Omaha daily bee., 1909-05-02
Next Week---Dixon County

sorts. Most of them were OF the simple
form. Others were more ambitious and
contrived so that the operator can make
certain variations of flight during his
glide. ~
In the inner workshop, or the toolshop,
as it Is called. another interesting process
was going on, the making of aeroplane
propellers. In this each MAJ follows his
own ideas.
One man uses metal for the blades and
mounts them on steel arms. Another
uses wood for the blades, but has it cut
in tiny narrow strips and mounted on
metal, perhaps brass or bronze. while
others cut the whole, blades and arms
complete, out Of one piece of wood, giving
1t the necessary twist as he goes on,
Others again face their wood with thin
sheets of metal, while others wrap the
blades with canvas, and still others. per-
haps 10 make sure OF being right. do
both And each has a good and substan-
tial theory for his method.
Art In Making screw.
But whatever method Is favored there
appears to be much art In the making
OF the screw. The blades must have a
wonderful twist which runs ~throuEhout
their length. But just what that twist is
to be is one OF the problems, for every
thing depends on the thrust against the
air that that twist causes.
In some mysterious way the amount of
the twist has to depend on the length OF
the blades and also upon the speed re-
quired. But just how is what each OK.
perimenter is trying TO find out, for II APP
pears to be varied also by each particular
design or sine OF apparatus and Is inti-
mately mixed up with problems Of the
relation of speed to the total amount Of
supporting surface.
Il Ia demonstrated thar the faster you
fly the smaller the apparatus need be. But
whatever size the apparatus Is IL has got
to travel at sons certain speed OF It won't
fly at all. This explained the use OF that
seeming instrument of terror, away out in
the infleld, the catapult, which shoots the
machines into the air.
II is not 20 much the shooting into the
cir that is necessary as the initial speed.
Hardly any machine, one is told, can fly
at all at a less speed than about thirty
miles an hour, and 1t must get that speed
somehow before 1t Gan begin. So the cata-
pult gives It a thirty miles an hour push,
These are some OF the difficulties that
cause those disappointing delays. AS soon
as a flying machine is assembled It Is
confidently expected that It is going to fly
But in truth It seems that the completion
OF the machine is only the beginning OF 1t.
Bit by bit the problem has to be con-
quered for each particular machine. And
It may be that the machine will be made
over again once or twice before It IL got
&C erect. First, the screws prove to have a
urrnu rifob and the sliqhtaSt alteration
means new screws. Then the engine proves
too weak or perhaps only too skittish. A
hundred little things crop up that have to
be altered even to allow OF the first ele-
mentary stage of flying. getting into the
air.
OF the aeroplanes, themselves, they are
an interesting study, for no two Of them
are alike, and each illustrates some prin-
ciple or idea. Most OF them are aeroplanes
OF the biplane, or two surface type, but one
is a triplane, and the parts are also there
of a monoplane, which Is of the helicopter
type, that is, 1t lifts with its propellers as
we'll as travels with them, and therefore
has to have horizontal propellers as well
as vertical ones.
The different machines IN the aerofac-
tory reveal the many different ways by
which the various inventors expect 20
make turns to right or left ana steer up
and down. Some have rudders far out be-
hind. acting like helms OF a ship. Others
have the little vertical planes used for
this purpose close up to the main body.
But the greatest problem of all is what
is called stabilltyI that which keeps the
machine from turning turtle, or topping
over backward.
On a bicycle one has only to balance
sideways. but on a flying machine one
has to balance both ways, back and front,
as well as sideways. The danger Of fitting
sideways IL averted by little weights on
the ends OF the big planes, and which
are worked with the rapidity OF thought
by a lever. Another aeronaut believes that
the lever cannot be quick enough 30 he
tries TO make II automatic by having the
operators seat pivoted and connected with
the wingiets. so that when the aviator feels
himself going dangerously over to one side
he instinctiveiy throws himself in the oppo-
site direction, and working the winslets
BY that act will light the machina-