Excellent ship backed by energy and skill (7)
I believe the answer is:
Here is my best explanation:
'skill' is the definition.
'excellent ship backed by energy' is the wordplay.
'excellent' becomes 'fine' ('fine' can be a synonym of 'excellent'**).
'ship' becomes 'ss'.
'backed by' means one lot of letters go next to another.
'energy' becomes 'e' (physics symbol as in E=mci).
'and' is the link.