approached a slow speed diverging junction, which we expected to take, and which was used by about 4 trains a day, the signal held at danger for approach control. The driver said to the assessor “I always take this one as a red”. I know what he was trying to say, but what I inferred was that there were some reds that he didn’t “take as a red”!

 

[Tomnick]

Ah. maybe thats it. I remember Alan Williams talking about this in modern railways many years ago. Thanks.
he was saying that signals should not be used for speed control and was advocating splitting distants, I think.
I dont know if TPWS has fixed that.

There's certainly some benefits to using splitting distants (or flashing yellows), but there's limits to what you can achieve with them, especially in complex areas with numerous divergences and various different speeds. TPWS doesn't do much to help other than mitigating against the risk if the driver does get it wrong!

That’s why, “there’s no such thing as approach control.”

So they say. Then you take a wrong route, booked over the diverging route but you end up going straight on under clear signals, and they say you should've known that you'd been wrong routed when you didn't get two yellows at the second signal in rear, because you know that the junction signal is approach-controlled .

 

[DanDaDriver]

So they say. Then you take a wrong route, booked over the diverging route but you end up going straight on under clear signals, and they say you should've known that you'd been wrong routed when you didn't get two yellows at the second signal in rear, because you know that the junction signal is approach-controlled .

Well yes. The driver is always to blame you know

 

[Taunton]

I remember Alan Williams talking about this in modern railways many years ago. he was saying that signals should not be used for speed control

There was a serious accident on the Toronto Subway due to this. They used time-released signals extensively for speed control on plain line, to the extent that drivers routinely approached reds at the required speed. As the trains had a window alongside the driver, passengers could observe this. The red would change to green fractionally before it disappeared from view, and this seemed to be how they were taught. There were tripcocks which - supposedly - gave protection in case it didn't clear. The accident train driver did not notice, as a couple of signals passed from view, that they were not actually clearing, and separately the tripcock on the train was misaligned and just missing the lineside trainstop. Collision at speed with a train ahead.