Goofs

At 1:18:54 into the film, the sound and closed captioning indicate "helicopters whizzing," while at the same time, two dirigibles are shown carrying a net.

At 54:00 when airplanes attack the Gappas, for a brief moment during a view from an airplane target one can see where the fake sky backdrop ends and the movie studio beyond it.

While the three Gappas (male, female and baby) all have bird-like wings, when they fly, there is no sign of these wings being used as propulsion, nor is there any other form of propulsion that is seen or even implied.