A couple of years ago I flew as passenger seated behind the pilot in a Chipmunk going to a display as one of the Red Sparrows Team
The pilot was a serving senior ranking RAF officer,ex fighter pilot.
I was amazed at the thoroughness of his lookout.
He never stopped scanning the sky, up and down and from one side to the other all the time we were airborne.
I always try to emulate him when I fly.
Lister