Air carrier's current, seemingly good plane's outside (8)
I believe the answer is:
'air carrier's' is the definition.
(windpipes contain air)
'current seemingly good plane's outside' is the wordplay.
'current' becomes 'wind' (wind is a type of current).
'seemingly good' becomes 'pi' (pi can mean overly pious).
'outside' says to hollow out the word (remove centre letters).
'plane' with its centre taken out is 'pe'.
(Other definitions for windpipe that I've seen before include "The literal trachea" , "The trachea, less formally" , "airline" , "Principal passage by which air reaches lungs" , "breathing space" .)