|
|
Post by GentlemanJim on Apr 30, 2013 9:41:59 GMT
|
|
|
|
Post by railtechnician on Apr 30, 2013 9:49:41 GMT
Quite obviously a SPAD !
The throw offs did exactly what they were designed to do so that might be regarded as proof of signalling! I can think of less expensive ways of testing the signalling in this way !!!!!!!!!!!!!!!!!!
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Apr 30, 2013 10:06:36 GMT
The uploader's comment suggests the crew had been to the 'box and received authority to pass the signal, but didn't check the route was set in their favour before proceeding! Presumably the RAIB will investigate and we'll find out exactly why it happened eventually...
|
|
|
|
Post by Nortube on Apr 30, 2013 11:19:33 GMT
I thought it was a demonstration for the public  |
|
|
|
Post by GentlemanJim on Apr 30, 2013 11:46:04 GMT
It does appear from what's being written on Youtube that the driver is passing the signal with authority from the Signalman however, as any driver will know that when passing a signal at danger, even with authorisation, you check the road ahead, it's a simple as that.
Believe it or not it's very easily done as I've done it. Had another driver in the cab, pulled in to Woodford W/B, opened/closed doors, wound up and....... oh manderines! SPAD at LJ17, fortunately I knew the signalman who covered it up but it just goes to show what a distraction can cause.
|
|
|
|
Post by GentlemanJim on Apr 30, 2013 11:46:12 GMT
It does appear from what's being written on Youtube that the driver is passing the signal with authority from the Signalman however, as any driver will know that when passing a signal at danger, even with authorisation, you check the road ahead, it's a simple as that.
Believe it or not it's very easily done as I've done it. Had another driver in the cab, pulled in to Woodford W/B, opened/closed doors, wound up and....... oh manderines! SPAD at LJ17, fortunately I knew the signalman who covered it up but it just goes to show what a distraction can cause.
|
|
|
|
Post by railtechnician on Apr 30, 2013 19:00:53 GMT
One wonders why the signalman would give authority to pass the signal at danger without checking the points were thrown, locked and secured for the route. More than one head should be facing the guillotine ! I'd be pulling both the driver's and the signalman's licenses pending disciplinary action following a fact finding investigation and recommendations for mitigating a recurrence of the incident.
|
|
|
|
Post by class345 on Apr 30, 2013 21:42:28 GMT
Whilst the equipment worked as designed, I've always wondered why they can't be longer where possible, and have detonators placed on them, so the driver gets some form of warning before the derailment.
|
|
|
|
Post by Nortube on Apr 30, 2013 22:40:09 GMT
Depending on the location, they may be used to protect a crossover ahead, etc.
A good example is 32 points at the south end of the siding at East Finchley. 32 points will protect a train going north from the NB middle platform (2) by derailing the train in the siding if it starts to move without the route being set for the SB middle platform (3).
The location of the points is probably based on several things, but the main criteria would be the minimum distance they can be from the line they are protecting.
Obviously, as seen in the video, a certain amount of overrun has to be allowed from the time the first pair of wheels gets derailed until the train actually stops. This would no doubt vary according to the type of train and how quick it would stop (e.g. a heavy freight train downhill, would probably take a bit longer.
If the point blades were made longer, the extra length would have to be allowed for in the positioning of the points. In the example above, this would probably mean that the points would end up before the shunt signal, not after it, and there wouldn't be enough room.
The other problem is the amount of time that it would take the driver to react and apply the brake once they heard the detonator go off. This would also add to the length of the point blades and in fact, even if there was room, it might not be practical from a mechanical point of view, to even be able to use such long blades.
Another example is at the south end of platform 1 at Finchley Central. These points protect NB trains going into middle platform 2 from a reversing S-N train from Mill Hill overrunning the platform.
|
|
|
|
Post by railtechnician on May 1, 2013 7:58:07 GMT
This appears to be flank protection, considering the circumstances of the derailment I would have to say that mitigation would have to be procedural rather than physical as the train was stationary at the signal 'ON' before advancing. Having said that a visible point indication on the signal post might be considered, in the manner of a route secured sign controlled by the lie of the points and the indication of points locked reverse.
|
|
