Master plan's beginning with a radio-controlled aircraft (7)
I believe the answer is:
padrone
'master' is the definition.
(thesaurus)
'plan's beginning with a radio-controlled aircraft' is the wordplay.
'beginning' indicates taking the first letters.
'with' is a charade indicator (letters next to each other).
'radio-controlled aircraft' becomes 'drone' ('drone' can be a synonym of 'radio-controlled aircraft').
The initial letter of 'plans' is 'p'.
'p'+'a'+'drone'='PADRONE'
(Other definitions for padrone that I've seen before include "who keeps a restaurant?" , "Mafia boss" , "Italian innkeeper" .)