New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1911-01-08

/ + not TIL one DcSlflS 10 take an luJ'It7l
in hving machines that he realizes what
wonderful thing the air is, and what strength
it has. OF course once in awhile one sees
chimncvpots blown off, and states scattering
from the roofs Of houses; but that IS only IN
great gales, which occur perhaps once or
twice a year But if one is going to take any
interest in flying, even if only as spectator
at an aviation meeting, 1t IS most important
10 have knowledge Of the subject And,
what is even more important, one must real
izc that a wind is hardly ever a steady, even
current Of air; but is generally made up Of a
series of gusts which to the man who Is fly
ing. act much the same As do the waves at
sea to a small boat.
The hving man is far worse of than the
sailor; for one can always see wave OF
water coming and handle the boat accord
inglv. whereas with an air wave one cannot
tell. till it has struck the machine, Just when
it is coming or how big and strong It IS going
TO be. II is one OF the troubles OF flying
men that the people who come to see them
hv do not know about these wind waves, and
50 expect them to fly in weather that is
really dangerous, although II may appear tine.
On a great open plain, miles and miles
wide, such as that over which the aviation
meetings at Rheims are held, there Is nothing
TO interfere with the wind, and consequently
it blows steadily, with hardly any gusts
or waves. It is then possible to fly in quite
strong winds. On the other hand on a
small ground. or where there are hills and
banks and trees all round, the wind, even
when blowing comparatively gently, comes
in dangerous waves, SwirlS, and cddieS, Just
like the cddicS and whlrlpools in a stream
Il. 1. L l.. f..
pcdc the flow OF water.
How to Ride Air Waves
NOV, to understand properly the effects
~ of these waves on an acrOplanc II Is
necessary first to understand that the ma
chine is held in the air because the pace at
which it is driven by its propeller produces
pressure under its wings, or planes, and this
pressure lifts it up. If it is driven faster,
it makes greater pressure, and naturally 1t
lifts higher Ii it is driven slower il makes
less pressure, and then it falls
1t is easy to understand that such heavy
thing as an aeroplanc will not change its
speed very quickly. Even a light mono
plane will weigh four hundred to five hun
drcd pounds, and one OF the big biplancS
may weigh anything between eight hundred
pounds and ton, and Of course when they
are flying they have great momentum.
Therefore, suppose a machine 10 be flying
at a speed Of thrty-hvc miles an hour over
the ground in gentle wind. and suppose 4
gust To meet it that is travelling ten miles
an hour faster than the wind in which 1t was
originally flying. What is the effect; The
machine cannot at once slow down; but
simply charges into that gust at thlrty-tlvc
miles an hour. Consequently, the pressure
on the wings is increased and the machine
promptly rises
But consider the effect of opposite con-
ditions. Suppose the machine had slowed
down in relation to the earth, 50 as TO get
to its proper flying speed in relation to that
gust OF wind. Presently it gets right
through the gust and into the lull the other
side Just as a boat will ride over wave
and fall into the trough between the waves
This time the effect is that it is flying too
slowly for the patch OF slow wind that fol-
lows the gust, and consequently the pressure
under the planes is decreased, and the ma
chine drops till il either hits the ground
lwhcn II may or may not be broken, accord
ing to the pilots skill in landing, or else
picks up It's speed again, and produces the
necessary pressure.
The sudden drop is most diSconccrtlng,
and l. the cause OF many accidents, cspc-
Clally to those who are comparative novlccs
rs INittpr- and "a, IL, not fy hiph enough Ia