Tackle encapsulating inspector's courage (9)
I believe the answer is:
hardiness
'courage' is the definition.
(hardy can mean tough or courageous)
'tackle encapsulating inspector's' is the wordplay.
'tackle' becomes 'harness' (I've seen this before).
'encapsulating' means one lot of letters goes inside another (I've seen this in other clues).
'inspector' becomes 'di' (detective inspector).
'harness' placed around 'di' is 'HARDINESS'.
(Other definitions for hardiness that I've seen before include "Fortitude" , "Resilience" , "Courage" .)