Bail out of plane circling around south of Spain (5)
I believe the answer is:
eject
'bail out' is the definition.
(I've seen this in another clue)
'plane circling around south of spain' is the wordplay.
'plane' becomes 'jet' (jet plane).
'circling' is an insertion indicator (circling can mean going around or containing).
'around' becomes 'c' (abbreviation for 'circa').
'south of' says to put letters next to each other (in a down clue, some letters go under others).
'spain' becomes 'e' (abbreviation for Espana).
'jet' placed around 'c' is 'ject'.
'ject' after 'e' is 'EJECT'.
'of' acts as a link.
(Other definitions for eject that I've seen before include "Send out forcibly" , "Video button" , "Throw or put out" , "DVD player button" , "Throw out violently" .)