R
EVISION
:
-
D
ATE
:
12/29/04
P
AGE
:
16
Copyright
2004 Glasair Aviation, LLC Arlington, Washington All rights reserved
experienced on the ground. This, combined with loss of outside visual
reference, can cause vertigo. False interpretations (illusions) result, and
may confuse the pilot’s perception of the attitude and position of his
airplane.
Under VFR conditions, the visual sense, using the horizon as a
reference, can override the illusions. Under low-visibility conditions
(night, fog, clouds, haze, etc.) the illusions predominate. Only through
awareness of these illusions and proficiency in instrument flight
procedures can an airplane be operated safely in a low visibility
environment.
Flying in fog, dense haze or dust, cloud banks or very low visibility with
strobe lights or rotating beacons turned on can contribute to vertigo.
Strobe lights and beacons should be turned off in these conditions,
particularly at night.
All pilots should check the weather and use good judgment in planning
flights. The VFR pilot should use extra caution in avoiding low-visibility
conditions.
Motion sickness often precedes or accompanies disorientation and may
further jeopardize the flight.
Disorientation in low-visibility conditions is not limited to VFR pilots.
Although IFR pilots are trained to use their instruments as an artificial
visual reference in place of a visual horizon, they may still experience
vertigo. This can happen when the pilot’s physical condition will not
permit him to concentrate on his instruments, when the pilot is not
proficient in flying instrument conditions in the airplane he is flying or