A mid-flight change into a morning suit had sounded a great jape in the crewroom but it all turned sour when he dropped his cufflinks
or
They'd been arguing for the whole flight about whether auto-fellatio was actually possible or not. Eventually, losing his patience, the pilot graphically demonstrated that indeed one did not need the lower rib removed to manage it!
or
It was a slight comfort to the Nav that at least he was on oxygen however, his main worry now was maintaining positive G for the rest of the sortie whilst holding the soil bucket.