Russian aircraft drops explosives initially in attack (8)
I believe the answer is:
migraine
'attack' is the definition.
(I've seen this before)
'russian aircraft drops explosives initially' is the wordplay.
'russian aircraft' becomes 'mig' (I've seen this before).
'drops' becomes 'rain' (I've seen this in other clues).
'initially' indicates taking the first letters.
The initial letter of 'explosives' is 'e'.
'mig'+'rain'+'e'='MIGRAINE'
'in' is the link.
(Other definitions for migraine that I've seen before include "Disabling headache" , "causing suffering?" , "Intense headache" , "Thumping headache" , "Recurrent throbbing headache" .)