The human body and more specifically visual cues and the vestibular system allows us to determine when we are upright, sideways or in a turn. However, when visual references are gone the mind will tend to make up a false sense of which way is straight and level by relying mainly on the vestibular system. These false orientations created by an illusion have been deadly for many pilots, especially for those without any instrument training. Yet having an instrument rating is also not the answer as every human can become disoriented and lose control if they do not believe in their instruments. For these reasons spatial disorientation is the cause of many preventable accidents that lead to a loss of control and become classified as controlled flight
