That would be the flypast at Buckingham Palace to end the Diamond Jubilee. The Red Arrows finished it up and came from the east and after the palace were seen (by me) heading SW perhaps to another flypast/display.
Hi, can you recommend any ways of finding out about such flights? I often wondered if information is published in advance.
Unless you're military or ATC the chances are slim. The Chinooks are very regular London area transit aircraft flying in both directions along the Thames heli-corridor, you'll hear them more than see them! The others....well just look up and you might get lucky to see something.
SHJ