......are there any conditions.......

[whole diary]

[ellendune]

The leaves on the line - I would agree would count as moderate weather - and railways must find a way to cope.

However the gales in Scotland and Northern England this week and the previous gales in Southern England at the end of October were extreme and we should expect that our railways will be affected by them.

[Chris from Nailsea]

The leaves on the line - I would agree would count as moderate weather - and railways must find a way to cope.

Playing devil's advocate, then, ellendune: What would you suggest as that simple solution to Network Rail's annually recurring problem? 

[ellendune]

The leaves on the line - I would agree would count as moderate weather - and railways must find a way to cope.

Playing devil's advocate, then, ellendune: What would you suggest as that simple solution to Network Rail's annually recurring problem? 

Oh I quite agree that it is not easy incredibly difficult to solve, but it is not possible to write it off as exceptional weather in the same way as the winds of recent days. The leaves do not affect roads or air travel so people will not understand.

[broadgage]

The leaves on the line - I would agree would count as moderate weather - and railways must find a way to cope.

Playing devil's advocate, then, ellendune: What would you suggest as that simple solution to Network Rail's annually recurring problem? 

1) Cut down trees on railway property, especially those with problematic leaves. Many rail routes now resemble linear forests if compared to pictures taken 20 or 30 years ago. This will also reduce delays due to fallen trees.

2) Consider fitting new trains with tread brakes that when applied scrape leaf residue from the wheels. (the replacement of tread brakes with disc brakes is one of the reasons that new trains are worse than old in leaf fall weather)

3) Install leaf traps at particularly bad locations. These consist of short lengths of chain link fencing installed at an angle to the track. The prevailing wind and the air movement from trains blows leaves against these fences were they become trapped rather than blowing onto the rails.
The leaves can then be collected, or burnt on site, or allowed to decompose naturally.

4) Ask overseas railways how they cope ! Leaves on the line do cause delays overseas, but not it seems on the scale that we suffer.

[Network SouthEast]

1) Cut down trees on railway property, especially those with problematic leaves. Many rail routes now resemble linear forests if compared to pictures taken 20 or 30 years ago. This will also reduce delays due to fallen trees.

How can you do this when many trees aren't on railway land? Network Rail are good at cutting down trees and removing foliage on their own land, but what can they do when the tree is in someone's back garden? What can they do when a tree has a preservation order on it? What if they remove a tree from an area with a venerable embankment and then it leads to landslides?

2) Consider fitting new trains with tread brakes that when applied scrape leaf residue from the wheels. (the replacement of tread brakes with disc brakes is one of the reasons that new trains are worse than old in leaf fall weather)

Fitment of tread brakes would prevent trains running fast. Tread brakes have terrible braking performance at higher speeds, that's why we see brake discs fitted to pretty much anything that moves quickly (i.e. Mk3s, 158s, Turbos etc).

[ellendune]

1) Cut down trees on railway property, especially those with problematic leaves. Many rail routes now resemble linear forests if compared to pictures taken 20 or 30 years ago. This will also reduce delays due to fallen trees.

How can you do this when many trees aren't on railway land? Network Rail are good at cutting down trees and removing foliage on their own land, but what can they do when the tree is in someone's back garden? What can they do when a tree has a preservation order on it? What if they remove a tree from an area with a venerable embankment and then it leads to landslides?

Recent research suggests that the link between trees and embankment stability is not as simple as we had thought. We had assumed that the tree roots would bind the soil together.  However it now seems that in dry summers the presence of trees in clay soil embankments leads to further drying of the clay, which causes cracking. When the soil rehydrates these cracks remain as a weakness in the embankment structure. 

2) Consider fitting new trains with tread brakes that when applied scrape leaf residue from the wheels. (the replacement of tread brakes with disc brakes is one of the reasons that new trains are worse than old in leaf fall weather)

Fitment of tread brakes would prevent trains running fast. Tread brakes have terrible braking performance at higher speeds, that's why we see brake discs fitted to pretty much anything that moves quickly (i.e. Mk3s, 158s, Turbos etc).

Would it be helpful to fit, in addition to the disk brakes, a sort of wheel rim scraper (something that looks like an old fashioned rim brake) which could clear the leaf slime off the wheel rim?

[broadgage]

There are a lot of mature trees on railway property that were but saplings 20 or 30 years ago. Many could be cut down, or drasticly cut back.

Not much can be done about trees on other peoples property, but they could make a start on the railway owned ones. (and possibly offer to remove unwanted trees on private property)

Tread brakes do indeed have inferior stopping capacity as compared to modern disc brakes. It has been suggested that a basic tread brake be added to disc brake wheels, as suggested in the previous post. Since most of the stopping power would come from the disc brakes, the blocks on the tread brakes should be long lasting.

[ChrisB]

NR^» (Network Rail - home page) used to do a lot of trackside vegetation & tre clearance, but with funds short, it's a 'wait until they fall' policy now

[IndustryInsider]

There are a lot of mature trees on railway property that were but saplings 20 or 30 years ago. Many could be cut down, or drasticly cut back.

NR^» (Network Rail - home page) used to do a lot of trackside vegetation & tre clearance, but with funds short, it's a 'wait until they fall' policy now

There are indeed many locations where vegetation could be significantly cut back.  Even a 'main line' like the Cotswold Line has several locations where leaves have been allowed to grow right up to where the train profile is located, and as soon as a shower weighs the leaves down they smack the side of the train as it passes in the summer.  That's also a safety risk for passengers who might lean out of the window of a HST^▸ (High Speed Train) at the wrong time and get a face full of leaves at 90mph - I know they shouldn't, but people still do!

[ChrisB]

Worse still, is that NR^» (Network Rail - home page) have apparently cut back on using sandite....

[Henry]

 I have also heard that now the 'leaf fall season is now over' no further sandite trains.

 If my part of Devon is anything to go by, there's still some way to go yet.
 After last week's series of events at Totnes, I've given up using the train for a few months.

[ChrisB]

Over? - it obviously isn't!

NR^» (Network Rail - home page) need to accept that leaf-fall doesn't just finish when they want it to.....doh!

[stuving]

From the RAIB^▸ (Rail Accident Investigation Branch)

Buffer stop collision at Chester station

At 12:10 hrs on Wednesday 20 November 2013 a passenger train collided with the buffer stop at the end of platform 1 at Chester station and became derailed. The train involved was the 10:10 hrs Virgin Trains service from London Euston to Chester. Two passengers on the train were slightly injured in the collision.

As the train approached Chester station the driver applied the brakes to reduce the speed for the 20 mph speed limit into the platforms. The weather at the time had been dry but a rain shower was just starting and the adhesion between the wheels and rails was reduced. The train^s wheel slide protection system detected that the wheels were sliding on the rails, regulated the application of the brakes, and the train was able to achieve a rate of deceleration sufficient to bring its speed down to within the speed limit as it approached the station.

As the train approached the platform the driver lightly applied the brakes again but the wheels immediately started to slide. Despite the immediate automatic activation of the wheel slide protection system, the train^s deceleration was insufficient to bring it down to a safe speed as it moved along the platform. Consequently, the emergency brakes were applied by train protection and warning system and the driver pressed the emergency stop button very shortly afterwards. The combination of emergency braking and the detection of wheel slide triggered the automatic sanding system on the leading vehicle to drop sand onto the rail head.

The presence of the sand improved adhesion for the wheels that ran over it and the speed was reduced before the train collided with the buffer stop at the end of the platform.

The buffer stop was of an old design with only minimal capacity to absorb energy. The train destroyed it before overriding its remains to mount the platform where it came to rest. The front bogie was lifted off the track as the front of the leading vehicle rode up onto the platform.
 


Image of derailed train at Chester station

Platform 1 was closed to traffic until the following day for recovery of the train and repair of the track and buffer stop.

The RAIB^s investigation will seek to identify the sequence of events. It will include consideration of the braking system on this train, in particular the wheel slide protection system and the sanding equipment. It will also consider adhesion conditions in the area at the time (using information from other trains that experienced low adhesion conditions that day), the condition of the rails on the approach to the platform and the efficacy of any actions taken to treat the rail head.

The RAIB will also take into consideration the findings from other similar events that the RAIB has investigated; most notably the investigation into a series of low adhesion events in the autumn of 2005 (RAIB report 25/2006, parts 1 to 3).

The RAIB^s investigation is independent of any investigation by the Office of Rail Regulation.

The RAIB will publish its findings, including any recommendations to improve safety, at the conclusion of its investigation. This report will be available on the RAIB website.

You can subscribe to automated emails notifying you when the RAIB publishes its report and bulletins.

I though this was relevant here - it is braking rather than traction effects of low adhesion, but closely related.

If you want to see how much work and head-scratching has gone into the topic, follow the link to their previous report 25/2006 part 3. This observes (inter alia) that the many new trains introduced in 2004-2005 recorded more "failure to brake" incidents than the older ones, but does not really find out why. They seem to be suggesting that this new report will review what has happened since 2006, though that review may be quite limited if it is just what is relevant to this accident.

If you still want more information there are several RSSB^▸ (Rail Safety and Standards Board) reports - search through the catalogue for "adhesion working group" and you should be kept busy for hours.

[BerkshireBugsy]

I've just picked up on this thread and found it very interesting reading.

This week I am working in the Edmonton area of north London again. The last times I've had to do this gig I've travelled by train from Thatcham . The journey time could vary as much as an hour even if there were no major delays because the end point of the journey is at a station served by very few services (angel road) to be honest when I did this a few weeks ago the signalling issues were starting to wear on me a bit.

So this morning I was driving to the station and on the spur of the moment I decided to drive to site. At 515 this morning I had a good run through and because I arrived on site early I left early and was home by 535 - about 2.5 hours earlier than if I had done the journey by train.

Of course , as others have posted, the roads are subject to delays but  my feeling is if that happens I can choose to take an alternative route whereas if I was on a mass transit system (such as a train,tube dlr etc) that option wouldn't be available to me

If I was working in Central London then this is not an option I would consider although on occasions I have driven to hatton cross and take the tube in.

Ironically I feel more alert having driven although I can't explain why. I (personally) find train travel more tiring in the darker months.

I am conscious that taking today as an example my driving could be considered as environmentally selfish but it gave me back between 3-4 hours of my life. Like others though I can't stand sitting in jams- such a waste of time.

[stebbo]

Older locomotives and carriages - note not modern multiple units - had tread brakes as rightly pointed out in an earlier post so the driving wheels were cleaned off. Also, steam engines and older diesels with steam boilers had the ability to spray steam onto the tracks under the driving wheels.

Tube trains carry some de-icing equipment to clean the live and return rails. Shouldn't modern BR^▸ (British Rail(ways)) stock have something similar? (OK I hear the argument that the problem doesn't occur regularly - I'd buy that for snow clearance but not leaf fall/frost).

And, of course, better tree surgery would help given we no longer have steam locomotives to help burn off the canopy. It was not so long ago that the lineside vegetation used to bang against the side of trains along the Cotswold Line.