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shows or demonstrations for entertainment and
advertisements at special events and theme parks.
Generally, the beams from these events appear as
bright blue−green in color; however, they may be red,
yellow, or white. However, some laser systems
produce light which is invisible to the human eye.
b. Currently, there are no FAA regulations that
specifically address the above−mentioned laser
activities. However, FAA regulations prohibit the
disruption of aviation activity by any person on the
ground or in the air. The FAA and the Food and Drug
Administration (the Federal agency that has the
responsibility to enforce compliance with Federal
requirements for laser systems and laser light show
products) are working together to ensure that
operators of these devices do not pose a hazard to
aircraft operators.
c. Pilots should be aware that illumination from
these laser operations are able to create temporary
vision impairment miles from the actual location. In
addition, these operations can produce permanent eye
damage. Pilots should make themselves aware of
where these activities are being conducted and avoid
these areas if possible.
d. When these activities become known to the
FAA, Notices to Airmen (NOTAMs) are issued to
inform the aviation community of the events. Pilots
should consult NOTAMs or the Special Notices
section of the Airport/Facility Directory for information
regarding these activities.
7−5−12. Flying in Flat Light and White Out
Conditions
a. Flat Light. Flat light is an optical illusion, also
known as “sector or partial white out.” It is not as
severe as “white out” but the condition causes pilots
to lose their depth−of−field and contrast in vision.
Flat light conditions are usually accompanied by
overcast skies inhibiting any visual clues. Such
conditions can occur anywhere in the world,
primarily in snow covered areas but can occur in dust,
sand, mud flats, or on glassy water. Flat light can
completely obscure features of the terrain, creating an
inability to distinguish distances and closure rates.
As a result of this reflected light, it can give pilots the
illusion that they are ascending or descending when
they may actually be flying level. However, with
good judgment and proper training and planning, it is
possible to safely operate an aircraft in flat light
conditions.
b. White Out. As defined in meteorological
terms, white out occurs when a person becomes
engulfed in a uniformly white glow. The glow is a
result of being surrounded by blowing snow, dust,
sand, mud or water. There are no shadows, no horizon
or clouds and all depth−of−field and orientation are
lost. A white out situation is severe in that there are
no visual references. Flying is not recommended in
any white out situation. Flat light conditions can lead
to a white out environment quite rapidly, and both
atmospheric conditions are insidious; they sneak up
on you as your visual references slowly begin to
disappear. White out has been the cause of several
aviation accidents.
c. Self Induced White Out. This effect typically
occurs when a helicopter takes off or lands on a
snow−covered area. The rotor down wash picks up
particles and re−circulates them through the rotor
down wash. The effect can vary in intensity
depending upon the amount of light on the surface.
This can happen on the sunniest, brightest day with
AIM 2/17/05
7−5−10 Potential Flight Hazards
good contrast everywhere. However, when it
happens, there can be a complete loss of visual clues.
If the pilot has not prepared for this immediate loss of
visibility, the results can be disastrous. Good
planning does not prevent one from encountering flat
light or white out conditions.
d. Never take off in a white out situation.
1. Realize that in flat light conditions it may be
possible to depart but not to return to that site. During
takeoff, make sure you have a reference point. Do not
lose sight of it until you have a departure reference
point in view. Be prepared to return to the takeoff
reference if the departure reference does not come
into view.
2. Flat light is common to snow skiers. One way
to compensate for the lack of visual contrast and
depth−of−field loss is by wearing amber tinted lenses
(also known as blue blockers). Special note of
caution: Eyewear is not ideal for every pilot. Take
into consideration personal factors − age, light
sensitivity, and ambient lighting conditions.
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