The Wallace miner. [volume] (Wallace, Idaho) 1907-current, 1918-09-12

walton of 10000 feet for any length
of time has been found to be strain
on even the most physically perfect
II has also been discovered that many
of the most seasoned filters can not
undergo the sudden quick changes In
altitude, occasioned by diving ana
climbing, without physical deterlora-
ton. 1t was recognized as too great
a risk to subject these men 10 actuai
flviny tests. So the medical labora-
tory at Hazelhurst field undertook to
devise some way of getting the same
results by means of a ground test.
Specialists on Guard.
In the early tests the pilot was
placed in a steel alright cylinder from
which the air was gradually exhaust
ed and then replaced to simulate
flight into the rarefied air of high al
titudes and back to earth. but today
the pilot sits comfortably in the same
rooms with his examiners. His nose
is clamped so that he can not breathe
II.
the breathing apparatus, which is con-
nected by tubes with tank of meas
ured air and With instruments that re-
| cord every breath he takes The air
| Is analysed at various stages of the
run. AS fast as he exhales the air is
taken into reservoir, where 1t Is
cleared of carbon dioxide and then re-
turned to the tank. Gradually he
uses up the oxygen, and thus air con-
ditions of high attitudes are duplicat-
ed. The higher one goes up the rarer
the air becomes; just so with the man
under test; after a certain time he has
consumed an amount of oxygen which
leaves the remaining supply equal to
the oxygen available at a certain al
titude. Time takes the place of height
in the test. "All the way up" so to
speak, several specialists watch him;
one his heart, pulse, and blood press
ure, one his eyes, and the others his
responses to signals and observations
Records of his pulse and blood press
ure are made every other minute. The
eyes are tested every three minutes.
The man under test is kept fairly
plane. Before him on a table is a
bank of small electric lights, one OF
another of which flashes every five
seconds. These he must eXtinguisl
1,1 oh. bo
fore they go out. He has but a few
seconds. Below the lamps is cor
responding set Of buttons, which Wher
touched with a pointer held in thu
right hand. extinguish the respective
lights. Two observers watch him con
stantly and check his errors or delay
ed actions.
Another instrument before him is al
ammeter which acts similarly to ;
speed dial on a plane, and according
ly in the test must be kept at con
slant point One of the examiners
out of view of the pilot, changes thu
pointer from time to time, and it is VI
to the pilot to rectify his dial by slid
ing his right hand along an instru
ment arranged to compensate for tn
change. These two duties keep hi
right hand pretty busy; his left arm
is not used as it has the blood press
ure apparatus attached He is ais,
keeping a small electric fan motor a
a constant speed, the variations il
speed being indicated by changes il
the hum of the motor; the correction
are effected by foot treadle simila
to an accelerator on an automobile
His every movement is noted and re
corded by the observers, who see i
his heart, lungs and eyes accommodate
themselves to the altitude.
Classified According to Record.
AS time goes on (and the test last!
for about 80 minutes) the pilot be
comes bit groggy or sleepy from
lack of oxygen, just as he would at tn,
corresponding altitude, and this con.
dition becomes manifest in changes il
the action of his heart, eyes, ears ant
brain. Along toward the end of hi
run he may let the motor slow down
forget the indicator entirely or mis-.
hitting the light buttons. But he i.
Immediately released when his hear
shows strain or his pulse or respira
ton gets too far from normal
A few minutes after his release from
the apparatus all signs of his recen
fatigue pass away and he becomes
normal again. But very important
record has been established, his future
safety practically assured and he him
self feels that it would be absurd, In
view of the facts shown by the tests
for him to try to fly out of his level
Where argument and theory did not
convince some headstrong pilots be.
fore, they readily accepted the newt
able when Shown today. .-'r.
There are now three classes of pil
OTIS; those few who can endure an al
titude bf over % non faa+ ,,;tbo,,4 -.