Simplistic dossier about airman (6)
I believe the answer is:
facile
'simplistic' is the definition.
(I've seen this before)
'dossier about airman' is the wordplay.
'dossier' becomes 'file' (I've seen this before).
'about' indicates putting letters inside.
'airman' becomes 'ac'.
'file' enclosing 'ac' is 'FACILE'.
(Other definitions for facile that I've seen before include "Superficial or too easily achieved" , "Easy or superficial" , "Lacking depth, glibly superficial" , "A piece of cake" , "Oversimplified" .)