Other mistake: In the opening scene, as Captain Glenn Ford is watching a Japanese freighter travel right to left through his submarine's periscope, the freighter is actually going backwards. The bow of the ship is on the right, not the left, as it should be.
Other mistake: During training, when the men are running and the two British men come out of the bushes then shoot at the ground, there are 3 rows of bullets going past but only 2 guns being fired.
Other mistake: Outlaws are chased by a mounted posse. One outlaw up on a hill shoots two of the posse members from long distance. Next shot, the two injured posse members are lying on stretchers and the chief deputy orders someone to go back to town and get a wagon. The stretchers were canvas, wooden handled, military style. Where did they come from?
Other mistake: In opening scene in the China mission society building, there is a picture of Eric Liddel hanging on the wall. Eric hadn't been born yet.