After Cleveland removes the pencil from his abdomen he drops it on the floor of the holding cell, yet once everyone is on the plane he has it again to stab Peter.
During the "Lead Singer of Asia" cutaway gag, their classic hit song from their 1982 debut album begins playing. This song featured the band's original lead singer/bassist, John Wetton. But the "lead singer" featured in this cutaway is clearly modeled after his replacement in the band, John Payne, who did not perform on the original recording of the song.
Instead of a normal steering yoke found in passenger plane cockpits, this one has levers similar to those of old tanks and tracked construction vehicles.