Undecided fate of a plane taking paratroopers into battle (4,2,3,3)
I believe the answer is:
left in the air
'undecided' is the definition.
'fate of a plane taking paratroopers into battle' is the wordplay.
I cannot really see how this works, but
'a' is found in the answer.
'into' could be 'in' and 'in' is located in the answer.
This explanation may well be incorrect...
(Other definitions for left in the air that I've seen before include "Held in limbo" , "Stranded; remains undecided" , "Held pending" .)