What is the term for losing orientation to the horizon in flight?

The term for losing orientation to the horizon in flight is spatial disorientation. This phenomenon occurs when a pilot's perception of their position, altitude, or motion is not in agreement with reality, often due to the limitations of human sensory systems. In aviation, this can happen in conditions where visible references to the horizon are obscured, such as flying in clouds, fog, or at night, leading to potential loss of control.

Spatial disorientation is especially critical for pilots because it can impair their ability to make sound judgments about the aircraft's attitude and can lead to dangerous situations. Having an understanding of this term is vital for pilots to recognize the symptoms and take corrective action if they find themselves in such a scenario.

On the other hand, altitude sickness refers to health issues that can occur when flying at high elevations, G-forces relate to the forces exerted on the body during acceleration, and vertigo is a sensation of spinning or loss of balance, which may not directly relate to the pilot's inability to maintain proper orientation with respect to the horizon. Recognizing spatial disorientation and its implications is crucial for safe flying practices.