flying machines-第22章

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action　invite　disaster。　This　is　true　of　aviators　the　same

as　it　is　of　railroaders；　men　who　work　in　dynamite　mills；

etc。　But　in　nearly　every　instance　the　responsibility　rests

with　the　individual；　not　with　the　system。　There　are

some　men　unfitted　by　nature　for　aviation；　just　as　there

are　others　unfitted　to　be　railway　engineers。







CHAPTER　XVI。



RADICAL　CHANGES　BEING　MADE。



Changes；　many　of　them　extremely　radical　in　their　nature；

are　continually　being　made　by　prominent　aviators；

and　particularly　those　who　have　won　the　greatest　amount

of　success。　Wonderful　as　the　results　have　been　few　of

the　aviators　are　really　satisfied。　Their　successes　have

merely　spurred　them　on　to　new　endeavors；　the　ultimate

end　being　the　development　of　an　absolutely　perfect　aircraft。



Among　the　men　who　have　been　thus　experimenting

are　the　Wright　Brothers；　who　last　year　（1909）　brought

out　a　craft　totally　different　as　regards　proportions　and

weight　from　the　one　used　the　preceding　year。　One

marked　result　was　a　gain　of　about　3　1/2　miles　an　hour　in

speed。



Dimensions　of　1908　Machine。



The　1908　model　aeroplane　was　40　by　29　feet　over　all。

The　carrying　surfaces；　that　is；　the　two　aerocurves；　were

40　by　6　feet；　having　a　parabolical　curve　of　one　in　twelve。

With　about　70　square　feet　of　surface　in　the　rudders；　the

total　surface　given　was　about　550　square　feet。　The

engine；　which　is　the　invention　of　the　Wright　brothers；

weighed；　approximately；　200　pounds；　and　gave　about　25

horsepower　at　1；400　revolutions　per　minute。　The　total

weight　of　the　aeroplane；　exclusive　of　passenger；　but

inclusive　of　engine；　was　about　1；150　pounds。　This　result

showed　a　lift　of　a　fraction　over　2　1/4　pounds　to　the　square

foot　of　carrying　surface。　The　speed　desired　was　40

miles　an　hour；　but　the　machine　was　found　to　make　only

a　scant　39　miles　an　hour。　The　upright　struts　were

about　7/8…inch　thick；　the　skids；　2　1/2　by　1　1/4　inches　thick。



Dimensions　of　1909　Machine。



The　1909　aeroplane　was　built　primarily　for　greater

speed；　and　relatively　heavier；　to　be　less　at　the　mercy

of　the　wind。　This　result　was　obtained　as　follows：　The

aerocurves；　or　carrying　surfaces；　were　reduced　in　dimensions

from　40　by　6　feet　to　36　by　5　1/2　feet；　the　curve

remaining　the　same；　one　in　twelve。　The　upright　struts

were　cut　from　seven…eighths　inch　to　five…eighths　inch；　and

the　skids　from　two　and　one…half　by　one　and　one…quarter

to　two　and　one…quarter　by　one　and　three…eighths　inches。

This　result　shows　that　there　were　some　81　square　feet

of　carrying　surface　missing　over　that　of　last　year's

model。　and　some　25　pounds　loss　of　weight。　Relatively；

though；　the　1909　model　aeroplane；　while　actually　25

pounds　lighter；　is　really　some　150　pounds　heavier　in　the

air　than　the　1908　model；　owing　to　the　lesser　square

feet　of　carrying　surface。



Some　of　the　Results　Obtained。



Reducing　the　carrying　surfaces　from　6　to　5　1/2　feet

gave　two　resultsfirst；　less　carrying　capacity；　and；　second；

less　head…on　resistance；　owing　to　the　fact　that　the

extent　of　the　parabolic　curve　in　the　carrying　surfaces

was　shortened。　The　〃head…on〃　resistance　is　the　retardance

the　aeroplane　meets　in　passing　through　the　air；

and　is　counted　in　square　feet。　In　the　1908　model　the

curve　being　one　in　twelve　and　6　feet　deep；　gave　6　inches

of　head…on　resistance。　The　plane　being　40　feet　spread；

gave　6　inches　by　40　feet；　or　20　square　feet　of　head…on

resistance。　Increasing　this　figure　by　a　like　amount　for

each　plane；　and　adding　approximately　10　square　feet　for

struts；　skids　and　wiring；　we　have　a　total　of　approximately；

50　square　feet　of　surface　for　〃head…on〃　resistance。



In　the　1909　aeroplane；　shortening　the　curve　6　inches

at　the　parabolic　end　of　the　curve　took　off　1　inch　of

head…on　resistance。　Shortening　the　spread　of　the　planes

took　off　between　3　and　4　square　feet　of　head…on　resistance。

Add　to　this　the　total　of　7　square　feet；　less　curve

surface　and　about　1　square　foot；　less　wire　and　woodwork

resistance；　and　we　have　a　grand　total　of；　approximately；

12　square　feet　of　less　〃head…on〃　resistance　over

the　1908　model。



Changes　in　Engine　Action。



The　engine　used　in　1909　was　the　same　one　used　in

1908；　though　some　minor　changes　were　made　as

improvements；　for　instance；　a　make　and　break　spark　was

used；　and　a　nine…tooth；　instead　of　a　ten…tooth　magneto

gear…wheel　was　used。　This　increased　the　engine　revolutions

per　minute　from　1；200　to　1；400；　and　the　propeller

revolutions　per　minute　from　350　to　371；　giving　a　propeller

thrust　of；　approximately；　170　foot　pounds　instead

of　153；　as　was　had　last　year。



More　Speed　and　Same　Capacity。



One　unsatisfactory　feature　of　the　1909　model　over

that　of　1908；　apparently；　was　the　lack　of　inherent　lateral

stability。　This　was　caused　by　the　lesser　surface　and

lesser　extent　of　curvatures　at　the　portions　of　the

aeroplane　which　were　warped。　This　defect　did　not　show　so

plainly　after　Mr。　Orville　Wright　had　become　fully

proficient　in　the　handling　of　the　new　machine；　and　with

skillful　management；　the　1909　model　aeroplane　will　be

just　as　safe　and　secure　as　the　other　though　it　will　take

a　little　more　practice　to　get　that　same　degree　of　skill。



To　sum　up：　The　aeroplane　used　in　1909　was　25

pounds　lighter；　but　really　about　150　pounds　heavier　in

the　air；　had　less　head…on　resistance；　and　greater

propeller　thrust。　The　speed　was　increased　from　about　39

miles　per　hour　to　42　1/2　miles　per　hour。　The　lifting

capacity　remained　about　the　same；　about　450　pounds

capacity　passenger…weight；　with　the　1908　machine。　In　this

respect；　the　loss　of　carrying　surface　was　compensated　for

by　the　increased　speed。



During　the　first　few　flights　it　was　plainly　demonstrated

that　it　would　need　the　highest　skill　to　properly

handle　the　aeroplane；　as　first　one　end　and　then　the　other

would　dip　and　strike　the　ground；　and　either　tear　the　canvas

or　slew　the　aeroplane　around　and　break　a　skid。



Wrights　Adopt　Wheeled　Gears。



In　still　another　important　respect　the　Wrights；　so　far

as　the　output　of　one　of　their　companies　goes；　have　made

a　radical　change。　All　the　aeroplanes　turned　out　by　the

Deutsch　Wright　Gesellschaft；　according　to　the　German

publication；　_Automobil…Welt_；　will　hereafter　be　equipped

with　wheeled　running　gears　and　tails。　The　plan　of　this

new　machine　is　shown　in　the　illustration　on　page　145。

The　wheels　are　three　in　number；　and　are　attached　one

to　each　of　the　two　skids；　just　under　the　front　edge　of

the　planes；　and　one　forward　of　these；　attached　to　a　cross…

member。　It　is　asserted　that　with　these　wheels　the

teaching　of　purchasers　to　operate　the　machines　is　much

simplified；　as　the　beginners　can　make　short　flights　on

their　own　account　without　using　the　starting　derrick。



This　is　a　big　concession　for　the　Wrights　to　make；　as

they　have　hitherto　adhered　stoutly　to　the　skid　gear。

While　it　is　true　they　do　not　control　the　German　company

producing　their　aeroplanes；　yet　the　nature　of　their

connection　with　the　enterprise　is　such　that　it　may　be

taken　for　granted　no　radical　changes　in　construction

would　be　made　without　their　approval　and　consent。



Only　Three　Dangerous　Rivals。



Official　trials　with　the　1909　model　smashed　many　records

and　leave　the　Wright　brothers　with　only　three　dangerous

rivals　in　the　field；　and　with　basic　patents　which

cover　the　curve；　warp　and　wing…tip　devices　found　on

all　the　other　makes　of　aeroplanes。　These　three　rivals

are　the　Curtiss　and　Voisin　biplane　type　and　the　Bleriot

monoplane　pattern。



The　Bleriot　monoplane　is　probably　the　most　dangerous

rival；　as　this　make　of　machine　has　a　record　of　54

miles　per　hour；　has　crossed　the　English　channel；　and

has　lifted　two　passengers　besides　the　operator。　The　latest　type

of　this　machine　only　weighs　771。61　pounds　complete；

without　passengers；　and　will　lift　a　total　passenger

weight　of　462。97　pounds；　which　is　a　lift　of　5。21　pounds

to　the　square　foot。　This　is　a　better　result　t