Getting a grip on the issue of slippery rails this autumn

Wednesday, 29 September 2021
Behind the Scenes

Falling leaves, damp autumn weather and heavy train wheels can be a recipe for problems on the region’s railways.

As thousands of leaves fall onto the tracks, they stick to damp rails and passing trains compress them into a thin, slippery layer on the rail which – much like black ice on the roads – can affect braking distance, and reduce grip and acceleration.

This means train drivers must slow down earlier for stations and signals to avoid overshooting them. They must also accelerate more gently to avoid wheel spin, which can damage the trains’ wheels. All this can increase journey time and lead to delays for passengers.

Build-up of leaf mulch can also make it harder for signallers to detect a train’s location, causing delays when subsequent trains are unable to proceed until the train in front moves further up the line.

How are Greater Anglia’s trains equipped to deal with this?

Our new intercity, regional and electric commuter (Class 755, 745 and 720) trains are fitted with the very latest Wheel Slide Protection (WSP) systems which have been thoroughly tested and developed over many years to be optimal and makes our trains resilient to the effects of slippery rails.

Like ABS in cars, WSP helps the trains’ wheels to brake more evenly in slippery conditions and stops them from locking up and sliding, preventing wheel damage and wear.

If train wheels slide on slippery rails they can suffer from flat spots (known as ‘wheel flats’) which, depending on their severity, can be a safety issue; can damage the rail; and can create a bumpy ride for passengers.

Wheel flats must be repaired by taking the train out of service and turning the affected wheel on a wheel lathe to make it perfectly round again.

Modern trains also have dynamic traction control systems, to stop wheels from spinning. When trains are trying to take power, they can spin on the spot if they can’t get the grip they need to move the train.

If train wheels spin in one place, the heat created can cause structural changes to the metal, which in turn reduces their life and can cause burns on the track (almost like the reverse of a wheel locking up and sliding).

Much like you may find a traction control button in a modern sports car, modern trains have something similar built-in to stop wheels from spinning.

All trains are also fitted with automatic sanders which deposit a layer of grit onto the rail, and as the train passes over it, the heavy wheels compress the grit which then cleans off the slippery leaf mulch, helping to improve grip.

What’s new for 2021?

We implement a slight timetable change every year, to help maintain arrival times into London, for days when train drivers are braking and accelerating more slowly.

Therefore, from Sunday 10 October until Friday 17 December, intercity trains leaving Norwich, Diss, Stowmarket, Ipswich, and Manningtree before 7.30am will depart up to five minutes earlier, Monday to Friday only.

To help keep tracks clear of slippery leaf mulch, Network Rail will operate six leaf busting ‘Rail Head Treatment Trains’ (RHTT) this year, which will operate 24/7.

The specialist trains will travel around 80,000 kilometres - the equivalent of travelling around the world twice - from 27 September until 17 December to keep rails clear across Norfolk, Suffolk, Cambridgeshire, East London and Essex.

The trains blast leaves off the track using high pressure water jets, then coat the rail with a gel which provides more grip to the train to prevent delays caused by slippery rails.

We will be doing all we can to keep you moving

Our new trains’ ability to cope with slippery rails has improved significantly, leading to improvements in performance over the autumn period.

Last year, delay minutes due to slippery rails were down by 82% compared to the previous year and there were 95% fewer cancellations.

We understand the frustration and inconvenience felt by our passengers if things go wrong, so we continue to work closely with Network Rail to prepare for the season and put in place preventative measures that will minimise disruption.

These include using additional track-cleaning equipment, clearing overhanging trees and other vegetation from the lineside and targeting known problem areas, to try to keep delays and disruption to a minimum.

You can find out more about how autumn affects the railway at https://www.networkrail.co.uk/running-the-railway/looking-after-the-railway/delays-explained/leaves/