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Sallyann1234
21st Oct 2016, 12:51
So now we don't have to wait for disruption due to leaves on the line. The leaves have their own schedule! :ugh:

Autumn leaves will delay the return of 33 Gatwick Express services previously axed, a railway company has said.

The services had been cancelled amid staff shortages, and Govia Thameslink Railway (GTR) has now said they will not return until 12 December.

GTR, which owns Southern, said the decision was due to "autumn leaf-fall arrangements".

Autumn leaves blamed for fewer Gatwick Express trains (http://news.sky.com/story/autumn-leaves-blamed-for-fewer-gatwick-express-trains-10626061)

TURIN
21st Oct 2016, 22:03
Methinks they protest too mulch!

Thankyou.

RedhillPhil
21st Oct 2016, 22:09
Non-story. Happens every Autumn all over Europe. Invent a system that prevents it without the obvious of hacking all the broadleaf deciduous trees down and you'll make a fortune.

meadowrun
21st Oct 2016, 22:16
they will not return until 12 December

Damned leaves.
42 days to clear them. Worse than Ebola.
I don't get the staff shortage thing tho'. Aren't there a few unemployed in the UK? Shortage of training staff? You know, people who know how to run railways?
Well, it's only a Major International Airport leading to a Major Capital City.

hiflymk3
21st Oct 2016, 22:17
Modern trains are light compared to them old steam locos which because of their weight had better traction.

meadowrun
21st Oct 2016, 22:24
The gradients in the 29.5 miles between Gatwick and London can be real hell.

Economics101
21st Oct 2016, 23:19
hiflymk3: it's not the weight or axle load of modern trains that's the real problem. It's largely the fact that they use disc brakes. Old-fashioned brakes were cast-iron brake-blocks which acted on the same part of the wheels which came in contact with the rails. This ensured they they were scraped clean of the slippery goo which results from wet and compressed fallen leaves. Disk brake leave the vital parts of the wheels untouched.

Even more dangerous is the fact that disc-braked trains may not stop as desired, but can skid a long distance due to lack of adhesion between gooey wheel and rail.

Loose rivets
21st Oct 2016, 23:22
Haven't they got ABS??!!


Whatever happened to the old sandboxes?


TURIN. Methinks you've misplaced Methinks. :8

Sallyann1234
21st Oct 2016, 23:28
Of course we get train delays and cancellations due to leaves every year. They are expected. But only on the actual days when the leaf falls have been heavy.

This seems the first time that cancellations have been scheduled for every day, even for days when leaves are not going to be a problem. It does seem to be a cover-up for the train company still not being able to run the full intended schedule.

Perhaps on the 12th December they will be able to roll out their new schedule for "winter snow-fall arrangements" ?

BlankBox
22nd Oct 2016, 01:56
...get one of these...

https://s-media-cache-ak0.pinimg.com/564x/18/ea/0c/18ea0ca016b7c6bc9183af3868ed5899.jpg

gruntie
22nd Oct 2016, 09:03
Why doesn't every train clear its own track anyway? A small jet of compressed air in front of the lead wheels would do it. Being removed before they were squashed, leaves wouldn't turn to mulch either.

Blues&twos
22nd Oct 2016, 09:42
Depending on type, trains can have wheelslip protection (wheels spinning under acceleration) and anti-slide (wheels locking under braking). In autumn 2010 a passenger service approaching Stonegate station in Sussex at 65mph encountered "low adhesion conditions" and skidded past its intended stop by just under two and a half miles. The sand supplies had run out, of which the driver was unaware. There's a RAIB report covering the incident and the other factors involved.

https://www.gov.uk/raib-reports/station-overrun-incident-at-stonegate-east-sussex

evansb
22nd Oct 2016, 09:49
Yes! Too cool new tech! Luv it.

As a youth my Dad recanted the following: Amidst the heat of a Prairie summer "...in 1933, the small incline of the track resulted in a CNR (Canadian National Railroad) freight locomotive spinning her drive wheels in vain, slipping BACKWARDS as a result of a huge infestation of CATERPILLARS crossing the rails."

Yup! Those slippery buggers stopped and delayed many a train in the hot summer of a mid-indeterminate 1930's (probably 1933) Canadian depression. The engines (locomotives) were indeed equipped with sand dispensers, however by the dust bowl of 1933, most locomotive traction bins were, ironically, empty of sand..

Sallyann1234
22nd Oct 2016, 10:18
As a youth my Dad recanted the following:

You were there when your Dad was a youth?

ShyTorque
22nd Oct 2016, 10:42
I thought this was about aerobatics....

Loose rivets, ABS isn't much use when you don't need to steer whilst braking...

fedex727
23rd Oct 2016, 10:40
There's not a lot of contact area twixt wheel and rail either...

WilliumMate
23rd Oct 2016, 11:17
Before retirement I was a train driver. I used to drive the water jetting trains that attempt to clear the compacted mulch in known low adhesion areas. One morning on the line between Carlisle and Newcastle the biter was bitten and slid over one and a half miles despite frantically dropping sand and cautious use of the brake. Eventually threw the brake into emergency and sat back and waited. Bit scary thinking back about it.

radeng
23rd Oct 2016, 16:28
It was a problem on Glendoune bank back in the mid 19th century. Nothing new.....

sycamore
24th Oct 2016, 14:22
Just had a roadsweeper up and down here...can`t they fit trains with something similar to the `whirling brushes`,or a couple of `stiff-brooms`,airmans,for the use of`...?

Blues&twos
24th Oct 2016, 20:38
Just had a roadsweeper up and down here...can`t they fit trains with something similar to the `whirling brushes`,or a couple of `stiff-brooms`,airmans,for the use of`...?

Railhead treatment trains (RHTTs) are used. Unless the technology has changed recently, they use high pressure water to jet wash the rails. This will get rid of most stodgy mulch, but won't make the rail immune to being slippery if, for example, there is light rain.

jimtherev
24th Oct 2016, 22:01
On our narrow-gauge line I've experienced the embarrassment of slipping to a halt on a misty Spring or Autumn day - not a leaf in sight. The steel rails get a very light coating of rust overnight, which we find makes a wonderful lubricant when mixed with dew. It's then operate the sanders, and if that doesn't work, getting the guard to trot up the line with a bottle of sand. (Don't tell elfin safety!)

WilliumMate
25th Oct 2016, 10:32
Railhead treatment trains (RHTTs) are used. Unless the technology has changed recently, they use high pressure water to jet wash the rails. This will get rid of most stodgy mulch, but won't make the rail immune to being slippery if, for example, there is light rain.

Very high water pressure. It's just one of the methods used. Trees are seasonally lopped as felling them would undermine cuttings leaving them prone to landslip. A water and sand gloop (sandite) is applied to rails to aid adhesion.

Despite the regular beatings that train companies receive (almost always deserved) leaf fall season is an unavoidable nuisance. Sliding along on a congested commuter line with short signal sections and another trains tail lamps in front of you leads to a seriously squeaky bottom.