The Rock Island Argus and daily union. (Rock Island, Ill.) 1920-1923, 1922-04-21
Frederick Haskin's Letter
tssesal Correspondence Arxus1
Forerunner of the Aerial FIivver
tsbecal Correspondents OF The Arg

small, safe plane, extremely low
powered, which the average man
could afford and operate On many
occa sions, such a machine could he
operated without the use of power
when at sufficient attitudes TO take
advantage of the winds which are
encountered more frequently hig1
In the air. Also, a sufficiently skill.
full operator of such an aerial fiv-
yer could use 1t as a glider nearer
to the ground when conditions
made it 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 vary-
ing reflection of the suns heat
causes the air TO rise quite genc.-
ally over some areas, with compea-
sating descending airs over other
portions of ground. Inequalities Of
the surface-hills and mountains
force moving air into an upward
direction. 1t is these air currents
which the skilled manipulation OF
glider takes advantage of in order
to climb in the air above his start
ing point.
Earlier glider records were re-
markable, but were beaten by Harth
in his trip made last autumn One
German glider flew about six miles.
and in the course of the flight rose
800 feet above its starting point.
But the landing point was fully
1900 feet below the starting point,
and the fight lasted a much short
er time than Harth eventually WIS
able to accomplish. Later on an
other German kept a pOWerless
plane in the air about Is minutes.
The great accomplishment made
by Harth, though, was not so
much the time record he made and
the actual ascent into the air with
out power, as the fact that the
plane from start to finish of the
flight, '1ost 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 NOV
able wing tips used Without any
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 gusts. and changing di-
rection often. The machine headed
into the wind whenever such a
change came. So slight was the
inclination of the ground that OBJ
servers of the flight asserted that
upward currents of wind had little
to do with the climbing Of the
machine
Little Power Needed.
About a twenty-mile wind was
blowing when this noteworthy feat
was performed. AerOnaUtical eX-
perts say that very little power for
artificial propulsion would be need
ed in light plane built along the
lines of a soaring bird to give the
same lift as that acquired from
moderate wind.
The wing loading" of the Ger
man elders is little. By this term
is meant the weight sustained by
each square foot of wing area when
the machine is in fight. The glid-
ers best known have wing areas
ranging from 100 to IT'S square feet.
Assuming that the average flyer
weighs 165 pounds, the wing load
ing varies from about two pounds
per square foot to one pound. The
Harth machine weighs about an
even hundred pounds, probably the
lightest of the gliders Having a
wing area of 165 square feet, the
wing loading is just about one and
a half pounds per square foot when
a 165-pound man is being carried
Naturally, the development Of
the glider is as much in its infCuCy
as power driven airplanes were in
the days of the first machine. which
was pushed from the rear by
propellers. Nineteen years have
witnessed an amazing development
since the pioneering done by The
Wright brothers in the face of pub
lie ridicule. The next decade may
witness the merging of the glider
into the Iow-powered, low-priccd
flying machine within the reach Of
the ordinary pocketbook It would
not be fast. but would have the
compensating advantages Of ascend
ing into the air at very low speed
and the ability to land almost any
where at about the same velocity,
instead of requiring regular flying
fields for both starting and ending
flights.