What the boys in blue may tell us about the air force (5)

I believe the answer is:

royal

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'the air force' is the definition.
(thesaurus)

I cannot understand how the remainder of the clue works.

(Other definitions for royal that I've seen before include "complete" , "like Alonso" , "Relating to kings/queens" , "Of queens, say" , "Sort of jelly, flush or blue" .)

I've seen this clue in the Evening Standard.

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