In 1985 an O-boat on patrol off the Falklands had its periscope damaged. It was decided to fly one out via Ascension Island. For very good reasons the task was contracted to Heavylift but of course without AAR Heavylift could only go as far as Ascension.
It was offloaded for onward flight in a Herc. The only problem was the periscope was 57ft long, longer than the Herc freight bay. A very smart Mover realised the top of the freight bay was over 57ft so they created treaties from spare pallets so that it could be elevated and onward shipped.
I don't know if they managed to fit it out there, nor if they brought the u/s one home.