Independent small spacecraft, one based in Sicily? (8)
I believe the answer is:
islander
'one based in sicily?' is the definition.
(Sicily is an example of an island)
'independent small spacecraft' is the wordplay.
'independent' becomes 'i'.
'small' becomes 's' (abbreviation - e.g. clothes size).
'spacecraft' becomes 'lander' (eg a moon lander).
'i'+'s'+'lander'='ISLANDER'
(Other definitions for islander that I've seen before include "Inhabitant of Fiji, for example" , "Isolated dweller" , "Manxman, maybe," , "Corsican, for example" , "Perhaps Sardinian" .)