Page 153 - PPL-engelsk 2025

Human Performance

2.5.1.2 Central and peripheral vision

The eye has two visual fields:

- Central vision

- Peripheral vision

Here is a sketch showing the

two fields.

Central Vision

The central visual field is the small area near the eye's fixation point.

We use central vision for reading instruments, looking out, etc.

We can see colors but are night blind because it requires a lot of light. Central

vision provides the brain with information for further processing and is

therefore resource-intensive to use, as inputs must be interpreted.

The central vision, which we could use during the flight to read instruments,

requires a mental interpretation before we let this "overrule" the other -

perhaps - false sensory impressions.

Peripheral Vision

The peripheral vision makes up the rest of the visual field. It surrounds our
central visual field. It is the orientation vision for perception, and it works

together with our sense of balance.

It does not require much attention to use peripheral vision.

We have night vision via peripheral vision. Our night vision develops in 30 to 40

minutes and is sensitive to oxygen deficiency. Night vision will be reduced at

altitudes of 3000–5000 feet.

Flight Theory PPL(A)(UL)/LAPL Henning Andersen, Midtjysk Flyveskole© 2025 153