A spray bottle filled with water plus a small amount of soap seems to act
like "flak" to knock them out of the sky even as they fly around fast.

The flak fills the air so that they can't fly without hitting it, much like
the Germans did to the Allied WWII bomber fleets trying to save humanity.

The Germans killed a lot of good men using flak simply because the weakness
of the airplane, just as soapy water (supposedly) kills the attacking bugs.
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