T
RAINING
M
ANUAL
–
L
ANCAIR
IV/IVP
equipment that will provide adequate volume for the descent to 10,000 feet.
Check that equipment before departure.
As part of its charter to promote aviation safety, the FAA conducts regular
courses in high-altitude physiology (with altitude chamber) at FAA’s Civil
Aeromedical Institute (CAMI) in Oklahoma City.
This course meets the requirements for the physiological portion of FAR 61.31
(g)(1) ground instruction. Flight, or approved simulation training is also required
for section (g)(2).
CAMI’s course is given twice a week. A nearly identical program is conducted at
some military bases. All you need do to qualify is have a current medical, be free
from nasal congestion or ear blockages and be clean shaven at the time of the
chamber ride.
CAMI’s Airman Education Programs obtains a list of training dates
from each base that are available to anyone interested in the training. These
dates can be accessed by calling 405-954-4837.
Remember the basic gas laws: Boyle’s, Henry’s, Charles’s, Dalton’s? It’s a
dangerous misconception that pilots of low-performance, non-pressurized GA
aircraft needn’t worry much about gas problems. They explained that gas
maladies manifest themselves in two forms: trapped gas and evolved gas.
Trapped gas can be an unforgettable lesson in Boyle’s Law at work. Simply
stated, air trapped in body cavities such as the middle ear, sinuses, stomach and
even teeth expands as pressure decreases with altitude. At the least, this can
cause mild bloated feeling. At worst, it can result in debilitating pain.
Evolved gas phenomenon is the tendency of gas dissolved in the blood to come
out of solution at higher altitudes and is usually more threatening than trapped
gas. Most of us are familiar with the bends – the result of nitrogen bubbling out
of the blood of a diver who surfaces quickly without decompression stops. Pilots
are susceptible too. Bends can occur at altitudes as low as 12,000 feet. Lesser
known evolved gas problems include Central Nervous System Disturbances
(CNS), paresthesia and the chokes. CNS is probably the most serious evolved
gas problem with symptoms ranging from lines or spots before the eyes to
sensory disturbances and partial paralysis. Paresthesia is tingling or cold and
warm sensations caused by local nitrogen bubbling. The chokes result when
smaller pulmonary blood vessels are blocked by bubbles, causing a stabbing
pain in the chest that’s often accompanied by intense coughing or the sensation
of suffocation.
A chamber ride will teach us to recognize our own hypoxic symptoms. You may
think that hypoxia is just hypoxia, but there are in fact four varieties: hypoxic
hypoxia, histotoxic hypoxia, hypemic hypoxia and stagnant hypoxia.
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19
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©
Copyright
2007
LOBO
May
not
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copied
without
permission.
