New-York tribune., 1919-05-04
U.S.Weatl1er Bureau Studies
Atmospheric Conditions
to Show Fliers Best Time
for Making Their ''Hop''
Storms Are Not Feared
Aviators Depend Greatly ON
Reports of Experts; Radio
to Warn Men of Danger

WASHINGTON, May 9.-When Co.
lumbus and his three caravels sailed
westward on the first transatlantic
voyage, the great discoverer found that
by keeping to the southwark he was
favored by winds that bore him away
from the Old World and toward the
| Indies.
Now that Columbuses Of the United
States navy are preparing to cross the
Atlantic in the first journey by air
plane-in three big seaplanes-thcy
find that the winds that waited Colum-
bus still are blowing westward, making
it impracticable in the present stage
OF aircraft development TO follow the
southerly route from America to Eu-
rope, even if tho great distance were
not prohibitve. But they find that
farther north, in the latitude of New
toundland and Ireland, the prevailing
direction OF the wind is from west to
east, and that under good wind condi-
tions they may cut three hours or more
from the time that would be required
to travel from Newfoundl and to Ire
land at airplane speed in still! air. The
same thing applies In an airplane Jour
ney from Newfoundland to Portugal by
way of the Azores.
Wind Holds Result Secret
Wind is the one element of para
mount Importance to a successful trans
atlantic flight, according to Professor
Charles f. Marvin, chef of the Weather
Bureau, United States Department of
Agriculture. The Weather Bureau, by
direction of the Secretary Of Agricul-
ture and at the request Of the Secre-
tary of the Navy, is aiding in every
possible way to make the first over
ocean journey a success. friendly
cooperation also exists with the meteo-
rologlcal services of Canada and Great
Britain and aviators of other nations
preparing to make this fight.
AS part of its work the Weather Bu-
reau is using its daily reports from all
stations in the continental United
States to give indications of the most
favorable day for the long flight to be-
gin; 1t has arranged to receive wire
less and cable reports from observing
stations on the west coast of Europe,
from Spitzbergen and Iceland in the
north to the Azores in the south, and
other reports are to come by wireless
from naval stations, ranging in class
from battleships to submarine chasers,
posted on the bosom Of the Atlantic.
All these reports are TO be compared,
charted and summarized in Washing
ton by the official forecaster, who in
this case will be Major E. H. Bowie,
who was on duty as forecaster for the
France during the war. His forecasts
and detailed advices concerning the
meteorological conditions will be trans
mitted to Willis R. Gregg, a bureau
meteorologist, who has studied extern
slvely the relation of weather condi-
tions to transatlantic airplane flights.
and who has gone to Newfoundland,
where the American planes are to take
the air for overseas after flying from
New York, and he now is receiving
summaries of daily conditions Mr..
tween the Weather Bureau and the
naval avjators.
lie is equipped to tell them not only
when no storm is approaching, but to
indicate the successive directions tow
ard which an airplane should be headed
to keep desired course, and also to
calculate the assistance that will be
furnished by the winds.
Little to Fear from Storms
AS far as storms go, the naval avia-
tors have little to fear When North
America and the Atlantic are clear of
great atmospheric disturbances, it is
almost sure that an airplane could
travel over the whole breadth of the
ocean, from west to east, without en-
countering a storm. The reason for
that Is the eastward drift of the at
mosphere, credited sometimes to the
revolution of the earth, and regarded
as responsible for the invariable ten
dency OF storms in northern latitudes
to travel from west to east
a great storm in this country is like
ly to reappear in Europe within few
daysIa TACT that was put to use dur
ing the war by meteorologis with the
American Expcditionary Force. Thus.
II an alrpane gets off from this CONT
nent IN clear weather and with clear
alter its departure is likely to catch it
On the other hand, an airplane travel
ing from Europe to America by the
northern route would do so under tho
fchance OF running into a storm before
reaching this side of the Atlantic. Prac
tlcally all the cyclonic disturbances
tnat move across the United States
enter the North Atlantic Ocean slightly
to the south Of Newfoundland.
Planes to Fly Low
1t Is probable the epochal flight will
be made at an altitude of from 1000
TO 1000 fect-much less than tho
average maintained on long fights
overland. A reason for this is seen
III the pelef OF metcorologists that O.
lransatlantlc aviator would not need
TO n.y. as high as would transconti-
nehtaI aviator In order to derive the
greatest possible assistance from the
winds. The reason for their belief is
that surface winds at sea are nearly
ttwlce as strong as those on land, and
me increase with altitude over the sea
Is much less than over the land The
latter increase on this continent. as
well as in Europe, is nearly 100 per
cent in about 1000 feet.
hatever the wind direction, saw the
meteorol logists, flying at low levels
above the sea would be less dangerous
than at similar levels above the land
because the air above the sea Is less
turbulent or 'bumpy."
Marine weather maps" said Mr..
Gregg to the Philosophical Society of
Washington, "show that an altitude Of
900 to 1000 metres 1900 to 5000 feet
approximately conditions are favor
able tor an eastward trip approx
mately one.third Of the time, the per
centage being slightly greater along
the northern than along the southornn
route. AT greater attitudes the per
centage of favorable days materially
increases, especially along the northern |
route For the westward trip the per-
centage of favorable days Is 80 small as
to make transatlantic flight in this di-
rectlon impracticable until the cruising
radius OF aircraft is increased to such |
an extent that they are relatively inde- |
pendent CT wind conditions.
All things considered, conditions for
an eastward flight are most favorable |
along the northern course; for a west |
watu nlght they are most favorable