During which phase of flight are pilots most likely to experience somatogravic illusion?

The somatogravic illusion is most likely experienced during rapid acceleration on takeoff because this phenomenon occurs when the inner ear, which helps with balance and spatial orientation, misinterprets the forces acting on the body. During rapid acceleration, pilots may feel a sensation of being in a nose-up attitude due to the strong vertical forces. This can create a false perception of their aircraft's orientation, leading to an illusion of climbing when in fact the aircraft is still in straight and level flight or even climbing slightly.

As the aircraft accelerates, the body experiences an increase in inertial forces, which can lead to confusion about the actual pitch attitude of the aircraft. This effect is particularly pronounced during the critical phases of flight such as takeoff, where changes in speed and vertical motion are rapid and significant.

In contrast, other phases of flight such as routine level flight, emergency descent, or rapid deceleration on landing do not typically present the same intensity of accelerative forces that contribute to the somatogravic illusion. While sensations can occur during these phases, they are not as pronounced or likely to induce this particular illusion compared to the conditions experienced during takeoff.