What defines the Somatogravic Illusion?

The Somatogravic Illusion is defined by a misperception of the aircraft's attitude that occurs during rapid acceleration or deceleration. This phenomenon occurs because the mechanisms that sense acceleration in the vestibular system can be confused with gravitational forces. When the aircraft accelerates quickly, the sensation may be interpreted as a feeling of being in a climb, even when the aircraft is level. Similarly, during a rapid deceleration, it can feel as though the aircraft is descending. This misperception can lead to errors in judgment regarding the aircraft's true attitude and altitude, which can be critical for pilots to recognize in order to maintain control and avoid accidents. Understanding this illusion highlights the importance of relying on instrumentation rather than solely on physical sensations when flying.