City Mike succeeds in radioing (4)
I believe the answer is:
lima
I believe this clue is a double definition.
'city' is the first definition.
(Lima is an example)
'mike succeeds in radioing' is the second definition.
(Mike follows Lima in the NATO Phonetic Alphabet)
(Other definitions for lima that I've seen before include "Send mail out to S America" , "Edible bean; capital city" , "city (like 22)" , "Kind of bean" , "Peruvian capital" .)