Greek character carried by Russian plane over an American state (8)
I believe the answer is:
michigan
'american state' is the definition.
(Michigan is an example)
'greek character carried by russian plane over an' is the wordplay.
'greek character' becomes 'chi' (letter from the Greek alphabet).
'carried by' means one lot of letters goes inside another.
'russian plane' becomes 'MiG' (MiG is a Russian aircraft manufacturer).
'over' says to put letters next to each other.
'chi' put into 'mig' is 'michig'.
'michig'+'an'='MICHIGAN'
(Other definitions for michigan that I've seen before include "Lake by which Chicago stands" , "I'm aching to go out the US state" , "US state and Great Lake" , "American state, capital Lansing" , "US Great Lakes state" .)