Navy planes in dilapidated state (12)
I believe the answer is:
pennsylvania
'state' is the definition.
(Pennsylvania is an example)
'navy planes in dilapidated' is the wordplay.
'dilapidated' indicates an anagram.
'navy'+'planes'+'in'='navyplanesin'
'navyplanesin' with letters rearranged gives 'PENNSYLVANIA'.
(Other definitions for pennsylvania that I've seen before include "State of NE US" , "State of NE? USA" , "State of northeastern US" .)