The only baddish one I had was when I took my girlfriend up in my new (read ancient Cessna Aerobat) wonderplane. I was well aware that she is a nervous passenger in anything and everything.
Take off was normal, gentle climb out, gentle rate 0.25 turn onto downwind, then POP, the bloody oil filler flap catch let go and the flap started waving around right in front of her. Huge screams from the right hand seat and a death grip on my upper body as she threw herself across the cockpit and embraced me. I didn't think that I'd manage to fly the curved approach into Popham's 26 in this position so rapidly went into assurance mode and settled for a death grip on my right arm instead. The oil filler flap was flapping merrily around but we plopped onto the ground OK. Fair play to her, she let me taxi to the hangar, beg some gaffer tape (the catch was knackered) to tape the flap down and do another circuit with her. She went on to do a few lessons but it never really gelled with her.