It's a toss-up between two stories...
1) Flying Hunk of Junk
My first time flying alone at 10 years old from Orlando to Philadelphia on Eastern Airlines (yes, I'm old).
The plane was half-empty and I was seated behind a person who decided that he just had to recline. I moved across the aisle, but the attendant made me move back to my seat.
A few minutes later, the undercarriage of the seat collapsed and I ended up in the floor.
While helping me up, the attendant told me that the whole plane was a pile of junk, and that everything was breaking down or breaking apart...
Just what a nervous kid wants to hear mid-flight.
2) Linda Blair Flies
Just last year, on US Air from Philadelphia to Atlanta. The plane was experiencing turbulence and the lady next to me vomited all over me... I mean it got on my face, my shirt, my pants and in one shoe. No apology, no eye contact, nothing. Most of what she vomited was alcohol, from the smell of it.
The flight attendant freaked when I got out of my seat and told me to go sit down.
I told her that I was not going to sit in a puddle of someone else's puke, regardless of how much the plane was bouncing, and demanded that someone help me clean up.
To "help," she brought me THREE paper napkins.
My call of complaint about the stewardess was absolutely scathing.