Here's page 16.
? あんなコ いたかしら？
? Who's that girl?
まずいな 早く探すないと。 くりっーーん
This is bad, if I don't find her. Ku---rin.
Sir, can I get you something to drink?
Here, it's obvious that Kurin is addressing Io as "Mr. Customer". Normally, I'd keep with the "-sama" format in the translation, but it's awkward here. It just seems easier to go with what you'd expect to hear in a real airplane in English - "Sir".
Ah-- I thought so!