Once found a scaffolding plank, about 2” X 10” x 12’ behind the rear spar of a 747.
At a big ultralight fly-in in Gimli Manitoba I flew to (1500 miles I think it was, Pterodactyl 2 stroke UL, no windshield,no heat, no radio,no nothing) and competed in back in the early '80's (won $1,000.00, then met TWO real friendly French-Canadian ladies, but I digress) the last day at the pilot's briefing, there was an announcement that someone had stole the windsock the night before. An opportunity was given to the guilty party to confess, no one did, so the briefing continued. The competition was held, part of which was, given one quart of fuel, who could stay up the longest, that was fun and really showed the most efficient designs plus pilot skill. After the big blow out that night, where I partied with my new north of the border friends, the following morning I started to pack up my camping gear. The 'Dac had a double surface dacron wing with formed ribs, and zippers for access to the folding compression struts, making it a rigid wing that also folded for car top transportation like a hang glider. We XC 'Dac pilots would stow our gear up inside the wing, clothing, sleeping bag, stuff like that. A common practice was to slip a roll of toilet paper onto one of the comp struts, and when needed, land, unzip the wing by that strut, squat down under the wing and take care of business, and there was your paper, it was real handy. Anyway...as I was packing, I unzipped (there was 4 strut zippers, and a 32' span, so lot's of room up there) one of the wing panels and there was the missing wind sock! My Canuck buddies had put it there, I had flown the competition that last day with it there, and still kicked their butts. They of course were all standing there watching me discover this, and we all had a good laugh. Canadian humor, gotta love it.