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shown in Fig。 30; which has a deep concave directly

behind the forward margin; as at A; so

that when the plane is at an angle of about 22

degrees; a horizontal line; as B; passing back from

the nose; touches the incurved surface of the plane

at a point about one…third of its measurement

back across the plane。



_Fig。 30。 One of the Monstrosities_



This form is an exact copy of the wing of an

actual bird; but it belongs; not to the soaring;

but to the class which depends on flapping wings;

and as such it cannot be understood why it should

be used for soaring machines; as all aeroplanes

are。



The foregoing instances of construction are

cited to show how wildly the imagination will

roam when it follows wrong ideals。



THE TAIL AS A MONITOR。The tendency of the

center of pressure to change necessitates a correctional

means; which is supplied in the tail of

the machine; just as the tail of a kite serves to

hold it at a correct angle with respect to the wind

and the pull of the supporting string。









CHAPTER VII



ABNORMAL FLYING STUNTS AND SPEEDS





〃PEQUOD; a Frenchman; yesterday repeatedly

performed the remarkable feat of flying with the

machine upside down。 This exhibition shows

that the age of perfection has arrived in flying

machines; and that stability is an accomplished

fact。〃News item。





This is quoted to show how little the general

public knows of the subject of aviation。 It correctly

represents the achievement of the aviator;

and it probably voiced the sentiment of many

scientific men; as well as of the great majority of

aviators。



A few days afterwards; the same newspaper

published the following:





〃Lieutenant ; while experimenting yesterday

morning; met his death by the overturning

of his machine at an altitude of 300 meters。

Death was instantaneous; and the machine was

completely destroyed。〃



The machines used by the two men were of the

same manufacture; as Pequod used a stock machine

which was strongly braced to support the

inverted weight; but otherwise it was not unlike

the well known type of monoplane。



Beachy has since repeated the experiment with

a bi…plane; and it is a feat which has many imitators;

and while those remarkable exhibitions

are going on; one catastrophe follows the other

with the same regularity as in the past。



Let us consider this phase of flying。 Are they

of any value; and wherein do they teach anything

that may be utilized;



LACK OF IMPROVEMENTS IN MACHINES。It is remarkable

that not one single forward step has

been taken to improve the type of flying machines

for the past five years。 They possess the same

shape; their stabilizing qualities and mechanism

for assuring stability are still the same。



MEN EXPEDITED; AND NOT THE MACHINE。The

fact is; that during this period the man has been

exploited and not the machine。 Men have learned;

some few of them; to perform peculiar stunts;

such as looping the loop; the side glide; the drop;

and other features; which look; and are; hazardous;

all of which pander to the sentiments of the spectators。



ABNORMAL FLYING OF NO VALUE。It would be

too broad an assertion to say that it has absolutely

no value; because everything has its use

in a certain sense; but if we are to judge from

the progress of inventions in other directions;

such exhibitions will not improve the art of building

the device; or make a fool…proof machine。



Indeed; it is the very thing which serves as a

deterrent; rather than an incentive。 If machines

can be handled in such a remarkable manner; they

must be; indeed; perfect! Nothing more is

needed! They must represent the highest structural

type of mechanism!



That is the idea sought to be conveyed in the

first paragraph quoted。 It is pernicious; instead

of praiseworthy; because it gives a false impression;

and it is remarkable that even certain scientific

journals have gravely discussed the perfected

(?) type of flying machine as demonstrated

by the experiments alluded to。



THE ART OF JUGGLING。We may; occasionally;

see a cyclist who understands the art of balancing

so well that he can; with ease; ride a machine

which has only a single wheel; or he can; with a

stock bicycle; ride it in every conceivable attitude;

and make it perform all sorts of feats。



It merely shows that man has become an

expert at juggling with a machine; the same as he

manipulates balls; and wheels; and other artifices;

by his dexterity。



PRACTICAL USES THE BEST TEST。The bicycle

did not require such displays to bring it to perfection。

It has been the history of every invention

that improvements were brought about; not

by abnormal experiments; but by practical uses

and by normal developments。



The ability of an aviator to fly with the machine

in an inverted position is no test of the machine's

stability; nor does it in any manner prove that

it is correctly built。 It is simply and solely a

juggling featsomething in the capacity of a certain

man to perform; and attract attention because

they are out of the ordinary。



CONCAVED AND COXVEX PLANES:They were performed

as exhibition features; and intended as

such; and none of the exponents of that kind of

flying have the effrontery to claim that they prove

anything of value in the machine itself; except

that it incidentally has destroyed the largely

vaunted claim that concaved wings for supporting

surfaces are necessary。



HOW MOMENTUM IS A FACTOR IN INVERTED FLYING。

When flying 〃upside down;〃 the convex

side of the plane takes the pressure of the air;

and maintains; so it is asserted; the weight of the

machine。 This is true during that period when

the loop is being made。 The evolution is made

by first darting down; as shown in Fig。 31; from

the horizontal position; 1; to the position 2; where

the turn begins。



_Fig。 31。 Flying upside down。_



TURNING MOVEMENT。Now note the characteristic

angles of the tail; which is the controlling

factor。 In position 1 the tail is practically

horizontal。 In fact; in all machines; at

high flight; the tail is elevated so as to give little

positive angle of incidence to the supporting

planes。



In position No。 2; the tail is turned to an angle

of incidence to make the downward plunge; and

when the machine has assumed the vertical; as in

position 3; the tail is again reversed to assume

the angle; as in 1; when flying horizontally。



At the lower turn; position 4; the tail is turned

similar to the angle of position 2; which throws

the rear end of the machine down; and as the

horizontal line of flight is resumed; in an inverted

position; as in position 4; the tail has the same

angle; with relation to the frame; as the supporting

planes。



During this evolution the engine is running; and

the downward plunge develops a tremendous

speed; and the great momentum thus acquired;

together with the pulling power of the propeller

while thus in flight; is sufficient to propel it along

horizontally; whatever the plane surface curve; or

formation may be。



It is the momentum which sustains it in space;

not the air pressure beneath the wings; for

reasons which we have heretofore explained。

Flights of sufficient duration have thus been made

to prove that convex; as well as concave surfaces

are efficient; nevertheless; in its proper place we

have given an exposition of the reasoning which

led to the adoption of the concaved supporting

surfaces。



WHEN CONCAVED PLANES ARE DESIRABLE。

Unquestionably; for slow speeds the concaved wing

is desirable; as will be explained; but for high

speeds; surface formation has no value。 That is

shown by Pequod's feat。



THE SPEED MANIA。This is a type of mania

which pervades every field of activity in the building

of aeroplanes。 Speed contests are of more

importance to the spectators on exhibition

grounds than stability or durability。 Builders

pander to this; hence machines are built on lines

which disregard every consideration of safety

while at normal flight。



USES OF FLYING MACHINES。The machine as

now constructed is of little use commercially。

Within certain limitations it is valuable for scouting

purposes; and attempts have been made to

use it commercially。 But the unreliable character

of its performances; due to the many elements

which are necessary to its proper working; have

operated against it。



PERFECTION IN MACHINES MUST COME BEFORE

SPEED。Contrary to every precept in the building

of a new article; the attempt is made to make

a machine with high speed; which; in the very

nature of things; operates against its improvement。

The opposite lack of speedis of far

greater utility at this stage of its development。



THE RANGE OF ITS USE。The subject might be

illustrated by assuming that we have a line running

from A

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