Inspection by nuns possibly finds guinea pig (4,5)
I believe the answer is:
test pilot
'guinea pig' is the definition.
The definition and answer can be both people as well as being singular nouns.
Perhaps you can see an association between them that I don't see?
'inspection by nuns possibly' is the wordplay.
'inspection' becomes 'test'.
'by' is a charade indicator (letters next to each other).
'nuns possibly' becomes 'pilot' (I can't justify this - if you can you should believe this answer much more).
'test'+'pilot'='TEST PILOT'
'finds' acts as a link.
Can you help me to learn more?
(Other definitions for test pilot that I've seen before include "one occupying 21 [COCKPIT]" , "Alan Shepard once?" , "Airman" , "Highly dangerous job" , "One might check bombers" .)