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Feature Article: Introduction to Illusions
What ever the illusion, it will take a few moments for you
to get reoriented. If the illusion occurs in trimmed flight the
problem is not as severe as it might be if it occurs during maneuvers
as it usually does. Spatial disorientation caused by loss of horizon,
change in power, banking, or other acceleration forces can lead
the pilot to believe that the aircraft is doing something that
it is not. These forces cause the pilot's vestibular and proprioceptive
system to give the somatogravic illusion.
A pilots first reaction will be to over-control in a direction
exactly the opposite to what should be done. The only safe procedure
during the onset of any illusion is to increase your instrument
scan rate.
The brain is capable of separating out the conflict of information
between the eye and the inner ear when the eyes are looking outside
the cockpit. A conflict between the sensory inputs of the body
can be overwhelmed when the natural horizon disappears. When the
conflict of information comes with the eyes viewing relatively
unfamiliar instruments inside the cockpit, the brain can become
confused and then give improper information. This is the origin
of an illusion. You must trust your instruments in IFR conditions.
(See IFR material)
Last Modified January 19, ©2026 TAGE.COM