Enjoy the silence

bluepork once pointed out to me that at no time in London can you see fewer than three aeroplanes in the sky. (Heathrow Airport is the busiest in the world, with 'planes taking off and landing literally every minute; and that's only one of five London airports.)

Not today.

Enjoy the silence from the air while it lasts, and the lack of vapour trails. (I'd say also the lack of vapour-trail-seeded clouds, but possibly the volcanic ash, when it reaches here, will make up for it...)