watching this video:
and this one:
one of my previous suspicions becomes reality ...
do the DC-8's lack the wingtip strobes?
and:
The anti collision light system (either strobe lights or rotating beacon)...
source:
Navigation light - Wikipedia, the free encyclopedia
so strobes are NOT mandatory as far is I understand this
further more, the image below does not show anything concerned to strobes, only anti-collision lights. In the before take-off part they speak about exterior lights but this is referred to the landing lights and wing lights ...
so the DC-8 has no wingtip strobes ...