Train Derails in Scotland

[beast66606]

http://news.bbc.co.uk/1/hi/scotland/glasgow_and_west/10251545.stm

 

A train has derailed with both its two carriages "precariously balanced" over a 15-metre embankment, firefighters have said.

 

Crews are working to gain access to the carriages of the Glasgow to Oban train which is on fire.

 

The crash happened just before 2100 BST near the Falls of Cruachan, Argyll and Bute.

 

A number of ambulances are at the scene and the service said those injured were walking wounded only.

 

One witness reported that the train had shuddered to a halt and caught fire.

 

British Transport Police said all 60 passengers had got off the train and there were no serious injuries reported.

 

A spokesman said: "The train involved was the 1820 hours Glasgow Queen Street to Oban service. This is a two-car train and the leading car has derailed and caught fire.

 

"All passengers have been safely taken off the train, but the leading car remains overhanging the road.

 

"British Transport Police, Strathclyde Police and emergency services are attending the scene."

 

Strathclyde Fire and Rescue Service said there was a "major deployment of fire crews and appliances".

 

These included a major incident unit from Clydebank and heavy rescue vehicle from Easterhouse.

[Dagworth]

Reported on DEMU forum as being 156499 on 1Y27 Queen Street-Oban and that it struck a rockfall.

 

Andi

 

 

[Gwiwer]

Falls of Cruachan is not an easy place to access the railway. That is the section with trip-wired semaphores which should protect the line against a rock fall. It would appear this didn't happen or that it may have occurred beyond the protected section. I'm also making an educated guess that if the unit has caught fire this is somehow down to ignition of the fuel.

 

Pleased to hear that the train has been safely evacuated with only minor casualties.

[scotcent]

There have been occasional minor derailments due to rockfalls in this area over the years, despite "Anderson's Piano". The speed limit is fairly low (30 mph?) and accidents have never been major. Although the line is a stone's throw from the main Oban road, it's a good deal higher, and the terrain is fairly precipitous. I'm glad the passengers were safely evacuated, but it might have been a bit of a hike for them to access the road, and I'm sure some of them would have missed the ferry to Mull. If the road has to be closed as well the disruption will be considerable -- There's only one road through the Pass of Brander.

 

Allan

[Jamie]

If the road has to be closed as well the disruption will be considerable

Signs on the A82 at Alexandria this morning warning the A85 is closed somewhere about Dalmally. Whether related or not I don't know.

[Gwiwer]

Signs on the A82 at Alexandria this morning warning the A85 is closed somewhere about Dalmally. Whether related or not I don't know.

 

Traffic Scotland reports that the Pass of Brander is closed. The only available diversion is around the A82 / A828 via Ballachulish adding about 30 miles and around 45 minutes to the road trip. This would be to permit emergency service to access and work at the site and for recovery to take place. After that any rock fall would need to be made safe before the road and railway can reopen.

 

Rail replacement buses also need to follow this diversion which has the incidental effect of returning a "rail" service to Ballachulish after very many years. Even if they don't actually stop there for you.

[deltic17]

Firstly I'm glad everyone is pretty much OK and hopefully those with injuries recover fully ASAP.

I'm not trying to speculate as to what happened but if a rock fall did cause this (which seems to be the case as it is now reported on SKY news that a large rock is wedged under the train) the one thing that always comes to mind when you hear of such derailments after an object has been struck is would it have happened if it was a loco and coaches. DMU's are so much lighter than a loco and therefore are more prone to derailment. I always think the same when you see a DVT hurtling south on the ECML being pushed by the Class 91 - I'd rather be heading north with the heavier Class91 leading. Obviously railways change and locomotives at the head of passenger trains are sadly not a common operating practice today either in the UK or elsewhere.

On a slightly different topic it always surprises me that trains can be so short these days (half term week too) - a 2 car Class 156 - I know sadly seats are crammed in today at the expense of comfort but in days gone by this would be a loco +5/6 coaches and yet I believe passenger numbers are increasing generally and have done for quite a few years - or is this the case on the West Highland?

[Hammer]

There's a picture up on the BBC website, which certainly illustrates why the road is closed and will be for a few days. The 156 looks like it's in a rather perilous position. It can't have been easy to evacuate it from there.

 

On a slightly different topic it always surprises me that trains can be so short these days (half term week too) - a 2 car Class 156 - I know sadly seats are crammed in today at the expense of comfort but in days gone by this would be a loco +5/6 coaches and yet I believe passenger numbers are increasing generally and have done for quite a few years - or is this the case on the West Highland?

 

There's only two or three trains to Oban a day and when I've been on them, they haven't been close to full. I suspect it's largely because it's easier for locals to drive to Inverness for big shopping while a lot of Oban's tourists come via coach tours.

[Glorious NSE]

I'm not trying to speculate as to what happened but if a rock fall did cause this (which seems to be the case as it is now reported on SKY news that a large rock is wedged under the train) the one thing that always comes to mind when you hear of such derailments after an object has been struck is would it have happened if it was a loco and coaches.

 

Loco's can be derailed just as easily - all it takes to go into a derailed state is to lift the first wheelset high enough to lift the flange above rail height, that doesn't seem to be hard to do if you get a solid-ish object that goes under the wheelset (think Ufton Nervet, where IIRC it was a solid piece of car, engine block or gearbox?) - even a slide of loose dirt or rock that covers the railheads will derail any train that turns up.

 

The loco's involved in this recent derailment weigh in the region of 200 tons - so substantially heavier than the biggest UK loco's, and there were two of them as well, with a nice massy loaded grain train behind providing plenty of forward motion yet they prove that a rockfall can still derail the train fairly effectively.

 

DMU's are so much lighter than a loco and therefore are more prone to derailment.

 

I don't agree with that assesment - you could also argue that in different circumstances they would be less prone to derailment as their forces on the track are much lower...

[Ragtag]

It can't have been easy to evacuate it from there.

 

According to a BBC radio interview with one of the passengers, they managed to climb up through the carriage and into the other one which was (at the time at least?) still on the rails.

[PaulRhB]

Falls of Cruachan is not an easy place to access the railway. That is the section with trip-wired semaphores which should protect the line against a rock fall.

Nice to hear it was only minor injuries and there's the possibility the rock fall happened while the unit was actually in section so the trips wouldn't have been activated in time to give any warning. Looks like the unit protected the passengers well enough in this case so they've got the balancing act of risk about right for this.

[deltic17]

Sorry - but for me a heavier train/locomotive has more chance of staying on the track if it hits something - the bigger things are - the more stable they are. Mind you if it had been a class 37 and it had derailed then there is a much greater chance it would have ended up going right down the bankside (because of the extra weight/momentum) and ended up on the road/loch with disasterous consequences. I'm sure on this occasion that the lighter DMU has fortunately been supported somewhat by the trees on the bankside. I agree that the bigger the object the train hits (eg car) the more likely that a derailment will occur.

[jamie92208]

Having just watched the 1 0 clock BBC news it appears that only the centre bogies of the unit are still anywhere near the track with the front of the front carriage and the rear of the rear coach down the hillside. They appear to be being held by trees. It would appear that they have all ahd a very lucky escape as the loch is deep and if the unit had gone down it would have sunk completely. Neither coach appears to be too badly fire damaged so I can olny assume that the fuel tanks were split open by the grounding and the fuel escaped quickly with just part of it flashing off as the train ground over the rocks. However this is all very much speculation at this stage.

 

As regards the wreck shown in the US, they must have been very unlucky as there are only 1 or 2 trains per day in each direction. Normally they should ahve been able to stop traffic quite quickly.

 

Jamie

[Gwiwer]

the loch is deep and if the unit had gone down it would have sunk completely.

 

The loch is by definition shallow at its shoreline with the road. It would deepen a short distance out. But even if the entire unit had rolled off the track and down to the road it would not have continued into the water. Inertia carries the train forwards rather than sideways and this is what tends to keep almost any train derailed whilst in service in a reasonably straight line with the track.

 

Trees may have prevented a rollover but trees alone will probably not prevent 75 tonnes of dmu from tipping sideways. It must be resting on something more solid as well.

[PaulRhB]

Loco or unit only matters with the precise set of circumstances at a particular incident. There are times when the lighter unit is better off and vice versa eg if you hit something massive you don't really want a power car or loco at the back but having one at the front can act as an impact absorber, similarly if you hit something flammable then having the loco at the back minimises fire risk, it's all a balancing act of risks.

The Ufton HST was derailed by the car but the catastrophic rollover of the power car and pile up was caused by the derailed wheels hitting the sharp facing point for an engineers siding close to the crossing. The point was subsequently removed as noone had put that together with the crossing as a risk before. ( if you see how short the sighting of that crossing is the drivers reactions were truly amazing and a tribute to the guys at the front real worth )

A train can withstand a highspeed derailment well if it stays straight it's when it's thrown off sideways that the crash structures struggle to cope.

The Pendilino at Lambrigg shows just how good they have got though even in the worst case.

There's an American guy who did masses of research in the 60's into how the human body copes in a crash in cars that shows we can survive massive frontal deceleration compared to sideways.

[Glorious NSE]

Sorry - but for me a heavier train/locomotive has more chance of staying on the track if it hits something - the bigger things are - the more stable they are.

 

Here's another one from across the pond, some classic BN U-boats making a gentle detour guided by nothing more substantial than a bit of snow!

http://krugtales.50megs.com/rrpictale/derails/derails4.htm

 

If you have something relatively solid (be it rocks, dirt, ice, metal or whatever) across a rail or between the rails then the wheel that comes along will be lifted up over that - you've only got to lift the axle past, what, an inch or two of flange before you have the potential to derail?

 

Whether that wheel is attached to 200t of loco or 25t of MU, that wheelset has the same potential to derail if it hits an obstacle that goes underneath it.

[beast66606]

There are devices called derailers, fairly lightweight things which will derail any weight of train ..

 

Of course the heavier the train the - potentially - slower the speed on an uphill climb (was this up hill ?) - and therefore potentially the lower the momentum. Of course the potential energy is higher.

 

Inertia carries the train forwards rather than sideways and this is what tends to keep almost any train derailed whilst in service in a reasonably straight line with the track.

 

 

Momentum is in the line of travel, if the unit was deflected off the straight and narrow the momentum carries it forward in the new direction although at a reduced rate.

 

Inertia is overcoming resistance to start not resistance to stop

[Craig Watson]

I was up there all night, took up the Network Rail incident van then worked as the assistant to the rail incident officer until 08:00 this morning.

 

Craig

 

 

[Craig Watson]

Having just watched the 1 0 clock BBC news it appears that only the centre bogies of the unit are still anywhere near the track with the front of the front carriage and the rear of the rear coach down the hillside. They appear to be being held by trees. It would appear that they have all ahd a very lucky escape as the loch is deep and if the unit had gone down it would have sunk completely. Neither coach appears to be too badly fire damaged so I can olny assume that the fuel tanks were split open by the grounding and the fuel escaped quickly with just part of it flashing off as the train ground over the rocks. However this is all very much speculation at this stage.

 

As regards the wreck shown in the US, they must have been very unlucky as there are only 1 or 2 trains per day in each direction. Normally they should ahve been able to stop traffic quite quickly.

 

Jamie

 

The front coach is down the bank, the rear one is still upright and basically in line with the rear bogie still on the track, various pictures on the BBC and Sky websites show this.

 

Craig

[The Stationmaster]

The loch is by definition shallow at its shoreline with the road. It would deepen a short distance out. But even if the entire unit had rolled off the track and down to the road it would not have continued into the water. Inertia carries the train forwards rather than sideways and this is what tends to keep almost any train derailed whilst in service in a reasonably straight line with the track.

 

Trees may have prevented a rollover but trees alone will probably not prevent 75 tonnes of dmu from tipping sideways. It must be resting on something more solid as well.

 

In that vicinity the loch is 10 metres deep very close to/at the shoreline and - not surprisingly in view of the geology of a 'U' shaped valley - drops very rapidly to 30 metres deep.

[The Stationmaster]

There are devices called derailers, fairly lightweight things which will derail any weight of train ..

 

Of course the heavier the train the - potentially - slower the speed on an uphill climb (was this up hill ?) - and therefore potentially the lower the momentum. Of course the potential energy is higher.

 

Momentum is in the line of travel, if the unit was deflected off the straight and narrow the momentum carries it forward in the new direction although at a reduced rate.

 

Inertia is overcoming resistance to start not resistance to stop

 

 

The mechanics of derailments are quite interesting and I have seen all sorts over the years. The key factors - once something is derailed (and hasn't rerailed itself - more common than you might think) - are exactly as Beast identifies - slow moving derailed vehicles will stop more quickly once they're off than fast moving vehicles but the available mass can make a considerable difference, even at low speed although this can sometimes come out in the way a vehicle 'digs in'.

 

But in any derailment all sorts of factors can come into play and their effects can vary depending on how they mix. And the surface on which something runs, or is prevented from running, once it's off will also make a difference, as do any obstructions derailed wheels might meet and not demolish. The latter is also an area where speed can be important. For example at Ufton the initial derailment was simply the leading pair of wheels of the power car and even at the impact speed of 100 mph there was a slight chance that the derailment might not have got much worse as the train was running onto closely spaced concrete sleepers (although unlike timber sleepers the concrete ones break). But the nasty bit came when the derailed wheelset ran outside the diverging stock rail of the points into the Down Loop and even with a reasonable turnout speed the curve was not only much sharper than linespeed geometry but then entered a slight reverse curve and, of course, the other leading wheel was pulled into and had to climb the open switch rail and that is probably what started to turn the power car and leading trailer onto their left sides before the rail was sufficiently crippled to no longer have that effect; the rest of the train remained upright.

 

If in that case speed had been lower the derailment mechanism would have been no different although most probably much less catastrophic. But if the vehicle axleloads had been heavier the outcome would have been a bit different because the points would have been more seriously damaged by the initial derailed wheels.

 

Are lighter vehicles easier to derail than heavy ones? In some circumstances probably so but generally it's just as easy to derail a heavy axleload vehicle as a light one - the difference is that they can sometimes be a lot harder to rerail as it is necessary to lift more weight I occasionally rerailed low axle weight vehicles by giving them a sharp tug with a loco, I have only once done that with anything vaguely heavy (a Hyfit full of concrete sleepers) and that was really only possible because it was above and more or less in line with the railhead so it was an easy job once buffers were free to pull out.

 

And decent size trees will hold vehicles on an embankment - provided they're strong, well-rooted trees and the load is spread.

 

And a PS for Beast - at one depot I had, I think, at least half a dozen Drivers who had proved that a Class 47 or 50 is just the job for 'dismantling' wheelstop pattern (non) derailers.

[AMJ]

From a trip on the Oban line in August 1987

 

If you have not been on the line or spotted this.

This is one of the signals to signify if there has been a rock fall.

[JeremyC]

The subject of whether a heavy loco is less likely to derail than a DMU etc was raised in the report of the Polmont Accident in 1984 when an Edinburgh - Glasgow push-pull was derailed after hitting a cow while the DVT was leading.

 

The report can be found on the railways archive site Polmont Accident

 

Jeremy

[Fat Controller]

At least they escaped casualties on the scale of the recent derailment due to similar causes in the Alto Adige. Recovery will be a challenge, I am told, as the adjacent road is built on a causeway over the loch, which will make using a road crane very difficult.

[Bruce Depot]

Perhaps a rail mounted crane will be the best option, providing

the jib does not have to swing out top far....

 

Off topic slightly but how did the cl66 at Carrbridge end up being recovered?

 

cheers

Keith

ex AMI