What's the problem with leaves on the line?
Leaves falling onto the track are dragged under passing trains. They're crushed at a force of over 30 tonnes per square inch into a slippery paste. When it's wet, this slippery coating covers the rail and sets to form a hard Teflon like coating. The slippery rails make it difficult for train wheels to grip on the track.
Why does this cause delays?
Trains rely on friction between the wheels and rails in order to get grip, particularly while accelerating and braking. Because the top of the rails become slippery it can take trains longer to pull away from stations. They also have to apply their brakes earlier when they stop.
What is being done to clear tracks and reduce delays?
Out on the tracks
A lot of work goes on to tackle the perennial problem of leaves on the line. Network Rail ensures there are dozens of specialist teams out on the tracks across the UK, clearing leaves 24/7. They also run special trains along affected lines that spray a special gel on tracks to provide more traction.
Driving techniques and an Autumn Timetable
We train our drivers to give them the skills they need to cope with autumnal train driving conditions and, crucially, we make some small changes to our timetable to allow extra time and distance for more gentle braking and acceleration.