A small fleet I’ll float at sea (8)
I believe the answer is:
flotilla
'a small fleet' is the definition.
(I've seen this before)
'i'll float at sea' is the wordplay.
'at sea' indicates anagramming the letters.
'ill'+'float'='illfloat'
'illfloat' anagrammed gives 'FLOTILLA'.
(Other definitions for flotilla that I've seen before include "Group of small craft" , "Group of boats or small warships" , "set of vessels" , "number of boats" , "Fleet of small ships" .)