flying machines-第33章

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of　this　court；　on　the　papers　presented；　to　enjoin。



〃The　requirements　in　patent　causes　for　the　issuance

of　an　injunction　pendente　litethe　validity　of　the　patent；

general　acquiescence　by　the　public　and　infringement

by　the　defendantsare　so　reasonably　clear　that　I　believe

if　not　probable　the　complainant　may　succeed　at　final

hearing；　and　therefore；　status　quo　should　be　preserved

and　a　preliminary　injunction　granted。



〃So　ordered。〃



Points　Claimed　By　Curtiss。



That　the　Herring…Curtiss　Co。　will　appeal　is　a　certainty。

Mr。　Emerson　R。　Newell；　counsel　for　the　company；

states　its　case　as　follows：



〃The　Curtiss　machine　has　two　main　supporting　surfaces；

both　of　which　are　curved　*　*　*　and　are　absolutely

rigid　at　all　times　and　cannot　be　moved；　warped　or

distorted　in　any　manner。　The　front　horizontal　rudder　is

used　for　the　steering　up　or　down；　and　the　rear　vertical

rudder　is　used　only　for　steering　to　the　right　or　left；　in

the　same　manner　as　a　boat　is　steered　by　its　rudder。　The

machine　is　provided　at　the　rear　with　a　fixed　horizontal

surface；　which　is　not　present　in　the　machine　of　the　patent；

and　which　has　a　distinct　advantage　in　the　operation

of　defendants'　machine；　as　will　be　hereafter　discussed。



Does　Not　Warp　Main　Surface。



〃Defendants'　machine　does　not　use　the　warping　of　the

main　supporting　surfaces　in　restoring　the　lateral　equilibrium；

but　has　two　comparatively　small　pivoted　balancing

surfaces　or　rudders。　When　one　end　of　the　machine

is　tipped　up　or　down　from　the　normal；　these　planes　may

be　thrown　in　opposite　directions　by　the　operator；　and

so　steer　each　end　of　the　machine　up　or　down　to　its

normal　level；　at　which　time　tension　upon　them　is　released

and　they　are　moved　back　by　the　pressure　of　the

wind　to　their　normal　position。



Rudder　Used　Only　For　Steering。



〃When　defendants'　balancing　surfaces　are　moved　they

present　equal　angles　of　incidence　to　the　normal　rush

of　air　and　equal　resistances；　at　each　side　of　the　machine；

and　there　is　therefore　no　tendency　to　turn　around　a

vertical　axis　as　is　the　case　of　the　machine　of　the　patent；

consequently　no　reason　or　necessity　for　turning　the　vertical

rear　rudder　in　defendants'　machine　to　counteract　any

such　turning　tendency。　At　any　rate；　whatever　may　be

the　theories　in　regard　to　this　matter；　the　fact　is　that

the　operator　of　defendants'　machine　does　not　at　any

time　turn　his　vertical　rudder　to　counteract　any　turning

tendency　clue　to　the　side　balancing　surfaces；　but　only

uses　it　to　steer　the　machine　the　same　as　a　boat　is

steered。〃



Aero　Club　Recognizes　Wrights。



The　Aero　Club　of　America　has　officially　recognized

the　Wright　patents。　This　course　was　taken　following　a

conference　held　April　9th；　1910；　participated　in　by　William

Wright　and　Andrew　Freedman；　representing　the

Wright　Co。；　and　the　Aero　Club's　committee；　of　Philip

T。　Dodge；　W。　W。　Miller；　L。　L。　Gillespie；　Wm。　H。　Page

and　Cortlandt　F。　Bishop。



At　this　meeting　arrangements　were　made　by　which

the　Aero　Club　recognizes　the　Wright　patents　and　will

not　give　its　section　to　any　open　meet　where　the　promoters

thereof　have　not　secured　a　license　from　the

Wright　Company。



The　substance　of　the　agreement　was　that　the　Aero

Club　of　America　recognizes　the　rights　of　the　owners　of

the　Wright　patents　under　the　decisions　of　the　Federal

courts　and　refuses　to　countenance　the　infringement　of

those　patents　as　long　as　these　decisions　remain　in　force。



In　the　meantime；　in　order　to　encourage　aviation；　both

at　home　and　abroad；　and　in　order　to　permit　foreign

aviators　to　take　part　in　aviation　contests　in　this　country

it　was　agreed　that　the　Aero　Club　of　America；　as　the

American　representative　of　the　International　Aeronautic

Federation；　should　approve　only　such　public　contests

as　may　be　licensed　by　the　Wright　Company　and　that

the　Wright　Company；　on　the　other　hand；　should　encourage

the　holding　of　open　meets　or　contests　where　ever　approved　as

aforesaid　by　the　Aero　Club　of　America

by　granting　licenses　to　promoters　who　make　satisfactory

arrangements　with　the　company　for　its　compensation

for　the　use　of　its　patents。　At　such　licensed　meet　any

machine　of　any　make　may　participate　freely　without

securing　any　further　license　or　permit。　The　details　and

terms　of　all　meets　will　be　arranged　by　the　committee

having　in　charge　the　interests　of　both　organizations。







CHAPTER　XXIV。



HINTS　ON　PROPELLER　CONSTRUCTION。



Every　professional　aviator　has　his　own　ideas　as　to　the

design　of　the　propeller；　one　of　the　most　important　features

of　flying…machine　construction。　While　in　many

instances　the　propeller；　at　a　casual　glance；　may　appear

to　be　identical；　close　inspection　will　develop　the　fact　that

in　nearly　every　case　some　individual　idea　of　the　designer

has　been　incorporated。　Thus；　two　propellers　of　the　two…

bladed　variety；　while　of　the　same　general　size　as　to

length　and　width　of　blade；　will　vary　greatly　as　to　pitch

and　〃twist〃　or　curvature。



What　the　Designers　Seek。



Every　designer　is　seeking　for　the　same　resultthe

securing　of　the　greatest　possible　thrust；　or　air　displacement；

with　the　least　possible　energy。



The　angles　of　any　screw　propeller　blade　having　a

uniform　or　true　pitch　change　gradually　for　every　increased

diameter。　In　order　to　give　a　reasonably　clear

explanation；　it　will　be　well　to　review　in　a　primary　way

some　of　the　definitions　or　terms　used　in　connection　with

and　applied　to　screw　propellers。



Terms　in　General　Use。



Pitch。The　term　〃pitch；〃　as　applied　to　a　screw　propeller；

is　the　theoretical　distance　through　which　it　would

travel　without　slip　in　one　revolution；　and　as　applied　to

a　propeller　blade　it　is　the　angle　at　which　the　blades　are

set　so　as　to　enable　them　to　travel　in　a　spiral　path　through

a　fixed　distance　theoretically　without　slip　in　one　revolution。



Pitch　speed。The　term　〃pitch　speed〃　of　a　screw

propeller　is　the　speed　in　feet　multiplied　by　the　number　of

revolutions　it　is　caused　to　make　in　one　minute　of　time。

If　a　screw　propeller　is　revolved　600　times　per　minute；

and　if　its　pitch　is　7　ft。；　then　the　pitch　speed　of　such　a

propeller　would　be　7x600　revolutions；　or　4200　ft。　per

minute。



Uniform　pitch。A　true　pitch　screw　propeller　is　one

having　its　blades　formed　in　such　a　manner　as　to　enable

all　of　its　useful　portions；　from　the　portion　nearest　the

hub　to　its　outer　portion；　to　travel　at　a　uniform　pitch

speed。　Or；　in　other　words；　the　pitch　is　uniform　when　the

projected　area　of　the　blade　is　parallel　along　its　full

length　and　at　the　same　time　representing　a　true　sector

of　a　circle。



All　screw　propellers　having　a　pitch　equal　to　their

diameters　have　the　same　angle　for　their　blades　at　their

largest　diameter。



When　Pitch　Is　Not　Uniform。



A　screw　propeller　not　having　a　uniform　pitch；　but

having　the　same　angle　for　all　portions　of　its　blades；　or

some　arbitrary　angle　not　a　true　pitch；　is　distinguished

from　one　having　a　true　pitch　in　the　variation　of　the　pitch

speeds　that　the　various　portions　of　its　blades　are　forced

to　travel　through　while　traveling　at　its　maximum　pitch

speed。



On　this　subject　Mr。　R。　W。　Jamieson　says　in　Aeronautics：



〃Take　for　example　an　8…foot　screw　propeller　having　an

8…foot　pitch　at　its　largest　diameter。　If　the　angle　is　the

same　throughout　its　entire　blade　length；　then　all　the　porions

of　its　blades　approaching　the　hub　from　its　outer　portion　would

have　a　gradually　decreasing　pitch。　The　2…foot

portion　would　have　a　2…foot　pitch；　the　3…foot　portion　a　3…

foot　pitch；　and　so　on　to　the　8…foot　portion　which　would

have　an　8…foot　pitch。　When　this　form　of　propeller　is

caused　to　revolve；　say　500　r。p。m。；　the　8…foot　portion　would

have　a　calculated　pitch　speed　of　8　feet　by　500　revolutions；

or　4；000　feet　per　min。；　while　the　2…foot　portion　would

have　a　calculated　pitch　speed　of　500　revolutions　by　2　feet；

or　1；000　feet　per　minute。



Effect　of　Non…Uniformity。



〃Now；　as　a