Safe Speed Forums

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Too much of our money is being wasted on supposed road safety improvements that are actually making driving more dangerous.

I think you are right Rod. There needs to be a method of ENSURING the train and road traffic cannot come into contact. I think your raise the road barrier may be a bit costly but how about those old hinged gates? Across the track to allow road traffic across, swinging across the road to allow the train through. Back them up with a full width raising ramp to positively stop road traffic and if the gate does not lock in place there is obviously an obstruction and the train is stopped.
The worrying thing is, there will be a group of people looking at this "accident" with the opposite intentions of safety, how easily the rail network could be disrupted. Scary!

I appreciate conditions were different in yesteryear - slower trains, fewer cars, etc. But... can anyone remember any accident involving a train at one of the manned level crossings with the gates that either blocked road or rail?

From what I have heard so far none of the suggestions for improved crossings would have helped. The train was about a mile away when the barriers came down. That doesn't give much time to move a vehicle out of the way and is not enough to stop a high speed train at full pelt.

There is a balance to be struck. If you drop the barriers too early then drivers get frustrated with the delay which leads to more people taking the risk of driving around or dodging under the barrier.

It seems like this collision may have been a deliberate, if so then the likelyhood of a repeat is pretty small, does it really justify spending billions building bridges at every level crossing?

[The worrying thing is, there will be a group of people looking at this "accident" with the opposite intentions of safety, how easily the rail network could be disrupted. Scary! [/quote]

I agree. This will probably bring the PC car-haters out in force. And as usual, all motorists will be blamed for one person's stupidity.

How many cars on level crossings would it take to cripple London? If it isn't going to be dealt with from the safety perspective, how about from the anti terrorist one. The w@*!**s don't even have to kill themselves to achieve this.

There are 8000 unmanned crossings in the UK. A terrorists paradise! Imaging the damage if it was a truck instead of a car...

I noticed the minister was back pedaling on safety when he was grilled on the news this morning. He kept saying 10 people per day are killed on the roads....WTF has that got to do with rail safety..

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Speed camera policy Kills

How many of those 8000 crossings are in towns? Put 20 000 liters of fuel in the truck? Who still thinks unmanned level crossings are still OK?

Unfortunately, there are no interconnected signal systems associated with this type of level crossing - a train approaching such a crossing may very well see nothing but green signals even if the barriers are up and road traffic is crossing the railway line. The barriers are dropped as the train passes a certain point on the track (the placement of this point being such that, travelling at the maximum line speed, a train would take at least 30 seconds to reach the crossing) and it is then assumed that the crossing will be cleared by the time the train arrives - hence the half-width barriers, providing an escape route for any vehicles already on the crossing when the barriers drop.

As events of last week showed however, if a vehicle does NOT move off the crossing for whatever reason, then there is no interlocking mechanism to set the rail signals to red. There will be a telephone at the side of the crossing so that the relevant signal box can be contacted, but that relies on the road user knowing/remembering that this exists, and then using it quickly enough to have the signals changed before any train gets too close to be stopped.

I wouldn't have thought the answer to this would be "all that many". AHBs tend only to be used on lines with low maximum speeds and/or where the road in question has low levels of traffic.



I think if a terrorist organisation wanted to cause mayhem in a busy town/city centre, they'd be better off simply driving said truck into a suitable spot and detonating it themselves, rather than relying on finding an AHB in a similarly suitable location and then waiting for the next high speed train to approach whilst remaining undetected by anyone who might be able to raise the alarm in sufficient time to stop the train.

Useful info there Twister, If the interlock is not there perhaps it shuld be. From the terrorist point of view what you suggest is technically difficult and can be "seen" during the planning stage. Put it this way, YOU couldn't do it, but given the sad inclination you could park a large quantity of fuel on a track within minutes of a train arriving. As with most crime prevention it's very difficult to stop the determined but you can deter the opportunist with simple, basic measures.

Problem is, if you put an interlock on the signalling and barriers, you then HAVE to have human monitoring of the crossing, and if you're going to have that then you can install full barriers. The next question is what do you do with all the occupation crossings (i.e. crossings on private roads/tracks, typically related to farms) which are usually protected only by a gate which is manually moved out of the way to allow road traffic to cross the line. It'd be prohibitively expensive to monitor all of these on a full-time basis, but providing a bridge/tunnel wouldn't be a cheap alternative either.



You mean the "drive a truck into the centre of town and blow it up" suggestion? I don't see how it's particularly difficult to rig up an explosive charge inside a fuel tank such that it can be triggered from the driving seat, and then to simply drive the truck through town looking exactly the same as any of the other trucks which drive through town, right up to the point where you hit the trigger.

On the other hand, using a level crossing and the subsequent collision with a train to deliberately cause a fuel-laden truck to explode in a suitably well-populated area to cause significant numbers of casualties seems like a very extravagant and over-complicated way of causing terror. I can see how the idea of randomly parking vehicles across unmonitored crossings might appeal to a terrorist mind from the fear and disruption it would cause - you'd have to set up monitoring of each crossing and in the meantime either close the line or greatly reduce the linespeed to give the train drivers a chance to stop if they saw an obstruction - but it doesn't strike me as being a particularly efficient way to cause casualties on a large scale, as your previous post seemed to be suggesting.



Actually, I suspect I almost certainly could do it. Figuring out the "best" time to be at the crossing isn't that difficult - passenger train timetables are public domain information, as is real-time running information. The difficulty with your idea is in finding a suitable crossing - remember that it has to be an AHB on a high speed line in or very close to a highly-populated area.


However, I hope you're right, because if terrorists start to use AHBs in this way, then they'll be a damn sight easier to stop than if they simply start driving truck bombs through populated areas on a random basis...

A report on the BBC Breakfast News on 8 November stated that the train survived the initial impact with the car. De-railment occured when the train came to a railway siding.

Anyway, during my driving test 20 years ago, I remember being asked a question about what to do if my car stalls on a level crossing.

Try to restart the car. If that fails, get everyone out of the vehicle. Phone the signalman and ask if there is a train approaching. If not, push the car clear of the crossing. If the crossing lights and bells start, leave the vehicle immediately and stand well clear of the crossing.

I seem to remember advice to deliberately start it in gear a few times to jerk it across on the starter motor (assuming that much still works), though I can't recall if this was from my driving instructor. Probably wouldn't do the car any good, but then neither does having a train hit it.

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Make everything as simple as possible, but not simpler - Einstein

Thankfully it's not that simple but I'm not going to start explaining the problems on here.

I was refering to you not being able to put together the above device, almost anyone can stick fuel on the track as you have made clear.

Not so, terrorism is not about killing people, it never has been, it's about using the threat and subsequent terror to make the target change it's mind. How much terror would be created if say 3 of the 8000 crossings had fuel filled vehicles left on them tonight, none blew up and no one was caught but the papers got the story? Terror created and mission achieved.

True, but then I don't have access to the same resources that terrorist organisations have. The simple fact is, terrorists all around the world can and do use explosive devices, so whether I as a member of the general public could pull off such an act is irrelevant.



It might not primarily be about killing people, but how many terrorist organisations - particularly those who seem most active in recent years - choose to conduct their activities with casualty minimisation in mind?



And how much terror would be created if those 3 fuel filled vehicles were replaced with, say, concrete filled skips?

I don't disagree with your thoughts on what effect it might have if terrorists started targetting level crossings, rather with your suggestion that they could use this technique to target built-up areas. For sure it's easier to park a fuel tanker on a level crossing than it is to rig it with explosives, but then you're limited by the locations of the crossings.

I am not sure if I have read this correctly or understood precisely what is being said.
Are you saying there is no fail safe signal to advise the train driver that the level crossing barriers are down thus preventing vehicle access across his path? Your post only says the train triggers the barriers to drop 30 seconds before it gets to the crossing then it trusts to luck as there is no feedback and no time to react!!
With the above in mind I am more concerned now than previously and the need for a flip up barrier to remove all obstructions on the line looks more necessary than ever. As a mechanical engineer I can assure all readers the cost of fitting such barriers to all fast track lines would be far less than the billions being talked about for bridges and tunnels and probably less than the disruption clean up and repair cost of this single incident. It is simple engineering using everyday materials and if designed correctly would be a common structure fitted to all common crossings. Batch production would bring the price down to less than 100,000 pounds per crossing still a 100 million pounds for a thousand crossings but the cost of this incident and the subsequent inquiry will be way over that.
RJ

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Too much of our money is being wasted on supposed road safety improvements that are actually making driving more dangerous.

Basically, yes. In effect, the crossing doesn't exist from the point of view of the signalling, so although route knowledge will let a driver know they're approaching a crossing, there's no specific signal indication that the crossing is there, that the barriers are lowered, or that there is nothing blocking the track.


Remember, if the barriers start to close with vehicles still on the crossing, they aren't trapped on the crossing - that's why the barriers only stretch halfway across the road. If you're travelling in a slow moving vehicle, you're supposed to call the signalbox first to let them know you'll be blocking the line for longer than usual. In queues of traffic, the crossing should be treated as a box junction (IIRC some crossings are marked as such) and you should wait behind the stop line until you know you have room to clear the crossing on the far side of the line. In normal traffic conditions, the 30s trigger period should be more than sufficient for a vehicle who's just started crossing to safely clear the far side of the tracks before the train passes.

This trust-based method of crossing protection falls apart in certain very specific circumstances.

1. a vehicle breaks down on the crossing, and there is insufficient time for the signalbox to be contacted and trains stopped.

2. an impatient driver deliberately swerves around the barriers after they've been lowered, too late to clear the crossing before the train passes.

3. a driver deliberately leaves their vehicle on the crossing.

Bear in mind that unmonitored crossings are generally only used on roads (public and private) where the level of traffic is usually very low, or on busier suburban roads where the maximum line speed is low and trains would have a good chance of stopping if the crossing were blocked. With the generally low levels of road traffic involved, case 1 is extremely unlikely - the vehicle would have to break down on a specific stretch of road within a specific time period. Case 2 is also unlikely - yes there are too many brainless drivers who think it's OK to play chicken with trains, but again there's just a short time window in which acting like a prick will actually result in a collision. Case 3 just isn't something you want to think about, even given the recent events. But even if we re-engineer every single level crossing to prevent this from happening, there are still ways for someone to get onto the tracks if they really want to, so whilst we might be able to stop case 3 from happening at level crossing sites, we wouldn't be stopping it from happening elsewhere on the network.


So yes, unmonitored crossings CAN be a threat to rail safety, but in the vast majority of cases only if road users choose to put themselves and the railway at risk. How far should we go to secure the rail network against acts of stupidity? How much tax revenue are we prepared to let the government sink into this? How big an increase in fares are rail users prepared to accept before they decide they're better off driving? What effect would this have on road safety...




In which case you'd need interlocked signalling to prevent the train from approaching if the flip-up barrier was still down, and you'd also need visual monitoring of the crossing so that the signalman could prove the crossing was clear before releasing the signal. Installing a full-barrier crossing would also provide these safeguards, using existing proven technology that the railways are familiar with. Now you need to ask yourself why the railways haven't already done this, and whether those same reasons would also apply to the introduction of any other protection scheme with similar resource requirements.

With modern technology and utilizing GPS the need for a signalman is removed. By simply having direct communication with the driver and he with the track situation ahead would be enough to provide a safer system. With the flip gates in the down obstructed situation the driver would be aware that 90 seconds ahead the track is blocked and he or the auto pilot system would apply the brakes thus stopping the 100mph train in 72 seconds. If the obstruction sensor cleared during the brake sequence the train would return to speed.
This whole problem is childs play to sensor and circuit up, I have apprectices in their first year working on more complex issues than this. No self respecting company would be so cavalier as the rail industry appears to be when hundreds of lives are at stake!!. This is no different than a fully loaded plane trusting to luck that the runway they are landing on is clear or trusting to luck that the sky ahead is clear to fly into. Luck playes no part in the air industry, communication and technology are put to work and the result is the safest form of transport available. The rail industry needs to take a look at the cost benefit equations and add in the unmeasureable personal costs to bereaved family and friends of those who die because someone trusted to luck on their behalf.
RJ

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Too much of our money is being wasted on supposed road safety improvements that are actually making driving more dangerous.

With modern technology and utilizing GPS the need for a signalman is removed. By simply having direct communication with the driver and he with the track situation ahead would be enough to provide a safer system. With the flip gates in the down obstructed situation the driver would be aware that 90 seconds ahead the track is blocked and he or the auto pilot system would apply the brakes thus stopping the 100mph train in 72 seconds. If the obstruction sensor cleared during the brake sequence the train would return to speed.
This whole problem is childs play to sensor and circuit up, I have apprectices in their first year working on more complex issues than this. No self respecting company would be so cavalier as the rail industry appears to be when hundreds of lives are at stake!!. This is no different than a fully loaded plane trusting to luck that the runway they are landing on is clear or trusting to luck that the sky ahead is clear to fly into. Luck playes no part in the air industry, communication and technology are put to work and the result is the safest form of transport available. The rail industry needs to take a look at the cost benefit equations and add in the unmeasureable personal costs to bereaved family and friends of those who die because someone trusted to luck on their behalf.
RJ

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Too much of our money is being wasted on supposed road safety improvements that are actually making driving more dangerous.