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Human Performance

                Peripheral vision works together with our motor sensory apparatus, which is

                located on each side of the head in the inner ear.


                Peripheral vision works simultaneously with central vision. For example, you

                can walk around and read a newspaper at the same time.




                Peripheral vision is the VFR pilot's primary orientation vision.

                However, vision "overrides" the impressions from the sensory apparatus.


                An example: Let's assume that you are flying in clouds. Let's say that you bank

                30 degrees. What you sense is that the wings are horizontal. So, using your

                body's sense of position and the sensory apparatus in the inner ear, you have a

                wrong perception of the plane's position in the air.

                If you then come out of the clouds, vision will have a "curative" effect on spatial

                disorientation, and you will immediately straighten the plane.




                2.5.1.3     Rods and cones


                There are two types of light-

                sensitive cells in the retina:

                  -  Cones

                  -  Rods




                Cones

                Cones  are  concentrated  in  the  central  area  opposite  the  lens,  in  the  fovea

                (yellow spot).

                They are sensitive to colors, fine details, and distant objects.


                Cones  require  bright  light  and  function  best  during  the  daytime.

                They are the cells used in central vision.




                Rods

                Rods  are  concentrated  in  a  band  surrounding  the  central  vision  field.


           Flight Theory PPL(A)(UL)/LAPL             Henning Andersen, Midtjysk Flyveskole© 2025           154
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