Charlie's predecessor is excellent (5)
I believe the answer is:
bravo
'charlie's predecessor' is the definition.
(in the NATO phonetic alphabet)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for bravo that I've seen before include "next to alpha" , "B in radio communications" , "Jolly good" , "Theatrical 'well done'" , "Good job!: international radio code word" .)