My first flying experience was at an air show in a Dakota DC10. Absolutly loved it but was sat over the wing and will never forget watching 3 or 4 loose screws, holding the engine cowling, slowly rattling around ..
Most aircraft have a few loose fasteners - rivets and sometimes panel screws - Obviously gas turbines tend not to vibrate as much as infernal combustion engines so the problem is a bit less.
The Avro Shackleton was affectionately refered to as 30,000 loose rivets flying in close formation
I wasn't being entirly serious with the scary comment, I love flying but I do have an overactive imagination sometimes and do my best not to think about the mechanics at work 
Defintely DON'T fly in helicopters then!!
I had a 'jolly' in the back of a Hawk trainer when Iworked at Brawdy in the 80s - flew up the valleys and it was as much as I could do to stop my Bone-dome hitting the canopy every time we banked into a hard turn - I must have had a neck like a bull by the time we got back.
We flew onto the range at Pembrey and fired SNEB rockets at inflatable tanks from a shallow dive. I remembered the skipper saying to look through the gunsight at the marked targets but I couldnt see a bloody thing on the ground that looked remotely like a tank.
By the time we had got back Iwas feeling a bit crap and held down the 'press-to-test Anti-G' button to inflate the anti G suit - it hurt but it stopped the nausea.
After we landed I felt utterly drained and exhausted; I just wanted to go and sleep.
