Other mistake: In the scene where Burton and Eastwood are in the radio room, two grenades are thrown, which blow the main radio room door off the hinges and Burton and Eastwood run behind the small door and hide in that room. The German soldiers then run up and one of them throws another grenade supposedly into the radio room. However, the actor in his attempt to throw the grenade into the room instead throws the grenade into the door and it bounces back into the hallway in which he is standing and lands in front of him, yet no one reacts to this and seconds later we see an explosion as if the grenade had actually gone into the room, but it is really on the floor in front of the door and would have certainly blown the German soldiers to bits.
Other mistake: After one of Col. Kirby's soldiers has been killed he takes the dead soldier's M-16 and smashes it against a tree. Instead of a magazine the rifle has a plastic sound box, because the 'rifle' is really a toy made by Mattel.