I think for the purposes of the game as well as the small passenger door in the side from which the characters jumped, perhaps Doctor Hainiu had a hatch cut in the floor in front of the tail and the cargo chute went out that way? I hadn't realised but I provided pictures of two different planes, one is a low wing and one is a top wing (is that the right name?) But I think the general type of plane will do. I do like to slip in images for added atmosphere when I can find them.