Having spent an eternity on this, still can't see these:-
    38 Down - "Vile knitwear one drops in chute"   (4,6)   -A-E  -U-P-R
               ("JUMPER" is in there somewhere, I imagine)
    43 Down - "Malicious flying bomb to be destroyed"    (8)  -I-E-I-H
               (VIXENISH? - Is there a flying bomb called a vixen?)
    50 Down - "Lots of deliveries during term for boarders?"  (5)  O-E-S
               (Surely "OVERS", but where do "boarders" come into the 
    reckoning?  I can't find anything to tie in "boarders" with "overs"