Two of us once flew a 172 Barton to Mona and back, with a work colleague as pax in the back who'd never flown GA before. My mate flew it there, I flew it back. He's taller than me so had wound the P1 seat down a bit, something I didn't notice until the climb after t/o, with the nose-up attitude.
I reached under the seat for the handle to raise it, but it didn't seem to work. I turned to my mate in the P2 seat and said "it won't go up".
Our colleague in the back apparently (we didn't notice at the time) nearly went into a panic on hearing this. He though I was referring to the aeroplane!