Freezing temperatures alone are enough to cancel a flight. But if a plane does take off in wintry conditions it's because the ground crew got it right.
British Airways has a team on deicers training all year round at Heathrow but in the winter they need extra help. Sometimes that means baggage handlers join the team - the training is extensive and starts on a simulator.
The deicing crews are an essential part of the operation. When the weather gets bad they can turn up at 4am and get 50 planes clear of ice before the passengers even arrive.
As the weather gets worse they can up the tempo and get a giant A380 clear of ice and snow in just 20 minutes.
No matter how hard they try some weather is just too bad. But if we get another 'Beast From The East', the deicing crew say they are ready.