Attack in fast RAF effort (6)

I believe the answer is:

strafe

'attack' is the definition.
(to strafe is to attack from the air)

'in fast raf effort' is the wordplay.
'in' says the answer is hidden in the clue.
'STRAFE' can be found hidden inside 'fast raf effort'.

(Other definitions for strafe that I've seen before include "Blast, shell" , "Make 'Raking Fire'" , "Attack with machine-guns from the air" , "Fire from the air with machine guns" , "Bombard" .)

I've seen this clue in The Sun.

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