Abandon plane - it returned with boy (8)
I believe the answer is:
jettison
'abandon' is the definition.
(I've seen this before)
'plane it returned with boy' is the wordplay.
'plane' becomes 'jet' (jet plane).
'returned' shows that the letters should be reversed in order.
'with' is a charade indicator (letters next to each other).
'boy' becomes 'son' (male child).
'it' back-to-front is 'ti'.
'jet'+'ti'+'son'='JETTISON'
(Other definitions for jettison that I've seen before include "Eject" , "Throw things overboard to lighten ship" , "Ditch (cargo)" , "Throw overboard or discard unwanted material" , "bin" .)