The shot of the Landing Craft, PA-11, is seen twice during the first beach landing scenes. The troops exit in exactly the same manner, including the soldier who runs to the immediate right of the craft.
Just before the crew begins to seal the hatch to make an air bubble, light can be seen reflecting off the water deep in the hold. For this to happen there would have to be an above water opening in the side of the ship, which would make an air bubble impossible. However, the hold is obviously a stage setting with lights above the water to make it visible.