Silent German Helicopters?
This is probably highly unlikely but a friend of mine told me that he and his wife were sunbathing on a Welsh beach and he happened to lok up and saw a helicopter hovering at a distance above his head.
They had not heard it approach and he said all he heard was the whisper of its rotors going round. As soon as he looked up the helicopter turned and flew away.
He said the helicopter had German markings on it.
Is there a version of a "quiet" helo around and could the crew have just decided to see how long they could hover undetected?