Camera turns 180 degrees in the y direction then mirror image?

i am designing a 3d game in xna. Once my spaceship moves 180 degrees in the Y driection( not x or z), then i get a mirror image.. i dont know why this happens but this happens wether this is in an environment or wether the camera foll开发者_如何学编程ows the spaceship or not. the whole environment changes view and becomes a mirror image of the previous view. Does anyone know why?

Edit: well What kind of info do you need? there is the camera matrices , and the spaceship matrices although it seems that everything is changing , and the controls of course.

it sounds like you might be gimbal locked ... lots of info online (sorry for the brief answer)
http://www.bing.com/search?setmkt=en-US&q=XNA+gimbal+lock