Many times in Europe I was minding my own business in some Army helicopter going somewhere on IFR (I follow roads). At one time or another, every fast mover in the NATO inventory would pay a visit. They had advanced radar and IFF, so they knew that we were a military aircraft. We had eyeballs.
They would come screaming in on the deck and come right across our nose. You could read the pilots name on his helmet. They thought it great fun.
My older brother had similar stories, flying OH-58s over (then) West Germany.
One day he was “buzzed” by a couple of Luftwaffe Phantoms. Scared the kaka out of him! ;)