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UNIT 6

Weather Hazards

SECTION 1. RESTRICTIONS TO VISIBILITY

1. Visibility

a. There are three types of visibility which affect aviation.

They are: horizontal surface visibility; air-to-air, or flight visibility ; and air-to-ground, or slant
visibility.

(1) Horizontal surface visibility refers to the ability of an observer on the surface to see
other
objects on the surface.

(2) Air-to-air visibility refers to the ability of an observer aloft to see other objects aloft.

(3) Air-to-ground and slant visibility refer to the ability of an observer aloft to see objects
on the surface.

.