Which of the following is one of the three major somatogyral illusions?

The leans is recognized as one of the three major somatogyral illusions, which are errors in the perception of orientation and motion caused by the vestibular system. This specific illusion occurs when a pilot experiences an incorrect sensation of being tilted while in a banked turn, primarily because of the way the inner ear processes changes in motion.

In this case, the individual may feel as though they are upright when they are actually in a banked turn. This misperception arises due to the body's reliance on both visual and vestibular information to maintain orientation, and when that information is discordant, it leads to the leans. Understanding this concept is crucial for pilots, as the sensation can lead to unintentional alterations in flight path or aircraft control if not properly recognized and managed.

The other options represent different phenomena, but they do not align with the categorization of the major somatogyral illusions. The spinning-top illusion, for example, refers to a type of visual or motion illusion that does not fall under the specific types recognized in somatogyral categories. The oculogravic illusion pertains to the misjudgment of vertical position that occurs due to changes in gravitational force on the eyes but is not one