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Introduction to Glider Flying > Introduction to Glider Flying > Medical Factors Associated with Glider Flying > Middle Ear and Sinus Problems
Since gliders are not pressurized, pressure
changes affect glider pilots flying to high altitudes. Inner
ear pain and a temporary reduction in your ability to hear is
caused by the ascents and descents of the glider. The physiological
explana-ion for this discomfort is a difference between the
pressure of the air outside your body and that of the air inside
your middle ear. The middle ear cav-ity is a small cavity located
in the bone of the skull. While the external ear canal is always
at the same pressure as the outside air, the pressure in the
middle ear often changes more slowly. Even a slight difference
between external pressure and middle ear pressure can cause
discomfort.
During a climb, as the glider ascends, middle
ear air pressure may exceed the pressure of the air in the external
ear canal, causing the eardrum to bulge outward. You become
aware of this pres-sure change when you experience alternate
sen-sations of “fullness” and “clearing.”
During descent, the reverse happens. While the pressure of the
air in the external ear canal increases, the middle ear cavity,
which equalized with the lower pressure at altitude, is at lower
pressure than the external ear canal. This results in the higher
out-side pressure, causing the eardrum to bulge inward.
This condition can be more difficult to relieve
due to the fact that air must be introduced into the mid-dle
ear through the eustachian tube to equalize the pressure. The
fact that the inner ear is a par-tial vacuum tends to constrict
the walls of the eustachian tube. To remedy this often painful
con-dition, which causes temporary reduction in hear-ing sensitivity,
pinch your nostrils shut, close your mouth and lips, and blow
slowly and gently in the mouth and nose.
This procedure, which is called the Valsalva
maneuver, forces air up the eustachian tube into the middle
ear. If you have a cold, an ear infection, or sore throat, you
may not be able to equalize the pressure in your ears. A flight
in this condition can be extremely painful, as well as damaging
to your eardrums. If you are experiencing minor conges-tion,
nose drops or nasal sprays may reduce the chance of a painful
ear blockage. Before you use any medication, check with an aviation
medical examiner to ensure that it will not affect your ability
to fly.
During ascent and descent, air pressure in
the sinuses equalizes with the pressure in the cockpit through
small openings that connect the sinuses to the nasal passages.
Either an upper respira-tory infection, such as a cold or sinusitis,
or a nasal allergic condition can produce enough con-gestion
around an opening to slow equalization and, as the difference
in pressure between the sinus and the cockpit mounts, eventually
plug the opening. This “sinus block” occurs most
fre-quently during descent. Slow descent rates can reduce the
associated pain. A sinus block can occur in the frontal sinuses,
located above each eyebrow, or in the maxillary sinuses, located
in each upper cheek. It will usually produce excruciating
pain over the sinus area. A maxillary sinus block can also make
the upper teeth ache. Bloody mucus may discharge from the nasal
passages.
You can prevent a sinus block by not flying
with an upper respiratory infection or nasal allergic condition.
Adequate protection is usually not pro-vided by decongestant
sprays or drops to reduce congestion around the sinus openings.
Oral decongestants have side effects that can impair pilot performance.
If a sinus block does not clear shortly after landing, a physician
should be con-sulted.
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