Fighter plane tilts over before burning (8)
I believe the answer is:
spitfire
'fighter plane' is the definition.
(I've seen this before)
'tilts over before burning' is the wordplay.
'tilts' becomes 'tips' ('tip' can be a synonym of 'tilt').
'over' shows that the letters should be reversed in order.
'before' means one lot of letters go next to another.
'burning' becomes 'fire' (fire is a kind of burning).
'tips' backwards is 'spit'.
'spit'+'fire'='SPITFIRE'
(Other definitions for spitfire that I've seen before include "World War Two fighter aircraft" , "Quick-tempered person" , "British warplane" , "WW2 fighter aircraft" , "RAF WW2 fighter" .)