Short expletive heard on EastEnders - he caught her with a chopper! (10)
I believe the answer is:
helicopter
'a chopper' is the definition.
('helicopter' can be a synonym of 'chopper')
'short expletive heard on eastenders he caught her' is the wordplay.
I cannot quite understand how this works, but
'he' could be 'eli' and 'eli' is found within the answer.
'caught' could be 'c' (cricket abbreviation) and 'c' is present in the answer.
This explanation may well be incorrect...
'with' is the link.
Can you help me to learn more?
(Other definitions for helicopter that I've seen before include "Triple echo (anag) - form of air transport" , "Flier" , "surveillance equipment" , "surveillance vehicle" , "This can be used to transport" .)