Safety on the tube at night
 

How safe is the tube central London to Heathrow in the evening?

Very safe

Piccadilly line I believe, to Heathrow. Heavily travelled. No problems at all.

As far as I'm aware, there's not been any kind of crash since the line was inaugurated 35 years ago. Self-evidently, the safety record of the tube is orders of magnitude greater than any other way of getting to Heathrow.

Why do you think accidents are more likely at night?

As to personal safety, very safe. As to train safety, Piccadilly, though old and small, seems quite safe.

Although other some lines (Central or District) make gawd-awful noises that will make you want to plug your ears.