Warship bringing doom loaded with gear (7)
I believe the answer is:
frigate
'warship' is the definition.
(frigate is a kind of warship)
'doom loaded with gear' is the wordplay.
'doom' becomes 'fate' ('fate' can be a synonym of 'doom').
'loaded with' means one lot of letters goes inside another.
'gear' becomes 'rig' (rig is a kind of gear).
'fate' going around 'rig' is 'FRIGATE'.
'bringing' acts as a link.
(Other definitions for frigate that I've seen before include "Ship" , "Naval escort vessel" , "US warship" , "Warship - seabird" , "Type of warship" .)