VARIOUS FORMS OF FLYING MACHINES.
There are three distinct and radically different forms
of flying machines. These are:
Aeroplanes, helicopters and ornithopers.
Of these the aeroplane takes precedence and is used
almost exclusively by successful aviators, the helicopters
and ornithopers having been tried and found lacking in
some vital features, while at the same time in some
respects the helicopter has advantag
s not found in the
What the Helicopter Is.
The helicopter gets its name from being fitted with
vertical propellers or helices (see illustration) by the
action of which the machine is raised directly from the
ground into the air. This does away with the necessity
for getting the machine under a gliding headway before
it floats, as is the case with the aeroplane, and consequently
the helicopter can be handled in a much smaller
space than is required for an aeroplane. This, in many
instances, is an important advantage, but it is the only
one the helicopter possesses, and is more than overcome
by its drawbacks. The most serious of these is that the
helicopter is deficient in sustaining capacity, and requires
too much motive power.
Form of the Ornithopter.
The ornithopter has hinged planes which work like
the wings of a bird. At first thought this would seem
to be the correct principle, and most of the early experimenters
conducted their operations on this line. It
is now generally understood, however, that the bird in
soaring is in reality an aeroplane, its extended wings
serving to sustain, as well as propel, the body. At any
rate the ornithoper has not been successful in aviation,
and has been interesting mainly as an ingenious toy.
Attempts to construct it on a scale that would permit
of its use by man in actual aerial flights have been far
Three Kinds of Aeroplanes.
There are three forms of aeroplanes, with all of which
more or less success has been attained. These are:
The monoplane, a one-surfaced plane, like that used
The biplane, a two-surfaced plane, now used by the
Wrights, Curtiss, Farman, and others.
The triplane, a three-surfaced plane This form is
but little used, its only prominent advocate at present
being Elle Lavimer, a Danish experimenter, who has not
thus far accomplished much.
Whatever of real success has been accomplished in
aviation may be credited to the monoplane and biplane,
with the balance in favor of the latter. The monoplane
is the more simple in construction and, where weight-
sustaining capacity is not a prime requisite, may
probably be found the most convenient. This opinion is
based on the fact that the smaller the surface of the
plane the less will be the resistance offered to the air,
and the greater will be the speed at which the machine
may be moved. On the other hand, the biplane has a
much greater plane surface (double that of a monoplane
of the same size) and consequently much greater weight-
Differences in Biplanes.
While all biplanes are of the same general construction
so far as the main planes are concerned, each aviator
has his own ideas as to the "rigging."
Wright, for instance, places a double horizontal rudder
in front, with a vertical rudder in the rear. There
are no partitions between the main planes, and the
bicycle wheels used on other forms are replaced by skids.
Voisin, on the contrary, divides the main planes with
vertical partitions to increase stability in turning; uses
a single-plane horizontal rudder in front, and a big box-
tail with vertical rudder at the rear; also the bicycle
Curtiss attaches horizontal stabilizing surfaces to the
upper plane; has a double horizontal rudder in front,
with a vertical rudder and horizontal stabilizing surfaces
in rear. Also the bicycle wheel alighting gear.