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Potential Flight Hazards



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.


So what should a pilot do when all visual

references are lost?


Trust the cockpit instruments.


Execute a 180 degree turnaround and start

looking for outside references.


Above all 

 fly the aircraft.

f. Landing in Low Light Conditions.


landing in a low light condition 

 use extreme

caution. Look for intermediate reference points, in
addition to checkpoints along each leg of the route for
course confirmation and timing. The lower the
ambient light becomes, the more reference points a
pilot should use.

g. Airport Landings.


Look for features around the airport or

approach path that can be used in determining depth
perception. Buildings, towers, vehicles or other
aircraft serve well for this measurement. Use
something that will provide you with a sense of height
above the ground, in addition to orienting you to the


Be cautious of snowdrifts and snow banks 

anything that can distinguish the edge of the runway.
Look for subtle changes in snow texture or shading to
identify ridges or changes in snow depth.

h. Off

Airport Landings.


In the event of an off

airport landing, pilots

have used a number of different visual cues to gain
reference. Use whatever you must to create the
contrast you need. Natural references seem to work
best (trees, rocks, snow ribs, etc.)


Over flight.


Use of markers.


Weighted flags.


Smoke bombs.


Any colored rags.


Dye markers.





Trees or tree branches.


It is difficult to determine the depth of snow

in areas that are level. Dropping items from the
aircraft to use as reference points should be used as a
visual aid only and not as a primary landing reference.
Unless your marker is biodegradable, be sure to
retrieve it after landing. Never put yourself in a
position where no visual references exist.


Abort landing if blowing snow obscures your

reference. Make your decisions early. Don’t assume
you can pick up a lost reference point when you get


Exercise extreme caution when flying from

sunlight into shade. Physical awareness may tell you
that you are flying straight but you may actually be in
a spiral dive with centrifugal force pressing against
you. Having no visual references enhances this
illusion. Just because you have a good visual
reference does not mean that it’s safe to continue.
There may be snow

covered terrain not visible in the

direction that you are traveling. Getting caught in a no
visual reference situation can be fatal.

i. Flying Around a Lake.


When flying along lakeshores, use them as a

reference point. Even if you can see the other side,
realize that your depth perception may be poor. It is
easy to fly into the surface. If you must cross the lake,
check the altimeter frequently and maintain a safe
altitude while you still have a good reference. Don’t
descend below that altitude.


The same rules apply to seemingly flat areas

of snow. If you don’t have good references, avoid
going there.

j. Other Traffic.

Be on the look out for other

traffic in the area. Other aircraft may be using your
same reference point. Chances are greater of
colliding with someone traveling in the same
direction as you, than someone flying in the opposite

k. Ceilings.

Low ceilings have caught many

pilots off guard. Clouds do not always form parallel
to the surface, or at the same altitude. Pilots may try
to compensate for this by flying with a slight bank and
thus creating a descending turn.