Fighter plane, one blowing up cutter (7)
I believe the answer is:
fretsaw
'cutter' is the definition.
(I've seen this before)
'fighter plane one blowing up' is the wordplay.
'fighter plane' becomes 'f' (abbreviation e.g. F-16 etc.).
'one blowing' becomes 'waster' ('blow' can mean 'waste').
'up' says the letters should be written in reverse (in down clue: letters go upwards).
'waster' back-to-front is 'retsaw'.
'f'+'retsaw'='FRETSAW'
(Other definitions for fretsaw that I've seen before include "Woodworking tool" , "Woodcutter" , "cutter" , "Fine-toothed tool" , "Tool for cutting designs in wood" .)