The chronicle=news., 1913-04-15
Dislike
NATURES TRICKS


London. April. 1.-THE appar-
entity calm atmosphere above
nbounds with air pockets. wind ed
dies and treacherous gusts ever
ready TO toss the unwary airman
and his machine To earth.
Al the cost OF many valuable
lives u number OF these death traps
set by nature have been discovered.
but although the experienced air
man knows they are there. he is
never really certain OF emerging IN
Scathcd from such encounters.
One OF the best known and mos;
dreaded mir traps iS the air pocket
or ''remous" as IL Is called in flying
parlance. This is kind of hole In
the air Of irregular shape. which
renders no supp0vt 10 the wings OF
an ner0pinnc. neither can propeller
blades grip" In those portions of
the atmosphere.
These pockets are often TO he
founa over wooded country or In
valleys surrounded by irregular
ranges OF hills. but they ar. main
iy formed by the sun shining on
damp ground. The heat OF the solar
rays draws the moisture from the
ground and dots the atmosphere
around with patches OF the vacuum.
This Is why airmen always fieh, shy
Of flying In briGh, sunlight.
-.irmen are always nervous OF
flying over low. wooded country. al
though n low altitude Is often ncccs-
sary. II landmarks are to he picked
out and the proper flying route taxi
en-. For trees have dangerous
knoc. OF throwing OFF treachorous
air currents whicn may easily spell
disaster To the airman.
A breeze near the ground. as II
strikes .ac tree branches is directed
| straight up through the air. The
| Airman flying low over the trees
| catcnes this upward current under
one OF his wings. which pushes the
| machine over nj u dangerous angle.
| and the inevitable side slip inter
Senes. The one great prcrnuiion
| against mir currents OF this deEcrip.
'ion is high speed. which gives the
acropianc sufficient stability Ia
withstand diverse currents Of this
kind.
For similar reason no aviator. un-
less forced TO do so. VIII ily low
over n congcsted city. Inc uprising
smoke from chimncys. especially tall
| factory shafts. send up powerful
currents OF mir. which are certain 10
| wreck his machine should they
strike II unawarcs.
The skiliful airman can now fly
his machine In high winds OF 20 tn
10 m.ies an hour with amazing ease.
hut the danger OF such flying IL tina;
| once let u strong wind get behind
| the acroplanc. then trouble IL prct-
~ certain to come. II requires air.
| nh nat -
| turn an acroplanc fhcn th. wind IL
blowing hard In Its wake. for MS the
machin. swings around the wind
Icaichcs l, hroadsidc on and robs II
OF til" speed necessary for stability.
| The aviator who Is caught by II
strong wind In this way Is In u sor-
ry plight. Withou, big risk he can
not land with the wind behind him.
ms the speed at which he would hit
the ysrcund would probably cause
the machine 10 stand on its head.
| The only, thing to do In such n
c!rcimstance IL to turn in u circi.
of several miles In circumference by
slowly cdging the machine around
until II can land in the teeth of tn,
gale.
Even the most expert aviator has
an attack OF ''cold feet'-the name
lsiycn to nervousness in flying cir
clcs--when making u sharp right
hand turn in the air A machine.
when turning to the left. travels
with the whirling blodes of the pro-
peller. hut when swinging around in
the opposite direction. the whole
force OF the propeller blades are up
against II. The result Is that the
tail OF the machine drops in alarm
Ing fashion. and. unless the aero
plane IL fast one. 1t Is likely to
slide downwnrds to earth tail first.
On the other hand. II the machine
is fast one. sharp riEht-hand
turn causcs II To bank over at so
steep an angle to the ground that
directly n sudden wind gust comes
along II is hurled sideways through
the air. ont OF all control OF the I'M
fortunate pilot And this Is very
likely happening. indeed. for sud
ten gusts" are one of the most trou-
hlesome tricks OF nature that air.
men have to guard against.
One OF the unwritten laws of the
air is that flyers should not pass
each other nearer than 20 feet or