Prepares to fire helmsman, from the sound of it (5)
I believe the answer is:
cocks
'prepares to fire' is the definition.
(I've seen this in another clue)
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for cocks that I've seen before include "Roosters" , "Male birds" , "Adult male chickens" , "Raises" , "poultry" .)