Evening star., 1934-10-30
BALL0ON|ST LIMIT
PUT AT 20 MILES
Scientist Calculates Types
of Craft and BalIasts in
Future Accents.
BY THOMAS r. HENRY.

BY THOMAS r. HENRY.
Man will never get more than 20
miles into the sky in balloon.
Theoretical calculations set limit
in the stratosphere of approximately
100000 feet for future ascents in
lighter -than-air contrivances pro-
vided there are no radical develop
ments in design or conditions in the
upper air of which science has no
information.
The theoretical possibilities have
been computed by DR.. L. B. Tucker
man of the National Bureau Of Stand
ards in connection with his work Of
ascertaining the causes of the series
of mishaps to the National Geographic
Society's stratosphere balloon, Ex-
plorer. Some of the successful aScents
of 10 miles or more into the stratoS-
phere in the past four years have
given rise to much speculation as to
the extreme possibilities.
72,178 Feet Is Record.
The present unofficial record of 72,-
l78 feet above the surface of the
CdL III Wdo Hlduc Wy IIlC INQooldA pdl-
loonists Vasenko and Usiskin last
January, and the men perished in
their descent, due to neglect Of one
Of the factors which seem to set an
almost uncrossable boundary to voy-
ages outward from the planet.
To ascend higher and higher, it is
pointed out, larger and larger balloons
are necessary, and to get down from
greater and greater heights safely,
more and more ballast must be carried.
The amounts go up slowly at first.
Thus they are computed by Dr. Tuck
erman for distances which actually
have been reached:
Fifty-four thousand feet, 2,100
pounds for balloon and equipment and
l,040 pounds of ballast.
Sixty-six thousand feet, 1880
pounds for balloon and 1900 for
ballast.
Seventy thousand feet, 4,3OO pounds
for balloon and $500 pounds of
ballast.
Seventy-three thousand feet, 1900
pounds for balloon and 1900 for
ballast.
Theoretical Factors Enter.
Beyond this, DR.. Tuckerman points
out, everything is theoretical, but the
increase of necessary balloon weight
and ballast goes up very rapidly. Thus
at 10000 feet a balloon weighing a
minimum of II, 900 pounds and carry
ing 4,200 pounds Of ballast would be
required. For 5000 feet the require
ments would be a balloon weighing
22,3o0 pounds and carrying 1900
pounds of ballast. It requires stretch
Of the imagination to conceive Of
going through the clouds with ap-
paratus weighing close to IS tons.
Henceforth the figures as calculated
by DR.. Tuckerman are:
One hundred and ten thousand
feet, $4,000 pounds and 1900 pounds.
One hundred and twenty thousand
feet, 69,40o pounds and $4,000 pounds
One hundred and thirty thousand
feet. 123.9o0 pounds and 40.6o0
pounds.
One hundred and forty thousand
feet. 22o,22o pounds and 1890
pounds.
One hundred and fifty thousand
feet. 393,700 pounds and 128,200
pounds.
Thus, for an ascent of approM-
mately 80 miles the combined weights
would be close to $500 tons, verita-
BILE aerial Leviathan. Without the
balloon size ascent to the higher levels
would be impossible, and without the
ballast it would be impossible to get
down alive.
Russians Discarded Ballast.
The unfortunate Russian balloon
lists, DR.. Tuckerman points out, made
the mistake Of throwing away ballast
in order to add a few thousand feet
to their record, with the result that
when they started to come down they
had no brakes" with which to ease
their collision with the earth.
The computations are based on pres
ent materials used in balloon-making
and present knowledge of conditions
within the stratosphere. But any de-
velopments which can be foreseen
hardly would add more than mile or
two, at the most, to the possibilities.
One proposal is that the ballast be
carried in the form of liquid hydrogen,
and if this should prove feasible some
further progress might be expected.
Balloon Types Vary.
A serious problem in conquering the
stratosphere, Bureau of Standards
physicists point out, is the choice be-
tween the closed and the open balloon.
When the big gas bag is closed on the
bottom, as was the case with the Ex-
plorer, there is the danger of tearing,
due to the pressure of the atmosphere
without on the lighter hydrogen with
in during the filled process. This is
exactly what happened to the Ex-
plorer.
With the open-bottom balloon,
where there is direct contact between
hydrogen and oxygen, there is always
the danger of an explosion. This also
happened to the Explorer once its bot
tom was torn away.
Among the solutions offered Is that
layer of helium or nitrogen, both
lighter than air, be placed just below
the hydrogen, thus sealing of the
lighter gas from the oxygen All these