Perth Amboy evening news., 1922-04-18
F~ORERUNNER OF AERIAL
FLIVVER is NOW in u. S.
Daily Letter by Frederic j. Haskin

| the air. Also. q sufficiently skillful op'
| orator of such an aerial hivve
| could use it as a glider nearer "a
the ground when conditions made II
possible.
Winds Blowing Upward
Winds blowing in a general up
ward direction are recorded with
more frequently than is ordinarily
believed. The coloring of the ground
with the consequent varying renee
ton of the suns heat, causes n air
to rise quite generally over some
areas, with compromising descend
ing airs ove other portions or
ground. Inequalities of the surface
hills and mountains-force NOV
ing air into an upward direction. 1t
is these air currents which the
skilled manipulator of a glider takes
advantage of in order to climb In
the air above his starting point.
Earlier glider records were re-
markable. but were beaten by Harth
in his trip made last autumn. One
German glider few about six miles,
and in the course of the flight rose
500 feet above its starting point.
But the landing point was fully
1900 feet below the starting point,
and the fight lasted a much shorter
time than Harth eventually was
able to accomplish. Later on an
other German kept powsrlsss
plane in the air about fifteen
minutes.
The great accomplishment made
by Harth, though, was not so much
the time record he made and the
actual ascent into the air without
power, as the fact that the plane
from start TO finish Of the fight,
lost altitude" or came down, at the
rate of only about two feet a
minute.
The machine used by Harth did
not have a rudder to guide it. This
had been dispensed with, and nova
BILE wing tips used. Without n
effort on the part of the aviator. the
Harth machine heads into the wind
when it changes direction. On the
day when his great record was made
the wind was said to be blowing in
The machine headed into the wind
whenever such a change came. So
slight was the inclination of the
ground that observers of the flight
asserted that upward currents of
wind had little to do with the climb
ing Of the machine.
Little Power Needed
About a twenty-mile wind was
blowing when this noteworthy feat
was performed. Aeronautical ex-
rerts say that very little power for
artificial propulsion would be needed
lines of a soaring bird to give the
same lift as that acquired from a
moderate wind.
The wing loading" of the Ger
man gliders is little. By this term
il meant the weight sustained by
each square foot of wing area when
the machine is in flight. The gliders
best known have wing areas rang
ing from $50 to IT'S square feet. AS
Stunning that the average flyer weighs
1855 pounds. the wing loading varies
from about two pounds per square
foot to one pound. The Harth ma
chine weighs about an even hundred
pounds, probably the highest Of the
elders. Having a wing area of 16s
square feet, the wing loading is just
about one and one-half pounds per
square foot when a 165 pound mar
Is being carried.
Naturally, the development of the
glider Ii as much in its infancy al
power driven airplanes were in the
days of the first machines, which
was pushed" from the rear by pro.
pellers. Nineteen years have wit
messed an amazing development
since the pioneering done by tn,
Wright brothers In the face of pub
lie ridicule. The next decade maj
witness the merging of the glider in
to the low-powered. low-priced fly
ing machine within the reach Of tn,
ordinary pocketbook. 1t would no
be fast. but would have the com,
~pensating advantages Of ascending
into the air at very low speed ant
the ability to land almost anywher,
at about the same velocity. insteas
of requiring regular flying fields fol
starting and ending flights.