RAF set out to fire upon ground target (6)
I believe the answer is:
strafe
'fire upon ground target' is the definition.
I can't tell whether this defines the answer.
'raf set out' is the wordplay.
'out' indicates anagramming the letters (out can mean wrong or inaccurate).
'raf'+'set'='rafset'
'rafset' anagrammed gives 'STRAFE'.
'to' acts as a link.
Can you help me to learn more?
(Other definitions for strafe that I've seen before include "Attack with machine-gun from the air" , "Make 'Raking Fire'" , "Attack with machine-guns from the air" , "Attack from the air with machine guns" , "Spray with gunfire" .)