Well, in the Dolphin cockpit at least I can understand the difficulty of aiming the angled Lewis'.
However, there are many other accounts of pilots being very effective with pulling down the Foster mounted Lewis on N17's and SE5's and firing into the bellies of 2-seaters and fighters, both surprised and in dogfights. Perhaps the biggest proponent of this tactic being Albert Ball, who has numerous combat reports mentioning just this (below).
Time will tell. Once the full range of the Foster mount is modeled in RoF it will be interesting to see what happens. Just a guess, but I figure there will be just a handful of pilots who will get the nack of it.
I predict having to reload the overwing Lewis will have a PROFOUND effect for Entente pilots. I think there may be quite a few people crying and complaining. I only hope the full rate of fire for the Lewis will be similarly modelled --that thing spat bullets like crazy with no synchronization...
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