Revealing mistake: John Wayne suffers a broken arm and goes for a x-ray wearing a cast. At the bottom of the cast a slit is visible which allows the fake cast to be easily removed.
Revealing mistake: In the opening sequence when Colonel Ryan's plane has crashed and is on fire, you can see a metal pole supporting a burning aircraft shell, not a real plane.
Revealing mistake: In the scene where a tank is being pushed to the side by another, it's clear the tanks are miniatures.
Revealing mistake: In the scene where there is a air battle between a DC-3 transport, a American Corsair fighter and a Japanese Zero fighter we see some shots where model aircraft were used - it can be seen that there are wires holding the three aircraft up.
Revealing mistake: In the scene where the boy is shot in the leg and the carried away by an unionist soldier you can see more union soldiers storm past them. The bayonets of the soldiers are obviously made of rubber as they are dangling while the rifles are moved up and down by the running soldiers.