flying machines-第20节

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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　than　those

published　by　the　Wright　brothers；　the　best　noted　being

4。25　pounds　per　square　foot。



Other　Aviators　at　Work。



The　Wrights；　however；　are　not　alone　in　their　efforts

to　promote　the　efficiency　of　the　flying　machine。　Other

competent　inventive　aviators；　notably　Curtiss；　Voisin；

Bleriot　and　Farman；　are　close　after　them。　The　Wrights；

as　stated；　have　a　marked　advantage　in　the　possession　of

patents　covering　surface　plane　devices　which　have　thus

far　been　found　indispensable　in　flying　machine　construction。

Numerous　law　suits　growing　out　of　alleged　infringements

of　these　patents　have　been　started；　and

others　are　threatened。　What　effect　these　actions　will

have　in　deterring　aviators　in　general　from　proceeding

with　their　experiments　remains　to　be　seen。



In　the　meantime　the　four　men　namedCurtiss；　Voisin；

Bleriot　and　Farmanare　going　ahead　regardless　of

consequences；　and　the　inventive　genius　of　each　is　so　strong

that　it　is　reasonable　to　expect　some　remarkable　developments

in　the　near　future。



Smallest　of　Flying　Machines。



To　Santos　Dumont　must　be　given　the　credit　of　producing

the　smallest　practical　flying　machine　yet　constructed。

True；　he　has　done　nothing　remarkable　with　it

in　the　line　of　speed；　but　he　has　demonstrated　the　fact

that　a　large　supporting　surface　is　not　an　essential　feature。



This　machine　is　named　〃La　Demoiselle。〃　It　is　a　monoplane

of　the　dihedral　type；　with　a　main　plane　on　each

side　of　the　center。　These　main　planes　are　of　18　foot

spread；　and　nearly　6　1/2　feet　in　depth；　giving　approximately

115　feet　of　surface　area。　The　total　weight　is　242　pounds；

which　is　358　pounds　less　than　any　other　machine　which

has　been　successfully　used。　The　total　depth　from　front

to　rear　is　26　feet。



The　framework　is　of　bamboo；　strengthened　and　held

taut　with　wire　guys。



Have　One　Rule　in　Mind。



In　this　struggle　for　mastery　in　flying　machine　efficiency

all　the　contestants　keep　one　rule　in　mind；　and　this

is：



〃The　carrying　capacity　of　an　aeroplane　is　governed

by　the　peripheral　curve　of　its　carrying　surfaces；　plus　the

speed；　and　the　speed　is　governed　by　the　thrust　of　the

propellers；　less　the　'head…on'　resistance。〃



Their　ideas　as　to　the　proper　means　of　approaching

the　proposition　may；　and　undoubtedly　are；　at　variance；

but　the　one　rule　in　solving　the　problem　of　obtaining　the

greatest　carrying　capacity　combined　with　the　greatest

speed；　obtains　in　all　instances。







CHAPTER　XVII。



SOME　OF　THE　NEW　DESIGNS。



Spurred　on　by　the　success　attained　by　the　more　experienced

and　better　known　aviators　numerous　inventors

of　lesser　fame　are　almost　daily　producing　practical　flying

machines　varying　radically　in　construction　from

those　now　in　general　use。



One　of　these　comparatively　new　designs　is　the　Van

Anden　biplane；　made　by　Frank　Van　Anden　of　Islip；

Long　Island；　a　member　of　the　New　York　Aeronautic

Society。　While　his　machine　is　wholly　experimental；

many　successful　short　flights　were　made　with　it　last　fall

（1909）。　One　flight；　made　October　19th；　1909；　is　of　particular

interest　as　showing　the　practicability　of　an　automatic

stabilizing　device　installed　by　the　inventor。　The

machine　was　caught　in　a　sudden　severe　gust　of　wind

and　keeled　over；　but　almost　immediately　righted　itself；

thus　demonstrating　in　a　most　satisfactory　manner　the

value　of　one　new　attachment。



Features　of　Van　Anden　Model。



In　size　the　surfaces　of　the　main　biplane　are　26　feet

in　spread；　and　4　feet　in　depth　from　front　to　rear。　The

upper　and　lower　planes　are　4　feet　apart。　Silkolene

coated　with　varnish　is　used　for　the　coverings。　Ribs

（spruce）　are　curved　one　inch　to　the　foot；　the　deepest

part　of　the　curve　（4　inches）　being　one　foot　back　from　the

front　edge　of　the　horizontal　beam。　Struts　（also　of

spruce；　as　is　all　the　framework）　are　elliptical　in　shape。

The　main　beams　are　in　three　sections；　nearly　half　round

in　form；　and　joined　by　metal　sleeves。



There　i