Naval unit announced current maritime control (8)
I believe the answer is:
flotilla
'naval unit' is the definition.
(I know that Flotilla is a type of naval unit)
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for flotilla that I've seen before include "set of boats" , "Fleet of small warships" , "collection of vessels" , "number of small ships" , "A lot of craft" .)