SPAD signals- Colour

[brad465]

I've never seen this signal type go off, and still in debate with myself and other sources asking- What colour do they show?

My current belief is white or red.

 

[ralphchadkirk]

I've never seen this signal type go off, and still in debate with myself and other sources asking- What colour do they show?

My current belief is white or red.

Two flashing red lamps, and a steady red lamp with 'STOP' written on it.

 

[swt_passenger]

I've never seen this signal type go off, and still in debate with myself and other sources asking- What colour do they show?

My current belief is white or red.

Three reds. Middle one steady, top and bottom flashing.

http://www.railsigns.co.uk/sect8page2/sect8page2.html

The Railsigns website reckons they are no longer being fitted, out of interest, indeed a set of three were removed last year at the London end of Southampton Central.

 

[brad465]

Thanks

 

[Railsigns]

This video on YouTube shows a SPAD indicator being activated:

http://youtu.be/xje3coP9-IM

Note that this is the earlier form of SPAD indicator. Later ones don't have "STOP" written across the middle lens.

 

[142094]

Video looks to show Shipley, think there is also one at Keighley and one just outside of Leeds station.

 

[TDK]

Three reds. Middle one steady, top and bottom flashing.

http://www.railsigns.co.uk/sect8page2/sect8page2.html

The Railsigns website reckons they are no longer being fitted, out of interest, indeed a set of three were removed last year at the London end of Southampton Central.

With the introduction of TPWS they are not really required any more

 

[swt_passenger]

With the introduction of TPWS they are not really required any more

So I heard a while back - they could apparently have been removed anywhere TPWS was fitted, but that would have increased the cost and timescales of TPWS too much, so they have basically been left until the next routine resignalling. Presumably in another 20 years or so they'll just be another historic talking point...

 

[TDK]

So I heard a while back - they could apparently have been removed anywhere TPWS was fitted, but that would have increased the cost and timescales of TPWS too much, so they have basically been left until the next routine resignalling. Presumably in another 20 years or so they'll just be another historic talking point...

Indeed - there are also SPAD AWS magnets in some locations - this is an extra AWS magnet sited directly next to a signal only active when the signal is at danger, I know of 2 - one is at Moor Street on P2 and the other is at Grand Junction where the Camp Hill line merges with the Stour in the down direction, there are many more maybe someone else could list a few more!

 

[MrC]

Indeed - there are also SPAD AWS magnets in some locations - this is an extra AWS magnet sited directly next to a signal only active when the signal is at danger, I know of 2 - one is at Moor Street on P2 and the other is at Grand Junction where the Camp Hill line merges with the Stour in the down direction, there are many more maybe someone else could list a few more!

London Waterloo springs to mind (except maybe the international platforms?).

 

[Railsigns]

Heath Low Level: TPWS + Additional AWS + SPAD Indicator:

 

[Pacerpilot]

So I heard a while back - they could apparently have been removed anywhere TPWS was fitted, but that would have increased the cost and timescales of TPWS too much, so they have basically been left until the next routine resignalling. Presumably in another 20 years or so they'll just be another historic talking point...

When Port Talbot East was resignalled in 2007, a new SPAD indicator was installed at Margam at the start of the new Bi-Directional line...

Heath Low Level: TPWS + Additional AWS + SPAD Indicator:

Note the plunger cabinet next to the signal post. The Driver operates the plunger when required to pass HJ12 at Danger, to prevent the SPAD indicator from illuminating.

 

[deltic1989]

I could be totally wrong here but it looks like new SPAD indicators have appeared at Newark flat crossing. They could have been there years but i only noticed them on my last trip and the posts look quite shiny and new.

 

[wensley]

I could be totally wrong here but it looks like new SPAD indicators have appeared at Newark flat crossing. They could have been there years but i only noticed them on my last trip and the posts look quite shiny and new.

There have been SPAD indicators for D81 (Down Fast) and D85 (Down Newark / Lincoln) in place for some time Hope that helps!

 

[Kneedown]

I've never seen this signal type go off

Thats always a good thing!

 

[driver9000]

There are SPAD indicators at Leeds unless they have been removed since I was last there. Morecambe South Junction has one coming off the Morecambe line onto the WCML.

 

[brad465]

Thats always a good thing!

How? hock:

 

[ainsworth74]

How?

Because if it did go off then the driver has just passed a signal at danger! Something which is normally considered to be a very bad thing to happen!!

 

[ralphchadkirk]

How? hock:

Not seeing a SPAD indicator going off is a good thing, because it means your train hasn't passed the signal in order to trigger it! (Unless of course you're authorised past).

 

[Hydro]

http://www.youtube.com/watch?v=xje3coP9-IM

Short RT film about SPAD indicators.

 

[swt_passenger]

http://www.youtube.com/watch?v=xje3coP9-IM

Short RT film about SPAD indicators.

Posted yesterday though, so that one must be a repeater for anyone who ran through the thread too fast without stopping at the appropriate place!

 

[Hydro]

Posted yesterday though, so that one must be a repeater for anyone who ran through the thread too fast without stopping at the appropriate place!

 

[Kneedown]

Not seeing a SPAD indicator going off is a good thing, because it means your train hasn't passed the signal in order to trigger it! (Unless of course you're authorised past).

In addition, a SPAD indicator will also activate if a train on another line that conflicts with your line has a SPAD.
Also not a good thing to happen!

If you are authorised past the signal there is normally a plunger to press to override the SPAD indicator.

 

[brad465]

Not seeing a SPAD indicator going off is a good thing, because it means your train hasn't passed the signal in order to trigger it! (Unless of course you're authorised past).

Oh yes! However, even though this is bad, surely if the train affected is going the other way then it's not always a problem to you. I'm guessing the situation on the video was just a demo of what happens, so no-one there was affected.

What happens if these signals aren't working properly?

 

[Tomnick]

However, even though this is bad, surely if the train affected is going the other way then it's not always a problem to you.

It would still be a problem to you - the required immediate action is to chuck the brake in regardless of what any other train might appear to be doing, and then probably arrange for a change of trousers.

What happens if these signals aren't working properly?

Normally, a defective signal would (depending on the nature of the interlocking and the defect) prevent the signal in rear clearing. Not sure whether SPAD indicators are proved in order, but what's the chances of it failing on the rare occasion that it's required...?

 

[O L Leigh]

In addition, a SPAD indicator will also activate if a train on another line that conflicts with your line has a SPAD.
Also not a good thing to happen!

I've said this before but it seems never to stick in people's minds.

Taken from here. A SPAD-I is a SPAD indicator.

SPAD-I's are usually positioned at locations where there is a risk of a SPAD resulting in a collision. Therefore they might be seen on approach to single-line sections or at converging junctions where a train SPAD-ing the protecting signal could reach a point of conflict with another train.

Although TPWS has reduced the chance of a SPAD resulting in a collision, SPAD-I's are still necessary. This is because they are usually installed in pairs or even sets and will apply to all other lines where trains are travelling towards a point of conflict. Therefore if a train SPAD's the protecting signal it will set off all the SPAD-I's in that set to alert drivers of other trains to the danger. Even if a driver is running on greens, if he/she sees a lit SPAD-I the train must be stopped immediately and the signaller contacted.

O L Leigh

 

[MrC]

Although TPWS has reduced the chance of a SPAD resulting in a collision, SPAD-I's are still necessary. This is because they are usually installed in pairs or even sets and will apply to all other lines where trains are travelling towards a point of conflict. Therefore if a train SPAD's the protecting signal it will set off all the SPAD-I's in that set to alert drivers of other trains to the danger.

Not sure how they're still necessary to be honest. TPWS gives the same protection as SPAD-Is with the difference that the visual aspect isn't required. Anyone SPADing in such an area will set all signals back to danger (same as for the SPAD-I scenario) and activate the TPWS trigger loops. With SPAD-Is you also have a slight delay for the AWS timeout plus there's the real risk of a driver simply cancelling the AWS out of habit and continuing without stopping - especially where a single SPAD-I covers multiple lines and may not be in the driver's direct line of vision or simply doesn't exist in the AWS-only installations as listed above. I'm pretty sure that there's a few drivers that when coming out of London Waterloo are unaware of the SPAD-I installation and would simply cancel and continue wondering why the AWS has gone off.

The only possible benefits I can see with SPAD-Is are in the marginal cases such as where a SPAD occurs after another driver has already passed over the SPAD-I AWS ramp but the indicator is still in the driver's field of vision, or a driver is on an adjacent non-signalled line but can still see a SPAD-I.

 

[swt_passenger]

The multiple SPAD-I set up at Southampton (as shown in the video) has definitely been removed during the recent re-interlocking though, as I pointed out earlier - so O L Leigh's reasoning must have exceptions...

 

[hairyhandedfool]

TPWS doesn't guarantee the train will stop in the overlap provided (I believe the statistic is that trains travelling at over 70mph will not stop in time). A driver reacting correctly to a SPAD Indicator, should enable a potential incident to be less severe than it otherwise would be, a TPWS activation alone would give no warning to drivers of other trains.

My recollection of the rulebook is that if a driver sees a SPAD indicator lit they MUST stop their train immediately (i.e. it doesn't need to refer to your line).

It could be possible that where the linespeed in a TPWS fitted area is significantly lower, thus allowing TPWS to stop the train before a collision could occur, SPAD indicators may not be needed.

 

[brad465]

Are most SPAD indicators in locations where trains will be travelling slow (i.e. a main station)?