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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