Beechcraft Musketeer Sport III A23-19 Pilot Operating Handbook page 260

Sectlon X
Safety lnformatlon
~ft
Single Englne (Piston)
who take certain drugs, may be more susceptible to hyp-
oxia. Susceptibility may also vary in the same individual
from day to day or even morning to evening. Use oxygen on
flights above 1 0,000 feet and at any time when symptoms
appear.
Depending upon altitude, a hypoxic individual has a limited
time to make decisions and perform usaful acts, even
though he may remain conscious for a longer period. The
time
ot
useful consciousness is approximately 3-5 minutes
at 25,000 feet of altitude and diminishes markedly as alti-
tude increases.
Should symptoms occur that cannot detinitely be identitied
as either hypoxia or hyperventilation, try three or
tour
deep
breaths
ot
oxygen. The symptoms should improve markedly
it the condition was hypoxia (recovery from hypoxia is rapid).
Pilots who fly to altiludes that require or may require the use
ot
supplemental oxygen should be thoroughly tamiliar with
the operation
ot
the airplane oxygen systems. A preflight
inspection
ot
the system should be
peńormed,
including
proper tit ot the mask. The passengers should be brieted on
the proper use
ot
their oxygen system betore flight.
Pilots who wear beards should be careful to ensure that
their beard is caretully trimmed so that it will not interfere
with proper sealing ot the oxygen masks. lf you wear a
beard or moustache, test the fit
ot
your oxygen mask on the
ground for proper sealing. Studies conducted by the military
and oxygen equipment manufacturers conclude that oxygen
masks do not seal over beards or heavy facial hair.
Federal Aviation Regulations related to the use
ot
supple-
mental oxygen by flight crew and passengers must be
adhered to if flight at higher altiłudes is to be accomplished
safely. Passengers with significant circulatory or lung dis·
ease may need to use supplemental oxygen at lower alti-
tudes than specified by these regulations.
10-42
May, 1994