The Dillon herald. [volume] (Dillon, S.C.) 1894-????, 1919-05-08
OBSTACLES TO FLIGHT ACROSS
ATLANTIC.

"H
/ Washington, May Elemental
obstacles which must be overcome by
aviators attempting to cross the At
Ilantic ocean are pointed out today
by Prof. Charles F. Marvin, chief of
weather bureau, in discussion OF
meteorological conditions along the
proposed routes of the journey.
One of the greatest dangers con-
fronting the transatlantic flyers, ac-
cording to Prof. Marvin, is the fact
that compasses are known to lose
Imost of their precision on airpianes.
He POINTS out that it would be quite
possible for an aviator, flying over
the uniform surface Of the oceans, to
turn his machine unconsciously and
fly away from his object.
| Also, il his machine, making ~hy-
lpothetical speed of 80 miles an hour,
EshouId run into head wind Of 90
miles an hour, he might stay indef-
|initely in the same position over the
ocean. On land a flyer can tell wheth-
Ter a wind is aiding or retarding him,
but over the changeless sea, Prof.
Marvin emphasizes, unless there
were ships within his vision. he would
have little or nothing by which to
gauge his progress.
! The weather bureau chief believes
tcompasses would be somewhere near
useless on transatlantic flights. He
Says:
"The oscillation of the plane itself
lis a large deterrent factor, and 9TH
Lers are the attraction of the motor or
machine material for the needle, and
| the impracticability of making cor
rections while making flights at high
speeds.
Under clear skies sextant obser-
yations make possible the correct
determination of positions. but in
cloudy weather the compass is the
only guide, unless the aviator can
fly high enough to get above the
clouds.
"It is believed necessary that trans
atlantic aeroplanes in the present
stage Of development should be in
constant touch with shipAthat could
indicate positions by wireless. De.
velopments in wireless have made II
possible to tell the direction from
which an air message is sent.
Another factor the transatlantic
flyer must reckon with, says the
professor, is the defective Influence
of the carth's rotation upon aeroplane
+, flight. Objects moving freely over
the earth's surface are DETECTED con-
stantly to the right.
The naval ayiators have little to
fear from storms, Chief Marvin de-
clares. When North America and the
Atlantic are clear of great atmos-
phere disturbances, it Is almost sure
that an aeroplane could travel over
the whole breadth of the ocean, from
west to est without encounting a
storm.
'cThe reason for that" he added "is
the eastward drift Of the atmosphere
credited sometimes to the revolution
of the earth and regarded as respon-
Isible for the :invariable tendency of
storms IN northern latitudes to travel
from west to east. A great storm In
this country is likely to appear in
Europe within few days--a fact
that was put to use during the war
lby meteorologists with the American
expeditionary force"
Prof Marvin says it is probable
that the, epochal flight will be made
at an altitude of from 1000 to q
1000 feet-much less than the aver
lage maintained On long overland
flights. He sees a reason for this in
the belief of. meteorologists that a
,transcontinental airman, in order, to
derive the greatest possible assistance
1 from the winds. Surface, winds at sea
are nearly twice as strong as those
on land, and the increase with alti-
tude over the sea is much less than
over the land.