The evening times., 1896-08-05
MAN ALMOST READY TO FLY
Aerial Navigation Will Soon
Become a Reality.
HARD PROBLEMS SOLVED
chftf Dific6ihes,H Have Been over
come and tise Aiipr Ones VIII Soon
Give Way TO Science-AustraIia
Claims the Honor of Latest Discov-
cries In This Mode of Travel.


1t will not be many years before fond
young girl will be able TO take her lover at
his word when he says; Fly with me-
They will unfold their wings and fly away,
the ira,e father viii have 10 lily also If
he wants to catch them
The great difficulties in the way of
aerial flight have already been solved;
|. those which bar success are minor ones and
must soon succumb to the efforts OF the
interchangeable" enthusiasts, who are labor
ing for that result.
The honor Tor the latest discovery af-
fecting the problem, of air-flight belongs
to Hargrave, OF Australia
He must be added to the roll of honor on
whicil-is inscribed the names of Langley,
MaxiWs LeIieDthal and Chanute.
The principle which is the basis of the
modern flying, machine bears the same
analogy to bird flight as a carriage on
wheels bears to pcdestrial locomotion !.
TheswiDg action ofIa bird, flying fairly
horizpDtally, when dssected, is found to
consist of two distinct elements, one a
propulsion .forwariiby back pressure on
the air, and the other a support furnished
by the upward component of the air
which 'is'forced. against the inclined front
plans gf the wing.
STABILITY A NECESSITY.
In the modern flying machine 1t has
been found more convenient to deal with
these separately, SO that II now consists
radically of plane surface inclined at a
small angle, which may on the average he
taken as an incline OF in l3, together
with a rotating screw propeller, which
forces ,this- inclined plane through the
air. The principal requisites which then
remain for theisoccessful accomplishment
of flight under these circumstances are
stability and dirigibility or the aeropiane
under all circumstances, and such an eff
cheney OF the motor, compared with its
weight, as 10 furnish propulsion sufficieut
to support the aeroplane aud its passen-
gers.
The former part of this problem has been
separately studied by Langley and Lilien-
that and the latter by Maxim. Hargrave
has attacked both problems at once, and II
ises 10 be he will go down TO posterity
as the Newton OF air flight.
By approaching the moving aeroplane
from the kite principle, Hargraye has
constructed what is DOW found TO be the
most stable form Of aeroplane in exist
ence. From the very first he seems to
have recognized the strict analogy between
the srpport of moving inclined aero
plane and that of moorcd kite.
MODELLING FROM THE KITE.
II we cut the sitting of a kite, supply it
with . motor -to drive it horizontally, and
suspended so as to allow it to lie at the
Same angie as wlien moored, and imagine
the wind replaced by calm, relative
wind will he produced by the forward mo-
ton OF the aerUplaBe kite, which supports
it exactly as it was when moored by the
string
The solution of the problem of the best
m of kite thus Involves the simultane-
Gus solution of the best form OF aeroplane.
Ordinary kites-are unstable chiefly In
lateral direction, owing To the sharpness of
their edges aud oHargrave has remedied
this defect by .ipyepting the double-plane
or cellular kite, in which the closed-in sides
connecting the two planes insure lateral
stability by. developing an opposing side
pressure the moment the machine tends to
move sideways:
An open air space between the two
operates in some as yet mysterious way
upon the air currents SO as to cause stabii-
ity in a longitudinal direction, SO that
when it'll allowed to fan freely the cellular
kite drops. quietly and steadily without
any tendency to oscillatc or invert. This
kite forms the aeroplane basis OF the Har-
grave flyiRg machine. Several additions
to this will De made to enable it TO be
more effective and dirigible, such as NOV
able horizontal trent plane to direct it up
and down and regulate the inclination,
side wings to act as floats, rudders and
lateral directors. like the wings of the
soaring and sailing birds, and horizontal
stern and verticie rudder planes.
DIFFICULTIES TO OVERCOME.
The motive apparatus consists of
specially light engine, actuated by petrol
cum, and with the fine boiler tubes ar
ranged in such "a manner as to be packed
together in the smallest possible compass,
and yet easily reached for cleaning and
repairing. The whole of. the machinery is
placed in the central gap between the two
double planes, and works vertically ro-
tating screw fan placed astern.
Hargrave estimates that 1-2 horse
power is sufficient to. propel the aeroplane
so as to support the weight OF man and
together, and the entire weight
OF the engine does not exceed from thirty
to forty pounds. To secure extra stability
and support, single kite cell is placed
above the central gap at distance OF
about seven feet from it. The rigid
parts of the structure are all made of
hollow steel. and, i. the coverings OF bal
loon material.
The chief Difficulty In connection with
Hargrayc's MACHINE. will be in maintain.
Ing its balance when steered aainst or
with the wind, and in counteracung the
effects of the incessant variability which
Prof Langley has shown to be peculiarly
Of air motion.
Practice and experience alone will over
Come the former, while it is possible that
when the flying instinct is properly de-
veioped the variability will be an advan-
tage and the operator learn to soar like
the eagle of the Rockies and the condor
of the Andes.