Exploits non-British carriers (4)
I believe the answer is:
uses
'exploits' is the definition.
(use is a kind of exploit)
I don't understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for uses that I've seen before include "Puts into service" , "Consumes; treats" , "Puts to a particular purpose" , "Purposes; consumes" , "Exercises" .)