Douglas, after performing a bombing run over the polar bears of Qikiqtarjuaq (Martin screaming in the background), is informed that he left the cabin address on.
"Oh dear. Now that, I admit, was a bit unprofessional."
Upon finding Carolyn on a date with the dashing Captain Herc, Douglas retrieves a piano from the van he and the others are driving to Ottery St. Mary before launching into a rendition of 'That's Amore'.
Pretty much the entirety of Ottery St. Mary qualifies, but especially anything in regards to otters or yellow cars.
"In the unlikely event of Captain nonrecognition, Captain doffs cap, gestures to lipstick inscription."
"The boy stood on the burning deck whence all but he had fled; his heart was in his mouth, but lo, his cap was on his head!"
Also from Fitton, all of Arthur's spirited but horrible attempts at singing.
Ipswich: Douglas is not overly in awe of his captain. He roleplays situations where he is for every drop of sarcasm he can:
"Hey, Chief. I might be wrong, but I think we're flying into a mountain. This makes me feel ... scared of the mountain! One thing we could do is pull up and fly over the mountain. How does that sound to SPHLOOMM!"
Douglas: [clears throat] Hey, Chief.
Douglas: I might be wrong ... [laughs] Sorry, I really must learn to say that with a straight face. I might be wrong, but I think Arthur's about to lose us all our jobs.
Carolyn: This is not—
Douglas: Hang on, I'm only on step two. This makes me feel ... unemployed. And also a little surprised, given that I've heard quite a lot recently that the number of passengers at which it becomes compulsory to carry a flight attendant is nineteen. And I just wonder how often that situation's going to occur in our aircraft ... with its sixteen seats.
Douglas: And: How does that sound to you?
Martin's various attempts at a (horrendous) French accent during Qikiqtarjuaq, and especially his story involving the egg-beater and the pogo-stick.
Douglas and Herc's "syrup-off" in Rotterdam, as they compete over the recording of MJN's welcome announcement.
Carolyn: No, I don't like it either, Martin, but since we have a pilot who sounds like Stephen Fry's favourite uncle, we might as well use him.
Every third moment of every episode. Possibly more.
Arthur getting a go on the tannoy of the disused Uskerty airport:
Arthur: Can I have your attention, please. This is the airport speaking. Listen to the airport. Flight 2020202 is now ready for boarding at gate... eight. It isn't late. It will not wait. If you want to be on that aeroplane... it's time to get on the aeroplane now. If you have young children, put them on the aeroplane. If you have any hand baggage, put it on the aeroplane. If you have any bombs... they're not allowed on the aeroplane. Please put them... in the bin. Okay, bye! Love... the airport.