Fugitive advanced into part of airport (7)
I believe the answer is:
runaway
'fugitive' is the definition.
(I know that fugitive can be written as runaway)
'advanced into part of airport' is the wordplay.
'advanced' becomes 'a' (abbreviation).
'into' indicates putting letters inside.
'part of airport' becomes 'runway'.
'a' placed within 'runway' is 'RUNAWAY'.
(Other definitions for runaway that I've seen before include "desert" , "refugee?" , "Absconder" , "One who flies" , "Del Shannon hit" .)