I forgot to state that it is powered by an air-indepedant system. Not too much different than what some modern non-nuclear sumarines use in real life. All the vehicles in my novel (includng mechs) use air-independant systems because not all planets have oxygen atmoshpheres (many planets have no atmsphere at all).
I see that women are the main characters in your story. Mine as well. Actually there are two main Characters:; a man and a woman-- Both scientists, engaged to each other. BOTH share a nearly equal amount of screen time, and responsibility, in the story.