Faster form of attack (6)
I believe the answer is:
'attack' is the definition.
(to strafe is to attack from the air)
'faster form' is the wordplay.
'form' indicates anagramming the letters (another form of the letters).
'faster' anagrammed gives 'STRAFE'.
'of' acts as a link.
(Other definitions for strafe that I've seen before include "Pepper" , "Fire from the air with machine guns" , "Attack with machine guns or cannon from a low-flying plane" , "Set RAF to attack with gunfire" , "bombing raid" .)