Trilobyte UFO Free 3D model

This is a UFO built for an indepentent documentary made a few years ago about the 'Battle Of Los Angeles'. Back at the start of WWII the anti-air around Los Angeles spotted a large object flying around and spent quite a bit of time blazing away at it but apparently hitting nothing except things on the ground when the shells came back down. Some say it was itchy trigger fingers, others that it was a large UFO that the shots bounced off. I was told to make something alien and futuristic but a bit blimp-like. No image maps used on this, texture maps not required or provided.