RE: I got real lucky
For some reason I am finding it hard to believe that checking servo arm connections should be on everyone's pre-flight checklist. I could see this being something that could be easily overlooked no matter how much experience you have. I don't know about you guys but I don't inspect each servo before every flight other than going by sound/malfunction. It is interesting though that the screw managed to work itself out from the time you did the control surface check to getting it in the air while still managing to keep itself in the servo arm after landing. Is it possible you just didn't notice that it wasn't working correctly when you did your surface control check?