Feeling a bit stupid...
Taking off from North Weald in C152 after lunch there was a nasty rhythmic banging sound. I thought either the engine was going to quit (though it was developing power nicely) or a control surface was about to depart.
Half way round the emergency low level circut to land, and having declared a Pan, I realised it was the end of my seatbelt dangling out of the door. I retrieved it, did a go around and disappeared back to base feeling a bit stupid.
I'm sure I'm not the first...
Tim