Speeding trains on Aberdeenshire crash line.

[pre65]

An investigation has been launched after two trains went at more than double a speed restriction on the line where a derailment left three dead.

The Rail Accident Investigation Branch said two services went through the 40mph restriction at up to 100mph.

And the bit that baffled me,

"The RAIB said neither of the train drivers was aware of the emergency speed restriction at the time they drove their trains over the affected section of track."


https://www.bbc.co.uk/news/uk-scotla...tland-55587231

[Beeyar Wunby]

Originally Posted by pre65

And the bit that baffled me,

"The RAIB said neither of the train drivers was aware of the emergency speed restriction at the time they drove their trains over the affected section of track."

The fact that 2 drivers missed it would suggest that it wasn't signed properly.

Even if they were aware that there was an ESR out there, fog and darkness might prevent you from knowing you had reached it.

You would start braking at the warning board....if it's not there or obscured, you wouldn't brake and would suddenly come across the Commencement Board whilst still at Line Speed.

Nb, this is NOT unheard of nowadays, I've had it myself!

BW

[TRP]

Something similar happened on the GW main line in Wiltshire last summer, apparently due to Network Rail not properly communicating the change of speed restriction to GWR.

https://www.bbc.co.uk/news/uk-englan...shire-54905117

Tony

[Beeyar Wunby]

w.r.t. the Scottish incident...

Originally Posted by The BBC said

The RAIB said neither of the train drivers was aware of the emergency speed restriction at the time they drove their trains over the affected section of track.

This is odd. The whole point of an EMERGENCY speed restriction is that a driver is not expecting to see it. They can be imposed without any warning, and if set up properly are almost impossible to miss. But they can be set up incorrectly by track workers who haven't been instructed properly.

The sequence approaching an ESR consists of ;

1) A yellow Emergency Indicator board with 2 bright flashing white LED lamps. Hard to miss this BUT, if you weren't looking out the window it wouldn't matter because there's an AWS magnet immediately after it. It will activate the AWS horn in the cab...and if you don't respond to that the Emergency Brake will operate, and you'll be stopped.

2) Shortly after that there's a yellow Warning Board showing the speed in black numbers with 2 retroreflective white circles below it. This is also followed by an AWS magnet, which again you must cancel or it will put the Brake on.

So far then, the driver has been presented with 2 warning boards and 2 AWS magnets they've had to cancel - in a place where there aren't normally any.

HOW THE HELL COULD A DRIVER MISS THIS? (That's a rhetorical question, because it happens )

At this point the driver needs to apply the brake and get hold of the train.This does not require a 'Casey Jones spark shower episode'. Modern trains with disc brakes need only apply a reasonable, steady force to bring the speed down smoothly.

3) So after the train has travelled the allotted Service Braking Distance - which would be over a mile in length to bring a train down from 100mph to 20mph (there are charts and tables to tell the people setting up the ESR how long the approach to the start of the Restriction should be from the Warning Indicator) there will be a yellow Commencement Board. This will display the speed of the restriction in black letters on a yellow board - in this case 20.

And at the end of the ESR will be yellow Termination Board. Once the last vehicle of the train is clear of the T the driver can accelerate away.

If you want to see what these look like, I wrote this Wikipedia section some time ago.....BW's Speed Restrictions

As ever, we await further details of this incident with bated breath.

BW

[Beeyar Wunby]

Originally Posted by TRP

Something similar happened on the GW main line in Wiltshire last summer, apparently due to Network Rail not properly communicating the change of speed restriction to GWR.

[url]https://www.bbc.co.uk/news/uk-england-wiltshire-54905117[/url

That's an interesting read Tony, and I've had a similar experience myself on the ECML! Train driving is a very repetetive job, and once your Muscle Memory has been trained to respond to an ESR, it's easy to not look carefully at the speed board for any small changes that have been made.

My opinion, which I share with many other drivers, is that if any change is made to a restriction that's been established, there should be ADDITIONAL advance warning to advise of it.

Such as...
1)With the modern GSMR radio it is possible for 'Berth Triggered' radio messages to be set up. What that actually means is that the signaller can record a voice message whilst sat at his workstation, and set up the system so that the message is sent to every train that triggers a particular track circuit. So a message like "Will all drivers approaching the 20/100mph Emergency Speed Restriction on the Up Fast Line approaching York, located at 136 miles and 18 chains, be advisd that it has now been changed to 20mph applying to ALL trains. Please press your S button to acknowledge". For safety's sake this can be set up to occur several times before the train reaches the ESR. Once this message is set up the signaller can leave it to work automatically, and can get on with his job of regulating all the other headaches on his panel/workstation.

2) The signaller may be able to set the system so that the last signal before the ESR is maintained at a Single Yellow with Approach Control, so that the drivers HAVE to slow down for the ESR. Since all trains now have to obey this restriction, there's no disadvantage in slowing them all down with signals.

Of course, once ERTMS is established in the UK, Big Brother controller will remove the need for Speed Restriction hardware, as drivers will simply receive an in-cab instruction to slow down.

HTH, BW