,transcrib]'s ,note ,italic text display$ z3 italic ,bold text display$ z3 bold ,,le>n+ ,,to ,,fly ,,9 ,,! ,u4 ,s4 ,,army ,mc,graw-,hill ,book ,co4 ,inc4 ,,publi%]s ,,( ,,books ,,= ,coal ,age ,illu/ration3 ,decoration ,electric ,railway ,j\rnal ,electrical ,_w ,illu/ration3 ,decoration ,eng9e]+ ,news-,record ,am]ican ,ma*9i/ ,illu/ration3 ,decoration ,! ,contractor ,eng9e]+ ,m9+ ,j\rnal ,illu/ration3 ,decoration ,p[] ,metallurgical ,*emical ,eng9e]+ ,electrical ,m]*&is+ ,illu/ration3 ,a ,,gr\p ,,( ,u4,s4 ,,army ,,/ud5t ,,aviators4 ,frontispiece ,,le>n+ ,,to ,,fly ,,9 ,,! ,u4 ,s4 ,,army ,a ,,manual ,,( ,,aviation ,,practice ,,by ,e4 ,n4 ,,fales ,,=m]ly ,,assi/ant ,,pr(essor ,,( ,,me*anical ,,eng9e]+ ,,*air ,,( ,,a]onautics1 ,,univ]sity ,,( ,,ill9ois ,,fir/ ,,edition ,,second ,,impression ,mc,g,r,a,w-,,hill ,,book ,,company1 ,,inc4 #bci ,,we/ #ci,,? ,,/reet4 ,,new ,,york ,,london3 ,,hill ,,publi%+ ,,co41 ,,ltd4 #f #h ,,b\v]ie ,,/41 ,e4 ,c4 #aiag ,,copyright1 #aiag1 ,,by ,,! ,,mcgraw-,,hill ,,book ,,company1 ,,inc4 ,,! ,,maple ,,press ,,york ,,pa ,,preface ,?is book is prim>ily int5d$ = non-te*nical read]s2 & = ! /ud5t aviators :o1 call$ f non-te*nical occupations1 mu/ cram !mselves at %ort notice ) ! gi/ ( airplane fly+2 & :o mu/ omit ev]y?+ except ! out/&+ fundam5tals4 ,! desir$ ess5tials are "h giv5 )\t sacrific+ accuracy to brevity4 ,x has be5 necess>y to omit _m te*nical details ( int]e/ to ! a]onautical eng9e]1 to ^: ne$s o!r l>g] textbooks are adapt$ z a complete survey ( te*nical a]onautics4 ,9 brief1 ! book pres5ts ! ma9 pr9ciples ( aviation1 su* z ! aviator mu/ "k 9 ord] prop]ly to und]/& 8 airplane1 keep x tru$ up1 & op]ate x 9 cross-c\ntry flights z well z at ! fly+ field4 ,out ( ! #bjjj a]onautical books n[ 9 exi/5ce1 a few are adapt$ to use z textbooks = ! pres5t ne$1 b none give ! p>ticul> & abridg$ in=mation 9 tabloid =m su* z mu/ be adopt$ = ! be/ "t economy ( ^! /ud5ts4 ,x is by ! k9d p]mission ( ,pr(essor ,e4 ,a4 ,holbrook1 ,mr4 ,o4 ,s4 ,bey]1 & ,mr4 ,c4 ,m4 ,hebb]t t *apt]s ,,vi to ,,xi h be5 includ$4 ,ackn[l$gm5t & full cr$it is due !m z co-au?ors4 ,*ap4 ,,vi1 ,,vii1 & "p ( ,*ap4 ,,xi 7 prep>$ by ,pr(4 ,e4 ,a4 ,holbrook2 ,*ap4 ,,ix1 ,x1 pages #aeb-aeg ( ,*ap4 ,,viii1 & pages #agc-agg ( ,*ap4 ,,xi 7 prep>$ by ,mr4 ,o4 ,s4 ,bey]2 ,*ap4 ,,viii1 pages #acc-aeb1 0 prep>$ by ,mr4 ,c4 ,m4 ,hebb]t4 ,9 ! ,*apt] on 8,hi/ory ( ,aviation0 only ^? exp]im5ts are treat$ :i* h a be>+ on flight today2 ?is *apt] is to be us$ 9 conjunction ) ! ,*apt] on 8,pr9ciples ( ,flight10 especially z reg>ds controll+ ! airplane4 ,! "q ( ,airplane ,motors has n be5 t\*$1 because to d x ju/ice w\ld unduly increase ! size ( ?is volume1 & because adequate treatises on ! subject are available4 ,dec4 #ab?1 #aiag4 ,,cont5ts ,,page ,,preface vii ,,*apt] ,i4 ,hi/ory ( ,aviation #a ,,ii4 ,types ( ,milit>y ,airplanes & ,uses #ah ,,iii4 ,pr9ciples ( ,flight #ci ,,iv4 ,fly+ ! ,airplane #hj ,v4 ,cross-c\ntry ,fly+ #hi ,,vi4 ,! ,rigg+ ( ,airplanes--,nom5clature #aac ,,vii4 ,mat]ials ( ,con/ruction #abj ,,viii4 ,erect+ ,airplanes #acc ,,ix4 ,tru+ up ! ,fuselage #aeh ,x4 ,h&l+ ( ,airplanes 9 ! ,field & at ! ,bases ,previ\s to & ,aft] ,flights #aff ,,xi4 ,inspection ( ,airplanes #agc ,,le>n+ ,,to ,,fly ,,9 ,,! ,u4 ,s4 ,,army ,a ,,manual ,,( ,,aviation ,,practice ,,*apt] ,i ,,hi/ory ,,( ,,aviation ,t "p ( ! hi/ory ( ,aviation :i* has especial int]e/ = aviators is ( rec5t date1 & ext5ds back only two doz5 ye>s4 ,( c\rse ef=ts h be5 made t[>d manflight ev] s9ce ! e>ly sixte5? c5tury1 :5 ,leon>do da ,v9ci inv5t$ ! p>a*ute & became ! fir/ patron ( a]onautics2 betwe5 ! "t ( ?is fam\s arti/ & ! pres5t _m exp]im5t]s h giv5 _! att5tion to ! problem1 b previ\s to ! la/ decade ( ! n9ete5? c5tury no?+ practical 0 a*iev$4 ,!n1 ) ! p]fection ( ! /eam eng9e & ! developm5t ( ! gasol9e eng9e1 !re came inducem5t to s\nd exp]im5tation1 br++ =? su* well-kn[n figures z ,maxim1 ,langley1 ,lilli5?al & ,*anute4 ,! "w ( ea* ( ^! m5 is an int]e/+ /ory by itself1 especially t ( ,langley1 :o approa*$ ! matt] f a /rictly sci5tific viewpo9t1 e/abli%$ te/+ app>atus & built successful self-propell$ /eam models ye>s be=e ! ,wright bro!rs report$ _! indep5d5t successes4 ,he reproduc$ 8 models to full scale ) e expectation ( success1 b fail$1 due to exhau/ion ( 8 capital4 ,langley's ,exp]im5ts 9 ,a]ial ,navigation4--,9 all ! hi/ory ( a]ial navigation "o ( ! mo/ romantic /ories is t describ+ ! sci5tific rese>*es begun 9 #ahhg by ,langley & culm9at+ 9 #ahif 9 ! fir/ really successful case ( me*anical flight us+ a prime mov]2 cont9u+ up to #aijc :5 ?is fir/ successful ma*9e1 a model ( #ab-;ft4 span1 0 reproduc$ to full scale & mann$ = its trial flight by a human pilot2 & end+ ) ! de/ruction ( ?is full-siz$ ma*9e on laun*+1 s t ,langley miss$ ! glory ( be+ ! actual discov]] ( manflight only by a hair's bread?1 dy+ %ortly aft]w>d ( a brok5 he>t1 z is conc$$ by ^? :o knew him4 ,if ?is full-scale ma*9e _h p]=m$ z successfully 9 #aijc z x actually did aft] be+ rebuilt & p>tly remodell$ a decade lat] by ! ,curtiss company1 ,langley w\ld h ant$at$ ! fir/ successful flight made by ! ,wright bro!rs by a n>r[ m>g9 ( ab\t #b mon?s4 ,illu/ration3 7,c\rtesy ,s4 ,s4 ,mc,clure ,co47 ,,fig4 #a4--,! ,langley /eam model fly+ ma*9e4 ,x flew a mile 9 #ahif1 ! fir/ successful airplane to fly ) a prime mov]4 ,lilli5?al 7,g]many1 #ahid74--;,b omitt+ details reg>d+ ! e>ly exp]im5t]s we w consid] only t "p ( ! hi/ory ( aviation mo/ important to ! prospective aviator4 ,we w conf9e ourselves to ! sequ5ce ( glid+ & p[] exp]im5ts begun by ,lilli5?al1 c>ri$ =w>d by ,*anute & br\ght to completion by ! ,wrights4 ,illu/ration3 7,c\rtesy ,jas4 ,means' 8,a]onautical ,annual407 ,,fig4 #b4--,lilli5?al's biplane glid] 9 flight1 #ahid4 ,note4--7a7 ,ar*$ w+s2 7b7 fix$ tail2 7c7 me?od ( balanc+ by sw++ legs4 ,illu/ration3 7,c\rtesy ,jas4 ,means' 8,a]onautical ,annual407 ,,fig4 #c4--;,*anute's biplane glid]1 #ahif4 ,note improvem5t 9 rigidity by bridge-type truss+4 ,lilli5?al 0 ! fir/ man to accompli% successful flights ?r\gh ! air by ! use ( artificial w+ surfaces4 ,aft] _m ye>s ( exp]im5t & /udy ( so>+ birds he con/ruct$ rigid w+s :i* he held to 8 %\ld]s & :i*1 aft] he _h ga9$ consid]able velocity by runn+ =w>d d[nhill1 w\ld cat* ! air & lift 8 weight completely (f ! gr\nd4 ,! w+s 7 ar*$1 = he obs]v$ ?is 0 ! case 9 all birds2 flat w+s prov$ useless 9 flight1 & sugge/$ a reason = ! failure ( previ\s exp]im5t]s4 ,to ^! rigid w+s ,lilli5?al fa/5$ a rigid tail2 ! w+s & ! tail compris$ 8 8glid]40 ,!re 7 no control lev]s & ! only way ! op]ator c\ld /e] 0 to %ift ! balance by sw++ 8 legs "o way or ! o!r4 ,lilli5?al con/ruct$ an artificial hill = 8 glid+ s t he c\ld coa/ d[nw>d = "s di/ance )\t /rik+ ! gr\nd & he 0 able to accompli% _m glides ( a c\ple ( hundr$ y>ds 9 l5g?4 ,*anute 7,*icago1 #ahif74--;,*anute's exp]im5ts 9 glid+ 7 q simil> to ,lilli5?al's & 7 made on ! s& dunes along ,lake ,mi*igan outside ( ,*icago4 ,8 app>atus 0 m /rongly con/ruct$1 be+ ( truss$ biplane type1 a con/ruction sugge/$ to him by 8 exp]i5ce 9 bridge build+1 & "o :i* p]si/s today z ! basis ( /r5g? 9 our pres5t milit>y biplanes4 ,! ,wright ,bro!rs1 #aija4--,lilli5?al 0 kill$ 9 a glide1 hav+ lo/ control ( 8 app>atus :ile "s di/ance above ! gr\nd4 ,! ,wright bro!rs read ( 8 dea? & comm5c$ ?9k+ ov] ! :ole problem4 ,lilli5?al's me?od ( balanc+ 8 l>ge app>atus by ! m]e effect ( sw++ 8 legs appe>$ to !m z a v inadequate means ( control4 ,!y came to ! conclusion t ! imm$iate problem 9 artificial flight 0 ! problem ( /ability1 :i* !y felt %\ld be solv$ by an entirely diff]5t means ?an t employ$ by ,lilli5?al & ,*anute4 ,! "w already done _h demon/rat$ )\t "q t support 9 ! air _h be5 e/abli%$2 ) ! addition ( controllability ! ,wrights look$ =w>d to do+ some?+ wor? :ile 9 ! way ( artificial flight4 ,to improve ,lilli5?al's me?od ( %ift+ ! weight1 !y conceiv$ ! idea ( leav+ ! pilot 9 an immovable position 9 ! glid]1 & in/ead ( oblig+ him to %ift 8 weight ?is way & t1 !y propos$ to manipulate ! surfaces ( ! w+s !mselves by means ( lev]s "u ! pilot's control1 s t ! same result ( balanc+ c\ld be obta9$ by q a diff]5t & sup]ior me?od4 ,!y set out1 !re=e1 delib]ately to solve ! :ole "q ( airplane /ability4 ,!re 0 ! =e & aft or horizontal /ability1 = :i* ,lilli5?al _h swung 8 legs =w>d & backw>d2 !re 0 9 addition ! sidewise or lat]al /ability = :i* ,lilli5?al _h swung 8 legs to left & "r4 ,! fundam5tal requirem5ts to be met 7 t dur+ flight ! glid] %\ld be kept 9 its prop] attitude )\t div+ or re>+ up1 & )\t roll+ into an attitude :]e "o w+ tip 0 high] ?an ! o!r1 i4e41 ! ma*9e 0 to be kept level 9 bo? directions4 ,illu/ration3 ,fir/ ,wright glid]4 ,) front elevator1 %[n fly+ empty z a kite4 ,f9al ,wright glid]4 ,) rudd] & elevator4 ,note "r w+ w>p$ d[nw>d to raise "r w+ tip4 ,a successful d[nhill glide4 ,pilot lies prone on bottom w+4 ,,fig4 #d4 ,=e & ,aft ,control4--,aft] "s prelim9>y trials ! ,wrights f\nd t ! =e & aft balance c\ld be controll$ by an elevator or horizontal rudd]1 support$ on outrigg]s on ! front ( ! airplane1 & op]at$ by a lev]4 ,if ! pilot f\nd ! glid] pit*+ too mu* d[nw>d1 & t5d+ t[>d a dive1 he w\ld tilt ! elevator upw>d by mov+ ! lev]1 ?us turn+ ! glid] back into its prop] attitude4 ,?is elevator 9 mod]n ma*9es is back ( ! airplane1 a bett] place = x ?an 0 *os5 by ! ,wrights4 ,x may be said t _! *ief reason = fir/ putt+ x 9 front 0 t !y c\ld see x !re & obs]ve its effect4 ,!y soon realiz$ t ! re> location gave easi] control1 & !y act$ accord+ly4 ,lat]al ,control4--,aft] satisfy+ !mselves reg>d+ =e & aft control1 ! ,wrights took up lat]al control4 ,_! problem 0 to devise a means = keep+ ! span ( ! w+s level s t :5 = any reason "o w+ tip %\ld s9k l[] ?an ! o!r1 x c\ld be at once rais$ back to its prop] position4 ,lilli5?al _h tri$ to d ?is by sw++ 8 legs t[>d ! high side2 ! %ift$ weight re/or+ ! position4 ,! ,wrights1 to obviate ?is inadequate me?od1 be?\ght !mselves to re/ore equilibrium by means ( ! w9d itself r ?an by gravity4 ,!y obs]v$ an int]e/+ maneuv] employ$ by a pigeon :i* seem$ to secure its lat]al balance 9 exactly ! way !y want$2 ?is bird 0 se5 to give its two w+s ea* a diff]5t angle ( attack1 :]eat "o w+ w\ld lift m =cibly ?an ! o!r1 !reby rotat+ ! bird bodily 9 any desir$ am\nt or direction ab\t ! l9e ( flight z an axis4 ,to copy ?is bird app>atus 9 a ,wright glid]1 x 0 f\nd suffici5t to alt] ! angle ( ! w+ tips only1 leav+ ! *ief "p ( ! support+ surface 9 its orig9al rigid position4 ,9 o!r words1 ! w+ tips 7 to be w>p$2 ! "o to pres5t great] angle ( attack1 ! o!r less angle1 exactly z 9 ! case ( ! pigeon4 ,suppose ! airplane to develop a li/ to ! left1 ! w+ on t side s9k+1 ! pilot 0 to increase ! angle at ! tip ( ?is left-h& w+ by mov+ ! w>p+ lev]1 & at ! same "t decrease ! angle ( ! "r-h& w+ by ! same lev]4 ,he 0 to hold ?is position until ! airplane 0 right$ & br\ght back to level position4 ,?is arrangem5t prov$ to h ! effect anticipat$ & ma9ta9$ /ability easily on a glid] mu* l>g] ?an ,lilli5?al ev] manag$ ) 8 leg-sw++ me?od4 ,directional ,control4--,we h n[ foll[$ ! developm5t by ! ,wrights ( airplane control z reg>ds3 #a4 ,=e & aft or 8pit*+0 motion1 accompli%$ by an elevator op]at$ by lev]4 #b4 ,lat]al or 8roll+0 motion accompli%$ by w+ w>p+ op]at$ by a second lev]4 ,^! 7 ! only controls us$ 9 ! e>lie/ glid]s4 ,x rema9s to consid] ! ?ird elem5t ( control1 viz3 #c4 ,! directional or 8yaw+0 control1 :i* is accompli%$ by an ord9>y v]tical rudd] op]at$ by a ?ird lev]4 ,! ,wrights f\nd ! w>p+ _h all ! effect anticipat$ b _h also c]ta9 second>y & undesirable effects4 ,:5ev] !y appli$ ! w>p+ lev] to correct ! roll+ motion1 ! glid] respond$ z f> z roll+ control 0 conc]n$1 b at ! same "t w\ld 8yaw0 or sw]ve out ( its c\rse to "r or left4 ,?is 0 a s]i\s complication4 ,=1 9 ! mom5t ( sw]v+1 ! high w+ :i* !y desir$ to depress w\ld advance fa/] ?an ! l[ w+1 & solely by its high] velocity t5d$ to develop a great] lift & !reby neutralize ! b5eficial effect ( ! w>p4 ,9 _m ( _! e>ly glides1 because ( pron\nc$ sw]v+1 ! w>p effect 0 entirely c\nt]act$ & fail$ to br+ ! glid] back to level2 ) ! result t "o w+ tip w\ld s9k1 at ! same "t sw++ backw>d until ! ma*9e 0 br\ght to ! gr\nd4 ,no am\nt ( controll+ c\ld prev5t ?is4 ,aft] mu* bewild]m5t on ?is po9t1 ! ,wrights obs]v$ t :5ev] a w+ tip 0 w>p$ to a l>ge angle its resi/ance became relatively great] & x sl[$ up :ile ! opposite side w5t ahead4 ,!y at once hit ^u ! idea ( a rudd]1 previ\sly consid]$ unnecess>y1 :i* !y believ$ c\ld be turn$ 9 ea* case ( yaw+ j en\gh to create a new & appos+ yaw+ =ce ( equal magnitude4 ,!y !re=e atta*$ a rudd] at ! re>1 connect+ its till] ropes to lev] ,no4 #b1 & giv+ ?is lev] a comp\nd motion s t "o h& c\ld op]ate ei!r w>p or rudd] control indep5d5tly 7or simultane\sly 9 prop] proportion to elim9ate ! yaw+ t5d5cy above m5tion$74 ,?is comb9ation is ! basis ( ! ,wright pat5ts & is ess5tial 9 airplanes ( today4 ,great success n[ ensu$ 9 _! glid+ exp]im5ts2 ! ma*9e 0 always 9 p]fect control2 c\ld be manipulat$ 9 any desir$ mann]2 turn$ to "r or left1 or br\ght d[n to e>? ) safety4 ,?us 7 ! ?ree elem5ts ( control appli$ by ! ,wrights to _! glid] & ! problem app>5t 9 ,lilli5?al's dea? 0 solv$4 ,! next /ep 0 to in/all a p[] plant able to ma9ta9 =w>d spe$ )\t resort+ to coa/+ d[nhill by gravity2 & !re=e capable ( produc+ a horizontal flight4 ,9 develop+ a p[] fly] aside f ! "q ( control ! prop] design 0 arriv$ at z foll[s3 ,effici5cy ( ,w+s4--,! ,wrights knew f ,langley & ,*anute t flat w+s 7 ineffici5t & useless1 & curv$ w+s ess5tial2 !y did n "k :e!r ! am\nt ( curvature matt]$ mu*4 ,to f9d ?is out by trials 9 glid+ w\ld be sl[ & exp5sive4 ,!y adopt$ a bett] way--! w9d-tunnel me?od1 :]e9 small-scale models 7 te/$ & comp>$ = effici5cy 9 a bla/ ( air4 ,!y made _! w9d tunnel #af 94 9 diamet] & creat$ a p[]ful air bla/ ?r\gh x by means ( an eng9e-driv5 fan4 ,small models ( w+s 7 plac$ 9 ! c5t] ( ?is conf9$ air bla/1 m\nt$ on a balance arm :i* project$ into ! tunnel f ! outside4 ,! air =ces & effici5cy ( ! models 7 ?us measur$4 ,a l>ge v>iety ( %apes 7 te/$ & "o 0 select$ z be/ ( all f ! /&po9t ( curvature & r\nd$ w+ tips4 ,?is %ape 0 adopt$ 9 _! fly]1 & ?\gh on a mu* l>g] scale fulfill$ ! pr$ictions made = its effici5cy 9 ! indoor w9d-tunnel exp]im5ts4 ,! ,wright glid] 01 ( c\rse1 a biplane model4 ,!y te/$ a small #f-;94 model biplane & f\nd t ! two w+s toge!r 7 less effici5t ?an ei!r w+ by itself4 ,h[ev]1 o!r consid]ations1 su* z rigidity ( truss+1 decid$ !m to adopt ! biplane r ?an a monoplane arrangem5t4 ,l[ ,resi/ance to ,=w>d ,motion4--,! ,wrights us$ _! w9d tunnel also 9 *oos+ = ! /ruts ( _! airplane a %ape :i* w\ld pres5t lea/ head resi/ance to =w>d motion4 ,!y f\nd t a squ>e /rut _h a resi/ance :i* c\ld be decreas$ by *ang+ ! %ape to resemble a fi%4 ,! resi/ance ( ! pilot himself 0 decreas$ by mak+ him lie prone1 face d[nw>d on ! bottom w+4 ,propell] ,effici5cy4--,al?\gh little data on ! subject ( propell] effici5cy 0 available to ! ,wrights1 !y 7 able to arrive at a v cr$itable design :]e9 two propell]s 7 us$1 driv5 f a s+le motor1 & rotat+ "o ea* side ( ! pilot4 ,! me*anical difficulties :i* h s9ce emb>rass$ ! use ( two propell]s 7 less ) ! ,wrights because !y 7 deal+ ) small] horsep[]s ?an are 9 use today2 !y !re=e 7 able to realize a v high propell] effici5cy4 ,motor4--,:5 ! ,wrights 7 ready to apply a motor to _! glid]1 !y f\nd x impossible to secure "o light en\gh1 & _h to set ab\t build+ "o !mselves4 ,!y adopt$ a f\r-cyl9d] type1 wat]-cool$1 & _! aim 0 to save weight & complication :]ev] possible4 ,_! fir/ motor gave ab\t #ab hp41 :i* 0 rais$ to a high] & high] figure by subsequ5t improvem5ts until x rea*$ #bj hp4 ,9 its e>lie/ /ages x 0 able to give suffici5t p[] = %ort horizontal flights4 ,means ( ,/>t+ & ,l&+4--,"o reason ! ,wrights c\ld use su* l[ horsep[] 0 t !y employ$ auxili>y />t+ app>atus to get up orig9al spe$4 ,!y knew t less horsep[] 0 necess>y to fly an airplane aft] x 0 once 9 ! air ?an 0 necess>y to get x into ! air at ! />t1 & !y !re=e rigg$ up a catapult :i* project$ _! airplane =w>d on a roll+ c>riage ) great =ce at ! />t1 s t all ! motor _h to d 0 to ma9ta9 ! flight 9 air4 ,! ,wright airplane _h at fir/ no l&+ :eels1 & 0 provid$ only ) light skids on :i* x c\ld make a dec5t l&+4 ,pres5t-day airplanes1 ( c\rse1 h :eels on :i* to roll bo? at />t+ & at l&+ & _! motors are p[]ful en\gh to elim9ate ! necessity = a />t+ catapult4 ,illu/ration3 7,c\rtesy ,am]ican ,te*nical ,society & ,sci5tific ,am]ican ,supplem5t47 ,,fig4 #e4--;,details ( ,bl]iot ,,xi monoplane4 ,bl]iot's ,contribution to ,aviation4--,bl]iot exp]im5t$ a great _m ye>s be=e he atta9$ success & did s ye>s aft] ! ,wrights _h successfully fl[n4 ,b :5 he did obta9 success1 8 great +5uity produc$ features ( design :i* 7 a decid$ /ep =w>d4 ,he add$ a body to ! airplane & produc$ a ma*9e :i* in/ead ( be+ a pair ( w+s ) v>i\s app5dages1 0 a body to :i* w+s 7 atta*$1 giv+ a m %ip%ape & conv5i5t arrangem5t4 ,! motor1 in/ead ( be+ locat$ beside ! pilot z 9 ! ,wright ma*9e1 0 put 9 ! v front ( ! body ahead ( ! pilot :]e x 0 n likely to fall on him 9 case ( a sma%4 ,?is location ( ! motor entail$ ! use ( a s+le propell] at ! front1 a 8tractor0 screw z x 0 call$1 less effici5t ?an ! d\ble propell] ( ! ,wrights1 b bett] f ! /&po9t ( me*anical conv5i5ce4 ,! body ( a ,bl]iot1 :i* 0 q simil> to ! body ( any bird 9 its g5]al arrangem5t1 project$ to ! re> 9 a tap]+ =m & c>ri$ at ! re> a rudd] & elevator4 ,! motor1 pilot & tanks 7 ?us enclos$ )9 ! body & away f ! w9d4 ,bl]iot's contributions 7 !n1 bett] location ( ! motor1 adaptation ( ! body or 8fuselage10 elim9ation ( ! front elevator & sub/itution ( ! re> elevator4 ,nieuport & ,fokk]'s ,contribution to ,aviation4--,a fur!r advance on ,bl]iot's design 0 made by ,nieuport & lat] by ,fokk]4 ,! =m] utiliz$ ! fuselage pr9ciple ( ,bl]iot & enclos$ ! :ole framework1 front & back1 to give a /ream-l9e =m1 & ev5 w5t s f> z to make w9d-tunnel exp]im5ts f :i* he 0 able to *oose a v effici5t fuselage %ape z well z w+ & /rut effici5cy4 ,illu/ration3 7,f ,hayw>d's 8,practical ,a]onautics407 ,,fig4 #f4--,nieuport monoplane4 ,repres5t+ an advance 9 spe$1 due to cov]$ /ream-l9e body4 ,,*apt] ,,ii ,,types ,,( ,,milit>y ,,airplanes ,,& ,,_! ,,uses ,mod]n ,airplanes ,comb9+ ,be/ ,features ( ,previ\s ,exp]im5ts4--,! mod]n airplane1 ( :i* ! ,curtiss tra9+ ma*9e us$ at ! ,u4 ,s4 ,aviation ,s*ools is typical1 is a comb9ation ( ! be/ features ref]r$ to above4 ,x is ( ! biplane type =1 z %[n by ,*anute1 rigid truss+ is ?us possible1 an advantage suffici5t to (fset ! slight loss ( effici5cy :i* exi/s 9 ! biplane4 ,! l&+ ge> consi/s ( two :eels provid$ ) %ock absorb]s2 ! body is ( ! g5]al /ream-l9e type1 enclos$ f front to back1 conta9+ com=table seats = ! pass5g]s & enclos+ ! motor & tanks away f ! w9d4 ,! motor is at ! front :]e1 9 an accid5t1 x w n be on top ( ! pilot4 ,! w>p+ effect is obta9$ by h++ flaps at ! w+ tips1 ! same effect be+ obta9$ :ile at ! same "t leav+ ! :ole w+ /ructure rigid & /rong r ?an flexible & weak1 z 0 ! case 9 ! e>ly w>p+ type ( ma*9es4 ,milit>y ,airplanes ( ,today4--,9 ! mod]n airplane1 !re=e1 we see t matt]s ( effici5cy1 to :i* ! ,wrights gave great att5tion1 h be5 sacrific$ 9 favor ( conv5i5ce1 p>ticul>ly 9 favor ( p[] & spe$4 ,?is is ! effect ( milit>y dem&s = airplanes :]e p[]1 spe$1 & ability to climb fa/ are vital requirem5ts4 ,to escape f or to de/roy an enemy1 high spe$ & ability to climb fa/ are1 ( c\rse1 pr]equisites4 ,moreov]1 f ! /&po9t ( safety 9 maneuv]+ x is desirable to h a res]ve ( p[] & spe$4 ,!re=e1 ! design ( milit>y ma*9es has t5d$ 9 a giv5 direction up to ! pres5t4 ,new consid]ations h aris5 on ?is acc\nt1 su* z = in/ance ! "q ( l&+4 ,fa/ ma*9es 9 g5]al make high-spe$ l&+s1 & are = t reason dang]\s4 ,! orig9al ,wright ma*9es 7 built to l& at su* a sl[ spe$ t ord9>y skids 7 suffici5t to take ! %ocks4 ,n[adays ! high-p[]$ airplane is likely to come to grief 9 l&+ m ?an at any o!r "t4 ,! "q ( /ability 9 flight has ( rec5t ye>s be5 treat$ ma!matically & exp]im5tally1 us+ ( c\rse ! fundam5tal sy/em ( 8?ree axes control0 fir/ appli$ by ! ,wrights4 ,x has be5 f\nd t by prop]ly proportion+ ! tail surfaces & prop]ly arrang+ ! w+s & c5t] ( gravity1 any desir$ degree ( /ability may be obta9$1 su* t a ma*9e may be made almo/ self-fly+ or1 if pref]r$1 may be made v s5sitive4 ,all ( ! above features ( design h _h consid]ation 9 ! late/ types ( milit>y airplanes4 ,obs]ve ! high spe$ ( ! late/ spe$ sc\ts1 :]e p[] is conc5trat$ exclusively on spe$ & climb+ ability & l&+ spe$ is dang]\sly high4 ,we see ! adv5t ( ! triplane sc\t1 :i* is an attempt to secure sl[ l&+ spe$ comb9$ ) high fly+ spe$4 ,we see ma*9es ) ! motor & propell] 9 ! re>1 or ) two motors1 "o to ea* side ( ! body out 9 ! w+s1 ! object be+ to avoid int]f]5ce ( ! propell] ) ! range ( gun fire4 ,9 %ort1 we see ! effect ( _m milit>y consid]ations on ! design ( ! airplane4 ,x w be int]e/+ at ?is po9t to survey :at are ^! milit>y uses ( ! airplane4 ,a]ial ,fight+4--,fight+ 9 ! air is ! mo/ spectacul> use to :i* milit>y airplanes h be5 put4 ,! fir/ requirem5ts 9 a fight+ airplane are spe$ & climb+ ability & ^! mu/ be obta9$ at all co/s1 because spe$ & climb are weapons ( def5se & (f5se second only 9 value to ! gun itself4 ,! conc5tration ( motive p[] = spe$ & climb requires t z little weight z possible be us$2 & !re=e ! fa/e/ fight]s are design$ to c>ry only "o p]son & are v light & ( c\rse v small4 ,x is usual to h "o gun fix$ to ! body & fir+ ?r\gh ! propell] 9 ! case ( a tractor1 & a second adju/able aim gun po9t+ upw>ds ov] ! top w+4 ,?is gives ! pilot a *ance to fire a r\nd at ! enemy :ile 8sitt+ on 8 tail0 or foll[+ f beh9d2 & !n :5 div+ bel[ ! enemy ! second gun is available = %oot+ ov]head4 ,^! v high-spe$ fight]s are difficult to l&1 due to _! spe$1 & are suitable only = ! highe/-tra9$ pilots4 ,direct+ ,artill]y ,fire4--,! fri5dly airplane is s5t out ov] ! enemy's positions1 so>s above ! t>get1 s5ds back signals by wireless to ! fri5dly batt]y reg>d+ ! effect ( fire2 practically dictat+ ! success ( artill]y op]ations4 ,reconnaissance4--,! fri5dly airplanes g out1 usually 9 squads = ! sake ( protection1 & obs]ve by means ( photographs or vision size ( enemy troops1 batt]ies1 tr5*es1 l9es ( communication1 etc42 report ! situation to headqu>t]s z a s\rce ( daily photographic record ( ! op]ations ( ! enemy1 to su* an ext5t t any *ange ( ! enemy's position c be analyz$4 ,( c\rse ! value ( reconnaissance is less5$ :5 ! enemy disguises 8 gun emplacem5ts1 etc4 ,9 reconnaissance ma*9es x is important to h two p]sons1 "o to /e] & ! o!r to scan ! c\ntryside4 ,! reconnaissance ma*9e is !re=e a two-place type :i* may or may n h armam5t4 ,x ne$ n be s fa/1 especially :5 convoy$ by fight+ spe$ sc\ts4 ,! two-place ma*9es are frequ5tly us$ = fight+1 9 :i* case ! pilot w h a gun fix$ to ! body & %oot+ ?r\gh ! propell]1 & ! pass5g]1 especially 9 ,g]man ma*9es1 w also h a gun m\nt$ 9 ! turret s t x may be %ot 9 a v>iety ( directions by ! pass5g]4 ,bomb ,dropp+4--,?is maneuv] requires squad flights to be ( great value4 ,! fundam5tal *>act]i/ic ( a bomb+ airplane is its ability to c>ry great weight4 ,su* ma*9es are ( comp>atively l>ge size & n p>ticul>ly fa/4 ,weight c>ry+ is ( c\rse incompatible ) spe$ & climb+ ability & !re=e ! bomb+ ma*9e mu/ be a compromise if x is to h any reasonable spe$4 ,x may be said t airplanes comp>e v unfavorably ) dirigible balloons = bomb raids because ! latt] are able to c>ry sev]al tons ( bombs z aga9/ ! airplane's qu>t] ( a ton4 ,locat+ ,subm>9es4--,= coa/ patrol or subm>9e spott+1 ! airplane is an important factor1 = f an airplane x is possible to see = a consid]able dep? into ! wat]1 & to locate ho/ile subm>9es4 ,tra9+ ,/ud5t ,aviators4--,! tra9+ ma*9e on :i* prospective aviators secure _! fly+ in/ruction may be consid]$ z a type 9 :i* great spe$ & p[] is n ess5tial1 b 9 :i* reliability & ease ( control is desirable4 ,! typical milit>y tra9+ airplane 9 ?is c\ntry is a s+le-motor tractor ( mod]ate horsep[] 7ab\t #ajj7 hav+ ( c\rse ! seats 9 t&em & furni%$ ) dual control s t op]ation may be f ei!r pilot's or pass5g]'s seat4 ,! dual-control sy/em ( tra9+ :i* prevails 9 ?is c\ntry diff]s f ! ,fr5* me?od ( />t+ ! pupil out alone to try 8 w+s2 x enables ! pilot to keep a con/ant eye ^u ! pupil's control manipulations & to correct !m in/antly :5ev] !y are 9 error be=e any damage is done4 ,a possible improvem5t 9 ! dual-control tra9+ ma*9e w be ! sub/itution ( side by side seats = t&em seats4 ,at pres5t1 communication is difficult due to ! great noise ( ! motor2 b ) ! adoption ( side by side seats su* z is us$ 9 naval tra9+ s*ools1 ! pilot & pupil w be able to communicate to bett] advantage4 ,illu/ration3 ,,fig4 #g4--,u4 ,s4 tra9+ airplane1 dual control 7,curtiss ,,jn-#d74 ,spe$ #dc to #gb mi4 p] hr42 climb+ ability #cjj ft4 p] m942 #ij h4p42 weight fully load$ #a1hij lbs4 ,types ( ,airplanes4--,to suit ! =ego+ purposes fly+ ma*9es exi/ 9 sev5 di/9ct diff]5t %apes at ! pres5t "t1 namely3 monoplanes1 biplanes1 triplanes1 s+le-motor tractors1 s+le-motor pu%]s1 d\ble-motor ma*9es & m>9e airplanes4 ,! la/ f\r types may be ei!r monoplanes1 biplanes or triplanes4 ,9 ord] to und]/& ! adoption ( "o or ! o!r type = milit>y use1 x is well to run ov] ! *>act]i/ics ( ! sev5 types m5tion$4 ,monoplanes4--,! simple/ =m ( airplane is ! monoplane :i* is fa%ion$ aft] ! mann] ( a bird 7see ,fig4 #cd74 ,!re are two ?+s to say 9 favor ( ! monoplane3 fir/1 t ! pass5g]s h an unob/ruct$ view =w>d & range ( gun fire upw>d because !re is no w+ above !m2 second1 ! a]odynamic effici5cy ( ! monoplane is sup]ior to any o!r type4 ,b :5 ! bird design is appli$ to a man-c>ry+ app>atus1 x becomes impracticable to con/ruct sp>s to take ! place ( ! bird's w+ bones2 & !re=e to give ! w+s prop] /r5g? x becomes necess>y to truss !m ) num]\s t5sion wires /ret*+ f ! runn+ ge> out to v>i\s portions ( ! w+s4 ,!re are also wires runn+ f a v]tical ma/ above ! body to a po9t on ! top "p ( ! w+2 ^! wires1 :ile !y give ! w+ no add$ /r5g? dur+ a flight1 are necess>y 9 ord] t ! %ock ( l&+ %all n break ! w+s (f %>p at ! %\ld]4 ,x is *>act]i/ic ( monoplane con/ruction t f a po9t bel[ ! body & also f a po9t above ! body a numb] ( heavy wires run outw>d to v>i\s po9ts on ! w+s2 & x may be said t ! /r5g? to be secur$ f ?is con/ruction is n all t c\ld be desir$4 ,biplanes4--,! biplane is an improvem5t ov] ! monoplane f ! latt] /&po9t2 9 ! biplane !re are two p>allel surfaces sep>at$ by v]tical /icks or /ruts1 ?us =m+ p>allelograms :i* are susceptible ( be+ truss$ by means ( t5sion-wire diagonals 9 a mann] famili> & well und]/ood 9 case ( bridges4 ,x is possible to build up biplane w+s ( great rigidity & /r5g? by ?is sy/em1 mu* m easily ?an 9 case ( monoplanes4 ,h[ev]1 ! biplane type is f ! /&po9t ( effici5cy inf]ior to ! monoplane4 ,?is is due to ! fact t ! vacuum above ! bottom w+ :i* is s necess>y = high duty is some:at int]f]$ ) by ! upp] w+2 ?us :ile 9 a biplane ! upp] w+ op]ates ab\t z effici5tly z x w\ld op]ate 9 a monoplane1 yet ! l[] w+ has its effici5cy mat]ially r$uc$ & ! result+ ov]all effici5cy ( a biplane comp>$ area = area ) ! monoplane is ab\t #he p] c5t4 z great4 ,h[ev]1 rec5t developm5ts ( ! airplane h m or less put effici5cy 9 ! backgr\nd & z a result today ! biplane is m popul> ?an ! monoplane4 ,9 addition to ! great] /r5g? ( biplane w+s _! span may be less ?an ! monoplane = ! same support+ area4 ,?is makes !m less unwieldy4 ,moreov]1 = c]ta9 reasons a biplane ma*9e ( high spe$ may be l&$ at a l[] spe$ ?an equival5t monoplanes4 ,triplanes4--,:at is true ( ! biplane is m true 9 almo/ e item ( ! triplane1 t is1 x is comp>atively /rong1 compact1 & ( l[ l&+ spe$1 b ( r$uc$ effici5cy4 ,illu/ration3 ,,fig4 #h4--,u4 ,s4 spe$ sc\t triplane1 s+le seat]4 7,curtiss ,model ,s#c71 #ee to #aae mi4 p] hr42 climb+ ability #ijj ft4 p] m942 #ajj h4p42 weight fully load$ #a1cbj lbs4 ,s+le-,motor ,tractors4--,! s+le-motor tractor receiv$ its "n simply because ! propell] is 9 front & draws ! ma*9e =w>d2 b ?is location ( ! propell] necessitates a di/9ct type ( airplane1 :]e9 ! p[] plant is locat$ at ! v nose ( ! ma*9e4 ,! tractor type has ! pilot & pass5g] locat$ 9 or to ! re> ( ! w+s 9 ord] t _! weight may balance ! weight ( ! motor4 ,?is means t ! view & range ( fire ( ! pass5g]s is ob/ruct$ 9 a =w>d direction by ! w+s1 & 9 ma*9es su* z ! ,u4 ,s4 tra9+ ma*9e1 ! pass5g]1 :o is practically 9 ! c5t] ( ! w+s1 c n look directly upw>d nor directly d[nw>d4 ,moreov]1 z conc]ns gun fire1 ! propell] ( a tractor ob/ructs ! range /raight ahead4 ,9 ! tractor ! tail is support$ at ! re> & on ! same body :i* conta9s ! motor & pass5g]s2 ?is body con/itutes a /ream-l9e h\s+ = ! ma*9]y1 seats1 etc41 & !re=e has l[ w9d resi/ance4 ,! tractor is a v %ip%ape design1 compact & simple & is at pres5t ! prevail+ type on ! ,european w> front4 ,h[ev]1 x has disadvantages :i* are only ov]come 9 o!r types4 ,"o ( ^! disadvantages is ( c\rse ! ob/ruction to range ( gun fire4 ,! pres5t practice 9 fight+ airplanes is simply to %oot ! gun /raight ?r\gh ! circle ( rotation ( ! propell] on ! assumption t mo/ ( ! bullets w get ?r\gh & t ^? :i* hit ! %ank ( ! propell] blade w be deflect$ by prop] armor+4 ,an attempt is made to insure t all ! %ots w get ?r\gh by connect+ ! gun me*anism me*anically to ! motor %aft 9 su* a way t bullets w be dis*>g$ only at ! in/ant :5 _! pa? is unob/ruct$ by a propell] blade4 ,?is practice is possible ( c\rse only 9 guns :i* are fix$ immovably to ! airplane4 ,illu/ration3 ,,fig4 #i4--;,fuselage diagram1 ,curtiss 8,r#d0 reconnaissance biplane4 ,spe$ #dh to #ij mi4 p] hr42 climb+ ability #djj ft4 p] m942 #bjj h4p42 weight fully load$ #c1bde lbs4 ,illu/ration3 ,,fig4 #aj4--;,an ,am]ican pu%] biplane design4 ,crew 9 front1 motor & propell] 9 ! re>1 tail support on outrigg]s4 ,s+le-motor ,pu%] ,airplanes4--,! pu%] type has popul>ity because ! propell] & motor rotate to ! re> ( ! pass5g]1 :o takes 8 place 9 ! v front ( ! body & has an op5 range ( vision & gun fire d[nw>d1 upw>d & sideways4 ,ano!r po9t 9 favor ( ! pu%] is t ! oil & fumes ( ! motor d n bl[ into 8 face z 9 ! case ( ! tractor4 ,! disadvantage ( ! pu%] is t ! motor1 be+ locat$ beh9d ! pilot1 w be on top ( him 9 ! case ( a fall4 ,ano!r disadvantage is t ! body c n be giv5 its %ip%ape /ream-l9e =m because to d s w int]f]e ) ! rotation ( ! propell]4 ,!re=e1 ! body is abruptly t]m9at$ j to ! re> ( ! w+s & x is j long en\gh to hold ! pass5g] & ! motor1 ! propell] /ick+ out beh9d4 ,! tail surfaces are !n atta*$ to ! airplane by means ( long outrigg]s spr++ f ! w+ beams at po9ts suffici5tly f> f ! propell] axis s z n to int]f]e ) ! propell]4 ,illu/ration3 ,,fig4 #aa4--,u4 ,s4 army battle plane4 ,two #ajj h4p4 motors2 spe$ #he mi4 p] hr4 ,d\ble-motor ,ma*9es4--,9 ord] to comb9e ! advantages ( ! tractor & pu%] types & elim9ate _! disadvantages1 ! d\ble-motor ma*9es h be5 develop$4 ,9 ^! !re is no ma*9]y :atev] 9 ! body ei!r 9 front or back1 & ! pass5g]s may take seats at ! extreme front z is desirable4 ,! body !n tap]s (f to ! re> 9 /ream-l9e =m & supports ! tail surfaces4 ,! p[] plants are 9 duplicate & "o is locat$ to ea* side ( ! body out on ! w+s4 ,x is cu/om>y to enclose ea* ( ^! two motors 9 a cas+ s t ! :ole p[] plant pres5ts a m or less /ream-l9e %ape to ! w9d1 ! propell]s project+ f ! front or re> ( ^! /ream-l9e %apes4 ,x may be said t 9 ! d\ble-motor airplane x makes v little diff]5ce :e!r ! propell] is 9 front or beh9d s t :ile a 8tw9-motor0 ma*9e may be m accurately specifi$ z a 8tw9-motor pu%]0 or a 8tw9-motor tractor10 x is usually suffici5t indication ( a ma*9e's *>act]i/ics to call x a tw9-motor ma*9e4 ,by adopt+ ?is tw9-motor =m we br+ 9 new disadvantages4 ,"o ( ^! is due to ! fact t ! heavy motors are n[ locat$ "s di/ance f ! c5t] ( gravity ( ! ma*9e4 ,?is requires /rong] support+ memb]s betwe5 ! motor & ! body4 ,x also makes ! lat]al control comp>atively logy = n[ ! heavy masses are f> f ! c5t] ( gravity1 resi/+ ! pilot's ef=ts to use ! lat]al control4 ,! second disadvantage 9 ! tw9-motor type results f possible /oppage ( ei!r motor4 ,9 ?is case1 ( c\rse1 ! propell+ =ce is "s di/ance (f c5t] & is also r$uc$ to "o-half its value requir+ en]getic ex]cise ( ! control :eel to ma9ta9 equilibrium4 ,x is report$1 h[ev]1 t tw9 ma*9es c cont9ue to fly & ev5 climb ) only "o motor runn+4 ,9 ?is c\ntry ! tw9-motor type has n develop$ z 0 hop$ at fir/1 & on ! ,european fir+ l9es x is n s num]\s z ! s+le-motor tractor type4 ,m>9e ,airplanes4--,! possibility ( me*anical flight hav+ once be5 e/abli%$ & :eels hav+ be5 appli$ to ! airplane s t x c\ld />t f & l& on ! gr\nd1 ! logical next /ep 0 to sub/itute "s =m ( boat = ! :eels s t flights c\ld be made ov] ! wat]4 ,exp]im5ts 7 made 9 ,france by ,m4 ,fabre 9 ?is direction & 9 ?is c\ntry by ,g4 ,h4 ,curtiss4 ,! latt]1 9 8 flight d[n ! ,hudson f ,albany to ,new ,york1 equipp$ 8 airplane ) a light float to provide aga9/ =c$ l&+ 9 ! riv]4 ,pursu+ ?is g5]al idea he made "s exp]im5ts "u ! auspices ( ,alex&] ,graham ,bell's ,a]ial ,exp]im5t ,association1 9 :i* a canoe 0 sub/itut$ = ! :eels1 & 9 :i* an attempt 0 made to />t f ! surface ( ! wat]4 ,success did n come at fir/ & ?is plan gave no satisfaction4 ,curtiss next turn$ 8 att5tion to ! hydroplane type ( boat & made a s]ies ( exp]im5ts at ,san ,diego4 ,! hydroplane appe>$ to be mu* bett] adapt$ to 8 purpose ?an ! canoe _h be51 & he 0 able to obta9 success4 ,illu/ration3 ,,fig4 #ab4--,?omas ,type ,h4 ,s4 seaplane4 ,d\ble pontoons4 ,spe$ #dg to #hb mi4 p] hr42 climb+ ability #bgj ft4 p] m942 #ace h4p42 weight1 fully load$ #b1fjj lbs4 ,illu/ration3 ,,fig4 #ac4--;,curtiss ,model ,f fly+ boat4 ,spe$ #de to #fe mi4 p] hr42 climb+ ability #aej ft4 p] m942 #ij h4p42 weight fully load$ #b1ajj lbs4 ,! ,hydro-airplane 7or 8,seaplane074--,f analogy to ! airplane "o might at fir/ imag9e t a suitable hydroplane w\ld h a wide span & =e & aft l5g?2 b su* proportion w\ld give a v poor /ability on ! wat]1 & w\ld require auxili>y hydroplanes 9 ! same way t an airplane requires auxili>y guid+ surfaces4 ,s ,curtiss1 ) 8 cu/om>y eye = simplicity & conv5i5ce1 adopt$ a type ( hydroplane :i* _h ! g5]al proportions ( an ord9>y boat1 i4e41 0 long & n>r[1 ?us obviat+ ! necessity ( auxili>y hydroplanes at ! tail ( ! ma*9e4 ,to prev5t ! ma*9e's tipp+ ov] sidewise1 8w+ pontoons0 7 atta*$ at ! l[] w+ tips to prev5t capsiz+4 ,illu/ration3 ,,fig4 #ad4--;,build+ a fly+ boat hull4 ,note w+ /umps & hydroplane f9s4 ,illu/ration3 ,,fig4 #ae4--,me?od ( hoi/+ a m>9e airplane abo>d %ip4 ,! ,fly+ ,boat4--,9 ! e>ly hydro-airplane1 :i* 0 ?us develop$1 ! motor & pilot 7 above 9 ! usual position 9 ! w+s1 :ile ! hydroplane itself 0 a consid]able di/ance bel[ ! w+s4 ,?us !re 0 a good deal ( head resi/ance4 ,curtiss set ab\t r$uc+ ?is head resi/ance z f> z possible & tri$ to incorporate ! pilot's seat ) ! hydroplane pontoon4 ,! outcome ( 8 endeavor 0 t he develop$ a boat ) a tap]+ /]n4 ,! pilot1 gasol9e tanks1 etc41 are locat$ inside ( ! hull2 ! tap]+ /]n provides a backbone to :i* ! tail surfaces c be readily atta*$2 ! w+s fix$ to ! sides ( ! hull 9 a mann] analog\s to ! w+ fa/5+s ( ! mod]n milit>y airplane2 & ! motor alone rema9s expos$ to ! w9d4 ,?is is ! fly+ boat2 its action on ! wat] is analog\s to ! action ( ! hydroplane = ! bottom ( ?is boat hull is made 9 hydroplane =m2 inde$1 9 ! late/ types ( fly+ boat1 ! hydroplane area is increas$ by ext5d+ x to "r & left ( ! boat hull4 ,! fly+ boat is an +5i\s comb9ation1 :]e9 ! *>act]i/ics ( ! hydroplane are comb9$ ) ! seawor?9ess ( ! ord9>y boat1 & at ! same "t w9d resi/ance is r$uc$ to a m9imum4 ,! hydro-airplane rema9s 9 use1 h[ev]1 be+ pref]able to ! fly+ boat = c]ta9 purposes1 & (t5 is t]m$ seaplane4 ,future ( ! ,airplane4--,9 ord] to be comm]cially successful & h a comm]cial future aft] ! w>1 ! foll[+ weak po9ts 9 airplane design mu/ be rectifi$4 #a4 ,motor4--,airplane motors are imp]fect & unreliable at pres5t & !re mu/ be consid]able progress be=e ?is type ( motor :i* is v light & delicate c be consid]$ z reliable or c be made 9 l>ge en\gh quantities to cut d[n ! co/4 #b4 ,l&+4--,! necessity ( l&+ at consid]able spe$1 say #dj to #ej miles p] h\r1 requires a wide flat space1 su* z is n easy to f9d1 & if ! pres5t type ( airplane is to become comm]cially num]\s1 a l>ge numb] ( l&+ fields mu/ be develop$ all ov] ! c\ntry4 #c4 ,dang]4--,! airplane is by no means s dang]\s z ! public has be5 l$ to ?9k f ! exploits ( ! d>$evil circus p]=m]s ( ! pa/ #aj ye>s2 ) c>eful manipulation x w make trips day aft] day )\t any damage4 ,h[ev]1 x is n a foolpro( ma*9e & !re rema9s an elem5t ( dang] on ?is acc\nt1 :i* x is hop$ w "o day be elim9at$4 ,future ,uses ( ! ,airplane4--,future uses ( ! airplane are _m aft] ! w> is ov]4 ,! po/al s]vice ( sev]al gov]nm5ts are consid]+ ?is means ( mail deliv]y2 ! sports use z 9 ! pa/ w cont9ue to fl\ri%2 express c>ry+ may be expect$ 9 inaccessible c\ntries :]e railroads & roads d n give access & :]e high-spe$ deliv]y by c\ntless airplanes w\ld aid mat]ially 9 ! developm5t ( newly op5$ c\ntries4 ,= airplane transportation w require no exp5sive "r-(-way1 rubb]-tire r5ewals1 etc4 ,m9or uses ( airplanes are on su* duties z =e/-fire patrol1 work+ at life-sav+ /ations1 etc4 ,am]ican ,airplane ,indu/ries4--,! magnitude ( ! airplane indu/ry 9 ?is c\ntry is great1 al?\gh n s great z 9 ,europe4 ,lead+ bus9ess m5 h inve/$ 9 ?is indu/ry ) ! firm belief t x w become a pr(itable "o1 irrespective ( w>4 ,we see a numb] ( lead+ bank]s & also automobile manufactur]s 9 v>i\s p>ts ( ! c\ntry putt+ _! money into ?is new indu/ry4 ,n[ t a great dem& has sprung up on our side ( ! wat] = airplanes1 we w expect to see ?is indu/ry increase m rapidly /ill4 ,! only result c be1 f all ! int]e/ & importance atta*$ to aviation1 t aft] ! w> is ov]1 l>ge comm]cial uses w develop :i* w (f] employm5t to ^? :o g into ! "w at ?is "t = milit>y reasons4 ,no "o c pr$ict exactly :at turn ! situation w take1 b !re is e indication t aviation has graduat$ f ! prim>y class ( exp]im5tal "w & is to be consid]$ n[ z an indu/ry along ) ! automobile bus9ess1 motor-boat bus9ess1 etc4 ,,*apt] ,,iii ,,pr9ciples ,,( ,,flight ,support ( an ,airplane by ,its ,w+s4--,an airplane is support$ j z def9itely z ?\gh on top ( a po/1 & by ! same law1 namely reaction4 ,if y try to sweep ! air d[nw>d ) a w+ held at a slight angle1 ! air j be=e x cons5ts to be pu%$ d[nw>d1 deliv]s a mom5t>y reaction :i* is upw>d4 ,if y h a bag ( air 9 y\r h& x ex]ts no pu% upw>d ( c\rse2 b ! m9ute y give x a quick pu% d[nw>d x resi/s1 due to its in]tia1 ?us deliv]+ an upw>d 8reaction0 aga9/ y\r h&4 ,:5ev] y move any?+1 x reacts an am\nt j equal to ! =ce t is mov+ x2 if y move a bullet out ( a gun1 j be=e />t+ ! bullet reacts & y h 8kick40 ,if y %\ld %oot a ?\s& guns d[nw>d1 ! reaction w\ld be consid]able1 & = ! in/ant might be suffici5t to support heavy weight4 ,! airplane is a device = pu%+ d[nw>d millions ( little bullets1 made out ( air & exce$+ly small & light4 ,! w+ ( an airplane sweeps ?r\gh ^! bullets1 or molecules1 ( air l a horizontal pl[1 w$ges ! p>ticles d[nw>d 9 va/ numb]s & 9 a cont9ual /ream1 mak+ up 9 am\nt :at is lack+ 9 weight1 s t z long z ! airplane ru%es along1 !re are _m ?\s&s ( cubic feet ( air =c$ d[n b5ea? its w+s1 deliv]+ up a reaction t results 9 complete support = ! ma*9e4 ,?is reaction is j z def9ite & secure z ?\gh ! ma*9e 7 support$ f ! gr\nd on :eels1 b x disappe>s entirely :5 ! airplane is at re/4 ,"p ( ! :ir ( a tra9+ ma*9e z x glides back to e>? is made by ! air driv5 d[nw>d f ! w+s2 ! same ph5om5on may be notic$ :5 a bat flies close to y\r e>s at night1 & if y 7 a few feet bel[ ! airplane z x flew1 y w\ld feel ! ru% ( air driv5 d[nw>d f its w+s 7see ,fig4 #af74 ,! net result ( all ! reactive pu%es f ?is air is lift4 ,x may am\nt to sev]al p\nds = e squ>e foot ( ! w+ surface4 ,?is is all t ne$ be said ab\t :y ! air supports an airplane2 all y h to rememb] is t z long z y h ! =w>d sweep+ movem5t1 y w h ! lift4 ,! =w>d movem5t is absolutely ess5tial1 h[ev]1 & to ma9ta9 x requires a lot ( horsep[] & gasol9e4 ,= x is by means ( ! eng9e & propell] t ?is =w>d movem5t is ma9ta9$4 ,! eng9e is a device = creat+ =w>d movem5t--! propell] drives ! ma*9e ahead 9 exactly ! same way z is ! case 9 a torp$o1 or /eamboat4 ,illu/ration3 ,,fig4 #af4--,relative pa? ( air p>ticles pa/ an airplane4 ,?is diagram illu/rates ! g5]al d[nw>d tr5d ( ! /ratum ( air met by ! w+s4 ,lift4--,assum+ t we h all ! =w>d motion ne$$1 let u n[ inve/igate ! lift t results4 ,exp]im5t]s su* z ! ,wrights & o!rs h f\nd out h[ to get ?is lift mo/ conv5i5tly4 ,lift dep5ds ^u ! f\r foll[+ factors3 #a4 ,area4 #b4 ,d5sity ( air4 #c4 ,angle ( incid5ce4 #d4 ,spe$ ( motion4 #a4 ,relation ( ,area ( ,w+s to ,support4--,consid] a small w+2 suppose x to be held by h& outside a tra9 w9d[ 9 a giv5 attitude1 its area be+ #a sq4 ft4 ,x t5ds to lift a c]ta9 am\nt1 say #e lb4 ,n[ increase its size to #b sq4 ft4 & x w lift ) #aj-lb4 =ce1 t5d+ to get away f y\r grasp4 ,rule3 ,:5 only ! area ( a w+ is *ang$1 its lift v>ies ) ! area4 ,if1 z above m5tion$1 y c get #e lb4 ( lift f ea* squ>e foot ( w+ surface1 y c by ! same sign get #aj-lb4 ( lift f #b sq4 ft4 ,& if y h #ejj sq4 ft4 ( surface y c get #bejj lb4 ( lift4 ,illu/ration3 ,,fig4 #ag4--;,diagram %[+ t 9 fa/ airplanes w+s are small2 9 sl[ airplanes w+s are l>ge4 7,above7 ,small w+s2 spe$ #aae mi4 p] hr42 = fight+4 ,"o seat4 7,bel[7 ,l>ge w+s2 spe$ #hj mi4 p] hr42 = reconnaissance4 ,two seats4 ,reg>d+ area ( w+ surface1 ! pilot does n h to worry 9 a flight s9ce he c d no?+ to *ange x anyway4 ,all he ne$s to "k is t 9 diff]5t airplanes small w+ area accompanies high spe$ & small weight-c>ry+ capacity1 z 9 ! case ( ! ,fokk] & ,sop) spe$ sc\ts 7see ,fig4 #ag74 ,conv]sely1 l>ge w+ areas are us$ = heavy load c>ry+ & sl[ spe$ 7see ,fig4 #ah74 ,spe$ & weight-c>ry+ capacity ?us appe> to be antagoni/ic & c n bo? be atta9$ ) effici5cy1 b only at ! exp5se ( enorm\s p[]4 ,! incompatibility betwe5 high spe$ & weight c>ry+ keeps ! design] busy 9 ef=ts t[>d a reconciliation4 ,illu/ration3 ,,fig4 #ah4--;,diagram %[+ use ( l>ge w+s = heavy airplanes1 & small w+s = light airplanes4 #b4 ,d5sity4--,! second factor affect+ ! lift is ! "* ( ! air itself4 ,i ref] to ! d5sity ( ! air4 ,! heavi] ea* p>ticle ( air becomes1 ! m reaction x c furni% to ! w+ t drives x d[nw>d2 s on days :5 ! b>omet] is high ! w+ w lift m ?an on o!r days4 ,n[ ! air is heavie/1 or mo/ d5se1 "r ne> ! gr\nd2 because 9 support+ ! #ej miles or s ( air above x1 x becomes compress$ & has m weight p] cubic foot4 ,!re=e1 ! w+ gets m lift at a l[ altitude ?an at a high4 ,"s airplanes w fly :5 l[ d[n b won't fly at all high up4 ,9 ,mexico1 = in/ance1 :5 ! punitive exp$ition />t$ out !y 7 already at an altitude ( sev]al ?\s& feet above sea level4 ,! airplanes _h be5 built = use at places l ,new ,york & ,engl&1 close to sea level1 & :5 our army (fic]s tri$ to fly ) !m 9 ,mexico1 !y w\ld n fly prop]ly1 & ! factory _h to r$esign !m4 ,reg>d+ d5sity1 ! pilot %\ld "k t = a l[ d5sity he %\ld !oretically get a high spe$4 ,z d5sity decreases1 high up 9 ! air1 ! spe$ t5ds to increase1 & moreov] he gets m spe$ = ! same am\nt ( gasol9e4 ,un=tunately1 at an altitude ! motor p[] falls (f1 s t n[adays ! spe$ is n fa/] high up ?an l[ d[n2 b :5 ! motor build]s succe$ 9 design+ _! motors to give ! same horsep[] at #bj1jjj ft4 z !y d on ! gr\nd1 airplanes w be able to rea* t]rific spe$ by do+ _! "w above ! cl\ds4 ,x is f\nd desirable to give l>ge w+s to airplanes :i* are go+ to fly at high altitudes1 s z to (fset ! lack ( d5sity by an increase 9 area1 ?us leav+ ! angle range--t is1 ! spe$ range--z l>ge z possible4 ,! army airplanes 9 ,mexico m5tion$ above 7 simply giv5 a new set ( l>g] w+s to (fset ! l[] air d5sity 9 ,mexico1 & !reaft] flew bett]4 #c4 ,angle ( ,incid5ce4--,! angle ( incid5ce is def9$ z ! angle betwe5 ! w+-*ord & ! l9e ( flight4 ,! l9e ( flight is ! direction ( motion ( ! airplane1 & is di/9ct f ! axis ( ! airplane :i* corresponds ) ! l9e ( flight only = a s+le angle ( incid5ce4 ,if ! l9e ( flight is horizontal1 ! airplane may be fly+ tail-high1 tail-level1 or tail-l[2 t is1 its axis may h v>y+ positions = a giv5 l9e ( flight4 ,?is is true1 if ! l9e ( flight is incl9$1 z 9 climb+4 ,x is a mi/ake to confuse ! l9e ( flight ) ! axis ( ! ma*9e4 ,! angle ( incid5ce ( ! w+s ( ! ,u4 ,s4 tra9+ ma*9e may h any value f #ae d[n4 ,:5 ! angle is small] ! lift ( ! w+s is small]4 ,consid] ! model w+ held out ( a tra9 w9d[2 if its front edge is tilt$ up to an angle ( #ae ) ! l9e ( motion x w lift say #a lb42 if r$uc$ to a #aj angle1 x w lift less1 say lb4 ,a model ( ! tra9+-ma*9e w+ c\ld be tilt$ d[n to an angle sev]al degrees less ?an z]o be=e its lift disappe>$1 because x is a curv$1 n a flat w+2 ?is angle w\ld be ! 8neutral-lift0 angle2 notice !n t ,o is n a neutral-lift angle1 & !re=e may be us$ 9 flight4 ,if ! model w+ 7 tilt$ up to an angle great] ?an #ae1 ! lift w\ld n increase any m1 b w\ld be f\nd to decrease4 ,= ?is w+1 #ae is call$ ! critical1 or 8,/all+0 angle1 beyond :i* x is unwise to g4 #d4 ,velocity4--,if ! model w+ :i* is imag9$ to be held out ( ! c> w9d[1 is held n[ 9 a fix$ position at a giv5 angle ( incid5ce1 any *ange ( ! tra9's spe$ w result 9 a *ange ( lift2 %\ld ! spe$ rise f #cj miles p] h\r to d\ble ?is value1 ! lift w\ld increase enorm\sly1 f\rfold 9 fact4 ,lift v>ies z ! squ>e ( ! spe$4 ,?us any increase or decrease ( spe$ results 9 a great increase or decrease ( lift4 ,int]dep5d5ce ( ,angle ( ,incid5ce & ,velocity4--,! f\r factors above m5tion$ all contribute to ! lift2 if 9 an airplane w+ ea* factor be giv5 a def9ite value1 ! result+ lift is det]m9$ accord+ to ! =mula3 ,l ,kr,a,v#b :]e ,l is lift4 ,k is a coeffici5t ref]r+ to ! angle4 ,a is ! area4 ,v is ! velocity4 r is ! d5sity4 ,two only ( ^! quantities *ange mat]ially 9 flight1 ! angle & ! velocity2 ! lift itself rema9s sub/antially ! same "u mo/ normal circum/ances4 ,! angle always *anges simultane\sly ) ! velocity1 increas+ :5 ! velocity decreases4 ,?us ! drop ( lift due to velocity decrease is balanc$ by ga9 ( lift due to angle increase1 & ! lift rema9s un*ang$ :5 spe$ *anges4 ,spe$ *ange !n requires t ! pilot alt] ! angle ( incid5ce simultane\sly ) ! ?rottle2 s !re are two ?+s to d1 unlike ! case ( ! automobile :]e only ! ?rottle is alt]$4 ,m9imum ,spe$4--,:51 9 sl[+ up an airplane1 ! angle ( incid5ce rea*es ! #ae limit1 no fur!r decrease ( spe$ is all[able2 !re=e1 ! critical angle det]m9es ! m9imum limit ( spe$4 ,if = any reason ! ma*9e exce$s ! #ae limit1 x mu/ spe$ up to ga9 support2 t is1 ! pilot has to increase angle & spe$ simultane\sly in/ead ( oppositely4 ,effici5cy ( ,airplane ,w+s4--,i said at ! beg9n+ ( ?is *apt] t ! airplane 0 a device = pu%+ d[n an enorm\s quantity ( air4 ,a c]ta9 am\nt ( =ce has to be furni%$ 9 ord] to keep ! airplane mov+1 & ?is =ce is furni%$ by ! eng9e & propell]4 ,! propell] by giv+ a c]ta9 am\nt ( pu% 9 a horizontal direction to ! airplane w+ enables ?is w+ to extract f ! air t5 or tw5ty times ?is am\nt ( pu% 9 a v]tical direction2 t is1 ! airplane w+ w give y #aj lb4 or m ( lift+ 9 ex*ange = #a lb4 ( pu%4 ,illu/ration3 ,,fig4 #ai4 ,lift & ,drift4--,lift is p]p5dicul> to l9e ( flight1 drift is p>allel4 ,angle ( ,incid5ce4--,w+ 9 position %[n has angle ( #e if mov+ 9 direction 8,a10 #aj if 9 direction 8,b20 & a negative angle ( #d if mov+ 9 direction 8,c40 ,9 ! la/ case x is mov+ along its neutral-lift-l9e1 lift becomes z]o4 ,! propell] pu% is necess>y to ov]come ! drift or resi/ance ( ! w+s to =w>d motion4 ,x appe>s !n t ! airplane w+ z x moves ?r\gh ! air has two =ces on x1 "o act+ /raight up & call$ 8lift10 ! o!r act+ /raight back & call$ 8drift0 7see ,fig4 #ai74 ,! lift is sev]al times great] ?an ! drift1 & ! situation is q analog\s to t ( a kite1 :i* rises upw>d 9 ! air due to its lift b at ! same "t drifts backw>d ) ! w9d due to its drift4 ,9 ! case ( ! kite ! /r+ takes up an angle :i* j balances ! jo9t effect ( ! lift & drift4 ,! effici5cy ( an airplane w+ is indicat$ by ! ratio ( lift to drift1 & = a giv5 lift1 ! effici5cy is be/1 !re=e1 = small drift4 ,if ! lift is #aijj lb4 & ! w+ drift #aij lb41 ,w+ effici5cy ,lift or weight_/,w+ drift #aijj_/aij #aj ,factors ,det]m9+ ,be/ ,effici5cy4--,x goes )\t say+ t an airplane w+ %\ld atta9 ! be/ effici5cy x c1 & !re are sev]al ways ( do+ ?is4 ,! fir/ relates to ! "q ( angle ( incid5ce2 we h already discuss$ ! effect ( angle on lift1 b :5 we come to discuss its effect on effici5cy we f9d t !re is only "o angle at :i* we c get ! be/ effici5cy4 ,?is is a small angle1 ab\t #c to #f2 at ?is angle ! lift is n[h]e ne> z mu* z x w\ld be at #aj or #ae1 b ! drift is s small comp>$ to ! lift t x is f\nd desirable 9 airplanes to employ ^! small angles = normal flight4 ,z ! angle increases above ?is value ( maximum effici5cy1 ! effici5cy drops (f1 & :5 y get up to ! /all+ angle1 ! effici5cy becomes v l[ inde$ 7see ,fig4 #bj74 ,illu/ration3 ,,fig4 #bj4--,w+ *>act]i/ics4 ,curves %[+ lift1 drift1 effici5cy1 & c5t] ( pressure travel ( typical tra9+-airplane w+1 z det]m9$ 9 ,a]odynamical ,laboratory4 ,! second way to get good effici5cy is to *oose ! %ape ( ! w+s prop]ly4 ,= in/ance1 e>ly exp]im5t]s tri$ to get results ) flat w+s1 & fail$ completely1 = ! flat w+ prov$ to be v ineffici5t4 ,:5 x 0 obs]v$ t birds _h curv$ w+s1 ?is pr9ciple 0 appli$ to e>ly exp]im5ts & !n = ! fir/ "t man 0 able to obta9 support 9 a fly+ ma*9e4 ,! fundam5tal pr9ciple ( effici5cy 9 w+s is t !y mu/ be curv$1 or camb]$1 z x is sometimes call$4 ,?is is because z ! w+ ru%es onw>d x wants to sweep ! air d[nw>d smoo?ly & )\t %ock1 z c be done only :5 ! w+ is curv$ 7see air fl[1 ,fig4 #ba74 ,illu/ration3 ,,fig4 #ba4--;,effici5cy ( curv$ & flat w+4 7a7 ,air fl[ pa/ curv$ w+ is smoo? )\t mu* eddy+2 7b7 air fl[ pa/ flat w+ produces eddies above x4 ,! "q ( w+ curvature is exce$+ly important !n2 we f9d t ! curvature ( its upp] surface is p>ticul>ly s4 ,we notice t airplane w+s all h a c]ta9 ?ickness 9 ord] to enclose ! sp>s & ribs2 x is n necess>ily a disadvantage = !m to be ?ick1 due to ! fact t ! upp] curve ( ! w+ does mo/ ( ! lift+ anyway1 & ! l[] side is relatively unimportant4 ,y c make ! l[] surface almo/ flat1 )\t mu* hurt+ ! effect ( ! w+1 s long z ! upp] surface rema9s prop]ly curv$4 ,h[ev]1 ! upp] surface mu/ be accurately %ap$1 & is s important t 9 "s ma*9es we f9d clo? is n reli$ on to ma9ta9 ?is delicate %ape1 b ?9 wood v5e] is us$ 7,i ref] to ! front upp] "p ( ! w+74 ,9 g5]al1 !n1 w+s are ?ick t[>d ! front & tap] d[n to a ?9 trail+ edge4 ,illu/ration3 ,,fig4 #bb4--;,diagram ( vacuum & pressure on airplane w+s4 ,note 9 biplane r$uc$ vacuum on bottom w+4 ,y may wond] h[ x 0 f\nd t ! upp] surface ( ! w+ 0 ! mo/ important2 & ,i w say t ?is 0 "o ( ! int]e/+ discov]ies ( ! e>ly hi/ory ( a]odynamics4 ,p at fir/ ?\ght t a w+ sweep+ ?r\gh ! air d]iv$ its support entirely f ! air :i* /ruck ! bottom ( ! w+1 & !y assum$ t if ! bottom ( ! w+ 7 prop]ly %ap$1 ! top did n matt]2 t is1 all ! pressure 9 ! air 0 deliv]$ up aga9/ ! bottom surface4 ,b a ,fr5* exp]im5t] conceiv$ ! idea ( ins]t+ little pressure gages at v>i\s po9ts ar\nd ! w+4 ,he f\nd1 x is true1 t !re 0 consid]able pressure ex]t$ 9 ! air aga9/ ! bottom ( ! w+2 b he f\nd a m surpris+ fact :5 he measur$ ! condition above ! w+4 ,:5 he appli$ 8 gage to ! upp] surface ( ! w+1 x read backw>d1 t is1 %[$ a vacuum1 & a v pron\nc$ "o4 ,he f\nd t !re 0 a vacuum suck+ ! top "p ( ! w+ upw>d twice z h>d z ! pressure und]nea? 0 pu%+2 s t two-?irds ( ! total lift on ?is w+ 0 due to vacuum above x 7see ,fig4 #bb74 ,9 ! diagram ! %ad$ area on top ( ! w+ repres5ts vacuum above1 t bel[ ! w+ repres5ts pressure b5ea?4 ,illu/ration3 ,,fig4 #bc4--,w+s ( small & l>ge aspect ratio ,aspect ,ratio4--,! ?ird factor 9 w+ effici5cy has to d ) ! plan %ape4 ,x 0 e>ly f\nd t squ>e w+s 7 n mu* good1 & t if y made !m wide 9 span l ^? ( a bird1 ! effici5cy 0 be/ 7see ,fig4 #bc74 ,aspect ratio is ! t]m :i* gives ! relation ( ! span to ! =e & aft dim5sion ( ! w+1 & ?is relation is usually equal to six or s4 ,! reason :y l>ge aspect ratios are advantage\s is z foll[s3 ,! tips ( all w+s are ineffici5t1 because !y all[ ! air to slip sideways ar\nd ! ends1 & !re is all ! tr\ble ( di/urb+ ?is air )\t extract+ any consid]able lift f x4 ,9 a wide-span w+ ^! ineffici5t w+ tips are only a small p]c5tage ( ! total area1 b 9 a small-span w+ !y may be an important consid]ation 7see ,fig4 #bd74 ,illu/ration3 ,,fig4 #bd4--;,diagram illu/rat+ aspect-ratio effect4 ,arr[s %[ direction ( air fl[ pa/ plate2 note t air escapes sideways ar\nd sides ( plate4 ,?is ph5om5on occurs at ! tips ( all airplane w+s & acc\nts = small effici5cy ( n>r[-span w+s4 ,w+ ,arrangem5ts4--,all ! =ego+ rem>ks 9 ?is *apt] h appli$ only to a s+le w+4 ,!y apply 9 g5]al to d\ble or triple w+s 7biplanes & triplanes71 b ! matt] ( arrang+ multiple w+s affects ! effici5cy4 ,! monoplane ) its s+le lay] ( w+s is ! mo/ effici5t type ( fly+ ma*9e4 ,we f9d if we arrange w+s into ! biplane %ape t ! pres5ce ( ! upp] w+ int]f]es ) ! vacuum =m$ above ! l[] w+1 & ! effici5cy decreases 7see ,fig4 #bb74 ,! same is true ( ! triplane & ! quadruplane arrangem5t4 ,if all we want$ 9 airplanes 0 effici5cy1 we w\ld use monoplanes1 b ! biplane is pretty popul> n[ 9 spite ( its l[ effici5cy2 ?is is because x c be mu* m /rongly truss$ ?an ! monoplane1 & also because ( ! fact t suffici5t area may be secur$ ) less span ( w+s4 ,x may be said t ! l[ effici5cy ( ! biplane c be some:at reliev$ by spac+ ! upp] & l[] w+s at a consid]able di/ance ap>t2 b if !y are spac$ at a di/ance mu* great] ?an ! *ord1 x requires extra long /ruts & wires1 & ! resi/ance & weight ( ^! w (fset ! advantage ( wid] spac+2 s t practically biplane-w+ effici5cy may be tak5 z #he p] c5t4 ( monoplane effici5cy4 ,x rema9s to m5tion ! t&em arrangem5t1 us$ 9 all airplanes1 :]e ! tail is a t&em surface 9 conjunction ) ! w+s4 ,a surface locat$ 9 ! position ( an airplane tail is at a disadvantage & %[s l[ effici5cy = flight purposes4 ,?is is because ! ma9 w+s deflect ! air d[nw>d & :5 ! tail comes along x meets air :i* has a m or less d[nw>d tr5d1 in/ead ( enc\nt]+ fre%1 undi/urb$ air 7see ,fig4 #af74 ,resi/ance ( an ,airplane to ,motion4--,e>li] 9 ?is *apt] ! support ( an airplane 0 expla9$ & x 0 se5 t ! weight 0 exactly equall$ by ! lift or support2 x 0 also expla9$ t ! production ( ?is lift requir$ consid]able =ce 9 mov+ ! w+s rapidly ?r\gh ! air4 ,x is n only ! w+s1 h[ev]1 :i* require =ce to ov]come ! resi/ance to motion4 ,9 ord] to h any w+s at all x is un=tunately necess>y to supply also /ruts1 wires1 etc41 = brac+ ^! w+s1 also a motor & seat = ! pass5g]1 :i* are usually includ$ inside a fuselage1 also :eels = l&+ & v>i\s control surfaces4 ,none ( ^! accessories to ! w+s contribute mat]ial lift1 b !y involve a l>ge am\nt ( resi/ance :i* is !re=e a dead loss4 ,note c>efully t !re are two di/9ct sorts ( resi/ance3 7#a7 t ( ! w+s1 :i* is ! necess>y price paid = secur+ lift2 7#b7 t ( all ! re/ ( ! ma*9e1 9 return = :i* no?+ b5eficial is receiv$1 & :i* !re=e has sometimes be5 call$ 8p>asite0 or 8deadhead0 resi/ance4 ,9 a typical tra9+ ma*9e ! total resi/ance to be ov]come if =w>d motion is ma9ta9$ is z foll[s3 7,see ,fig4 #bf47 ,at #gb miles p] h\r3 ,w+s #afj lb4 ,deadhead ,fuselage #ge resi/ance ,wir+ #gj ,/ruts #bj #aie ,miscellane\s ,balance #cj ------ ,total #cee lb4 ,at a spe$ ( #eg miles p] h\r3 ,w+s #aeh lb4 ,deadhead resi/ance #acj ------ ,total #bhh lb4 ,at a spe$ ( #dc miles p] h\r3 ,w+s #cej lb4 ,deadhead resi/ance #abe ------ ,total #dge lb4 ,x is se5 t ! above resi/ance values total to ! highe/ figure at ! l[e/ spe$1 & t ! l[e/ value ( resi/ance occurs at an int]m$iate spe$2 ! resi/ance decreases z ! spe$ decreases f #gc to #eg miles p] h\r2 b a fur!r decrease 9 spe$ f9ds ! resi/ance runn+ up rapidly s t at m9imum spe$ ! resi/ance is v great aga94 ,?is is due to ! fact t at high spe$s ! deadhead resi/ance exce$s t ( ! w+s b at sl[ spe$s al?\gh ! deadhead resi/ance is v small1 ! w+s be+ turn$ up to a l>ge angle )9 ! air1 h a resi/ance :i* is at its maximum4 ,?is seems cle> en\gh :5 we rememb] t ! lift ( ! w+s rema9s ! same z ! angle decreases 7& spe$ goes up7 b t ! effici5cy ( ! w+s increases s t ! w+ resi/ance is a small] fraction ( ! lift at high spe$ ?an at l[ spe$4 ,cause ( ,resi/ance4--,w+ resi/ance1 :i* is affect$1 z m5tion$ previ\sly1 by ! w+ curvature1 c n be decreas$ unless new & improv$ sorts ( w+s are inv5t$4 ,z to deadhead resi/ance1 x may be decreas$ 9 future by me?ods ( con/ruction :i* elim9ate uness5tial p>ts4 ,9 a high-spe$ airplane 9 ?is c\ntry an attempt 0 made to elim9ate ! wires altoge!r & mo/ ( ! /ruts 7because ! wir+ is "o ( ! l>ge/ s+le items ( deadhead resi/ance72 s f> ! attempt has fail$ = /ructural reasons4 ,9 ! monoplane type ( airplane ( c\rse ! /ruts are elim9at$1 :i* is an advantage f ! /&po9t ( resi/ance4 ,illu/ration3 ,,fig4 #be4--;,diagram illu/rat+ advantage ( /ream-l9e %ape4 ,note l>ge eddy di/urbance & vacuum beh9d r\nd %ape1 caus+ high resi/ance4 ,z long z /ruts1 wires1 etc41 are us$ at all1 ! m9imum resi/ance c be secur$ by giv+ !m a prop] 8/ream-l9e0 %ape4 ,! /ream-l9e %ape is "o 9 :i* ! ?icke/ "p is 9 front & tap]s (f to a po9t 9 ! re>1 l a fi%4 ,if1 = in/ance1 we take r\nd rods in/ead ( ! /ruts ( ! tra9+ ma*9e above m5tion$ & hav+ ! same ?ickness1 ! resi/ance might be #hj lb4 in/ead ( #bj lb42 & if we take a rod ^: %ape is elliptical ) its axes 9 a ratio ( #a to #e ! resi/ance might be #dj lb4 in/ead ( #bj lb42 & if we took ! /ream-l9e /ruts out ( ! tra9+ ma*9e & put !m back %>p edge =emo/1 ! resi/ance w\ld be increas$4 ,! advantage ( ! /ream-l9e %ape is t x provides smoo? l9es ( fl[ = ! air :i* has be5 ?ru/ aside at ! front to fl[ back aga9 )\t eddies to ! re>4 ,?is is n possible 9 ! case ( ! r\nd /rut1 beh9d :i* w be f\nd a :irl ( eddies result+ 9 a vacuum t t5ds to suck x backw>d4 ,by fa/5+ a /ream-l9e tail beh9d ! r\nd rod ! eddies are greatly r$uc$1 z is ! vacuum4 ,! wires ( ! airplane are subject to ! same law & if ! tra9+ ma*9e above m5tion$ _h /ream-l9e wires in/ead ( r\nd wires we might expect !m to h less ?an #gj lb4 resi/ance4 ,! fuselage %\ld always be giv5 z ne>ly a /ream-l9e %ape z ! pres5ce ( ! motor & tanks w p]mit2 & x mu/ all be inclos$ smoo?ly 9 8dop$0 fabric 9 ord] t ! air-fl[ ph5om5a may op]ate4 ,z = ! :eels1 !y mu/ ( necessity be r\nd1 b by enclos+ !m ) fabric ! air fl[ pa/ !m is m easy & ! resi/ance may be halv$4 ,total ,resi/ance4--,! necessity has be5 expla9$ ( discrim9at+ betwe5 w+ & deadhead resi/ance2 if we are talk+ ab\t w+s we may ignore ev]y?+ except ! w+ resi/ance 7commonly call$ 8w+ drift071 b if we are talk+ ab\t ! :ole airplane1 we !n mu/ ref] to ! total resi/ance1 :i* includes all ! o!rs & is ov]come by ! propell] ?ru/4 8,sk9-friction0 resi/ance has n be5 m5tion$ nor ne$ x be m ?an to say t any surface mov+ ?r\gh air attributes "p ( its resi/ance to ! actual friction ( ! air aga9/ x1 & !re=e %\ld be z smoo? z possible4 ,motor ,p[] ,requir$ = ,fly+4--,! reason resi/ance int]e/s u is t motor p[] is requir$ to propel ! airplane aga9/ x2 m & m p[] z ! resi/ance & spe$ increase4 ,obvi\sly1 ! p[] requir$ is lea/ :5 ! resi/ance is small1 i4e41 :5 ! spe$ is int]m$iate betwe5 m9imum & maximum4 ,x takes m p[] to fly at m9imum spe$ ?an at ?is int]m$iate spe$4 ,( c\rse x also takes m p[] to fly at maximum spe$1 :]e aga9 ! resi/ance is high4 ,maximum ,spe$4--,ord9>ily1 = mod]ate spe$s1 airplanes h a m>g9 ( p[] at :i* ! ?rottle ne$ n be op5$ wide2 %\ld spe$ be increas$ ! resi/ance & horsep[] requir$ w increase /eadily until ! ?rottle is wide op5 & motor 8full out20 ?is e/abli%es ! maximum spe$ ( an airplane2 !re is no m>g9 ( p[]1 no climb is possible4 ,! only way to increase spe$ is to use ! =ce ( gravity 9 addition to ! motor =ce4 ,x may be int]e/+ to "k :at is ! maximum possible spe$ 9 ! case ( a v]tical dive ) ! motor %ut (f2 x w be ab\t d\ble ! maximum horizontal spe$ z may be readily se5 f ! fact t ! ?ru/ 9 ! direction ( motion is n[ no long] horizontal & equal to ! resi/ance b is v]tical & equal to ! weight ( ! ma*9e2 t is1 ! ?ru/ may be increas$ fivefold1 & ! spe$ result+ w be increas$ correspond+ly1 if ! motor be runn+ 9 su* a v]tical dive ! velocity may be slightly increas$ ?\gh at ?is spe$ ( motion ! propell] w\ld n h mu* effici5cy4 ,!re is dang] 9 su* high spe$s2 ! /resses 9 ! ma*9e are increas$ sev]al times m]ely by ! increas$ resi/ance1 & if ! angle ( incid5ce %\ld be sudd5ly br\ght up to a l>ge value at ?is high spe$ ! /ress w\ld aga9 be increas$ s t ! total /ress increase !oretically might be z high z f\rte5 times ! normal value1 ?us exce$+ ! factor ( safety4 ,x is = su* reasons t ! maximum /r5g? is desirable 9 airplanes2 holes mu/ n be c>elessly drill$ 9 ! beams b %\ld be locat$ if any:]e midway betwe5 ! top & bottom edges1 :]e ! /ress w be lea/2 initial /resses1 due to tightness ( ! wires1 %\ld n be too great4 ,climb+ ,ability4--,climb+ ability ref]s to ! numb] ( feet ( rise p] m9ute or p] #aj m94 ,9 ord] to climb1 extra horsep[] is requir$ beyond t necess>y = m horizontal flight4 ,! ma*9e c1 = in/ance1 fly at #ef miles p] h\r at :i* spe$ x requires #dc hp4 ,if n[ ! ?rottle is op5$ up s z to increase ! horsep[] by #bb1 mak+ a total ( #fe hp41 ! ma*9e w climb at ! rate ( #chj ft4 p] m9ute1 ma9ta9+ approximately ! same flight spe$4 ,if in/ead ( #fe hp41 x 7 #ed hp4 ! spe$ ( climb w\ld be ab\t "o-half ( ! #chj1 or #aij ft4 p] m9ute2 ! flight spe$ aga9 rema9+ approximately z be=e2 t is1 any m>g9 ( horsep[] beyond ! p>ticul> value ( horsep[] requir$ may be us$ = climb+ )\t mat]ial *ange ( ! flight spe$4 ,x is necess>y "h to /ate t lift does n increase dur+ climb2 & :ile = ! in/ant t a climb comm5ces !re may be1 due to accel]ation1 m lift on ! w+s ?an balances ! weight1 ?is does n rema9 true aft] a /eady rate ( climb is rea*$4 ,to illu/rate1 9 a wagon drawn uphill by horses ! :eels :i* support ! wagon d n ex]t any m support ?an on ! level1 & ! entire =ce to make ! wagon asc5d is suppli$ ?r\gh extra h>d pull+ by ! horses4 ,?us 9 a climb+ airplane ! propell] furni%es all ! climb+ =ce & lift is no great] ?an 9 horizontal flight4 ,9 fact1 ! actual lift =ce may be ev5 less1 z ! weight ( ! airplane is p>tly support$ by ! propell] ?ru/ :i* is n[ incl9$ upw>d slightly4 ,to secure maximum climb+ ability1 we mu/ det]m9e at :at velocity ! m>g9 ( motor p[] is ! greate/4 ,9 ! above-m5tion$ ma*9e we "k t ! horsep[] requir$ = support is lea/ = a spe$ ( ne> #ee miles p] h\r1 & x is ne> spe$ :]e !re=e ! excess m>g9 ( p[] is greate/ & at :i* climb+ is be/ done4 ,an airplane design$ *iefly = climb+ mu/ h l[ values ( motor p[] necess>y = support1 namely1 mu/ h small resi/ance1 !re=e small size1 !re=e small weight4 ,illu/ration3 ,,fig4 #bf4--,p]=mance curves = typical tra9+ airplane4 ,glid+ ,angle4--,glid+ angle d5otes ! angle at :i* ! airplane w glide d[nw>d ) ! motor %ut (f & is spok5 ( z #a 9 #e1 #a 9 #f1 etc41 accord+ z x br+s ! airplane #a mile d[n = ea* #e1 #f1 etc41 miles ( travel 9 ! l9e ( flight4 ,! glid+ angle ( a ma*9e may be f\nd by divid+ ! total resi/ance into ! weight3 ,glid+ angle ,weight_/,total resi/ance4 ,9 ! above-m5tion$ airplane x is "o 9 #f4f :5 ! resi/ance is #bhh lb41 t is1 :5 ! spe$ is #eg miles p] h\r4 ,at any o!r spe$ ! resi/ance increases & h5ce ! glid+ angle decreases4 ,h5ce ! importance ( putt+ ! airplane into its prop] spe$ 9 ord] to secure ! be/ glid+ angle4 ,! ,propell]4--,! propell] or 8screw10 by screw+ its way =w>d ?r\gh ! air1 is able to propel ! airplane at ! desir$ velocity4 ,reg>d+ pr9ciples ( propell] action ! matt] c be ha/ily summ>iz$ 9 ! foll[+ brief l9es4 ,! propell] blades may be reg>d$ z little w+s mov+ 9 a circul> pa? ab\t ! %aft2 & !y h a lift & drift z d ! regul> w+s4 ,! lift is analog\s to ! ?ru/2 to secure ?is ?ru/ ) lea/ torque 7drift7 ! blades are set at _! mo/ effici5t angle ( incid5ce1 & :ile ! blade appe>s to h a /eep angle ne> ! hub1 x actually meets ! air 9 flight at ! same angle ( incid5ce f hub to tip4 ,propell] ,pit*4--,pit* is be/ def9$ by analogy to an ord9>y wood-screw2 if ! screw is turn$ "o revolution x advances into ! wood by an am\nt equal to its pit*4 ,if ! air 7 solid1 a propell] w\ld d ! same1 & ! di/ance might be #h ft41 say4 ,actually ! air yields1 & slips backw>d1 & ! propell] advances only #f ft4 ,its 8slip0 is !n #h m9us #f1 equals #b ft41 or #be p] c5t4 ,su* a propell] has an #h-;ft4 pit*1 & a #be p] c5t4 slip4 ,?is 8slip /ream0 bl[s backw>d 9 a flight s t ! tail ( an airplane has air slipp+ pa/ x fa/] ?an d ! w+s4 ,h5ce ! air =ces at ! tail are great] ?an might be expect$4 ,! rudd] & elevators !re=e give a quick] action :5 ! propell] is rotat+ ?an :51 z 9 ! case ( a glide1 x is n4 ,illu/ration3 ,,fig4 #bg4--,wa%\t 9 left-w+ tips4 ,wa%\t4--,due to torque ( ! motor1 ! airplane t5ds to rotate 9 ! opposite direction to ! propell]4 ,?is t5d5cy may be neutraliz$ by giv+ "o w+ tip a small] angle ( incid5ce1 call$ 8wa%\t10 s t ! ma*9e normally t5ds to neutralize ! torque-effect4 ,,pr9ciples ,,( ,,airplane ,,equilibrium ,illu/ration3 ,,fig4 #bh4--;,balances ( =ces 9 an airplane4 ,weight =w>d ( lift1 ?ru/ bel[ resi/ance4 ,?ru/ equals resi/ance1 weight equals lift4 ,introductory4--,"u ?is head w be discuss$3 7a7 features ( airplane design :i* t5d to ma9ta9 equilibrium irrespective ( ! pilot2 7b7 matt]s ( volunt>y controll+ op]ations by ! pilot4 ,z reg>ds 7a7 ! t5d5cy ( ! airplane t[>d inh]5t /ability acts to oppose any deviation f its c\rse :e!r ! pilot s desires or n4 ,! m /able is a ma*9e1 ! less delicately is x controll$1 & ! pres5t cons5sus ( op9ion among pilots is t a #ej-ej compromise betwe5 /ability & controllability is ! be/ ?+4 ,9 que/ions ( airplane equilibrium ! />t+ po9t is ! c5t] ( gravity2 obvi\sly1 if ! c5t] ( gravity 7 back at ! tail or up at ! nose !re w\ld be no balance2 ! prop] place = x is ! same spot :]e all ! o!r =ces su* z ?ru/1 lift & resi/ance act2 !re x is easy to balance !m all up4 ,b x is n always easy to br+ ! l9e ( ?ru/ & ! l9e ( total resi/ance into co9cid5ce1 because ! l9e ( ?ru/ is ! l9e ( ! propell] %aft & :5 ?is is high up z 9 ! case ( "s pu%]s x may be sev]al in*es above ! l9e ( resi/ance4 ,& z ! ?ru/ is above ! resi/ance !re is a t5d5cy to nose ! ma*9e d[n2 to balance :i* ! design] delib]ately locates ! c5t] ( gravity suffici5tly f> beh9d ! c5t] ( lift s t !re is an equal t5d5cy to tip ! nose upw>d2 & all f\r =ces m5tion$ completely balance ea* o!r4 ,b ?+s may happ5 to *ange ! am\nt or position ( ^! =ces dur+ flight1 & if ?is does happ5 ! fir/ ?+ to d is to re/ore ! balance by br++ 9 a small new =ce some:]e4 ,9 an actual airplane ?is small re/or+ =ce is suppli$ at ea* critical mom5t fir/1 by ! tail1 etc41 ( ! airplane & second1 by volunt>y actions ( ! pilot4 ,! c5t] ( gravity ( any airplane may be det]m9$ easily by putt+ a roll] "u x & see+ :]e x w balance1 or by gett+ ! am\nt ( weight support$ at ! :eels & tail1 accord+ to ! me?od ( mom5ts4 ,longitud9al ,/ability4--,longitud9al /ability has to d ) ! t5d5cy ( an airplane to ma9ta9 its prop] pit*+ angle4 ,x 0 said above t ! f\r =ces ( lift1 resi/ance1 ?ru/ & weight always exactly balanc$ due to _! size & _! position4 ,n[ ! fir/ consid]ation ab\t longitud9al /ability is t :ile ! c5t]s ( gravity & o!r =ces rema9 9 a fix$ position1 ! c5t] ( lift *anges its position :5ev] ! angle ( incid5ce 7t is ! spe$7 is *ang$4 ,! ph5om5on ( %ift ( c5t] ( pressure applies only to ! w+s & to ! lift 7! position ( c5t] ( resi/ance rema9s practically fix$ at all angles74 ,note ! effect on c5t] ( pressure position ( a *ange ( w+ angle 7see ,fig4 #bj74 ,! w+ us$ on ! ,u4 ,s4 tra9+ ma*9e has a c5t] ( lift :i* is ab\t 9 ! middle ( ! w+ :5 fly+ at a small angle ( maximum spe$2 b if ! angle is increas$ to ! /all+ angle ( #ae1 ! c5t] ( pressure moves f midway ( ! w+ to a po9t :i* is ab\t "o-?ird ! *ord di/ance ( ! w+ f ! front edge4 ,! lift may travel ab\t foot1 & x is equal 9 am\nt to ! weight ( ! ma*9e 7t is1 ne>ly a ton71 & ! m]e effect ( *ang+ ! angle f its m9imum to its maximum value !re=e t5ds to di/urb ! longitud9al equilibrium ) a =ce :i* may be repres5t$ z #a ton act+ on a lev] arm ( ft4 ,suppose t ! airplane is balanc+ at an angle ( #b s t ! c5t] ( gravity co9cides ) ! c5t] ( lift = ?is angle2 n[ if a gu/ ( w9d causes ! angle to increase = an in/ant to #b1 ! c5t] ( lift w move =w>d & t5d to pu% ! front edge ( ! w+ up1 ?us increas+ ! angle fur!r to #b4 ,!n ! c5t] ( lift1 ( c\rse1 moves fur!r =w>d to accommodate ! increase ( angle1 & 9 a fraction ( a second ! w+ w\ld re> up unless x 7 firmly atta*$ to ! airplane body & held 9 its prop] position by ! tail4 ,simil>ly if = any reason ! prop] angle ( #b 7 decreas$1 ! same upset w\ld foll[1 only ?is "t t5d+ to dive ! w+ viol5tly to e>?4 ,?is t5d5cy is neutraliz$ 9 an airplane by ! 8,p5aud ,tail ,pr9ciple40 ,!re are c]ta9 %apes ( w+s 9 :i* ! c5t] ( pressure travels 9 ! rev]se direction2 a flat plate1 = example2 or a w+ hav+ its re> edge turn$ up s t ! g5]al w+ %ape is l a ?9 lett] 8,s40 ,su* w+s z ^! w\ld n t5d to lose _! prop] angle1 because :5 ! angle is *ang$ = any reason ! c5t] or pressure 9 ^! w+s moves 9 j ! mann] necess>y to re/ore !m to _! prop] position2 b ^! w+s are ineffici5t & are n 9 pres5t use on airplanes4 ,illu/ration3 ,,fig4 #bi4--;,diagrams illu/rat+ !ory & application ( longitud9al dih$ral angle4 ,! ,p5aud ,tail ,pr9ciple4--,rule4--,! horizontal tail mu/ h a small] angle ( incid5ce ?an ! w+s4 ,! upsett+ =ce above m5tion$ mu/ be met by a /rong opposite right+ =ce1 & ?is latt] is furni%$ by ! horizontal tail surface4 ,9 ! angle ( equilibrium ( #b above m5tion$1 ! flat horizontal /abiliz] w p]haps h no =ce act+ on x at all because x is edgewise to ! air & its angle ( incid5ce is z]o4 ,:5 ! angle ( ! w+ increases to #b & ! lift moves =w>d t5d+ to re> x up1 ! w+ be+ rigidly fa/5$ to ! body pu%es ! tail d[nw>d s t ! tail n[ beg9s to h a small lift =ce ^u x due to its angle ( 2 & ?is newly creat$ =ce1 ?\gh small1 acts at su* a long lev] arm t x exce$s ! re>+ =ce ( ! w+ & w quickly re/ore ! airplane to #b4 ,?is action dep5ds ^u ! pr9ciple ( ! ,p5aud ,tail or longitud9al 8,dih$ral0 :i* requires t ! front w+s ( an airplane make a l>g] angle ) ! w9d ?an ! re> surface4 ,?is pr9ciple holds good ev5 :5 we h re> surfaces :i* actually are lift+ surfaces 9 normal flight1 ! requisite be+ t ! w+s !mselves %all 9 su* cases be at an ev5 great] angle ?an ! tail4 ,no m5tion has be5 made ( ! elevator control1 because its action is additional to ! above-m5tion$ /ability4 ,! elevator is able to alt] ! lift on ! tail2 su* alt]ation requires1 ( c\rse1 imm$iate *ange ( angle ( ! w+s s t equilibrium %all aga9 foll[2 & ?is equilibrium w be ma9ta9$ until ! lift at ! tail is aga9 alt]$ by "s movem5t ( ! elevator control4 ,?us ! elevator may be consid]$ z a device = adju/+ ! angle ( incid5ce ( ! w+s4 ,! air ?r\gh :i* ! w+s h pass$ receives d[nw>d motion1 & !re=e a tail :i* is pois$ at z]o angle ) ! l9e ( flight may actually receive air at an angle ( -#b or -#c4 ,9 ! above case we w\ld expect an actual d[nw>d =ce on ! tail1 unless ?is tail is giv5 a slight ar* on its top surface 7= x is kn[n t ar*$ surfaces h an angle ( z]o lift :i* is negative angle74 ,longitud9al ,control4--,/e]+ up or d[n is done by ! elevator1 :i* z expla9$ above is m]ely a device = adju/+ ! angle ( incid5ce ( ! w+s4 ,! elevator controls l all ! o!r controls ( an airplane dep5d = _! quick effici5t action ^u g5]\s spe$2 !y c n be expect$ to give good response :5 ! ma*9e is ne> its /all+ spe$4 ,! elevators l ! rudd] are locat$ directly 9 ! bla/ ( ! propell] & 9 case ! spe$ ( motion %\ld become v sl[1 ! elevators may be made to ex]t consid]able controll+ =ce if ! motor is op5$ up to bl[ a /rong bla/ aga9/ !m4 ,?is is good to be> 9 m9d :5 taxy+ on ! gr\nd because if ! motor is %ut (f at ! sl[ spe$ ( motion ! elevator & rudd] w lose _! efficacy4 ,! propell] bla/1 due to a #be p] c5t4 slip1 adds #be p] c5t4 ( app>5t spe$ to ^? p>ts :i* are 9 its way1 & !re=e ! tail =ces are affect$ z ! squ>e ( ?is increase1 t is1 ! =ces may be #ej p] c5t4 great] ) ! propell] on ?an (f4 ,lat]al ,/ability4--,?is dep5ds ^u ! keel surface or total side area ( an airplane4 ,! keel surface includes all ! /ruts1 wires1 :eels1 w+s1 z well z body1 aga9/ :i* a side w9d c bl[4 ,skidd+ & side-slipp+ h ! same effect z a side w9d1 & ! result+ =ces act+ aga9/ ! side ( ! ma*9e %\ld be made useful in/ead ( h>mful4 ,?is is done by prop]ly proportion+ ! keel or side surface4 ,if keel surface is l[1 ! side =ce w rotate ! airplane ab\t its axis s t ! w9dw>d w+ s9ks2 if high1 s t x rises4 ,b if ! keel surface is at j ! "r height 7i4e41 level ) ! c5t] ( gravity7 ! side =ces w n rotate ! ma*9e at all & w simply oppose ! skidd+ )\t upsett+ equilibrium4 ,illu/ration3 ,,fig4 #cj4--;,diagram %[+ effect on lat]al /ability ( dih$ral angle & non-skid f9s4 7a7 ,ma*9e fly+ level4 7b7 ,ma*9e tips & side-slips3 excess pressure is creat$ on w9dw>d w+ & f9s1 7c7 ,ma*9e has side-slipp$ & rotat$ back to level4 ,lat]al ,dih$ral4--,n[ :5 an airplane appe>s to h its keel-surface c5t] too l[1 ! easie/ way to raise x level ) ! c5t] ( gravity is to give ! w+s a dih$ral angle1 t is make !m po9t upw>d & outw>d f ! body4 ,?us _! projection1 z se5 9 a side view1 is increas$1 & ! effect is to add "s keel surface above ! c5t] ( gravity1 ?us rais+ ! c5t] ( total keel surface4 ,a fur!r advantage ( ! lat]al dih$ral is t any li/ ( ! airplane sideways is automatically correct$ 7see ,fig4 #cj74 ,! l[ w+ supports bett] ?an ! high w+1 because a side slip sets 91 h5ce w re/ore ! airplane to level position4 ,non-,skid-,f9s4--,:]e = ! above-m5tion$ purposes an excessive dih$ral w\ld be ne$$1 resort may be _h to non-skid-f9s erect$ v]tically edgewise to ! l9e ( flight above or b5ea? ! topw+4 ,^! are us$ 9 m>9e ma*9es to balance ! abnormally l>ge keel surface ( ! boat or pontoon bel[4 ,lat]al ,control4--,by means ( ail]ons1 lat]al control is ma9ta9$ volunt>ily by ! pilot2 ! ail]on on ! l[ tip is giv5 a great] angle ( incid5ce :ile on ! high tip a less angle ( incid5ce ?us re/or+ ! prop] level ( ! ma*9e4 ,notice t ! efficacy ( ! ail]ons dep5ds ^u spe$ ( motion ( ! airplane1 irrespective ( propell] slip because ! propell] slip does n rea* ! ail]ons4 ,!re=e1 at /all+ spe$s ! ail]ons may n be expect$ to "w at _! be/1 & :5 lat]al balance is upset at sl[ spe$s x is necess>y to dive ! ma*9e be=e en\gh lat]al control c be secur$ to re/ore ! balance4 ,illu/ration3 ,,fig4 #ca4--;,dep]duss9 control4 ,sy/em us$ 9 ,u4 ,s4 tra9+ airplanes4 ,directional ,/ability4--,directional /ability has to d ) ! t5d5cy ( an airplane to sw]ve to ! "r or left ( its prop] c\rse4 ,to ma9ta9 directional /ability ! 8v]tical /abiliz]0 is us$1 :i* acts 9 a mann] analog\s to ! fea!r on an arr[4 ,?us 9 case ( a side slip ! tail w sw+ & =ce ! airplane nose ar\nd into ! direction ( ! side slip s t ! airplane t5ds to meet ! relative side w9d 8nose-on0 z x %\ld4 ,! v]tical /abiliz] %\ld n be too l>ge1 h[ev]1 z !n any side pressure due to deviation f a rectil9e> c\rse w cause ! ma*9e to sw]ve viol5tly2 ! w+ :i* is out]mo/ 9 ! turn w h prepond]ance ( lift due to its high] spe$2 t is1 ! airplane w get into a turn :]e !re is too mu* bank & a spiral dive may result4 ,directional ,control4--,! rudd] gives directional control 9 exactly ! same way t x does on a boat2 x %\ld be said1 h[ev]1 t ! rudd] is sometimes us$ )\t any int5tion ( *ang+ ! direction1 t is1 x is us$ simultane\sly ) ! ail]ons z a means ( neutraliz+ _! sw]v+ t5d5cy4 ,! ail]ons1 ( c\rse1 at ! same "t t !y re/ore lat]al balance create a disadvantage\s t5d5cy to sw]ve ! ma*9e away f its directional c\rse2 t is :at ! rudd] mu/ neutralize4 ,moreov]1 ! rudd] is frequ5tly us$ aga9/ side w9ds to ma9ta9 rectil9e> motion4 ,bank+4--,bank+ comb9es ! lat]al & directional control1 :i* %\ld be op]at$ simultane\sly s z to tilt ! ma*9e & at ! same "t ma9ta9 ! radius ( turn4 ,! w+s are tilt$ 9 a bank because 9 go+ ar\nd a curve ( a c]ta9 radius ! weight ( ! ma*9e creates a c5trifugal =ce 9 a horizontal direction & if ! curv$ pa? is to be ma9ta9$ ?is c5trifugal =ce mu/ be neutraliz$2 & ?is is done by incl9+ ! =ce ( lift inw>d until x has a horizontal compon5t equal to ! c5trifugal =ce4 ,t is :y ! angle ( bank mu/ be rigidly obs]v$1 or else ! inw>d compon5t ( ! lift w *ange4 ,n[ z soon z ! w+s bank up1 ! lift =ce is no long] all v]tical & !re=e may n be en\gh to support ! weight ( ! ma*9e4 ,to (fset ?is h pl5ty ( motor p[] = spe$ 9 a bank2 & d n try to climb :ile bank+4 ,x is bett] to bank too little ?an too mu*2 too little results 9 skidd+ :i* may be easily cur$2 too mu* results 9 side slipp+ inw>d & if ! tail surface is too great 9 ?is latt] case1 a spiral dive may result--s look out = ov] bank+4 ,x is bett] = ! beg9n] 9 bank+ to move 8 ail]ons fir/ & !n move ! rudd]2 = if he moves ! rudd] fir/ !re w be skidd+ outw>d1 =w>d spe$ w drop & a /all may result4 ,on high angles ( bank+1 ov] #de1 x %\ld be not$ t ! elevators are n[ m ne>ly v]tical ?an horizontal & op]ate z a rudd]2 simil>ly ! rudd]'s function is rev]s$1 & to turn d[n ! rudd] w be us$4 ,damp+ 9 an ,airplane4--,above h be5 m5tion$ ! re/or+ =ces :i* t5d t[>d airplane equilibrium4 ,n[ ^! re/or+ =ces t5d to pu% ! ma*9e back to equilibrium & ev5 beyond 9 exactly ! same way t gravity causes a p5dulum to sw+ ab\t its po9t ( equilibrium4 ,?is c sometimes be notic$ 9 ! case ( an automobile :5 travell+ at high spe$ along c\ntry roads :]e a sort ( sl[ oscillation f side to side may be notic$ due to ! =ceful ma9t5ance ( equilibrium ( ! body 9 its =w>d motion4 ,?is oscillation 9 an airplane w\ld be s]i\s unless !re 7 means ( damp+ x out & ^! means are3 fir/1 ! w+s2 second1 ! tail surfaces2 ?ird1 ! weight & in]tia ( ! ma*9e itself4 ,reg>d+ in]tia x %\ld be said t a ma*9e ) weight di/ribut$ f> f ! c5t] ( gravity1 su* z ! d\ble-motor airplane has a l>ge t5d5cy to resi/ ! roll+ motions associat$ ) lat]al /ability4 ,b f ! same sign airplanes ) l>ge mom5t ( in]tia are difficult to deviate f any giv5 attitude1 & !re=e h ! "n ( be+ 8logy40 ,! prop] proportion+ ( an airplane's p>ts to secure fir/1 ! re/or+ =ces2 second1 ! prop] damp+ =ce2 ?ird1 ! prop] am\nt ( mom5t ( in]tia1 is a v delicate matt] & beyond ! scope ( ! pres5t *apt]4 ,,*apt] ,,iv ,,fly+ ,,! ,,airplane ,/>t+ ,(f4--,! fir/ ?+ to d be=e />t+ (f 9 an airplane is to inspect c>efully ev]y?+ ab\t ! ma*9e & assure y\rself t x is 9 p]fect condition4 ,:5 all is ready to />t turn ! ma*9e directly aga9/ ! w9d2 ?is is done 9 ord] t ! rise f ! gr\nd may be m quickly made ) ! assi/ance ( ! w9d "u ! w+s1 & x has a m important advantage 9 ! fact t if y try to get (f ! gr\nd across ! w9d ! ma*9e w be v h>d to balance4 ,birds also take ! air directly aga9/ ! w9d ev5 ?\gh = ! mom5t ?is c>ries !m 9 a direction t[>d "s suppos$ enemy1 & x is a fundam5tal pr9ciple 9 airdromes4 ,keep ! ma*9e po9t$ into ! w9d = ! fir/ #bjj ft4 ( altitude 7& simil>ly 9 l&+ face ! w9d :5 )9 #bjj feet ( ! gr\nd74 ,9 case ! eng9e %\ld fail be=e a height ( #bjj ft4 is rea*$1 nev] turn d[n w9d z ?is is extremely dang]\s4 ,assi/ance w be _h = ! />t f ! me*anics1 or if away f ! airdrome f by/&]s4 ,h ea* assi/ant 9 8 prop] place be=e />t+ ! eng9e2 "o is to />t ! propell] & ! re/ to hold back ! ma*9e until ready to let g4 ,illu/ration3 7,f 8,h[ to ,in/ruct 9 ,fly+407 ,,fig4 #cb4--;,airplane 9 fly+ position j aft] />t+4 ,?is cut also illu/rates prop] l&+ attitude1 s9ce airplane is j skimm+ ! gr\nd4 ,9 ord] to get (f ! gr\nd y w want good eng9e p[]2 x takes consid]able ?ru/ to accel]ate an airplane on ! gr\nd to its fly+ spe$2 9 fact ! fir/ fly+ ma*9e ( ! ,wrights _h to use an auxili>y catapult to furni% ! ?ru/ necess>y to get !m into ! air4 ,mak+ sure t ! motor is giv+ full p[] raise ! h& z a signal to ! att5dants to remove ! *ocks & let g4 ,z y />t roll+ =w>d pu% ! control lev] =w>d :i* w raise ! tail (f ! gr\nd & place ! w+s edgewise to ! w9d :ile !y w n (f] resi/ance to ! acquir+ ( good roll+ spe$4 ,)9 a few seconds ! ma*9e w h atta9$ on ! gr\nd a velocity n less ?an ! l[ fly+ spe$2 x w n rise1 h[ev]1 until ! tail is l[]$ by pull+ ! lev] back4 ,:5 ! necess>y roll+ spe$ is atta9$ pull ! lev] s(tly backw>d2 ! tail at once drops1 ! w+s increase _! angle & lift & ! ma*9e w rise1 ! lev] be+ held 9 a fix$ position 7see ,fig4 #cb74 ,! di/ance betwe5 ! po9t ( />t+ & ris+ w be #ajj yd4 or m & w occupy f #e to #aj sec4 dep5d+ on ! w9d4 ,! *ange f fly+ position to climb+ position is only a slight modification involv+ only a slight pull+ back ( ! control lev] & hold+ x 9 fix$ position2 ! motor may 9 "s ma*9es simply be op5$ out :5 its increas$ p[] w make ! ma*9e rise2 h[ev]1 !re is only "o spe$ at :i* ! climb w be fa/e/ & !re=e x is well to "k :at is ! prop] spe$ = climb+2 ! motor is !n op5$ out full & ! airplane op]at$ to give ! prop] spe$ correspond+4 ,! pupil %\ld rise to ! height ( at lea/ #ajj ft41 z any less is useless & no?+ w be le>n$ f l&+4 ,9 ! case ( cross-c\ntry fly+ ! pilot w rise to ! height ( #bjjj ft41 circl+ ov] ! field r ?an fly+ (f 9 a /raight l9e s t prep>atory to 8 />t he always has ! fly+ field 9 rea*4 ,illu/ration3 7,f 8,h[ to ,in/ruct 9 ,fly+407 ,,fig4 #cc4--;,airplane 9 glid+ position1 approa*+ a l&+4 ,note t its attitude relative to l9e ( flight is simil> to 8fly+ position10 l9e ( flight h[ev] be+ incl9$4 ,l&+4--,prop] l&+ is ! mo/ important ?+ 9 airplane fly+4 ,! pilot 9 turn+ 8 ma*9e d[nw>d t[>d a l&+ spot f flight w *oose a di/ance f ! field equival5t to ! prop] glid+ angle ( 8 ma*9e4 ,if ! glid+ angle is #a 9 #g he mu/ n turn d[nw>d any fur!r f ! field ?an a di/ance great] ?an sev5 times 8 altitude or he w fall %ort4 ,x is saf] to come clos] to ! field be=e turn+ d[nw>d = two reasons3 fir/1 because y may n be glid+ at ! be/ glid+ angle2 second1 because y c always kill extra height by a spiral or two bett] ?an y c rega9 x4 ,h height to sp>e :5 l&+4 ,to come d[n ?rottle d[n ! eng9e & pu% ! lev] s(tly =w>d until ! prop] glid+ angle is obta9$ 7,fig4 #cc74 ,! reason = ?rottl+ d[n ! eng9e is3 fir/1 t y d n ne$ its ?ru/ :5 y are coa/+ d[n because gravity furni%es all ! necess>y velocity2 second1 if y glide or dive ) ! motor wide op5 high spe$ w result1 result+ 9 /ra9s on ! ma*9e especially on ! mom5t ( level+ out aga92 ?ird1 at ?is high spe$ ! controls become /iff to op]ate4 ,illu/ration3 ,,fig4 #cd4--;,attitudes ( an airplane 9 flight4 ,ma9ta9 ! prop] glid+ spe$ to )9 #e miles an h\r ( :at x ought to be z x is ! spe$ :i* det]m9es ! prop] glid+ angle4 ,! revolution c\nt] w indicate :at ! spe$ is or ! air-spe$ met] may be us$4 ,arrange to come on to ! field fac+ directly into ! w9d1 :i* may be obs]v$ by wat*+ smoke or flags bel[4 ,9 l&+ aga9/ ! w9d y are aga9 copy+ ! practice ( ! birds4 ,:5 y come to )9 #ae ft4 ( ! gr\nd pull ! lev] s(tly back until ! ma*9e is 9 its sl[-fly+ position1 :i* %\ld be atta9$ #e ft4 above ! gr\nd 7,fig4 #cd74 ,hold ! /ick at ?is position ( horizontal fly+2 no fur!r movem5t ( ! lev] is necess>y except to correct bumps1 = :i* purpose x w\ld be held lightly = in/ant action4 ,! ail]on control mu/ be us$ "h to keep ! ma*9e level & x may be necess>y to op]ate ! rudd] aft] t\*+ ! gr\nd 9 ord] to avoid sw]v+2 9 fact "s ma*9es are provid$ ) a re> skid :i* /e]s = ?is purpose4 ,9 roll+ j aft] l&+ keep ! tail z close to ! gr\nd z possible )\t caus+ undue bump+1 s t ! maximum resi/ance ( ! w+s may be pres5t$ to ! air & ! ma*9e be sl[$ up rapidly4 ,"s ma*9es are fitt$ ) brakes on ! :eels to assi/ 9 ! quick ret>dation ( ! roll4 ,l&+ is "o ( ! bigge/ problems 9 aviation & is a h>d ?+ to le>n because x is done at a high spe$ especially 9 ! fa/ milit>y ma*9es su* z ! ,fokk]1 ,nieuport1 etc4 ,l&+ is m ( a problem ?an x us$ to be 9 ! e>ly days :51 = in/ance1 ! ,wrights 7 able to l& )\t any :eels at all on m]e skids because _! ma*9es 7 n fa/4 ,! foll[+ are examples ( bad l&+s3 #a4 ,! pancake results f all[+ ! ma*9e to get into its ris+ position :5 x is l&+ 7,fig4 #ce74 ,!re w be a p]p5dicul> b\nce & on ! second b\nce ! runn+ ge> w break4 ,9 ord] to get out ( an imm95t pancake op5 up ! eng9e to keep ma*9e fly+1 put ! ma*9e into a fly+ position1 !n ?rottle d[n aga9 & l&4 #b4 ,ano!r type ( pancake results f br++ ! ma*9e out ( its glid+ position at a po9t too f> above ! gr\nd :5 ! ma*9e w drop due to lack ( spe$ & break ! runn+ ge>4 ,to avoid ?is op5 motor full1 ?us rega9+ spe$ & fly+ position2 aft]w>d ?rottle d[n & rel&4 ,illu/ration3 7,f 8,h[ to ,in/ruct 9 ,fly+407 ,,fig4 #ce4--;,bad l&+1 ,type #a--! 8pancake0 l&+4 ,l9e ( flight is d[nw>d2 angle ( incid5ce l>ge1 h5ce spe$ is sl[2 b !re is too mu* d[nw>d mom5tum & l&+ ge> w break4 ,%\ld l9e ( flight arr[ po9t upw>d1 airplane z %[n w\ld !n be 9 climb+ position4 #c4 ,a ?ird type ( bad l&+ results f failure to turn ! ma*9e out ( its glide at all1 s t x glides /raight d[nw>d until x t\*es ! gr\nd4 ,?is is ! mo/ dang]\s case ( all ! bad l&+s4 ,to cure x op5 up ! eng9e aft] ! fir/ b\nce1 rega9+ fly+ spe$ be=e ! second b\nce2 !n rel&4 ,illu/ration3 7,f 8,h[ to ,in/ruct 9 ,fly+407 ,,fig4 #cf4--;,bad l&+ ,type #d--ma*9e n level4 ,:eels d n t\* gr\nd at same "t1 & "o may sma%4 #d4 ,if at ! mom5t ( l&+ ! rudd] is turn$ caus+ ma*9e to sw]ve1 or if ! ma*9e is n level1 a side /ra9 w be plac$ ^u ! l&+ ge> & ! :eels w buckle 7,fig4 #cf74 ,,*apt] ,v ,,cross-,,c\ntry ,,fly+ ,cross-c\ntry fly+ diff]s f ord9>y airdrome fly+ 9 t x takes y a long way (f f y\r l&+ field4 ,on ! airdrome y\r *ief anxiety is to le>n h[ to fly1 h[ to "w ! controls1 h[ to bank2 b 9 cross-c\ntry "w1 y are suppos$ to h all ! te*nique ( airplane op]ation well 9 h&1 s t y d n h to ?9k mu* ab\t x4 ,9 cross-c\ntry fly+1 !n1 y\r *ief anxiety w be to arrive at y\r de/9ation & to be con/antly se>*+ out available l&+ fields 9 case ( eng9e failure4 ,! fir/ cross-c\ntry flight y make may be a %ort1 easy "o1 9 :i* !re are pl5ty ( available l&+ places1 & on :i* y w be able to make a regul> reconnaissance report4 ,fur!r exp]i5ce 9 cross-c\ntry "w w involve m & m difficult trips1 until y w ?9k no?+ ( fly+1 = example1 on long raid+ t\rs ov] unfamili> enemy c\ntry4 ,equipm5t4--,kn[+ t y may h to l& f> away f any headqu>t]s1 y mu/ take a complete set ( tools & cov]s = ! airplane4 ,y\r clo?+ ne$ n be diff]5t f usual1 & w comprise helmet1 goggles1 lea!r suit1 & gloves4 ,d n =get y\r h&k]*ief1 :i* y frequ5tly ne$ to clean (f y\r goggles4 ,! in/rum5ts ne$$ on a cross-c\ntry trip are3 a compass1 :i* %\ld be prop]ly adju/$ be=e />t+ & ! v>iation angle not$4 ,a wri/ wat* is necess>y2 ord9>y da%bo>d clocks g wrong on acc\nt ( ! vibration4 ,take an an]oid b>omet] ) adju/able height read+4 ,( c\rse y w dep5d ^u a revolution indicator1 = no matt] h[ exp]i5c$ a pilot may be 9 8li/5+ out0 faulty eng9e op]ation1 aft] a long flight 8 e> loses its acut5ess1 & he w fall back on ! revolution indicator = assi/ance4 ,! air-spe$ met]1 :e!r ( ! ,pitot type or pressure-plate type1 w prove invaluable 9 fly+ ?r\gh cl\ds or mi/ :5 ! gr\nd is obscur$4 ,also ! incl9omet] is able to give ! angle ( flight :5 ! e>? is n visible1 al?\gh ! spe$ indicator usually is suffici5t to give ! angle ( flight1 = an increase ( spe$ means d[nw>d motion & decrease ( spe$ means upw>d motion4 ,additional in/rum5ts may be us$4 ,map4--,! map is ess5tial = cross-c\ntry "w4 ,x %\ld be tack$ on to ! map bo>d if ! flight is %ort1 b made to run on roll]s if ! flight is long4 ,9 ! latt] case ! map is 9 ! =m ( a s+le long /rip1 :ile y\r flight may be full ( angles2 !re=e y w h to practice us+ ?is sort ( map1 9 :i* ! corn]s ( y\r flight are all drawn z /raight l9es4 ,! scale ( maps may be #b or #d miles to ! in* = long flights4 ,?is scale is sometimes spok5 ( z a fractional figure2 t is1 #b miles to ! in* is ! same z #a_/abg1jjj scale4 ,! map %\ld be /udi$ mo/ c>efully be=e ! />t ( ! trip4 ,! c\rse :i* y propose to fly %\ld be m>k$ out on x2 all available l&m>ks :i* c\ld be ( s]vice z guides %\ld be di/9ctly notic$ & m>k$ on ! map :]e necess>y4 ,^! l&m>ks w 9 case !re is no w9d enable y to make y\r trip )\t us+ ! compass at all1 & 9 case ( w9d1 are ess5tial z a *eck on ! compass4 ,m>k (f ! di/ance 9 miles betwe5 consecutive po9ts ( y\r c\rse4 ,m>k ! compass be>+ ( ea* leg ( ?is c\rse4 ,z l&m>ks t[ns are ! be/ guides1 & !y %\ld be und]scor$ on ! map1 or enclos$ 9 circles4 ,x is cu/om>y n to fly actually ov] t[ns4 ,railways are v good assi/ance to f9d+ y\r way1 & ^! %\ld be m>k$ on ! map 9 black :]ev] !y approa* )9 #aj miles ( ! c\rse4 ,m>k wat] c\rses ) blue color1 & roads ) r$4 ,l&m>ks4--,only practice c make a pilot good at obs]v+ ! v>i\s features ( ! gr\nd b5ea? him4 ,! v>i\s features :i* c be us$ z guides are ^? :i* are mo/ visible4 ,aft] t[ns1 railways come next 9 importance4 ,_! bridges1 tunnels1 etc41 make good l&m>ks4 ,on w9dy days :5 rely+ on ! compass1 x w be well to keep 9 sight ( a railway ev5 if ?is be ! long] way ar\nd1 because ! railway gives a con/ant *eck ^u ! compass be>+4 ,9 ?is case y w h not$ on y\r map a g5]al magnetic be>+ ( ! railway1 :i* be>+ y c readily comp>e ) y\r compass read+4 ,moreov]1 ! railway is good 9 case y become involv$ 9 a fog or mi/ = a "t4 ,x %\ld be rememb]$1 h[ev]1 t on mo/ ( ! maps no di/9ction is made betwe5 "o & two-track roads2 also t x is easy to make mi/akes :]e bran* l9es are n %[n on ! map because !y are dead ends lead+ to private qu>ries1 etc41 & may be tak5 = junctions4 ,railways sometimes seem to end abruptly1 :i* means t y are look+ at a tunnel4 ,wat] is visible f a great di/ance4 ,cautions to be obs]v$ are t aft] a heavy ra9 small flood$ /reams may take on ! appe>ance ( l>g] bodies ( wat] or lakes1 :i* y w h difficulty 9 reconcil+ ) ! map4 ,small riv]s are (t5 ov]hung ) foliage1 & to foll[ !m 9 all _! curves w wa/e a lot ( "t4 ,! use ( roads z guides may be gov]n$ by ! fact t pav$ roads are usually ma9 roads1 & telegraph wires may be expect$ along !m4 ,9 ! new] p>ts ( ! ,unit$ ,/ates ! sy/em ( lay+ out roads provides a v useful means ( gag+ di/ances2 ,i ref] to ! section sy/em :i* is 9 use1 = in/ance1 9 ,ill9ois1 :]e !re is a road e mile runn+ nor? & s\?1 s t ! entire c\ntry is cut up into squ>es #a mile on ea* side1 ) occasional roads ( c\rse at -mile & -mile po9ts4 ,navigation by ,l&m>ks4--,9 all cases ( cross-c\ntry fly+ ! pilot w h two indep5d5t sy/ems ( ma9ta9+ 8 prop] directions3 fir/1 ! comput$ compass be>+2 second1 ! use ( l&m>ks ^: position is kn[n4 ,9 comp>+ 8 comput$ c\rse ) ! c\rse actually indicat$ by pass+ ov] ^! l&m>ks ! rule %\ld be made t1 9 case ( d\bt :5 a l&m>k is n di/9ctly recogniz$1 take ! compass c\rse2 !re are _m *ances t a l&m>k may be alt]$ or ev5 remov$ )\t be+ s record$ on ! pilot's map1 :]eas ! errors ( ! compass ( c\rse are presumably und]/ood by ! pilot :o has secur$ e opportunity to *eck x :5 pass+ previ\s l&m>ks4 ,x is important to note ! "t ( complet+ successive /ages ( ! flight1 t is :5 pass+ ov] pr$et]m9$ l&m>ks4 ,"t is a v unc]ta9 condition to asc]ta9 9 airplane fly+ = x seems to pass quickly on calm days b sl[ly :5 ! j\rney is r\gh4 ,if ! pilot does n *eck ! "t int]val betwe5 successive objects he is q likely to expect ! next be=e x is really due4 ,l&+ ,fields4--,next to ! ev]-pres5t worry :i* ! pilot has reg>d+ ! p]fect op]ation ( 8 eng9e1 ! mo/ important ?+ ab\t cross-c\ntry fly+ is t :]ev] he may be he mu/ h available a l&+ field )9 glid+ di/ance 9 case 8 eng9e defaults4 ,! "q is ( c\rse imm$iately rais$1 8,:at if !re is no l&+ field )9 glid+ range80 ,! answ] to ?is is t ! pilot w in/9ctively le>n to keep 8 eyes op5 = l&+ possibilities e m9ute ( 8 progress :e!r he expects to use !m or n2 9 cross-c\ntry fly+ ! look\t = fields is fir/ & =emo/ 9 8 m9d2 if !re are no fields1 x is up to him to pick out a spot ( gr\nd :i* is ! lea/ objectionable = a l&+4 ,9 ! ,/ate ( ,ill9ois ! "q ( l&+ fields is almo/ non-exi/5t1 because !re are l>ge1 flat fields & pa/ures 9 almo/ e squ>e mile ( ! f>m+ di/rict1 & a cross-c\ntry flight f ,rant\l to ,*icago c\ld h no t]rors = ! beg9n] z reg>ds ! *oice ( a l&+ gr\nd4 ,:5 x comes to a cross-c\ntry flight l ,ru? ,law's1 f ,*icago to ,new ,york1 ^! favorable conditions beg9 to disappe> aft] ! middle ( ! j\rney1 t is1 ea/ ( ,buffalo4 ,! mo/ ideal condition = cross-c\ntry fly+ w\ld be "o l t on ! ,london-,ed9burgh r\te1 :]e l&+ gr\nds are s frequ5t t by fly+ at a height ( a c\ple ( miles ! pilot c free 8 m9d completely ( ! worry ( suitable l&+ places2 b 9 ! ,unit$ ,/ates we h v few e/abli%$ airdromes1 & ! only approa* to ! ,london-,ed9burgh r\te is ! ,/4 ,l\is-,new ,york r\te1 :]e ! jumps are approximately #aej miles2 namely1 ,/4 ,l\is1 ,*ampaign1 ,indianapolis1 ,dayton1 ,s&usky1 ,erie1 ,hammondsport1 ,philadelphia1 & ,new ,york4 ,t is :y long cross-c\ntry trips are su* an adv5ture 9 ?is c\ntry & su* an ord9>y affair 9 ,engl&4 ,! beg9n] w h special difficulty 9 tra9+ 8 m9d to pick out available l&+ places2 fir/ ( all because ! e>? looks s diff]5t f ! sky t x is only ) practice a beg9n] le>ns ! %ades & hues ( color :i* mean c]ta9 k9ds ( gr\nd1 or le>ns to spot ! diff]5t features ( flat & hilly c\ntry4 ,ev5 = an accompli%$ pilot x is h>d to tell :e!r a field is good or bad f a height ( ov] #ajjj ft42 & z x is dang]\s to fly ?is l[ ov] unkn[n t]ritory1 y c at once see :at is meant by ! worry ( scann+ ! c\ntryside = available fields4 ,*oose ! be/ field t y c get1 hav+ a smoo? surface & be+ easy to get out ( 9 all directions4 ,! foll[+ consid]ations are int5d$ z a guide to :at con/itute ! be/ field1 9 case y h a *oice betwe5 sev]al possibilities4 #a4 ,*oose a field ne> a t[n if possible1 or fail+ t1 ne> a ma9 road or at lea/ a good road4 ,rememb] t a field :i* appe>s to be ne> a t[n f ! air may actually turn out to be a long walk aft] y h l&$ !re & f9d t !re are v>i\s trips to be made to & fro betwe5 y\r *os5 l&+ spot & ! t[n = ! purpose ( secur+ ropes1 gasol9e1 supplies1 etc4 ,if y l& ne> a ma9 road !re w probably be telegraph wires along x1 :i* are undesirable 9 ! case ( a small field & w9d direction su* t y h to rise (f ! field ov] ! telegraph wires4 ,x is (t5 h>d to di/+ui% betwe5 ma9 roads & m9or roads1 & x w be wise to look = ! numb] ( vehicles on any road 9 det]m9+ :e!r or n x is ! ma9 road4 #b4 ,! be/ field is a /ubble field1 & is mo/ num]\s ( c\rse 9 ! fall :5 ! crops are 94 ,x w h a lighti% br[n color :5 se5 f a height1 & is pretty sure to be smoo?1 )\t dit*es or m\nds4 ,grass l& is next be/1 b is (t5 full ( m\nds4 ,pl[$1 furr[ fields are to be avoid$4 ,x might be said t /ubble fields w be h>d to get out ( aft] a wet night4 ,vegetable & corn fields h a d>k gre5 appe>ance :i* ! pilot mu/ le>n to di/+ui% f grass pa/ures1 etc4 ,if y *oose pa/ure l&1 rememb] t 9 summ] ev5+s ! f>m animals w g5]ally be ly+ d[n ne> ! h$ges4 #c4 ,avoid riv] valleys = l&+ ov] night1 z !re is liable to be a fog 9 ! morn+4 #d4 ,any field :i* has be5 previ\sly us$ = l&+ ) success by an army (fic] c be wisely *os54 ,! f9al det]m9ation ( l&+ field *>act]i/ics c be made :5 y\r airplane has desc5d$ to a height ( #ajjj ft4 (f ! gr\nd1 & 9 case y are n mak+ a =c$ l&+ & y\r eng9e is /ill go+1 y c *eck up y\r e/imate by desc5d+ to ?is level4 ,prop] ,dim5sions ( ,fields & ,airdromes4--,!re are ?ree k9ds ( fly+ fields4 ,"o is ! airdrome :i* is us$ exclusively = fly+1 & may be z l>ge z a mile squ>e2 v few ( ^! w be f\nd 9 cross-c\ntry flights 9 ! ,unit$ ,/ates4 ,second1 !re is :at is call$ ! 8"o-way0 field1 a long1 n>r[1 op5 space :i* is usable :5 ! w9d bl[s p>allel to its l5g?4 ,?ird1 !re is ! 8two-way0 field1 :i* has two suffici5tly long runways at "r angles to ea* o!r4 ,a two-way field is v mu* bett] ?an a "o-way field1 inasmu* z y c always head )9 #de ( ! w9d1 :]eas 9 a "o-way field an extreme case w\ld be #ij4 ,moreov]1 two-way fields1 su* z ! cresc5t-%ap$ field at ,dayton1 ,ohio1 sometimes p]mit ( almo/ univ]sal direction ( flight4 ,! two-way field may be cresc5t-%ap$1 ,t-%ap$1 or ,l-%ap$4 ,an ,l-%ap$ field %\ld h ea* arm #bjj by #cjj yd4 ,"u c]ta9 conditions !re may be build+s locat$ inside or outside ! angle :i* d no h>m aside f creat+ eddies 9 case ( /rong w9d4 ,a ,t-%ap$ field %\ld also h its arms #cjj by #bjj yd4 9 size4 ,reg>d+ ! size ( fields x c be said t1 :ile ! ,,jn-#d ma*9e w rise (f ! gr\nd aft] a run ( #ajj yd4 or s1 a field ( ?is l5g? is ( c\rse n big en\gh = frequ5t use1 especially if bord]$ by trees1 telegraph l9es1 f5ces1 & s =?4 ,a field = tempor>y use %\ld be at lea/ #bjj by #bjj yd41 ab\t #i acres4 ,if ob/ructions at ! edges are m ?an #e ft4 high add to ?is #bjj yd4 a di/ance equal to twelve times ! height ( ! ob/ruction4 ,= a p]man5t field #cjj yd4 is ! m9imum dim5sion necess>y = cle>+ ob/acles & mu/ be increas$ if ! trees exce$ #ej ft4 9 height4 ,?is m9imum dim5sion assumes h>d gr\nd & ! possibility ( />t+ 9 any direction4 ,tra9+ fields are mile squ>e or m4 ,:atev] field is us$ ei!r tempor>ily or p]man5tly by ! pilot %\ld be absolutely famili> to him ov] e in* ( its surface4 ,! adjac5t c\ntry %\ld also be absolutely famili> to him f ! /&po9t ( possible =c$ l&+s :i* he may h to make dur+ 8 flight2 he %\ld make a habit ( in=m+ himself z to all ! woods & hills1 etc41 :i* c affect air curr5ts 9 ! neighborhood ( ! field f :i* he is go+ to />t4 ,guide ,po/s on ,airdromes4--,"s fields h pot holes 9 !m1 & ^! holes %\ld be m>k$ 9 ea* case ) a l>ge high r$ or yell[ flag4 ,d n use %ort1 small flags1 z !y w frequ5tly be invisible to pilots taxy+ on ! gr\nd4 ,all telephone wires1 etc41 %\ld h l>ge blankets or o!r suitable signals hung ov] !m to w>n ! pilot away4 ,commonly accept$ m>ks = designat+ a l&+ spot on airdromes are z foll[s3 ,= day use a l>ge lett] 8,t0 ly+ on ! gr\nd1 made out ( :ite clo? /rips #ae by #c ft4 ,?is lett] ,t is %ift$ ) ! w9d s t its long leg always po9ts 9 ! direction ( ! w9d & ! pilot w !re=e h no?+ to d 9 l&+ b approa* ! lett] 8,t0 f ! bottom1 s to speak4 ,= night fly+ a sy/em ( f\r fl>es is us$1 s arrang$ t ! pilot 9 mak+ a prop] l&+ w pass fl>e ,a on 8 left2 )9 #ej yd4 fur!r on1 fl>e ,b2 !n #ajj yd4 fur!r on1 fl>e ,c1 also on 8 left4 ,9 pass+ fl>e ,c he w h a f\r? fl>e1 ,d1 #ej yd4 to 8 "r4 ,t is to say1 ! f\r fl>es make ! outl9e ( a lett] 8,l0 & ! pilot approa*es ! lett] hav+ ! long leg on 8 left4 ,! fl>es may be made by putt+ half a gallon ( gasol9e into a pail4 ,?is w burn = #cj m94 & w be visible #h miles away4 ,sometimes at night in/ead ( fl>es :ite %eets c be spread on ! gr\nd & a %ad$ lamp us$ to illum9ate ! %eets4 ,all se>*lights on ! l&+ field %\ld po9t 9 ! direction ( l&+4 ,all o!r lights )9 a di/ance ( a mile %\ld be ext+ui%$1 & r$ lamps %\ld be us$ at dang] po9ts4 ,on moonlight nights ! same signals & guides may be us$ z 9 ! daytime4 ,pegg+ ,d[n an ,airplane4--,9 l&+ = ! night d n /ay up until x gets d>k b *oose a l&+ place :i* w all[ y to come d[n #a hr4 be=e d>k2 ?is am\nt ( "t w be ne$$ = lay+ up ! ma*9e ov] night4 ,z y come to ! l&+ gr\nd note ! "t s t y c compute ! actual duration ( y\r flight 9 y\r report1 !n make a good l&+4 ,taxy ! ma*9e to ! spot :]e y int5d to leave x ov] night1 su* z ! lee ( a h$ge1 etc42 or if !re is no *oice ( position taxy ! ma*9e to ! approximate location f :i* y w make y\r />t next morn+2 ?is w save tr\ble :5 y get ready to />t4 ,dism\nt f y\r ma*9e1 lift up ! tail en\gh to leave ! w+s edgewise to ! w9d1 ! ma*9e1 ( c\rse1 fac+ ! w9d1 & jack up ! tail 9 ?is position by ! use ( any conv5i5t prop4 ,la% ! control :eel or joy /ick fa/ 9 a fix$ position s t ! w9d c n flap ! control surfaces ar\nd & damage !m4 ,*oose a sunk5 tr5* if possible 9 :i* ! :eels may be sunk2 if ! w9d is go+ to bl[ & !re is no sunk5 tr5* x w be wise to dig "o s t ! effect ( ! w9d on ! airplane w be less5$4 ,if ! tr5* is n necess>y1 at lea/ put *ocks "u ! :eels4 ,peg d[n ! w+s & ! tail to /akes driv5 into ! gr\nd us+ rope if y c get "s or lack+ ?is 9 an em]g5cy f5ce wires :i* y c secure by means ( y\r wire cutt]s4 ,d n la% tightly en\gh to induce /ra9s 9 ! framework ( ! ma*9e4 ,next1 fill up ! tanks if a supply ( gasol9e or oil is available4 ,put ! cov]s on ! propell]s1 eng9e1 c[ls1 etc41 9 ord] t ra9 & dew %all d no damage to ^! p>ts4 ,! w+s & body are v>ni%$ wat]pro( & w n be s]i\sly damag$ by a little moi/ure2 to avoid ! collection ( moi/ure 9 ! w+s small eyelet holes are sometimes set 9 ! w+s at ! trail+ edge to let out ! wat]4 ,( c\rse1 y w engage a gu>d to wat* ! ma*9e all night2 see t a rope is /rung ar\nd ! airplane to keep (f ! cr[d :i* may collect4 ,,a]ial ,,navigation ,effect ( ,w9d4--,navigat+ 9 an airplane is complicat$ only on acc\nt ( ! fact t !re is a w9d bl[+ :i* may n be 9 ! desir$ direction4 ,:ile on ! sea navigation is simple ?r\gh ! assi/ance ( ! magnetic compass 7because side w9ds c n mat]ially drift ! %ip sideways71 9 ! air ?is is n ! case2 = if ! pilot us+ ! compass po9ts ! nose ( ! airplane directly nor? :ile a we/ w9d is bl[+1 ?is w9d w cause ! ma*9e to drift 9 an ea/]ly direction s t 9 an h\r ( flight ! airplane w be (f its c\rse by an am\nt equal to di/ance :i* ! w9d travels 9 #a hr42 & ! jo9t result ( ! motion ( ! airplane =w>d & ! motion ( ! w9d sideways w cause ! ma*9e to drift 9 a nor!a/]ly direction at a spe$ q diff]5t f its rat$ velocity1 & 9 ?is case some:at l>g]4 ,victor ,c>l/rom 9 8 ,*icago-,new ,york flight f\nd :ile he 0 ov] ,clevel& t a side w9d 0 deviat+ 8 c\rse #ag away f :at x %\ld be1 & if he _h n _h su* l&m>ks z ! %ore ( ,lake ,erie = guidance he might easily h lo/ consid]able "t4 ,! "q ( mak+ all[ance = ?is w9d drift is v important :]e !re are no l&m>ks1 z 9 ! case ( night fly+1 fly+ ov] ! sea1 or fly+ ov] ! cl\ds2 & ! only way ! pilot c make all[ances = ^! conditions is to figure !m out be=e he />ts f ! airdrome1 & plan to circumv5t !m4 ,t is to say1 ! pilot 9 flight has no means1 aside f visual obs]vation ( ! gr\nd1 to det]m9e :e!r or n ! w9d is bl[+ him (f 8 c\rse4 ,he mu/ det]m9e ! :ole situation be=e he />ts1 & ! process ( do+ s is z foll[s4 ,graphical ,me?od = ,det]m9+ ,direction to ,/e]4--,! pilot w asc]ta9 f ! wea!r vane & anemomet] ( ! airdrome 7#a7 ! velocity & 7#b7 ! direction ( ! w9d1 7#c7 ! spe$ ( ! airplane he is to fly1 7#d7 ! compass be>+ ( ! actual c\rse :i* he desires to foll[4 ,) ?is data x is possible to con/ruct a simple diagram & to det]m9e ! direction to be /e]$ & ! actual velocity :i* w result 9 ! propos$ j\rney4 ,a draftsman's scale1 protractor & divid]s1 a p5cil & a piece ( pap] are ! necess>y equipm5t4 ,:5 ! w9d bl[s at an angle ) ! desir$ c\rse x is necess>y to /e] ! airplane 9 su* a direction t its own =w>d motion w neutraliz] ! side effect ( ! drift ( ! w9d f mom5t to mom5t4 ,! problem is to det]m9e ?is direction = /e]+1 z x is n kn[n4 ,we are n conc]n$ ) di/ances 9 ?is problem1 = ! direction is go+ to be ! same :e!r our flight is ( #ajj or #bjj miles4 ,we are1 h[ev]1 vitally conc]n$ ) velocities2 & we w assume t ! velocity ( ! airplane is kn[n to be #ge miles p] h\r1 & f obs]vation on a local anemomet] ! velocity ( ! w9d is kn[n to be #bj miles an h\r4 ,we also "k1 ( c\rse1 ! direction ( ! w9d1 :i* %\ld be giv5 9 t]ms ( an angle ^: o!r leg po9ts directly nor?4 ,n[ if ! flight is to be made at a height ( #bjjj ft41 z is usual 9 cross-c\ntry flight ov] av]age c\ntry1 we w f9d t ! spe$ ( w9d w increase z we rise up2 moreov]1 t its direction w *ange4 ,9 ! pres5t case ! w9d w be #hh p] c5t4 high] 9 #bjjj ft4 ?an x is on ! gr\nd2 t is to say1 ! velocity at ! altitude we are go+ to use is tw5ty times #a4hh1 or ab\t #ch miles p] h\r4 ,moreov]1 z ! height increases ! direction ( ! w9d *anges1 %ift+ ar\nd always 9 a clockwise direction z ! height increases1 9 ! pres5t case %ift+ ar\nd #af f its gr\nd direction4 7,! *ange ( velocity & direction = v>i\s heights is indicat$ on ! subjo9$ table47 ,?us a we/ w9d becomes at a height ( #bjjj ft4 a slightly nor?we/ w9d1 or1 to be exact1 bl[s f a direction :i* is #gd we/ ( nor?4 ,our treatm5t ( ! problem !n has = />t+ po9ts3 velocity ( w9d1 #ch miles p] h\r2 direction ( ! w9d1 #gd we/ ( nor?2 velocity ( airplane #ge miles p] h\r2 desir$ direction ( flight 7:i* has be5 det]m9$ by lay+ out on ! map & read+ ! compass be>+ ) ! protractor71 say #fj ea/ ( nor?4 ,9 #a hr4 ( flight ! ma*9e w\ld travel 9 ?is unkn[n direction a di/ance ( #ge miles 7 x n = ! w9d1 b = e h\r ( su* fly+ ! w9d is bl[+ x #ch miles sideways2 & ! desir$ direction mu/ be su* t its jo9t effect1 toge!r ) ! #ch mile sideways w9d1 w leave ! ma*9e exactly on its prop] c\rse at ! end ( ! h\r4 ,on ! map or piece ( pap] d5ote ! />t+ po9t by ,a 7see ,fig4 #cg74 ,f ,a draw a l9e p>allel to ! w9d 7t is to say1 #gd we/ ( nor?71 & let ?is l9e repres5t1 to any conv5i5t scale1 ! spe$ ( ! w9d1 #ch miles p] h\r4 ,! f> end ( ! l9e may be call$ ,b1 & may be giv5 an arr[ to repres5t ! direction ( w9d4 ,n[ draw on ! map a l9e f ,a to ! desir$ de/9ation 7,c71 giv+ x1 ( c\rse ! prop] compass be>+4 ,take ! divid]s1 & ) ,b z a c5t]1 describe an arc at su* di/ance z to repres5t #ge miles p] h\r1 ! spe$ ( ! ma*9e2 ?is arc w int]cept ! l9e ,,ac at ,d1 & ,,bd !n gives ! direction to /e]1 = x is t direction :i* w p]mit ! airplane 9 #a h\r exactly to neutralize ! sidewise drift ( ! w9d4 ,! di/ance ,,ad on ?is diagram c be measur$ (f & w give ! actual velocity ( movem5t along ! l9e ( flight 9 miles p] h\r4 ,notice t x is #ig miles p] h\r1 q diff]5t f ! spe$ ( ! airplane4 ,illu/ration3 ,,fig4 #cg4--;,graphical me?od = det]m9+ direction to /e] to c\nt]act w9d-drift4 ,assum+ t ! pilot has det]m9$ ! prop] angle t[>d :i* ! airplane nose mu/ be po9t$1 has ma9ta9$ ?is angle ?r\gh\t 8 flight by means ( ! compass & has safely rea*$ 8 objective2 = ! return trip ?is diagram mu/ be completely recon/ruct$ 7unless ! w9d is exactly p>allel to 8 c\rse74 ,! pilot %\ld n make ! mi/ake 9 return+ to ! />t+ po9t ( /e]+ ! airplane nose 9 a direction exactly opposite to ! outw>d trip2 ! read] may make ?is cle> to himself by draw+ ! return diagram & comp>+ x ) ! outw>d-b\nd diagram4 ,to summ>ize fly+ :5 a cross w9d is bl[+1 x w be said t ! direction ( actual travel w n be ! direction indicat$ by ! axis ( ! airplane2 & t !re=e :ile 9 a picture ( ! situation ! airplane appe>s to skid sideways along ! :ole c\rse x mu/ be borne 9 m9d t actually !re is no skidd+ :atev] b ! air is meet+ ! airplane 9 normal mann]4 ,! situation is analog\s to t ( a fly go+ f "o side to ! o!r ( ! cab9 ( a mov+ %ip1 :]e ! actual c\rse ?r\gh space ( ! fly is an app>5t skid1 due to ! resultant ( its own & ! %ip's movem5t4 ,,v>iation ,,( ,,velocity ,,& ,,direction ,,) ,,height 7#be miles p] h\r w9d7 ---------------------------------------- ---------------------------------------- ---------------------------------------- ,height 9 feet ,at surface #ejj #ajjj #bjjj #cjjj #djjj #ejjj ---------------------------------------- ---------------------------------------- ---------------------------------------- ,velocity *ange 9 p] c5t #ajj #ace #agb #ahh #aif #bjj #bjj ---------------------------------------- ---------------------------------------- ---------------------------------------- ,clockwise deviation 9 degrees #j #e #aj #af #ai #bj #ba ---------------------------------------- ---------------------------------------- ---------------------------------------- ,effect ( ,w9d on ,radius ( ,action4--,n only is ! direction ( flight alt]$ by ! w9d b also ! radius ( action f a /&po9t ( gasol9e capacity is alt]$4 ,9 ! above ma*9e ! gasol9e capacity is suffici5t = #c hr4 ( flight4 ,h[ f> c x g across c\ntry & return be=e ! gasol9e is us$ up8 ,always all[ hr4 gasol9e = climb+ & = m>g92 ?is leaves #c hr41 :i* at #ge miles an h\r is #bbe miles1 or #aab miles out & #aab miles back4 ,n[ suppose t a flight is to be made across c\ntry directly 9 ! tee? ( a #dj-mile w9d2 ! radius ( flight w be alt]$ z indicat$ by ! foll[+ calculation3 ,spe$ outw>d is obvi\sly #ge m9us #dj or #ce miles p] h\r4 ,spe$ on ! return trip is obvi\sly #ge plus #dj or #aae miles p] h\r--#c4bi times z fa/--& occupy+ a "t :i* may be designat$ by ! lett] x4 ,! "t on ! outw>d trip may be designat$ by #c4bix1 a total "t ( x #c4bix :i* we "k equals #ahj m94 be=e ! gas runs out4 ,solve ! equation x #c4bix #ahj & we f9d t x is equal to #db m941 t is1 ! return trip requires #db m941 & ! outw>d trip requires #ach m94 ,! di/ance cov]$ on ! outw>d trip is !n #ach_/fj ( #ce1 :i* equals #hj4e miles4 ,! radius is !n r$uc$ f #aab miles to #hj4e miles4 ,9 cases :]e ! w9d is n p>allel to ! l9e ( flight ! actual velocity ( c\rse c n be obta9$ by add+ up ! airplane & w9d velocities1 b mu/ be obta9$ by ! graphical me?od m5tion$ above2 !nce=w>d ! calculation is ! same4 ,effect ( ,height4--,( c\rse if "o has to fly 9 ! tee? ( a w9d & c *oose "o's own altitude1 x is desirable to fly l[ :]e ! head w9d has its small] velocity1 & :5 fly+ ) ! foll[+ w9d to rise to consid]able altitudes4 ,! prop] height at :i* to fly w be ab\t #aejj to #cjjj ft41 = cross-c\ntry trips ov] ord9>y c\ntry2 b may be increas$ :5 ! w9d is un/eady or decreas$ :5 !re are l[-ly+ cl\ds4 ,! /ead9ess z well z ! spe$ ( ! w9d increases ) ! height4 ,! "* ( ! c\ntry %\ld be c>efully inve/igat$ f ! pr(ile maps be=e />t+2 all hilly p>ts %\ld be m>k$ on ! map z a w>n+ aga9/ l&+4 ,cont\r is n readily di/+ui%$ f a height ( #bjjj ft4 & = ?is reason po9ts may be indicat$ on ! map :]e poor l&+ places make x desirable to fly high4 ,! "* ( ! c\ntry or ! sc>city ( l&+ places may make x advisable to fly at high altitudes = ! foll[+ reasons3 7#a7 9 case ( eng9e failure a good m>g9 ( height is necess>y to provide l5g? ( glide to rea* di/ant l&+ places2 7#b7 !re is !n pl5ty ( space = right+ ! airplane 9 case ( bumps1 side slips1 etc42 7#c7 eddies or local curr5ts due to inequalities ( ! gr\nd d n exi/ to great heights2 7#d7 l&m>ks c be bett] di/+ui%$ f high altitudes because ! vision is bett] 7h[ev]1 "o mu/ nev] tru/ to l&m>ks only 9 navigat+ b %\ld con/antly use a compass if only z a *eck1 & especially 9 pass+ ?r\gh cl\ds74 ,hav+ select$ 9 advance ! prop] height to use dur+ ! trip climb to ?is height 9 circles2 note ! direction ( w9d drift mean:ile to *eck up y\r e/imate4 ,pass directly ov] ! po9t ( dep>ture & :5 ov] x po9t ! nose ( ! airplane = a mom5t directly t[>d ! desir$ objective 7:i* c be done ) ! aid ( ! magnetic compass72 select "s di/ant object :i* is dead ahead1 & !re=e directly 9 ! c\rse2 !n head ! nose ( ! ma*9e up into ! w9d j en\gh s t ! direction ( movem5t w be /raight t[>d ?is di/ant object4 ,! direction ( ! nose ( ! ma*9e ?us set by a me?od di/9ct f ! graphical me?od above m5tion$ %\ld exactly correspond1 h[ev]1 ) ! calculat$ direction2 & ?us a means ( *eck+ is obta9$4 ,effect ( ,fog4--,! effect ( fog ^u navigat+ an airplane is t x prev5ts ! use ( l&m>ks 9 aid+ ! pilot2 also t x upsets ! pilot's s5se ( level4 ,^! two effects are1 ( c\rse1 indep5d5t ( ! fact t prop] l&+ places are obscur$1 ) resultant p]il 9 case ( eng9e failure4 ,!re=e1 a fog %\ld be avoid$ :5ev] possible2 :5 "o comes up1 ! airplane %\ld desc5d1 & %\ld nev] attempt to get above x1 z 9 c]ta9 localities x may turn out to be a gr\nd fog4 ,if ! fog is v bad1 l& at ! e>lie/ opportunity4 ,x is on acc\nt ( fog t ! pilot avoids riv] valleys :]e frequ5tly !re is a haze f ! gr\nd up to a height ( #gjj ft41 prev5t+ ! view ( prop] l&+ places 9 case ( necessity4 ,effect ( ,cl\ds on ,navigation4--,fly+ 9 or above ! cl\ds is a simil> case1 inasmu* z l&m>ks c n be se54 ,x is n wise to g above ! cl\ds :5 on ! sea coa/1 z (f%ore w9ds may1 unkn[n to ! pilot1 c>ry him out to sea2 & any flight ov] ! sea :i* is to a di/ance great] ?an ! safe return glid+ di/ance is1 ( c\rse1 p]il\s4 ,navigation by ,means ( ! ,drift ,indicator4--,! drift indicator is an in/rum5t = det]m9+ directly ! side drift ( an airplane4 ,x enables ! pilot by look+ ?r\gh a telescope at ! gr\nd to det]m9e exactly :at 8 direction ( motion is ) relation to ! gr\nd4 ,! telescope is m\nt$ v]tically & is rotatable ab\t its own axis2 x has a cross-hair :i* appe>s 9 ! field ( view dur+ ! pilot's obs]vation ( ! gr\nd4 ,z ! airplane spe$s ov]head objects on ! gr\nd w appe> ?r\gh ! telescope to slip backw>d 9 ! giv5 direction2 & :5 accu/om$ to ! use ( ?is in/rum5t ! pilot c rotate ! telescope until ! cross-hair is exactly p>allel to ! app>5t l9e ( motion ( objects on ! gr\nd4 ,! telescope cross-hair is p>allel to ! axis ( ! airplane normally & ! scale atta*$ to ! telescope w 9 ?is case read z]o4 ,:5 ! pilot rotates ! telescope s t ! cross-hair becomes p>allel to ! relative backw>d motion ( ! gr\nd ! scale w read some?+ diff]5t f z]o & w give ! angle betwe5 ! actual l9e ( motion & ! axis ( ! airplane4 ,su* a drift indicator is1 ( c\rse1 useful only :5 ! gr\nd is visible4 ,! pilot kn[+ ! angle betwe5 ! airplane axis & ! l9e ( motion & !re=e kn[+ ! deviation betwe5 ! suppos$ c\rse & ! actual c\rse is able to make corrections & /e] ! ma*9e 9 its prop] direction4 ,?is may be done by alt]+ ! 8lubb]-l9e0 or 8 compass j en\gh to (fset ! side drift ( ! ma*9e2 aft] :i* ! desir$ c\rse may be foll[$ by simply keep+ to ! prop] compass be>+4 ,an in/rum5t has be5 devis$ :]e9 ! rotation ( ! drift-indicator telescope simultane\sly alt]s ! lubb]-l9e z]o4 ,! op]ator !n has m]ely to take an occasional obs]vation ( ! app>5t drift l9e ( ! gr\nd1 :i* obs]vation automatically %ifts ! lubb]-l9e & navigation proce$s z if !re 7 no side w9d bl[+ :atev]4 ,kn[+ ! angle betwe5 ! direction ( movem5t & ! airplane axis1 ! pilot may !n compute ! spe$ ( motion 9 a mann] analog\s to ! graphical me?od previ\sly m5tion$2 or he c make use ( a *>t = ! det]m9ation ( ?is spe$4 ,navigation ov] ,wat]4--,9 fly+ ov] wat] ! pres5ce ( waves is a valuable guide to ! aviator1 = he kn[s t ^! waves ext5d 9 a direction normal to ! w9d4 ,moreov]1 he kn[s t ! velocity ( ! waves be>s "s relation to ! velocity ( ! w9d4 ,9 ord] to e/imate ! velocity ( ! waves x is only necess>y to "k _! wave l5g?1 t is1 ! di/ance betwe5 two consecutive wave cre/s4 ,! rule is t = a wave l5g? ( #aj ft4 ! velocity is #aj miles p] h\r1 & w v>y z ! squ>e root ( ?is wave l5g?2 t is1 if ! wave l5g? is half1 ! velocity w be #aj divid$ by ! squ>e root ( #b1 or #g4a miles p] h\r4 ,,*apt] ,,vi ,,! ,,rigg+ ,,( ,,airplanes ,object4--,! object ( ?is *apt] is to tea* ! elem5t>y pr9ciples ( correct rigg+4 ,x is n expect$ t ! /ud5t w become an exp]t me*anic1 b ) ?is treatm5t z a basis & ?r\gh practice he w be able to judge :e!r or n a ma*9e is correctly & safely rigg$4 ,9 o!r words1 he w n h to dep5d on someone else's judgm5t z to :e!r panels1 wires1 controls1 /ruts1 etc41 ( a ma*9e are 9 good ord]1 b he w be able to obs]ve und]/&+ly t !y are4 ,if ! eng9e goes wrong he c l&1 if ! rigg+ goes wrong he is 9 great difficulty4 ,moreov]1 if ! rigg+ is wrong1 spe$ is less5$ & ! /ability is unc]ta94 ,! fir/ ?+ to be le>n$ 9 rigg+ is a k ( ! peculi> t]ms :i* h come into use 9 a]onautics def9+ diff]5t p>ts ( ! ma*9es4 ,our pres5t li/ ( t]ms is d]iv$1 p>tly f ,fr5*1 p>tly f ,engli%1 & p>tly f ,am]ican t]ms4 ,?us diff]5t names may ref] to ! same "p4 ,,nom5clature #a4 ,tractor4--,an airplane t is pull$ ?r\gh ! air by a propell] situat$ 9 front ( ! ma*9e1 is call$ a tractor4 #b4 ,pu%]4--,if ! propell] is back ( ! ma9 lift+ planes ! ma*9e is call$ a pu%]4 #c4 ,fuselage or ,body4--,! ma9 body ( ! airplane 9 :i* ! pilot sits & to :i* ! l&+ ge>1 motor1 controls1 & su/a9+ surfaces are fix$4 ,a small body1 especially 9 pu%] types ( ma*9es1 is call$ a ,nacelle4 #d4 ,cockpit4--,! op5+s & space 9 ! fuselage :]e pilot or obs]v] sits4 #e4 ,/ream-l9e ,body4--,! %ape ( a body or "p :i* p]mits a regul> fl[ ( air ar\nd & along x ) ! lea/ resi/ance1 9 o!r words ) m9imum1 ob/ruction & eddy+4 #f4 ,fair+4--,build+ up a memb] or "p ( ! plane ) a false piece t x may h a /ream-l9e body4 #g4 ,w+s1 ,planes1 ,panels4--,! ma9 support+ surfaces ( an airplane are call$ w+s1 al?\gh ! t]ms planes & panels are probably z frequ5tly us$ & ev5 pref]r$ by _m4 ,! t]m panel ref]s prop]ly to a section ( ! w+s ) ! includ$ /ruts & wires4 ,! small panel directly above ! body is call$ ! eng9e section panel or ! c5t] panel1 :ile ! panels to ! "r & left ( ! body or fuselage are call$ ! ma9 panels4 ,! ma9 panels are ! "r & left panels z se5 f ! seat4 ,ea* ma9 panel may be subdivid$ into ! inn] w+ bay1 ! out] w+ bay1 & ! ov]hang4 #h4 ,l&+ ,ge>1 ,*assis or ,und]c>riage4--,! :eels & ! /ruts & wires by :i* !y are atta*$ to ! fuselage4 #i4 ,horizontal ,/abiliz] or ,horizontal ,f94--,! horizontal fix$ tail plane4 #aj4 ,v]tical ,/abiliz] or ,v]tical ,f94--,! small v]tical fix$ plane 9 front ( ! rudd]4 #aa4 ,rudd]4--,! h+$ surface us$ to control ! direction ( ! aircraft 9 ! horizontal plane4 ,z ) a boat1 = /e]+ or 8yaw+0 or *ang+ its direction ( travel4 #ab4 ,elevator or ,flap2 ,flipp]s4--,a h+$ horizontal surface = controll+ ! airplane up & d[n1 usually atta*$ to ! fix$ tail plane2 = pit*+ ! ma*9e or 8nos+ up0 & 8nos+ d[n40 #ac4 ,tail or 8,emp5nages40--,a g5]al "n sometimes appli$ to ! tail surfaces ( a ma*9e4 #ad4 ,ma/ or ,cabane4--,! small v]tical /rut on top ( ! upp] plane us$ = brac+ ! ov]hang4 #ae4 ,ail]ons4--,movable auxili>y surfaces us$ = ! control ( roll+ or bank+ motion4 ,o!r def9itions are t !y are = ! lat]al control or = ma9ta9+ equilibrium4 ,:5 !y are a "p ( ! upp] plane !y are sometimes call$ w+ flaps4 #af4 ,l&+ ,wires or ,gr\nd ,wires 7,s+le74--,! s+le wires :i* support ! weight ( ! panels :5 l&+ or on ! gr\nd4 #ag4 ,fly+ ,wires1 or ,load ,wires 7,d\ble74--,! wires :i* support ! body or fuselage f ! planes :5 9 flight4 #ah4 ,drift ,wires4--,! horizontal wires :i* lead f ! nose ( ! fuselage to ! w+s & ?us keep !m f collaps+ backw>d4 ,= ! same reason ! w+s h int]ior drift wires4 #ai4 ,diagonal ,wires4--,any incl9$ brac+ wires4 #bj4 ,skids4--7a7 ,tail ,skid4--,! flexible support "u ! tail ( ! ma*9e4 7b7 ,w+ ,skid4--,! protection "u ! out] edge ( ! l[] w+4 7c7 ,*assis ,skids4--,skids sometimes plac$ 9 front ( ! l&+ ge>4 #ba4 ,horns1 or ,control ,braces4--,! /eel /ruts on ! controls to :i* ! control wires are atta*$4 #bb4 ,/ruts2 ,w+ ,/ruts4--,! v]tical memb]s ( ! w+ trusses ( a biplane1 us$ to take pressure or compression1 :]eas ! wires ( ! trusses are us$ to take pull or t5sion4 ,!re are also fuselage /ruts & *assis /ruts4 #bc4 ,sp> or ,w+ ,b>s4--,! longitud9al memb]s ( ! int]ior w+ framework4 #bd4 ,rib 7,w+74--,! memb]s ( ! int]ior w+ framework transv]se to ! sp>s4 #be4 ,! ,long]ons or ,longitud9als4--,! =e & aft or l5g?wise memb]s ( ! fram+ ( ! fuselage1 usually cont9u\s across a numb] ( po9ts ( support4 #bf4 ,eng9e 7,"r & ,left ,h&74--,9 ! ord9>y tractor ma*9e1 :5 view$ f ! pilot's seat a "r-h&$ eng9e revolves clockwise & "r-h&$4 #bg4 ,propell]4-- #bh4 ,pit* 7,propell]74--,! di/ance =w>d t ! propell] w\ld travel 9 "o revolution1 if !re 7 no slip1 t is1 if x 7 mov+ 9 a ?read cut at ! same incl9ation z ! blade4 ,pit* angle ref]s to ! angle ( incl9ation ( ! propell] blade4 #bi4 ,slip4--,slip is ! diff]5ce betwe5 ! actual travel =w>d ( a screw propell] 9 "o revolution & its pit*4 #cj4 ,dope4--,a g5]al t]m appli$ to ! mat]ial us$ 9 treat+ ! clo? surface ( airplane memb]s to increase /r5g?1 produce tautness1 & act z a fill] to ma9ta9 air & moi/ure tightness4 ,usually ( ! cellulose type4 #ca4 ,controls4--,s9ce !re are ?ree axes or ma9 directions ab\t :i* an airplane may turn or rotate x foll[s t ?ree controll+ devices are requir$4 ,^! are3 7#a7 ! elevator = pit*+2 7#b7 ! rudd] = /e]+ or yaw+2 7#c7 ! ail]ons = lat]al1 roll+ or bank+ control4 ,! t]m controls is a g5]al t]m us$ to di/+ui% ! means provid$ = op]at+ ! devices us$ to control spe$1 direction ( flight & attitude ( ! aircraft4 #cb4 ,cott] ,p9s4--,mu/ be on e nut4 #cc4 ,ca/ell$ ,nuts4--,admit cott] p9s4 #cd4 ,turnbuckles4--,mu/ be well & ev5ly ?read$ & lock$ ) safety wires4 #ce4 ,safety ,wires4--,= lock+ turnbuckles & h+e p9s4 #cf4 ,%ackle & ,p94-- #cg4 ,h+e ,connections4-- #ch4 ,lead+ ,edge or ,ent]+ ,edge4--,! front edge ( a plane4 #ci4 ,trail+ ,edge4--,! re> edge ( a plane4 #dj4 ,/agg]4--,! horizontal di/ance t ! ent]+ edge ( ! upp] w+ ( a biplane is ahead ( ! ent]+ edge ( ! l[] w+4 #da4 ,dih$ral ,angle4--,a t]m us$ to d5ote t ! w+s are arrang$ to incl9e slightly upw>d f ! body t[>d _! tips4 ,! angle made ) ! horizontal by ?is incl9ation ( ! w+ is call$ ! dih$ral angle4 #db4 ,angle ( ,incid5ce4--,! angle at :i* a w+ is incl9$ to ! l9e ( flight4 #dc4 ,decalage4--,diff]5ce 9 angle ( incid5ce betwe5 any two di/9ct a](oils on an airplane4 #dd4 ,*ord4--,di/ance betwe5 ! ent]+ edge & trail+ edge ( a w+ measur$ on a /raight l9e t\*+ front & re> bottom po9ts ( a w+4 #de4 ,camb]4--,! dep? ( ! curve giv5 to a su/a9+ surface su* z a w+4 ,?us x w be obs]v$ t ! planes are n /raight 9 cross-section b are concave slightly upw>d4 ,! dep? ( ?is concavity is ! camb]4 ,ano!r way ( express+ ?is is t camb] is ! greate/ di/ance betwe5 ! surface ( a w+ & its *ord l9e4 #df4 ,gap4--,! di/ance betwe5 ! l[] & upp] w+s ( a biplane4 #dg4 ,spread4--,! di/ance ov] all f "o w+ tip to ! o!r w+ tip4 #dh4 ,a](oil4--,a g5]al "n appli$ to any w+ or lift+ surface ( an airplane4 #di4 ,deadhead ,resi/ance4--,ea* "p ( an airplane aga9/ :i* ! w9d /rikes (f]s a resi/ance aga9/ be+ mov$ ?r\gh ! air4 ,?is is call$ ! deadhead resi/ance or ! p>asite resi/ance4 ,x is = ! purpose ( less5+ ?is resi/ance t ! p>ts ( a ma*9e are /ream-l9$4 ,rememb] t =ce or p[] mu/ be appli$ to ov]come ?is resi/ance & ! less5+ ( su* resi/ance decreases ! p[] necess>y4 ,a p>allel illu/ration is to ?9k ( ! p[] necess>y to pu% a bo>d sideways ?r\gh wat]4 #ej4 ,drift4--,:5 ! air /rikes ! incl9$ w+ ( an airplane its =ce has two compon5ts4 ,"o "p call$ ! lift 7see #eb7 acts up & t5ds to lift ! ma*9e4 ,! o!r "p1 call$ drift1 t5ds to pu% ! ma*9e backw>d4 ,?is drift mu/ also be ov]come by apply+ p[] en\gh to drive ! ma*9e =w>d4 #ea4 ,total ,resi/ance4--,sometimes call$ drag4 7#di7 ,deadhead resi/ance add$ to 7#ej7 drift1 gives ! total =ces oppos+ ! =w>d movem5t ( ! airplane4 ,?is is call$ ! total resi/ance & is ov]come by ! ?ru/ ( ! propell]4 #eb4 ,lift4--7,see #ej74 ,! upw>d or v]tical "p ( ! air pressure act+ aga9/ ! w+s1 & :i* is utiliz$ to lift or support ! airplane4 #ec4 ,c5t] ( ,gravity4--,! po9t ( balance ( an airplane :i* may be o!rwise def9$ z ! po9t ?r\gh :i* ! mass ( an airplane acts4 ,if ! weight is too f> =w>d ! ma*9e is nose-heavy4 ,if ! weight is too f> beh9d ! c5t] ( lift ! ma*9e is tail-heavy4 #ed4 ,aspect ,ratio4--,! ratio ( span to *ord ( a w+ or any o!r a](oil4 #ee4 ,glid+ ,angle 7,volplane74--,! angle made to ! horizontal by ! flight pa? ( an airplane ) ! eng9e %ut (f2 e4g41 an airplane is #ajjj ft4 high1 :5 its eng9e fails4 ,suppose its glid+ angle is #a 9 #f4 ,!re=e1 9 /ill air x c glide #fjjj ft4 =w>d4 ,! g5]al t]m glide ref]s to fly+ )\t p[]4 #ef4 ,! ,angle ( ,be/ ,climb4--,! /eepe/ angle at :i* an airplane c climb4 #eg4 ,/ability4--,! prop]ty ( an airplane to ma9ta9 its direction & to return easily to its equilibrium or balance ) a m9imum ( oscillation4 ,?is is sometimes call$ dynamical /ability4 ,an airplane may h 7fir/7 inh]5t /ability1 :i* is ! /ability due to ! arrangem5t & disposition ( its fix$ p>ts4 ,x may also h /ability ) reg>d to any "o ( ! ?ree directions 9 :i* x may move4 ,^! are nam$ z foll[s3 7#a7 directional /ability1 ) ref]5ce to ! v]tical axis2 7#b7 lat]al /ability ) ref]5ce to ! longitud9al 7or =e & aft7 axis2 7#c7 longitud9al /ability1 /ability ) ref]5ce to ! lat]al 7or ?w>t%ip7 axis4 #eh4 ,fly+ ,position4--,ref]s to ! position ( ! fuselage :5 fly+4 ,) ! ,curtiss ,,jn-#d ma*9es 9 ?is position ! top long]ons are horizontal & level bo? ways4 ,! eng9e be>]s are also level1 & ! w+s h an angle ( incid5ce ( #b4 #ei4 ,capacity4--,! weight an airplane w c>ry 9 excess ( ! dead load 7dead load includes /ructure p[] plant & ess5tial accessories74 #fj4 ,flight ,pa?4--,! pa? ( ! c5t] ( gravity ( an aircraft ) ref]5ce to ! air4 #fa4 ,/all+4--,a t]m describ+ ! condition ( an airplane :i* f any cause has lo/ ! relative spe$ necess>y = support & controll+1 & ref]r+ p>ticul>ly to angles ( incid5ce great] ?an ! critical angle4 #fb4 ,sweepback4--,! horizontal angle 7if any7 t ! lead+ edge ( a ma*9e makes ) ! crosswise or lat]al axis ( an airplane4 #fc4 ,nose ,dive or ,vol-pique4--,a dang]\sly /eep desc5t1 head on4 ,,*apt] ,,vii ,,mat]ials ,,( ,,con/ruction ,! mat]ials ( con/ruction = airplanes %\ld be ( su* mat]ial1 size & =m z to comb9e greate/ /r5g? & lea/ weight4 ,) metal p>ts 9 p>ticul> x may be necess>y to sub/itute less /rong mat]ial = ! sake ( gett+ non-corrosive qualities1 ability to )/& b5d+1 ductility or ease ( b5d+1 etc4 ,) wood1 abs5ce ( w>p+ is important z well4 ,! mat]ials :i* are consid]$ are ! foll[+3 wood1 /eel1 includ+ wires2 special metals z alum9um1 brass1 monel metal1 copp]1 etc41 & also l95 & dope4 ,/r5g? ( ,mat]ials4--,x is important 9 a g5]al way to und]/& ! t]ms us$ 9 speak+ ( /r5g? ( mat]ials4 ,?us we may h /r5g? 9 t5sion1 /r5g? 9 compression1 or /r5g? 9 %e>+1 b5d+ & torsion4 ,"s mat]ial fitt$ to take t5sion w n take compression1 z = example wire2 "s mat]ial1 z bolts1 are suit$ to take %e>1 etc4 ,9 g5]al all mat]ial = airplanes has be5 c>efully te/$ & no excess mat]ial is us$ above t necess>y to give ! ma*9e ! necess>y /r5g?4 ,t5sion4--,?is means ! /r5g? ( a mat]ial :i* enables x to )/& a pull4 ,?us wires are us$ :]e /r5g? ( ?is k9d is requir$4 ,compression4--,?is ref]s to /r5g? aga9/ a pressure4 ,wire has no /r5g? = ?is purpose1 & wood or sometimes /eel is us$4 ,%e>+4--,ref]s to /r5g? aga9/ cutt+ (f sideways4 ,?us ! pull on an eyebolt t5ds to %e> ! eyebolt1 or ! side pull on any bolt or p9 t5ds to %e> ! p94 ,b5d+4--,9 b5d+ mat]ial ! fibres on ! outside t5d to pull ap>t2 ^? on ! inside t5d to g toge!r4 ,?us on ! outside we h t5sion1 & on ! inside compression4 ,along ! c5t] l9e !re is nei!r t5sion or compression1 x is ! 8neutral axis40 ,torsion4--,torsion is a twi/+ =ce1 su* z an eng9e propell] %aft receives4 ,te/+ = ,/r5g?4--,if a wire is an in* squ>e 9 cross-section & breaks :5 a load ( #aej1jjj lb4 is hung on x1 we say t ! /r5g? ( ! wire is #aej1jjj p] squ>e in*4 ,small] wires equally /rong h a /r5g? ( #aej1jjj lb4 p] squ>e in* also1 b !y 9 !mselves w n support a load ( #aej1jjj lb4 b only ! fraction ( t1 accord+ to ! fraction ( a squ>e in* repres5t$ by _! cross-section4 ,9 ! same way1 a squ>e in* ( wood "u a compressive load may break at #ejjj lb4 ,if1 h[ev]1 ! piece ( wood is long 9 proportion to its ?ickness1 x w b5d easily & support mu* less weight4 ,= example1 a p]fectly /raight walk+ cane c\ld p]haps h a ton weight put on x )\t break+ b if ! cane 7 n set squ>ely or if x />t$ to b5d x w\ld imm$iately break "u ! load4 ,^! cases illu/rate ! importance ( hav+ /ruts p]fectly /raight1 n too sp9dl+ & ev5ly b$d$ 9 _! sockets4 ,"s tra9+ ma*9es are built ) a factor ( safety ( #ab4 ,t is to say1 ! break+ /r5g? ( any "p is twelve times ! ord9>y load or /ress "u :i* ! piece is plac$4 ,x %\ld be rememb]$1 h[ev]1 t "u any unusual condition 9 ! air1 su* z bank+1 etc41 extra /ra9s are plac$ on ! p>ts & ! factor ( safety is mu* less ?an #ab4 ,factor ( safety ( #ab ?us does n mean exactly :at x does 9 o!r eng9e]+ "w1 :]e all[ances are made = sev]e conditions4 ,! s-call$ factor ( safety ( #ab 9 airplane "w is probably no great] ?an a factor ( safety ( #b or #c 9 regul> eng9e]+ "w4 ,!re are ?ree all-important features 9 ! fly+ ma*9e con/ruction1 viz41 lightness1 /r5g? & extreme rigidity4 ,spruce is ! wood g5]ally us$ = p>ts :5 lightness is desir$ m ?an /r5g?1 oak1 a%1 hickory & maple are all /rong]1 b !y are also consid]ably heavi]1 & :]e ! sav+ ( weight is ess5tial1 ! diff]5ce is l>gely 9 favor ( ! spruce4 ,?is w be se5 9 ! foll[+ cond5s$ table ( ,u4 ,s4 ,gov]nm5t ,specifications4 ---------------------------------------- ---------------------------------------- ------------------ ,weight p] ,modulus ( ,compression ,wood cubic foot1 rupture1 /r5g?1 p\nds 7#ae p\nds p] p\nds p] moi/ure7 squ>e in* squ>e in* ---------------------------------------- ---------------------------------------- ------------------ ,hickory #ej #af1cjj #g1cjj ,:ite ,oak #df #ab1jjj #e1ijj ,a% #dj #ab1gjj #f1jjj ,walnut #ch #aa1ijj #f1ajj ,spruce #bg #g1ijj #d1cjj ,:ite ,p9e #bi #g1fjj #d1hjj ---------------------------------------- ---------------------------------------- ------------------ ,a frequ5tly ask$ "q is3 8,:y is n alum9um or "s simil> metal1 sub/itut$ = wood80 ,wood1 p>ticul>ly spruce1 is pref]r$ because1 weight consid]$1 x is mu* /rong] ?an alum9um1 & ?is is ! lighte/ ( all metals4 ,9 ?is connection ! foll[+ table w be ( int]e/4 ---------------------------------------- ---------------------------------------- ---------------------------------------- ------ ,weight 9 ,t5sile ,compression ,mat]ial cubic feet1 /r5g? p] /r5g? p] sq4 9 p\nds sq4 9 p\nds p\nds ---------------------------------------- ---------------------------------------- ---------------------------------------- ------ ,spruce #bg #g1ijj #d1cjj ,alum9um #afb #ae1jjj #ab1jjj ,brass 7%eet7 #eaj #bj1jjj #ab1jjj ,/eel 7tool7 #dij #ajj1jjj #fj1jjj ,nickel /eel #dhj #ajj1jjja ,copp] 7%eet7 #edh #cj1jjj #dj1jjj ,tob9 bronze 7,turnbuckles7 444 #hj1jjj ,monel metal #edj #ij1jjj #cj1jjj ---------------------------------------- ---------------------------------------- ---------------------------------------- ------ ,wood4--,pres5t practice 9 airplane con/ruction is to use wood = practically all fram+1 9 o!r words1 = all p>ts :i* take pressure or compression4 ,al?\gh wood is n z /rong = its size z /eel & !re=e (f]s m air resi/ance = ! same /r5g? yet ! fact t frame p>ts mu/ n be too sp9dl+1 9 o!r words1 t !y mu/ h a c]ta9 ?ickness 9 proportion to _! unsupport$ l5g?1 has l$ to ! use ( wood 9 spite ( ! great] /r5g? ( /eel4 ,"s airplanes1 h[ev]1 z ! ,/urtevant1 are con/ruct$ ) practically a /eel fram+4 ,x %\ld be borne 9 m9d t any piece or k9d ( wood w n answ] = fram+1 & m especially = repair p>ts4 ,!re is a trem5d\s diff]5ce 9 ! /r5g? & suitability among diff]5t woods = ! "w4 ,= in/ance1 a piece ( wood ( cross or irregul> gra91 "o ) knots1 or ev5 "o :i* has be5 bor$ or cut or bruis$ on ! outside1 may h only half or less ! /r5g? ( ! orig9al piece4 ,air dry+ d\bles ! /r5g? ( gre5 wood1 prop] ov5 dry+ is bett] yet4 ,notice h[ ! ends ( ea* piece are f]rul$1 usually ) copp] or t94 ,?is is to prev5t ! bolt pull+ out ) ! gra9 ( ! wood1 & also prev5ts splitt+ & end *eck+ & gives a uni=m base on :i* ! pressure comes4 ,x is g5]ally advis$ n to pa9t wood z x t5ds to conceal defects f inspection4 ,s v>ni% only4 ,wrapp+ wood5 memb]s ) l95 or cord tightly & dop+ ?is1 bo? to make wat]pro( & to /ill fur!r tight51 increases ! resi/ance to splitt+4 ,! abs5ce ( w>p+ t5d5cies det]m9e (t5 :at wood to *oose4 ,! selection ( lumb] & detection ( flaws is a matt] ( exp]i5ce & %\ld be cultivat$4 ,x is1 h[ev]1 no?+ m ?an ! ext5sion ( ! k t leads a man to pick out a good baseball bat4 ,woods4--#a4 ,spruce4--,%\ld be cle>1 /raight-gra9$1 smoo? & free f knot holes & sap pockets1 & c>efully kiln-dri$ or season$4 ,x is ab\t ! lighte/ & = its weight ! /ronge/ wood us$4 ,x is ord9>ily us$ z a mat]ial = sp>s1 /ruts1 l&+ ge>1 etc41 z x has a prop] comb9ation ( flexibility1 lightness & /r5g?4 #b4 ,:ite ,p9e4--,a v light wood us$ = w+ ribs1 & small /ruts4 #c4 ,a%4--,spr+y1 /rong 9 t5sion1 h>d & t\gh1 b is consid]ably heavi] ?an spruce4 ,us$ = long]ons1 rudd] po/1 etc4 #d4 ,maple4--,us$ = small wood details1 z = blocks connect+ rib pieces across a sp> or = spac]s 9 a built-up rib4 #e4 ,h>d ,p9e4--,t\gh & uni=m & recomm5d$ = long pieces1 su* z ! wood5 braces 9 ! w+s4 #f4 ,walnut1 ,mahogany1 ,qu>t]-saw$ ,oak4--,! /r5g?1 uni=mity1 h>dness & f9i%+ qualities make ^! woods favorites = propell] con/ruction4 #g4 ,c$> ,wood4--,is us$ occasionally = fuselage cov]+s or = hull plank+ 9 hydroplanes z x is light1 uni=m & easily work$4 ,v5e]s1 or cross-glu$ ?9 lay]s ( wood1 are sometimes us$ = cov]+s4 ,lam9at$ or built-up wood5 memb]s h be5 mu* us$ = fram+ & = ribs & sp>s4 ,! eng9e be>]s are always ( wood on acc\nt ( vibration & are also lam9at$4 ,9 lam9ation ! wood5 /rut is built up ( sev]al pieces ( wood c>efully glu$ toge!r4 ,! gra9s ( ! diff]5t lay]s run 9 diff]5t directions1 consequ5tly a /rong] & m uni=m /ick (t5 is secur$4 ,! objection to lam9at$ pieces comes f ! wea!r caus+ unglu+4 ,lam9at$ pieces %\ld be wrapp$ 9 l95 or pap] & fre%5$ ) pa9t or v>ni% f "t to "t4 ,=ms4--,att5tion %\ld be call$ to ! holl[$ =m ( _m ( ! wood5 memb]s4 ,9 any beam or /rut1 mat]ial at ! c5t] ( ! cross-section is ( f> less value 9 tak+ ! load ?an ! mat]ial away f ! c5t]4 ,!re=e1 to secure greate/ /r5g? ) lea/ weight1 x is p]missible to light5 wood5 memb]s if done und]/&+ly4 ,/eel4--,!re is a trem5d\s diff]5ce 9 ! /r5g?1 we>+ & o!r desirable qualities among diff]5t /eels & irons4 ,= airplane "w none b ! be/ qualities are all[$4 ,= ?is reason ! use ( ord9>y iron bolts 7z /ove bolts7 or metal fa/5+s or wire n /&>diz$ & ( kn[n qualities %\ld n be p]mitt$4 ,! airplane is no /rong] ?an its weake/ fitt+4 ,?is does n mean t ! h>de/ & /ronge/ /eel mu/ necess>ily be us$1 z ease ( work+ & fre$om f brittl5ess may be j z important qualities1 b ! /eel on all metal fitt+s %\ld be ( high-grade uni=m /ock4 ,a ductile1 n too easily b5t1 mild c>bon /eel is usually recomm5d$ = all /eel plate1 clips1 sockets & o!r metal p>ts4 ,if any p>ts are requir$ to be temp]$ or h>d5$ x mu/ be rememb]$ t !y become brittle & c n aft]w>d be b5t )\t anneal+ or s(t5+4 ,tool or drill /eel is a "n giv5 to uni=m or r reliable grades ( /eel adapt$ to heat treatm5t z temp]+ or anneal+4 ,(t5 ! bolts1 clips1 nuts1 p9s1 devices & o!r fitt+s are ( special heat-treat$ nickel /eel :i* mu/ n be heat$ locally = b5d+ or = atta*m5t4 ,su* "w s]i\sly weak5s ! /eel4 ,! /eel is (t5 copp]-or nickel-plat$ & enamell$ to prev5t ru/+4 ,d n =get t ! prop] mat]ial may be twice z /rong z o!r mat]ial :i* looks ! same b :i* has n receiv$ special treatm5t4 ,wires4--,only ! highe/ grade ( /eel wire1 /r& & cord is all[able4 ,manufactur]s1 z ,roebl+ ( ,tr5ton1 ,n4 ,j41 manufacture special aviator wire & cord1 :i* is giv5 ! highe/ possible comb9ation ( /r5g? & t\ghness1 comb9$ ) ability to )/& b5d+1 etc4 ,/eel wire ropes = airplane "w are divid$ into ?ree classes z foll[s3 #a4 ,! solid wire #a wire 7z piano-wire grade7 & kn[n z aviation wire4 #b4 ,! /r& /ay1 consi/+ ei!r ( #g or #ai wires /r&$ toge!r & kn[n z 8aviator /r&40 ,fly+ & l&+ wires on ,curtiss4 #c4 ,cord or ,rope ,/ay4--,sev5 /r&s twi/$ toge!r =m+ a rope1 ea* /r& be+ ( #g or #ai wires & kn[n to trade z aviator cord4 ,! wires are ei!r t9n$ or galvaniz$ z protection aga9/ ru/1 etc4 ,ord9>ily galvaniz+ is us$1 b h>d wires & v small wires are injur$ by ! heat ( galvaniz+ & !y are !re=e t9n$4 ,no4 #a4 ,! s+le wire is ! /ronge/ = its weight4 ,s+le wires w n coil easily )\t k9k+ & are easily injur$ by a bl[1 !re=e _! use is conf9$ to ! protect$ p>ts ( ! ma*9e su* z brace wires 9 ! fuselage & 9 ! w+s4 ,! /r& /ay 7,no4 #b7 ( #g or #ai wires is g5]ally us$ = t5sion wires1 z x is m ela/ic 7c be b5t ar\nd small] curve7 )\t injury1 z ! fly+ & l&+ wires on ! ,curtiss4 ,! small] /r&s usually h #g wires1 ! l>g] ones #ai wires4 ,no4 #c4 ,! ,t9n$ ,aviator ,cord4--,! #g by #ai cord is us$ = /ays on =eign ma*9es4 ,x is #a times z ela/ic z a solid wire ( ! same mat]ial4 ,on ! ,curtiss x is us$ = control wires4 ,= /e]+ ge> & controls extra flexible aviator cord is also recomm5d$4 ,?is has a cotton c5t] :i* gives extra flexibility & is us$ = /e]+ ge> & controls4 ,x is #b times z ela/ic z a s+le wire4 ,al?\gh wire /r&s or cords are n q z /rong = ! same size z a s+le wire !y are pref]r$ = g5]al "w1 be+ easi] to h&le & because a s+le weak spot 9 "o wire does n s]i\sly injure ! :ole /r&4 ,especial c>e is necess>y to avoid us+ common /eel wires1 or /r&s :i* h a fray$ or brok5 wire1 or wire t has be5 k9k$ & !n /raight5$ or wire t has be5 locally heat$ or wire t has be5 bruis$4 ,all ^! factors weak5 /eel rope mu* m ?an is suppos$ ord9>ily4 ,wire ,fa/5+ or ,t]m9al ,connections4--,wire t]m9als are ( f\r classes3 #a4 ,f]rule & dip 9 sold]1 !n b5d back ! end4 ,) or )\t ?imble2 us$ on s+le wires or on /r&2 #ej to #id p] c5t4 z /rong z ! wire4 #b4 ,?imble & ,end ,splic+4--,! splice mu/ be long & complete4 ,us$ on cable2 #hj to #he p] c5t4 z /rong z ! /r&2 breaks at la/ tuck 9 ! splice4 #c4 ,socket4--,ne>ly #ajj p] c5t4 /rong4 #d4 ,end ,wrap & ,sold]4--,simple & s]viceable2 n us$ = h>d wire4 ,pres5t practice is r t[>d elim9ation ( acid & sold]1 imp]fect b5ds1 flatt5+ ( cable on b5ds1 & t[>d c>e 9 avoid+ all injury z k9k+ to wire1 /r& & cord due to unskillful h&l+ ( mat]ial 9 ! field4 ,o!r ,metals4--,o!r metals z alum9um1 brass1 bronze1 copp]1 monel metal 7copp] & nickel7 are us$ = c]ta9 airplane fitt+s = ! reasons ( lightness1 non-corrosive qualities1 or ease ( b5d+1 etc4 ,! tr\ble ) ^! metals is t !y are n uni=m & reliable 9 /r5g? & 9 an important "p ! great /r5g? comb9$ ) m9imum weight giv5 by /eel is n equall$ by any ( ^! metals4 ,alum9um is us$ on ! eng9e hood & also = control lev]s & = ! backs ( ! seats4 ,9 o!r words1 = p>ts & ca/+s :i* require light metal con/ruction1 b :i* are "u no p>ticul> /ress4 ,t9 & copp] are us$ = f]rules ( wire jo9ts & = tankage4 ,copp] or brass wire are us$ = safety wires4 ,special ,tob9 bronze is us$ = turnbuckles z ! "p mu/ n only be /rong b free f any t5d5cy to ru/4 ,monel metal 7nickel #fj p] c5t41 copp] #ce p] c5t41 iron #e p] c5t47 is /rong & has ! special prop]ty ( be+ acid- & ru/-resi/+4 ,x has be5 us$ = metal fitt+s & ev5 = wires & = ! wat] jacket ( ! motor4 ,until m /r5g? te/s %[ great] uni=mity ( /r5g?1 x is to be recomm5d$ ) caution4 ,9 deal+ ) metals l /eel1 x %\ld be rememb]$ t !y are subject to cry/allization & fatigue4 ,repeat$ j>r+ may cause a b> ( /eel to break easily at a p>ticul> po9t1 :5 ! metal is said to h cry/alliz$ !re4 ,fatigue ( a metal may be def9$ z loss ( spr+9ess :i* may come f repeat$ b5d+ & :i* less5s ! /r5g? ( metal4 ,above all1 h[ev]1 corrosion ( /eel mu/ be gu>d$ aga9/4 ,! above po9ts %\ld be cle>1 z 9 airplane "w y are deal+ ) a /ructure :i* is safe ) p]fect mat]ials & workman%ip4 ,! factor ( safety1 h[ev]1 is n great en\gh to p]mit c>elessness1 or defective mat]ial4 ,l954--,! almo/ univ]sal w+ cov]+ is f9e1 unblea*$ ,iri% l951 /ret*$ r loosely on ! w+ frames & !n treat$ ) dope4 ,! l95 us$ weighs #c to #d oz4 p] squ>e y>d1 & %\ld h a /r5g? ) ! l5g? ( ! clo? or 8w>p0 ( at lea/ #fj lb4 p] in* ( wid?4 ,! /r5g? 9 ?is direction is slightly great] ?an t tak5 crosswise ( ! clo? or on ! fill] or weft4 ,!re is a ga9 ( /r5g? & tautness by v>ni%+ or 8dop+40 ,9 g5]al1 x is desirable to h w+ mat]ial :i* w n sag easily & h ! fabric yield r ?an break4 ,?is (t5 r$uces /ress & saves complete failure4 ,dope4--,! l95 mu/ be coat$ ) a m or less wat]pro( dope4 ,"s =m ( cellulose acetate or nitrate ) m or less s(t5+ mat]ial is us$ & to ^! "s suitable solv5t z acetone is add$4 ,! cellulose acetate or nitrate 9 ! dope acts z a wat]pro( siz+1 %r9ks ! clo? tight1 & prev5ts x f *ang+ 9 tightness due to moi/ure4 ,sp> v>ni% protects ?is lay] f peel+ & makes ! w+ m wat]pro(4 ,9 s]vice1 v>ni% or dope mu/ be appli$ e few weeks4 ,! ,u4 ,s4 ,army practice calls = f\r coats ( cellulose nitrate dope foll[$ by two coats ( sp> v>ni% to prev5t inflammability4 ,cellulose nitrate is m ela/ic & durable ?an ! acetate b is also m inflammable4 ,comm]cial dopes ) v>i\s desirable prop]ties are3 ,cellon1 ,novavia1 ,emaillite1 ,cav>o1 ,titan9e1 etc4 ,,footnotes3 #a ,b has v high ela/ic limit4 ,,*apt] ,,viii ,,erect+ ,,airplanes ,airplanes %ipp$ f ! manufactur] or f ano!r field almo/ always suff] m or less f %ipm5t or pack+4 ,c>e mu/ be ex]cis$ 9 unpack+ 9 ord] n to d any m damage4 ,boxes %\ld be plac$ ) ! "p m>k$ 8,top0 upp]mo/4 ,cables & wires mu/ be h&l$ c>efully 9 ord] n to b5d or twi/ !m4 ,e b5t or k9k$ wire or damag$ turnbuckle mu/ be replac$1 or at lea/ br\ght to ! att5tion ( an inspector4 ,! ord] ( erection is z foll[s3 #a4 ,assemble l&+ ge> to fuselage & align l&+ ge> be=e putt+ on ma9 panels4 #b4 ,assemble tail4 #c4 ,assemble eng9e section & align be=e atta*+ ma9 panels4 #d4 ,assemble ma9 panels4 #a4 ,l&+ ,ge> ,assembly to ,fuselage4--,! l&+ ge> is assembl$ by m\nt+ ! :eels on ! axle1 & bolt+ :eels 9 place4 ,! fuselage %\ld n[ be elevat$ to receive ! l&+ ge>4 ,?is may be accompli%$ 9 "o ( two ways--ei!r by tackle or by %ims & block+4 ,= ei!r me?od1 fir/ connect up ! tail skid4 ,?is is accompli%$ by p9n+ up ! front end ( ! skid to ! spr+-fitt+1 & !n p9n+ 9 ! o!r end to ! tail-po/ socket4 ,if block & tackle are us$ to raise ! fuselage1 pass a l9e "u ! eng9e-b$ supports or sills j to ! re> ( ! radiator4 ,to ?is l9e atta* hook ( block4 ,to avoid damag+ or cru%+ "s "p d n atta* lift+ device to any o!r po9t4 ,) ! fuselage n[ re/+ on its atta*$ tail skid1 lift ! front end until ! l[] long]on clips cle> ! l&+ ge>4 ,:5 ! clips on ! long]ons l9e up ) ! clips on ! ends ( ! /ruts ( ! l&+ ge> ! bolts are pass$ d[n ?r\gh ! holes ?us align$4 ,?is places ! nuts on ! d[n side ( ! connection ?us facilitat+ assemblies & inspection ( connections4 ,! ca/ellat$ nuts are !n put on ! bolts & drawn up tight1 until ! drill$ hole 9 ! bolt is visible ?r\gh ! ca/le ( ! nut4 ,!n ins]t cott]-p9 & spread ! two leaves backw>d ov] ! nut4 ,?is locks ! nut 9 place4 ,:5 ! l&+ ge> has be5 completely assembl$ to ! fuselage1 ! tail ( ! ma*9e %\ld be elevat$ & support$ by a horse & block+ until ! upp] long]on is level4 ,?is c be det]m9$ by plac+ a _s level on ! upp] long]on at ! tail or on ! two eng9e-b$ sills 9 ma*9es :]e ^! sills are p>allel to ! top long]on1 z 9 ,curtiss ,,jn-#d;,b4 #b4 ,horizontal ,/abiliz]4--,aft] ! upp] long]on is levell$ up1 ! horizontal /abiliz] is assembl$ to ! tail ( ! fuselage4 ,! horizontal /abiliz] is fa/5$ by means ( bolts 9 ! top long]on & ! tail po/4 ,! nuts are all drawn up tight & cott]-p9n$4 ,! v]tical /abiliz] is next erect$ 9 place4 #c4 ,v]tical ,/abiliz]4--,! v]tical /abiliz] is n[ fa/5$ to ! horizontal /abiliz]1 fir/ by means ( ! bolt :i* passes up ?r\gh ! =w>d "p ( ! horizontal /abiliz] & !n by means ( ! flexible /ay l9es runn+ f ! top ( ! v]tical /abiliz]4 ,! =w>d bolt passes ?r\gh ! clip at ! l[] front po9t ( ! v]tical /abiliz]4 ,draw ! nuts up tight & lock ) cott]-p9s4 ,flexible wire cables are atta*$ to v]tical /abiliz]1 & turnbuckles are us$ to align & tight5 cables4 ,! v]tical /abiliz] is fur!r aid$ 9 its alignm5t by ! bolt clip at its toe & by ! d\ble clip at its heel4 ,?is re> d\ble clip passes ov] ! two bolts :i* are atta*$ to ! tail po/ & :i* hold d[n ! horizontal /abiliz]4 #d4 ,rudd]4--,! control braces are fir/ atta*$ to ! rudd]4 ,^! braces are s plac$ t ! upp] tips po9t t[>d ! h+e l9e4 ,9 ?is fa%ion ! holes w mat* up4 ,! rudd] is m\nt$ on ! tail po/ & v]tical /abiliz] by means ( ! h+es4 ,! h+e p9s are ins]t$ 9 ! h+es1 & cott]-p9s pass$ ?r\gh ! drill$ holes 9 ! bottom ( ! p9s4 ,! cott]-p9s %\ld be spread backw>d z usual4 #e4 ,elevators or ,flaps4--,^! are fir/ equipp$ ) ! control braces :i* are also arrang$ s t ! upp] tips po9t t[>d ! h+e l9e4 ,! elevators are m\nt$ to ! horizontal /abiliz] by means ( ! h+es & h+e p9s4 ,! h+e p9s are kept 9 _! be>+s by ! cott]-p9s1 ins]t$ ?r\gh ! drill$ holes 9 ! bottom ( ! h+e p9s4 #f4 ,panel ,assembly4--,! panels are n[ to be assembl$4 ,be=e ! ma9 panels c be connect$ to ! fuselage1 ! eng9e section panel mu/ be erect$4 ,eng9e ,section ,panel4--,! eng9e section /ruts are fir/ set into place 9 _! sockets on ! eng9e section4 ,!n ! :ole ?+ is lift$ up to place & ! f\r /ruts are set into _! sockets on ! upp] long]on4 ,! brac+ wires are atta*$ & ! eng9e section align$ by means ( !m 7see alignm5t74 #g4 ,ma9 ,panels4--,! ma9 panels are n[ to be assembl$ to ! ma*9e4 ,!re are two me?ods = accompli%+ ?is3 fir/1 assemble panels1 /ruts & wires1 be=e atta*+ to fuselage2 second1 assemble ! upp] plane to ! eng9e section1 & complete assembly4 ,! fir/ me?od is ! mo/ advantage\s1 s9ce x p]mits ! sett+ ( ! ma9 panels at ! correct /agg] & dih$ral1 & does n require z mu* adju/m5t z ! second me?od1 :i* w be omitt$4 ,assembl+ ,panels ,toge!r ,be=e ,fa/5+ ,!m to ,fuselage4--,all ! ma9 /ruts w be f\nd to be> a numb]4 ,^! numb]s run f #a to #h1 on ,curtiss ,,jn-#d4 ,! numb]s on ! ,/&>d run f #a to #ab includ+ ! c5t] section /ruts4 ,! me?od us$ 9 numb]+ ! po/s is z foll[s3 ,/>t+ at po/ ,no4 #a1 ) ! out] po/1 on ! left-h& side ( ! pilot1 z he faces 8 direction ( travel1 ! po/s are numb]$ successively f ,no4 #a to ,no4 #d2 ,nos4 #a & #b be+ on ! left side & ,nos4 #c & #d be+ on ! "r side4 ,! re> po/s are simil>ly numb]$ f ,no4 #e to ,no4 #h1 ,nos4 #e & #f be+ on ! left & ,nos4 #g & #h be+ on ! "r4 ,?is sy/em ( numb]+ does n include ! eng9e section /ruts4 ,! plan %[s ! sy/em graphically 7see ,fig4 #ci74 ,! sy/em ( m>k+ also insures t ! /ruts are n inv]t$ 9 _! sockets4 ,?is is accompli%$ by pa9t+ ! numb] on ! /rut1 s t :5 view$ f ! pilot's seat1 all numb]s c be read1 i4e41 ! numb]s are pa9t$ on t side ( ! /rut int5d$ to face ! fuselage4 ,if a /rut is inv]t$ by mi/ake1 x c ?us be quickly detect$4 ,! proc$ure ( assembl+ panels is z foll[s3 #a4 ,! upp] left-w+ panel is fir/ equipp$ ) ma/1 by ins]t+ ! ma/ into its socket on ! upp] surface ( ! w+4 ,! ma/ wire is !n connect$ up to ! clips to ! "r & left ( ! ma/4 ,adju/ ! t5sion 9 ?is wire1 by means ( turnbuckles1 until ! sp> becomes /raight4 #b4 ,/& ! upp] left-w+ panel & l[] left-w+ panel on _! 8lead+0 or 8ent]+0 edges1 prop]ly support+ ! panels 9 cu%ion$ blocks to prev5t damage to ! nose4 ,space ! panels ap>t1 at a di/ance approximately equal to ! l5g? ( ! /ruts4 #c4 ,next connect up ! diagonal cross wires4 ,^! mu/ be loosely connect$ up1 to p]mit ! easy ent]+ ( ! po/s into ! sockets4 ,! wires are connect$ be=e ! po/s or /ruts are set 9 place1 s9ce ) ! latt] 9 place1 ! connect+ ( ! wires to ! lugs ( ! sockets is accompli%$ only ) difficulty4 ,aft] ^! wires are ?us connect$1 ins]t ! po/s & bolts into place4 #d4 ,connect up closely ! 8l&+0 7s+le7 wires1 & 8fly+0 7d\ble7 wires ( ! out] bay to hold ! w+s toge!r z a unit4 ,! out] bay is ?us completely wir$1 ?\gh b loosely4 #e4 ,! po/s t are us$ = ?is left side are1 accord+ to ! diagram1 ,no4 #a1 ,no4 #b1 ,no4 #e1 ,no4 #f4 ,no4 #a is ! out] front2 ,no4 #b is ! inn] front2 ,no4 #e is ! out] re>2 ,no4 #f ! inn] re>4 #f4 ,! w+s1 z above assembl$1 are n[ erect$ to ! fuselage4 ,extreme c>e %\ld be ex]cis$ 9 transf]r+ ! w+s to ! fuselage1 n to /ra9 or break !m4 ,9 c>ry+ ! w+s1 use wood5 bo>ds plac$ "u ! w+s1 & block up "u ! w+ beams 7:i* c be easily locat$71 s t ^! take ! /ra9 ( ! load4 ,d n attempt h&l+ assembl$ w+s1 us+ ! po/s z c>ri]s2 or by atta*m5ts to ! trail+ or lead+ edges4 ,! w+s %\ld be suitably support$ tempor>ily by suitable sl+ at ! out] upp] po/ po9t 7n beyond ?is po9t7 or by a horse1 prop]ly block$ "u l[] w+ at out] l[] po/ po9t 7n beyond ?is po9t7 dur+ fitt+ ( w+ to ma*9e4 ,! w+s w h ! approximate /agg] if assembl$ z above1 s9ce ! po/s are 9 place1 & ! t5sion cross wires are adju/$ to almo/ correct l5g? :5 %ipp$4 ,ins]t ! h+e p9s ?r\gh ! h+es z n[ c\pl$ up1 l[] h+es fir/4 ,! ma*9e is n[ ready = alignm5t1 p]haps ! mo/ important ( ! rigg]'s duties4 ,alignm5t ( ,airplanes4--,! prop] alignm5t ( a ma*9e l>gely det]m9es ! fly+ qualities ( t ma*9e4 ,! alignm5t ( ! fuselage %\ld be done at ! factory or 9 ! repair %op4 ,h[ev]1 ! alignm5t ( ! :ole ma*9e dep5ds ^u ! correctness ( ! fuselage4 ,directions = align+ & *eck+ fuselage are1 !re=e1 giv54 ,! ord] 9 :i* ! diff]5t p>ts ( a ma*9e %\ld be align$ is z foll[s3 #a4 ,alignm5t ( l&+ ge>4 #b4 ,alignm5t ( c5t] section4 #c4 ,alignm5t ( lead+ edge4 #d4 ,gett+ bo? w+s ! same height4 #e4 ,dih$ral angle1 if any4 #f4 ,alignm5t ( trail+ edge 7angle ( incid5ce74 #g4 ,/agg]4 #h4 ,droop4 #i4 ,tight5+ & safety+ all wires4 #aj4 ,l5g? ( /ruts1 positions & fitt+s1 w>p 9 planes4 #aa4 ,alignm5t ( ail]ons4 #ab4 ,alignm5t ( /abiliz]4 #ac4 ,alignm5t ( elevator flaps4 #ad4 ,alignm5t ( rudd]4 ,! tail ( ! ma*9e %\ld be rais$ until ! fuselage is ne>ly horizontal be=e />t+ ! alignm5t4 #a4 ,alignm5t ( ,l&+ ,ge>4--,:5 a ma*9e is be+ assembl$1 x is easi] to align ! l&+ ge> be=e ! w+s are put on4 ,take ! weight (f ! l&+ ge> by support+ ! fuselage on sa:orses4 ,! axle %\ld be p>allel ) ! lat]al axis ( ! ma*9e4 ,! c5t] ( ! axle %\ld be directly "u ! c5t] ( ! fuselage4 ,?is c be secur$ by ei!r ( two me?ods3 7a7 ,by ,measur+ ,cross ,di/ances4--,loos5 & tight5 ! cross wires until ! cross di/ances are exactly ! same4 ,take all measurem5ts f simil> po9ts on ! fitt+s to :i* ! wires are atta*$4 7b7 ,) ,level & ,plumb ,bob4--,level ! fuselage crosswise4 ,m>k ! exact c5t] ( ! fuselage & drop a plumb bob4 ,m>k ! exact c5t] ( ! axle4 ,adju/ ! cross wires until ! plumb bob is ov] ! c5t] ( ! axle4 ,tight5 ! wires until fairly tight1 & safety !m4 #b4 ,alignm5t ( ! ,c5t] ,section4--,:5 assembl+ a ma*9e1 ! c5t] section %\ld be align$ be=e ! w+s are put on4 ,:5 a ma*9e is already assembl$1 ! fir/ ?+ to d is to loos5 all wires except ! l&+ wires4 ,?is is v important1 = if "o wire is tight5$ aga9/ ano!r wire1 an unnecess>y & possibly a dang]\s /ra9 may be put ^u "s memb]4 ,! brac+ wires connect+ tops ( c5t] section /ruts %\ld be tight en\gh to hold ! %ape ( ! c5t] section :5 brac+ wires are tight5$ up4 ,illu/ration3 ,,fig4 #ch4--;,c5t] section & und]c>riage alignm5t4 7a7 ,ma*9es ,hav+ ,no ,/agg]4--,9 ma*9es hav+ no /agg]1 ! /ruts ( ! c5t] section %\ld be p]p5dicul> to ! propell] axis4 ,z ! upp] long]ons are usually p>allel to ! propell] axis1 !y may be us$ z a base l9e4 ,align "o side ( ! c5t] section fir/1 !n ! o!r side1 & la/ly ! front4 ,f a po9t at ! l[] end ( "o ( ! front c5t] section /ruts 7! c5t] ( a bolt head = example71 measure =w>d on ! long]on a c]ta9 di/ance4 ,f ! same po9t 7c5t] ( bolt head7 measure back on ! long]on exactly ! same di/ance4 ,move ! upp] end ( ! /rut =w>d or backw>d by loos5+ "o ( ! brac+ wires & tight5+ ! o!r1 until ! di/ance f ! two po9ts on ! long]ons to "s po9t on ! c5t] l9e at ! top ( ! /rut 7c5t] ( bolt head7 are exactly ! same4 ,! /rut w !n be p]p5dicul> to ! propell] axis4 ,tight5 bo? wires ev5ly until fairly tight4 ,measure ! cross di/ances 7! diagonal di/ances betwe5 simil> po9ts at ! upp] & l[] ends ( ! front & re> /ruts71 & align ! o!r side ( ! c5t] section until its cross di/ances are ! same z ^? on ! opposite side4 ,align ! front ( ! c5t] section by loos5+ "o cross wire & tight5+ ! o!r1 until "o cross di/ance is exactly ! same z ! o!r cross di/ance4 7b7 ,ma*9es ,hav+ ,/agg]4--,9 ma*9es hav+ /agg]1 ! %ape & position ( ! c5t] section /rut fitt+s usually det]m9es ! am\nt ( /agg] ! ma*9e 0 design$ to h 7,fig4 #ch-;a74 ,! ,,jn-#d has #aj-;94 /agg]1 i4e41 a plumb l9e dropp$ f ! lead+ edge ( upp] panel %\ld be #aj-;94 f lead+ edge ( l[] panel4 ,adju/ ! wires on "o side ( ! c5t] section until ! /ruts & t side are 9 _! correct positions z %[n by ! %ape ( ! fitt+s4 ,tight5 ! wires1 measure ! cross di/ances1 & adju/ ! wires on ! o!r side ( ! c5t] section until ! cross di/ances are exactly simil> to ! fir/ set4 ,a m accurate me?od is to drop a plumb l9e f ! lead+ edge ( ! c5t] section & adju/ until ! l9e is at ! correct di/ance ahead ( ! po9t on ! fuselage :]e ! lead+ edge ( ! l[] w+ meets x4 ,?is po9t may be det]m9$ by measur+ ! di/ance f ! inside ( ! front h+e to ! lead+ edge ( ! l[] w+ & !n lay+ (f ?is di/ance on ! body f ! front ( ! h+e on ! l[] long]on4 ,bett] /ill1 if ! h+es are at ! same di/ance f ! lead+ edge on bo? top & bottom w+s1 ! plumb l9e may be dropp$ f ! front side ( ! h+e on ! c5t] section & ! /agg] measur$ back to ! h+e on ! l[] long]on 7,fig4 #ch-;b74 ,?is has ! advantage ( sett+ ! plumb l9e out f> en\gh to cle> ! fuselage4 ,also ! measurem5ts are easily made4 ,next1 adju/ ! two front wires until "o cross di/ance is exactly ! same z ! o!r cross di/ance 7,fig4 #ch-;c74 #c4 ,alignm5t ( ,lead+ ,edge4--7a7 ,upp] ,plane4--,! lead+ edges ( ! upp] & l[] planes ( "o w+ %\ld next be made p]fectly /raight4 ,by /&+ on a /ep ladd]1 plac$ #ae to #bj ft4 to "o side1 & sight+ along ! lead+ edge ( ! upp] plane1 any b[ or w>p c be easily se54 ,?is %\ld be /raight5$ out by loos5+ or tight5+ ! front l&+ wires4 ,! edge %\ld be br\ght 9 exact l9e ) ! lead+ edge ( ! c5t] section4 7b7 ,l[] ,plane4--,aft] ! lead+ edge ( ! upp] plane has be5 made /raight1 sight along ! lead+ edge ( ! l[] plane4 ,if !re is no w>p 9 ! plane1 ?is edge %\ld also be /raight4 7c7 ,align ! opposite w+ 9 ! same mann]4 #d4 ,gett+ ,bo? ,w+s ! ,same ,height4--,place a small tack exactly 9 ! middle ( ! lead+ edge ( ! c5t] panel4 ,measure f ?is tack to simil> po9ts at ! l[] ends ( ! int]m$iate & out] /ruts 7,fig4 #ci74 ,make ^! di/ances ! same on ea* side by rais+ or l[]+ "o w+ or ! o!r1 or by rais+ "o w+ & l[]+ ! o!r w+1 all ! :ile keep+ ! lead+ edges ( bo? w+s p]fectly /raight4 #e4 ,dih$ral4--,! me?od ( sett+ ! w+s ( a ma*9e at a dih$ral angle is z foll[s3 ,place two tacks 9 ! lead+ edge ( ! upp] plane1 "o tack ne> ! tip ( ea* w+ & exactly ! same di/ance out f ! tack 9 ! c5t] section4 ,/ret* a /r+ tightly betwe5 ! two out] tacks1 until !re is no sag 9 ! /r+4 ,a dih$ral angle ( #agh means t ea* w+ has be5 rais$ #a4 ,to set ! w+s ( a ma*9e at a dih$ral angle ( #agh = example3 7a7 ,f9d ! natural s9e ( #a 7#j4jage74 7b7 ,multiply ?is by ! di/ance 9 in*es betwe5 ! c5t] tack & "o ( ! out] tacks4 ,! result w give ! rise1 9 in*es1 ( ! /r+ ov] ! tack 9 ! c5t] section4 ,raise ! w+s equally1 keep+ ! lead+ edges p]fectly /raight1 until ! prop] rise %[s ov] ! c5t] section4 ,illu/ration3 ,,fig4 #ci4--;,alignm5t diagrams4 #f4 ,alignm5t ( ,trail+ ,edge 7,angle ( ,incid5ce74--7a7 ,l[] ,plane4--,! trail+ edge %\ld be br\ght p>allel to ! lead+ edge4 ,?is c be done by br++ ! re> sp> 9 l9e ) ! lead+ edge4 ,/& squ>ely 9 front ( ! c5t] ( ! ma*9e #ae to #bj ft4 away4 ,sight "u ! lead+ edge ( ! l[] plane2 move =w>d or backw>d until ! fitt+s "u ! re> sp> are j visible4 ,raise or l[] ! trail+ edge by loos5+ or tight5+ ! re> l&+ wires1 until all ( ! fitt+s on ! re> sp> appe> equally "u ! lead+ edge4 7b7 ,upp] ,plane4--,aft] align+ ! trail+ edge ( ! l[] plane1 place a ladd] 9 front ( ! c5t] ( ! ma*9e1 & sight "u ! lead+ edge ( ! upp] plane4 ,if !re is no w>p 9 ?is plane1 ! trail+ edge %\ld align ) ! lead+ edge4 ,! objection to ?is me?od is t s9ce !re are no fitt+s next ! body on ! re> sp>1 !re is room = consid]able error 9 ! angle ( incid5ce4 ,rev]s+ ! process & f9d+ ! angle ( incid5ce at ea* set ( /ruts secures ! alignm5t ( ! trail+ edge & removes ! liability to error4 ,to set w+s at correct angle ( incid5ce proce$ z foll[s 7,fig4 #ci73 ,place ! airplane 9 rigg+ position1 i4e41 level up ! top long]on or eng9e be>]s4 ,set ! corn] ( ! /raight-edge aga9/ ! c5t] ( ! re> sp>1 level up ! /raight-edge1 & measure f ! top ( ! /raight-edge to ! c5t] ( ! front sp> or to ! l[e/ po9t ( ! lead+ edge4 ,?is mu/ be done next ! body & "u ea* set ( /ruts4 7,x is useless to make su* a measurem5t betwe5 ! /ruts because ( possible w>p+ ( ! w+s47 ,unless ! w+s h a wa%\t or wa%9 ! measurem5ts mu/ agree1 ?us mak+ ! angle ( incid5ce ! same all along ! w+4 ,!n ! trail+ edge mu/ necess>ily be p>allel to ! lead+ edge4 #g4 ,/agg]4--,! /agg] %\ld be ! same all along ! w+ z x is = ! c5t] section4 ,) ! ma*9e 9 rigg+ position drop a plumb l9e f ! lead+ edge ( ! upp] w+ 9 front ( ea* set ( /ruts4 ,! di/ance f ! plumb l9e to ! l[] edge %\ld equal ! /agg]4 ,if !re is too mu*1 tight5 ! diagonal wire runn+ f ! l[] re> socket to ! upp] front socket1 be+ sure t ! o!r diagonal wire is loos5$ some:at4 ,= too little /agg] tight5 ! latt] & loos5 ! =m] wire4 ,*eck up ! dih$ral & alignm5t ( ! trail+ edges to see if ^! h be5 di/urb$ :ile sett+ ! /agg]4 ,if n1 ! droop may be put 94 #h4 ,droop4--,to correct = ! torque ( ! propell]1 "o w+ ( a ma*9e is slightly droop$4 ,9 s+le-motor$ tractor types1 if ! propell] turns to ! "r1 :5 look+ f ! re>1 ! left w+ is droop$1 & vice v]sa4 ,! out] re> l&+ wire ( ! w+ to be droop$ %\ld be loos5$ until ! trail+ edge1 betwe5 ! out] & int]m$iate /ruts1 appe>s to be ab\t an in* 7= ma*9es ( n m ?an #ajj hp47 l[] ?an ! re/ ( ! trail+ edge4 ,! practice ) ! ,curtiss ,,jn-#d;,b is to loos5 ! inn] re> l&+ wire on ! left w+ 94 & loos5 ! out] re> l&+ wire 94 aft] ! angle ( incid5ce & /agg] h be5 adju/$ s t correspond+ wires on ! "r & left w+s are ! same l5g?4 #i4 ,tight5+ & ,safety+ ,all ,wires4--7a7 ,aft] ! w+ is droop$1 all fly+ wires %\ld be tight5$ to ! same t5sion1 & j taut en\gh to take out all sag4 7b7 ,next tight5 all drift or cross wires betwe5 ! front & re> /ruts to ! same t5sion4 7c7 ,drift wires f ! w+s to ! fuselage1 & f ! w+s to ! l&+ ge>1 if any1 %\ld be tight5$ la/4 7d7 ,safety all turnbuckles4 ,a wire too loose w vibrate :5 ! ma*9e is 9 ! air4 ,! fly+ & drift wires %\ld be s tight5$ t :5 !y take ! weight ( ! ma*9e 9 ! air1 !re w be no sag 9 ! l&+ wires4 #aj4 ,l5g? ( ,/ruts1 ,positions ( ,fitt+s1 ,w>p 9 ,planes4--,! above in/ructions are giv5 = ma*9es t are true1 t is1 ma*9es hav+ no b5ds1 w>ps1 or b[s 9 ! sp>s & lead+ or trail+ edges4 7a7 ,simil> /ruts %\ld be ( ! same l5g?4 7b7 ,simil> fitt+s occupy+ simil> positions %\ld be spac$ ! same4 ,if difficulties are enc\nt]$ 9 gett+ ! measurem5ts to tally1 *eck up ! l5g?s ( ! /ruts & ! positions ( ! fitt+s4 7c7 ,if ! planes ( a ma*9e are w>p$1 ! ma*9e %\ld be s align$ t ! w>p is equally divid$ betwe5 bo? planes4 #aa4 ,alignm5t ( ,ail]ons4--,be=e align+ ail]ons1 place ! %\ld] yoke or :eel controll+ ! ail]ons 9 ! c5t] ( its pa? ( movem5t4 7a7 ,trail+-edge ,ail]ons4--,trail+-edge ail]ons %\ld be set in* l[] ?an ! trail+ edge ( ! plane to :i* !y are atta*$4 7b7 ,int]plane ,ail]ons4--,int]plane ail]ons %\ld be set s t !y are bo? 9 ! same plane1 :5 9 neutral position4 ,9 ma*9es hav+ int]plane ail]ons1 nose heav9ess & tail heav9ess may be correct$ by sett+ ! trail+ edges ( ! ail]ons up or d[n4 ,! prop] am\nt to raise or l[] ! trail+ edges c be det]m9$ only by exp]im5t+ ) ea* p>ticul> type ( ma*9e4 7c7 ,! control wires %\ld be j tight en\gh to elim9ate any lo/ motion4 #ab4 ,alignm5t ( ,/abiliz]4--,support ! weight ( ! tail on ! tail skid4 ,! re> edge ( ! /abiliz] %\ld be p]fectly /raight1 & %\ld be p>allel ) lat]al axis ( ! ma*9e4 ,/& beh9d ! c5t] ( ! /abiliz]1 & align its re> edge on ! lead+ edge ( ! upp] plane by sight+4 ,tight5 wires & safety turnbuckles4 #ac4 ,alignm5t ( ,elevator ,flaps4--,set ! elevator control 9 its mid-position4 ,adju/ ! elevator control wires until ! flaps are 9 _! neutral position & bo? are 9 ! same plane4 ,! wires %\ld be j tight en\gh to elim9ate any lo/ motion4 ,safety turnbuckles4 #ad4 ,alignm5t ( ,rudd]4--,set ! rudd] control 7:eel1 foot p$als1 or foot b>7 9 its mid-position4 ,adju/ ! rudd] control wires until ! rudd] is 9 its neutral position4 ,! control wires %\ld be j tight en\gh to elim9ate any lo/ motion4 ,safety ! turnbuckles4 #ae4 ,g5]al4--,all connections hav+ be5 made1 c>efully g ov] ea* %ackle1 p91 & turnbuckle1 & see t all p9s are prop]ly 9 place1 all nuts on bolts tight & all cott]-p9n$4 ,try out all controls = action & fre$om ( movem5t4 ,see t no brace wires are slack1 yet n s taut t :5 pluck$ !y 8s+40 #af4 ,ov]all ,adju/m5ts4--,z a f9al *eck1 ! foll[+ ov]all measurem5ts %\ld be tak5 7see ,fig4 #ci74 ,! /raight l9es ,,ac & ,,bc %\ld be equal to )9 94 ,! po9t ,c is ! c5t] ( ! propell]1 or 9 ! case ( ! pu%] ! c5t] ( ! nacelle4 ,a & ,b are po9ts on ! ma9 sp> & mu/ be at ! same di/ance f ! butt ( ! sp>4 ,!y mu/ n be m]ely ! sockets ( ! out] /ruts z ^! may n be accurately plac$4 ,,ac & ,,bc mu/ be tak5 f bo? top & bottom sp>s2 two measurem5ts on ea* side ( ! airplane4 ,simil>ly ,,fd & ,,fe %\ld be equal to )9 94 ,f is ! c5t] ( ! fuselage or rudd] po/4 ,d & ,e are po9ts m>k$ on bo? top & bottom re> sp>s j z ,a & ,b 7 m>k$ on front sp>s4 ,if ^! measurem5ts are n correct1 x is probably due to "s ( ! drift or antidrift wires be+ too tight or too slack4 ,^! mu/ !n be locat$ & correct$4 ,,w+ ,,cov]+ ,,& ,,pat*+ ,! w+s are cov]$ ) be/ quality ,iri% l95 :i* mu/ h a t5sile /r5g? ( at lea/ #ej lb4 p] in* wid?1 undop$1 & #gj lb4 :5 dop$4 ,! l95 /rips are sew$ toge!r on a sew+ ma*9e 9 su* a way t :5 fold$ toge!r !y =m a sort ( bag :i* j slips ov] ! w+ frame4 ,! seams !n run diagonally across ! w+4 ,! bag is /ret*$ up loosely & tack$ tempor>ily along ! lead+ edge4 ,! edges are fold$ "u a little & sew$ toge!r along ! lead+ edge ( ! w+ & ! tempor>y tacks are remov$4 ,to hold ! cov]+ up to ! ribs1 ?read is loop$ ?r\gh f "o side ( ! panel to ! o!r ar\nd ! ribs4 ,! r\gh surfaces made by ! ?read along ! ribs & ! edges are cov]$ ov] ) /rips ( l95 pa/$ on ) dope4 ,to make a smoo? job1 ! edges ( ^! /rips are fray$ out 94 ,?ree or m coats ( dope are appli$ & rubb$ d[n aft] ea* coat+ is dry4 ,?is is !n cov]$ ov] ) "o or two coats ( v>ni% to make x m wea!rpro( & smoo?4 ,v>ni% also prev5ts ! dope f peel+ (f4 ,dope %r9ks ! l95 & makes x fit up tight to ! framework4 ,breaks 9 ! fabric are pat*$ by fir/ remov+ ! dope ar\nd ! break ) dope remov] & !n /ick+ on a pat* ) dope4 ,?is is appli$ ) a rag in/ead ( a bru% 9 ord] to prev5t ! pat* f becom+ :ite4 ,t5 to sixte5 coats ( dope are !n appli$ ov] ! pat*1 ea* coat be+ all[$ to dry be=e ! next is appli$4 ,,faults ,,9 ,,flight1 ,,due ,,to ,,improp] ,,alignm5t ,,& ,,h[ ,,to ,,correct ,,!m ,an airplane pilot may exp]i5ce difficulty ) ! fly+ qualities ( 8 ma*9e4 ,consequ5tly he %\ld "k some?+ ab\t ! conditions :i* are responsible = ! v>i\s k9ds ( unsatisfactory fly+ qualities :i* are m or less *>act]i/ic ( airplanes4 ,9 ! *apt] on 8,pr9ciples ( ,flight0 ! read] has be5 made acqua9t$ ) su* t]ms z /ability1 in/ability1 longitud9al /ability1 etc4 ,= ! purposes ( rigg+1 h[ev]1 x w be well to review ^! t]ms aga94 ,/ability is a condition :]eby an object di/urb$ has a natural t5d5cy to return to its fir/ & normal position4 ,example3 a weight susp5d$ by a cord4 ,in/ability is a condition :]eby an object di/urb$ has a natural t5d5cy to move z f> z possible away f its fir/ position1 ) no t5d5cy to return4 ,example3 a /ick balanc$ v]tically on y\r f+]4 ,neutral /ability is a condition :]eby an object di/urb$ has no t5d5cy to move f>!r ?an displac$ by ! =ce ( ! di/urbance1 & no t5d5cy to return to its fir/ position4 ,n[ 9 ord] t an airplane may be reasonably controllable1 x is necess>y = x to possess "s degree ( /ability longitud9ally1 lat]ally & indirectionally4 ,longitud9al /ability is its /ability ab\t an axis transv]se to ! direction ( normal horizontal flight1 & )\t :i* x w\ld pit* & toss4 ,lat]al /ability is its /ability ab\t its longitud9al axis1 & )\t :i* x w\ld roll sideways4 ,directional /ability is its /ability ab\t its v]tical axis1 & )\t :i* x w\ld h no t5d5cy to keep its c\rse4 ,:5ev] an airplane does n fly prop]ly1 aside f conditions aris+ f eng9e or propell] tr\ble1 ei!r its longitud9al1 lat]al1 or directional /ability is affect$4 ,:5 its longitud9al /ability is affect$ we call ?is condition longitud9al in/ability2 likewise1 reg>d+ lat]al /ability & directional /ability1 ref]r+ to ^! conditions respectively z lat]al & z directional in/ability4 ,! effect ( alignm5t errors w be treat$ "u ! =ego+ respective heads4 ,alignm5t ,errors1 ,longitud9al4-- #a4 ,! ,/agg] ,may ,be ,wrong4--,! top surface or w+ may h drift$ back a little ow+ to "s ( ! wires1 probably ! incid5ce wires1 hav+ elongat$ _! loops or hav+ pull$ ! fitt+s into ! wood4 ,if ! top surface is n /agg]$ =w>d to ! correct am\nt1 !n consequ5tly ! :ole ( its lift is too f> back1 & x w !n h a t5d5cy to lift up ! tail ( ! ma*9e too mu*4 ,! airplane w !n be said to be nose-heavy4 ,a -94 error 9 ! /agg] w make a v consid]able diff]5ce 9 ! longitud9al /ability4 #b4 ,! ,angle at ,:i* ! ,ma9 ,surfaces ,are ,set ,relative to ! ,fuselage ,may ,be ,wrong4--,?is w h a bad effect especially 9 ! case ( an airplane ) a lift+ tail plane or horizontal /abiliz]4 ,if ! angle ( incid5ce is too great1 ! ma*9e w h a t5d5cy to fly 8tail-high40 ,if ! angle is too small ! airplane may h a t5d5cy to fly 8tail-d[n40 #c4 ,! ,fuselage ,may ,h ,become ,w>p$ ,upw>d or ,d[nw>d4--,?is w\ld give ! tail plane or horizontal /abiliz] an incorrect angle ( incid5ce4 ,if x has too mu* angle1 x w lift too mu*1 & ! airplane w be 8nose-heavy40 ,if x has too little angle1 x w n lift en\gh & ! airplane w be 8tail-heavy40 #d4 ,! ,tail ,plane ,may ,be ,m\nt$ ^u ! ,fuselage at a ,wrong ,angle ( ,incid5ce4--,if ?is condition exi/s1 x mu/ be correct$ by mak+ a *ange at ! fitt+s4 ,if nose-heavy1 ! tail plane %\ld be giv5 a small] angle ( incid5ce4 ,if tail-heavy1 x %\ld be giv5 a great] angle ( incid5ce2 b c>e %\ld be tak5 n to give x too great an angle1 because ! longitud9al /ability entirely dep5ds ^u ! tail plane be+ set at a small] angle ( incid5ce ?an is ! ma9 surface1 & if t diff]5ce is decreas$ too mu*1 ! airplane w become uncontrollable longitud9ally4 ,sometimes ! tail plane is m\nt$ on ! airplane at ! same angle z ! ma9 surface1 b x actually engages ! air at a less] angle1 ow+ to ! air be+ deflect$ d[nw>d by ! ma9 surfaces4 ,alignm5t ,errors1 ,lat]al4--,! ma*9e manife/s a t5d5cy to fly "o w+ d[n4 ,! reason = su* a condition is a diff]5ce 9 ! lifts ( ! "r & left w+s1 assum+ ! motor torque is already tak5 c>e ( by wa%\t4 ,t may be caus$ z foll[s3 #a4 ,! ,angle ( ,incid5ce ( ,"o ,w+ ,may ,be ,wrong4--,if x is too great1 x w produce m lift ?an on ! o!r side ( ! airplane2 & if too small1 x w produce less lift ?an on ! o!r side--) ! result1 9 ei!r case1 ! airplane w try to fly "o w+ d[n4 #b4 ,di/ort$ ,surfaces4--,if "s "p ( ! surface is di/ort$1 ! lift w n be ! same on bo? sides ( ! airplane1 :i*1 ( c\rse1 w aga9 cause x to fly "o w+ d[n4 #c4 ,! ,ail]ons ,may ,be ,set ,slightly ,wrong4--,?is may be due to "o control cable be+ long] ?an ! o!r1 or "o ( ! ail]on horns be+ b5t or twi/$4 ,?is condition c easily be detect$ by sett+ ! ail]on control--9 neutral & *eck+ up ! position ( ! ail]ons4 ,alignm5t ,errors1 ,directional4--,if !re is m resi/ance on "o side ( ! airplane ?an on ! o!r ! airplane w1 ( c\rse1 t5d to turn to ! side hav+ ! mo/ resi/ance4 ,?is may be caus$ by ! foll[+ conditions3 #a4 ,! ,angle ( ,incid5ce ( ! ,"r & ,left ,surfaces ,may ,be ,unequal4--,! great] ! angle ( incid5ce1 ! great] ! resi/ance4 ,! less ! angle1 ! less ! resi/ance4 #b4 ,if ! ,alignm5t ( ! ,fuselage1 ,v]tical ,/abiliz]1 ! ,/ruts or ,/ream-l9e ,wires ,is ,n ,absolutely ,correct4--,t is to say1 if !y are turn$ a little to ! "r or left in/ead ( be+ 9 l9e ) ! direction ( flight--!n !y w act z a rudd] & cause ! airplane to turn (f its c\rse4 #c4 ,if ,any ,"p ( ! ,surface ,is ,di/urb$ ,x ,w ,cause ! ,airplane to ,turn (f ,its ,c\rse4--,if1 ow+ to ! lead+ edge1 sp>s1 or trail+ edge becom+ b5t1 curvature is spoil$1 t w result 9 *ang+ ! am\nt ( resi/ance on "o side ( ! airplane1 :i* w !n develop a t5d5cy to turn (f its c\rse4 ,additional ,flight ,defects4--,9 addition to ! =ego+ ! foll[+ conditions may also exi/ :i* cause tr\ble :5 fly+ z well z :5 l&+3 ,airplane ,climbs ,badly4--,su* a condition1 ap>t f eng9e or propell] tr\ble1 is probably due to excess resi/ance some:]e4 ,flight ,spe$ ,poor4--,?is condition ap>t f eng9e or propell] tr\ble1 is probably due to 7#a7 di/ort$ surfaces1 7#b7 wrong angle ( incid5ce1 or 7#c7 dirt or mud1 result+ 9 excessive sk9 friction & weight4 ,ineffici5t ,control4--,?is is probably due to 7#a7 wrong sett+ ( ! control surfaces1 7#b7 di/ortion ( control surfaces1 or 7#c7 control cables be+ badly t5sion$4 ,w ,n ,taxi ,/raight4--,if ! airplane is uncontrollable on ! gr\nd x is probably due to 7#a7 alignm5t ( ! und]c>riage be+ wrong1 7#b7 unequal t5sion ( %ock absorb]s1 7#c7 tires unequally inflat$1 7#d7 axle b5t1 7#e7 tight :eel & axle1 7#f7 loose spokes caus+ :eel to wobble4 ,,*apt] ,,ix ,,tru+ ,,up ,,! ,,fuselage ,be=e an airplane is assembl$ = ! fir/ "t aft] leav+ ! factory1 & especially aft] x has made its fir/ few 8break+-90 flights1 ! fuselage or basic framework %\ld be c>efully exam9$ & *eck$ up4 ,?is is done 9 ord] to det]m9e :e!r or n ! fuselage became di/ort$ f r\gh usage dur+ %ipm5t 7:i* is always likely7 or f tak+ sets due to ! fly+ /resses to :i* x 0 subject$ = ! fir/ "t dur+ ! 8break+-90 flights4 ,x frequ5tly happ5s t r\gh l&+s & 8/unt0 fly+ cause di/ortions ( ! fuselage frame & o!r p>ts ( ! airplane s t x is v necess>y to make a c>eful inspection imm$iately aft] to asc]ta9 n only :at twi/s1 b[s & /ret*+ ( vital p>ts h result$1 b also to detect fitt+s1 wires1 etc41 :i* may h be5 pull$ loose or brok54 ,! extreme importance ( hav+ y\r airplane adju/$ correctly & c>efully1 & to "k t x is 9 ! prop] condition c n be reit]at$ too (t54 ,&1 s9ce ! fuselage is ! f\ndation f :i*1 s to speak1 ! entire app>atus is built up1 x is d\bly important t x %\ld always be 9 correct adju/m5t4 ,:5 ! fuselage is built 9 ! factory x is plac$ on a long table ^: surface is p]fectly horizontal & :i* has metal /rips inlaid4 ,?is table 9 reality is a big face plate especially arrang$1 z describ$1 = fuselage tru+ 9 ! factory4 ,! fuselage1 ( c\rse1 has _h none ( its cov]+s appli$ :5 x is plac$ on ! table1 nor are ! accessories su* z controls & eng9e 9 place4 ,on ?is table !n ! build]s beg9 to d ! necess>y adju/+ & ?is is no simple or quick job4 ,work+ f a p]fectly smoo? horizontal surface x is1 ( c\rse1 easy to detect w>p+s1 twi/s1 etc41 ( ! framework4 ,^! are fir/ rem$i$ by tight5+ or loos5+ ( cross wires1 etc41 z ! case may be4 ,!n1 :5 ! fuselage is reasonably squ>e & level1 l5g?wise & crosswise1 z det]m9$ by ! eye1 *eck measurem5ts are tak5 by rule1 trams & level & f9al adju/m5ts made to br+ ! v>i\s p>ts 9 f9al prop] relation to "o ano!r4 ,= in/ance1 ! rudd] po/ mu/ be p]fectly v]tical1 z det]m9$ by a plumb l9e1 :5 ! eng9e be>]s or ! top long]ons are level4 ,! v>i\s fitt+s su* z ^? = horizontal & v]tical /abiliz]s & ! eng9e sections & side panels mu/ all con=m accurately to "o ano!r s t ! airplane z a :ole1 :5 x is assembl$1 w n conta9 any inh]5t defects su* z tail planes ) slightly di/ort$ angles ( incid5ce1 left ma9 panels ahead ( "r or ov] or "u "r ma9 panels1 fitt+s s locat$ t an initial /ra9 mu/ be impos$ ^u !m by =c+ !m toge!r1 etc4 ,aft] ! fuselage has be5 l9$ up 9 ! factory z describ$ briefly above1 x is p]mitt$ to set = a week or s & !n x is *eck$ up aga9 & su* additional slight corrections made :i* w\ld be necessitat$ by ! sets :i* _h occurr$4 ,! additional fitt+s requir$ are !n appli$ & ! fuselage f9ally cov]$ & s5t away to h ! eng9e & in/rum5ts appli$4 ,:5 *eck+ & tru+ a fuselage on ! fly+ field aft] ! airplane has be5 assembl$ & fl[n ! process is n q s simple z :5 ! fuselage is *eck$ up & tru$ 9 ! factory1 l>gely ow+ to ! lack ( ideal factory facilities & also because s _m fitt+s1 cov]+s1 etc41 are 9 ! way :i* "o mu/ always be cauti\s ab\t remov+4 ,9 g5]al1 ! me?od ( proc$ure may be outl9$ z foll[s1 b x mu/ be obvi\s t "o c n 9 a s]ies ( writt5 notes t\* ^u all ! possible qu]ies & comb9ations ( fuselage di/ortions :i* may occur & ! ways = detect+ & correct+ !m4 ,a c]ta9 am\nt ( exp]i5ce 9 ! field accompani$ ) "s fix$ habits ( inspection1 & ev]la/+ curiosity ab\t ! p]fections ( y\r ma*9e1 & a will+ness & read9ess always to pit* 9 & help correct ! defects f\nd1 w soon develop 9 y ! ability to diagnose easily & quickly & rem$y intellig5tly :atev] tr\ble y may run across4 ,= satisfactory fuselage *eck+ & tru+ let u say 9 ! field %op1 a c]ta9 m9imum equipm5t ( tools is necess>y4 ,?is equipm5t is3 ,at lea/ two sa:orses ab\t #c to #d ft4 high = m\nt+ ! fuselage 9 fly+ position4 ,sev]al wood5 w$ges 7%[ tap]7 = easy adju/m5t ( fuselage = cross & l5g?wise level4 ,ab\t #be yd4 ( /rong l95 l9e = *eck+ c5t] l9es4 #b c>p5t] levels ab\t #b to #c ft4 long4 #d p]fectly =m$ /eel cubes ab\t #a to #a 94 9 size4 #a plumb bob4 #a small screw jack4 #a pair ( wood clamps4 #a /raight edge ab\t #ab ft4 long4 ,sev]al small ,cresc5t adju/able wr5*es4 ,sev]al pli]s ) wire-cutt+ atta*m5t4 ,p9s = manipulat+ turnbuckles4 #a /eel tape4 #a foot rule1 #f ft4 long4 #a small brass hamm]4 ,a small "w b5* equipp$ ) a #c-;94 or #d-;94 vise4 ,! fuselage :i* is to be tru$ is m\nt$ on ! horse ) ! w$ges betwe5 ! top horse rails & ! l[] long]ons4 ,^! horses or tre/les %\ld be s arrang$ t ab\t ?ree-f\r?s ( ! fuselage t[>d ! tail /icks out unsupport$4 ,9 ?is way x w take1 z ne> z possible1 its normal fly+ position4 ,x is always desirable1 9 fact q necess>y1 especially :5 *eck+ a fuselage = ! fir/ "t1 to h ! airplane's specifications z well z a detail$ draw+ ( ! fuselage & an assembly ( ! airplane z a :ole available4 ,! reason = ?is1 ( c\rse1 is q obvi\s4 ,! eng9e be>]s & ! top long]ons are ! basic p>ts f :i* ! fuselage z a :ole is l9$ up4 ,consequ5tly ! fir/ ?+ :i* is done1 :5 inspect+ ! fuselage = alignm5t1 is to te/ ! tru? ( ^! p>ts4 ,?is is done by sight+ ! top long]ons l5g?wise to see if !y are b[$ d[nw>d1 upw>d1 inw>d or outw>d4 ,z ne> z possible ! fuselage is made level on ! tre/les4 ,! /eel blocks or cubes ref]r$ to 9 ! tool li/ above are plac$ on ! long]ons & ! /raight edge & level plac$ on ^!1 fir/ crosswise & !n l5g?wise4 ,a /r+ is /ret*$ ov] ! top ( ! fuselage t\*+ ! top cross braces & br\ght z close z possible to ! c5t] ( ^! pieces4 ,?is /r+ %\ld /ret* f ! rudd] po/ z f> =w>d z possible4 ,!n ! cross wires or diagonal brace wires are sight$ to see h[ close _! int]sections agree ) ?is c5t]-l9e /r+4 ,fur!rmore1 ! level is plac$ on ! eng9e be>]s & !y are te/$ = cross level & longitud9al level4 ,if ! eng9e is m\nt$ 9 place1 b "o po9t on ! be>]s w be available = ?is purpose1 b ! *eck %\ld nev]!less be made4 ,x may also be f\nd t ! longitud9al level ( ! eng9e be>]s c be te/$ f und]nea? by plac+ ! /eel cubes m5tion$ above on ! top ( ! level & !n hold+ ! level up aga9/ ! bottom ( ! be>]s4 ,z a rule1 if ! fuselage is w>p$ x %\ld be possible to detect ?is ) ! eye1 b :5 eng9e be>]s are out ( l9e ?is c only be detect$ ) c]ta9ty by ! use ( ! level4 ,let x be assum$ t ! fuselage is out ( true4 ,! fir/ p>ts to tackle are1 ( c\rse1 ! eng9e be>]s4 ,if !y %\ld n be 9 l9e !y mu/ fir/ be br\ght s1 & aft]w>d kept 9 ?is condition4 ,! diagonal wires at ! front ( ! fuselage %\ld be adju/$ to make ?is correction4 ,if ! be>]s are badly out ( l9e x w1 p]haps1 be wise/ to remove ! eng9e1 or at lea/ loos5 x up f ! be>]s be=e do+ any adju/+ = ! reason t x may become /ra9$ by s]i\s pull+ on ! be>]s4 ,aft] ! be>]s are 9 place1 x w be safe to bolt ! eng9e fa/ aga94 ,) ! eng9e be>]s tempor>ily dispos$ (1 ! fuselage prop] is tackl$4 ,"h ! fir/ ?+ to d is to get ! top surfaces ( ! long]ons level crosswise4 ,use ! _s level & ! two /eel cubes m5tion$ 9 ! tool li/ = ?is purpose4 ,/>t at ! front ( ! fuselage 9 ! cock pit4 ,adju/ ! int]nal diagonal wires until ! level bubble is 9 its prop] place4 ,!n measure ^! fir/ two sets ( diagonal wires1 gett+ !m ( equal l5g?4 ,cont9ue ?is process ?r\gh\t ! l5g? ( ! fuselage until ! re> end is rea*$1 always work+ f ! front4 ,la/ly1 be=e proce$+ to ! next op]ation1 try ! eng9e be>]s = level aga94 ,if out1 make ! prop] adju/m5ts4 ,if ! c5t]s ( ! crosswise /ruts are n m>k$1 ?is %\ld fir/ be done be=e go+ fur!r4 ,!n /ret* a /r+ f ,no4 #a /rut1 or z f> =w>d z possible to ! c5t] ( ! rudd] po/4 ,all c5t] po9ts on ! cross /ruts1 if ! fuselage is true l5g?wise1 %\ld lie exactly on ?is /r+4 ,if n1 adju/ ! horizontal diagonal wires1 top & bottom1 work+ f ! front1 until ! c5t]-l9e po9ts all agree4 ,always *eck by measur+ diagonal wires :i* are mates4 ,^! %\ld be ( equal l5g?4 ,if n1 "s wire 9 ! s]ies may be ov]/ress$4 ,9 ord] to pull ! c5t] po9ts on ! cross /ruts ov]1 always /op to analyze ! situation c>efully1 det]m9+ :i* are ! long diagonals & :i* ! %ort ones f ! way ! fuselage is b[$4 ,!n %ort5 ! long ones & ease (f on ! %ort ones1 be+ c>eful nev] to ov]/ress any ( ! wires4 ,! la/ ?+ to d is to br+ ! long]ons or ! c5t] l9e ( ! fuselage into level l5g?wise4 ,= ?is purpose a long /raight-edge1 ! two cubes1 & a _s level are ( advantage1 al?\gh simply /ret*+ a /r+ closely ov] ! top ( ! long]on may suffice4 ,!n z 9 ! case ( remov+ a crosswise b[ 9 ! fuselage1 "h too1 we manipulate ! outside up & d[n diagonal wires 9 br++ ! top long]ons into _! prop] level position l5g?wise1 always work+ f ! front4 ,aft] all ?is is done x is well to make "s ov]all *ecks ) /eel tape or trams to see h[ v>i\s fitt+s locat$ accord+ to ! draw+s1 agree ) "o ano!r4 ,s9ce !re is a "r & a left side1 di/ance betwe5 fitt+s on ^! sides may be comp>$4 ,&1 f9ally1 ! eng9e be>]s %\ld be tri$ aga94 ,9 %ort no opportunity %\ld be neglect$ to prove ! tru? ( ! fuselage z a :ole & 9 detail4 ,x might be po9t$ out t an excell5t "t to *eck ! fuselage is :5 eng9e is be+ remov$ or *ang$4 ,9 fact ?is "t 9 g5]al is a good "o to give ! airplane z a :ole1 a c>eful inspection4 ,aft] all ! necess>y corrections h be5 made & all ! p>ts ( ! fuselage br\ght into correct relation ) "o ano!r1 ! turnbuckles are safety wir$ & !n s]v$ ) tape to act z a f9al protection4 ,! l95 cov]+ is reappli$ if x _h previ\sly to be remov$ & ! level1 emp5nage wires1 panels etc41 are plac$ 9 position & align$ z po9t$ out 9 ! notes on assembly & alignm5t4 ,,*apt] ,x ,,h&l+ ,,( ,,airplanes ,,9 ,,! ,,field ,,& ,,at ,,! ,,bases ,,previ\s ,,to ,,& ,,aft] ,,flights ,no unimportant "p ( ! op]ation & ma9t5ance ( airplanes is _! h&l+ 9 ! field1 & at ! v>i\s bases previ\s to1 betwe51 & aft] flights4 ,?is phase ( ! entire subject contemplates ! transportation ( airplanes 9 knockd[n condition ei!r by railway or truck1 _! unload+ & unpack+1 to a c]ta9 ext5t _! assembly1 _! /orage 9 hang>s & %$s1 _! /orage & disposition 9 ! op51 _! disassembl+ & pack+ = transportation1 etc4 ,! ,unload+ & ,unpack+ ( ,airplanes4--,! p]sonnel requir$ to unload an airplane prop]ly box$ & crat$ f a railway c>1 is #ae m5 & two non-commission$ (fic]s4 ,! tools ne$$ = ?is purpose are3 #a ax4 #b cr[b>s4 #f l5g?s ( iron pipe ab\t #b 94 9 diamet]1 #c ft4 long4 #f l5g?s ( iron pipe ab\t #b 94 9 diamet]1 #d ft4 long4 #ajj ft4 manila rope1 #a 94 9 diamet]4 ,a regul> flat-b$ mov+ truck or ord9>y truck ) a flat-b$ trail] %\ld be provid$ = h&l+ ! ma*9e f ! c> to ! field erect+ %op4 ,airplanes are usually %ipp$ 9 automobile c>s ) end doors or gondola c>s4 ,aft] op5+ doors ( c>s1 exam9e & inspect all crates & boxes c>efully to see t !y are all !re 9 accordance ) ! bill ( load+ or %ipp+ memor&um1 z well z to see t !y are 9 good condition4 ,if any boxes are f\nd damag$1 !y %\ld n be remov$ f ! c> )\t fir/ report+ ! fact to ! receiv+ (fic]4 ,next1 all cleats & brac+ %\ld be remov$4 ,! crate conta9+ ! fuselage & eng9e %\ld1 if possible1 be unload$ fir/4 ,! heavy end :]e ! eng9e is fix$ %\ld be lift$ up1 h #b-;94 pipe roll]s put und]nea? & manipulat$ into ! truck :i* has be5 back$ up aga9/ ! c> door s t ?is heavy end1 :5 f9ally plac$1 w re/ on ! body ( ! truck z f> =w>d z possible4 ,next la% ! front end ( ! box securely to ! truck4 ,%\ld x happ5 t ! fuselage crate is s locat$ 9 ! c> t ! light end mu/ ( necessity em]ge fir/ ?r\gh ! door1 !n ?is end may be run on to a truck & ! crate remov$ f ! c> ) ! heavy end adequately support$ by suffici5t help4 ,ano!r truck is !n back$ up aga9/ ! re> ( ! fir/ "o :i* has be5 mov$ into ! cle>1 & ! heavy end ( ! fuselage crate br\ght to re/ z f> =w>d z possible 9 ! second truck4 ,x is !n secur$ & ! fir/ truck releas$4 ,aft] ! box is prop]ly la%$ by means ( ! manila rope1 a man %\ld be plac$ on ea* side ( x to wat* & see t ! la%+s d n loos5 & ! box %ift 9 transit4 ,trucks %\ld be driv5 sl[ly1 especially ov] r\gh gr\nd1 tracks1 etc4 ,9 addition to ! fuselage crate x may also be possible to load ! panel crates on ?is same truck1 b z a rule x is bett] to load ^! on a second truck4 ,common s5se goes a long way 9 transport+ aircrafts by motor trucks4 ,unload+ ( ! crates is done ) ! use ( skids appli$ to ! re> ( ! truck & secur$ s z to =m a sort ( an incl9$ plane d[n :i* to slide ! boxes on ! pipe roll]s to ! gr\nd4 ,^! skids %\ld be at lea/ #d 94 by #d 94 by #f ft4 & made ( /rong wood4 ,! re> end ( ! crate may be br\ght to ! gr\nd1 re/$ !re1 & ! truck mov$ =w>d sl[ly until ! entire l5g? re/s on ! gr\nd4 ,c>e mu/ be us$ n to jolt or drop ?is box at any /age :atsoev]4 ,:5 uncrat+ ! fuselage1 remove ! top & bo? ends ( ! box4 ,fold bo? sides ( box flat d[n on gr\nd & use same = assembl+ ma*9e4 ,! w+ boxes %\ld h ! tops remov$ & planes lift$ out 9 t mann]4 ,next1 ! airplane is assembl$ 9 accordance ) in/ructions already giv54 ,! ,dismantl+ & ,load+ ( ,airplanes4--,:5 airplanes are to be prep>$ = %ipm5t by motor truck or railway1 !y %\ld1 ( c\rse1 be tak5 d[n & crat$ simil> to ! way !y 7 %ipp$ f ! factory4 ,! ord] 9 :i* ?is is done %\ld be z foll[s3 ,remove propell]4 ,unfa/5 control wires4 ,unfa/5 ma9 planes f fuselage & dismantle on gr\nd4 ,remove tail surfaces4 ,unless ma*9e is to be plac$ 9 box1 l&+ ge> & tail skid %\ld rema9 atta*$ to fuselage4 ,if ! ma*9e is crat$ x %\ld be h&l$ :5 %ipp$ ! same z describ$ above4 ,if1 h[ev]1 x is to be load$ )\t be+ crat$1 !n ! foll[+ proc$ure %\ld be obs]v$4 ,us+ two planks1 #b 94 by #ab 94 by #ah ft4 long = runway f gr\nd into c>1 load ma*9e into c>1 eng9e fir/4 ,block :eels to prev5t ma*9e %ift+4 ,secure fuselage1 tail end1 to ! floor ( ! c> by means ( ropes pass$ ov] ! fuselage & fa/5$ to ! floor ) cleats4 ,! w+s %\ld be crat$ aga9/ ! sides ( c> & secur$ by wires1 ropes or canvas /rips4 ,all boxes %\ld be m>k$ ) "n ( organization1 de/9ation1 weight1 cubic cont5ts1 hoi/+ c5t]s1 numb] ( box1 8,?is ,side ,up10 etc4 ,a %ipp+ memor&um %\ld always be made out & mail$ to de/9ation :5 %ipm5t goes =?4 ,/or+ ( ,airplanes & ,p>ts at ,bases & 9 ,fields4--,airplanes :5 n 9 active fly+ duty are /or$ 9 hang>s or %$s especially adapt$ to h\se !m4 ,"u c]ta9 conditions x is necess>y to /ore !m 9 ! op54 ,9 ea* case p>ticul> precautions %\ld be obs]v$ 9 ord] n to subject ! ma*9es to unnecess>y we> & te>4 ,s9ce moi/ure is "o ( ! airplanes' wor/ enemies 9 t x det]iorates ! wea!rpro(+ & ! fabric1 di/orts & o!rwise injures ! wood5 p>ts ( ! ma*9es & wor/ ( all1 ru/s ! metal p>ts1 ! fir/ consid]ation = prop] /orage facilities %\ld be ! abs5ce ( moi/ure4 ,next1 extreme heat & cold are a m5ace to airplanes4 ,! temp]ature ( ! air surr\nd+ !m :ile 9 /orage %\ld be regulat$ z mu* z possible4 ,"u %elt]1 especially :5 ! ma*9e is to be out ( active s]vice = #dh hr4 or m1 ! entire ma*9e %\ld be rais$ (f ! gr\nd a few in*es s t ! :eels are free & ! flexible connections releas$4 ,?is is done by ! po9ts :]e ! und]c>riage /ruts meet ! skids4 ,fur!rmore1 ! w+s might well be support$ & ! weight ?us tak5 (f ! l&+ wires1 & h+e connections by plac+ padd$ tre/les und]nea? ! w+ skids4 ,c>e %\ld be ex]cis$ t dirt1 grease1 wat]1 etc41 does n accumulate 9 any "p ( ! airplane4 ,fur!rmore1 all wat] %\ld be dra9$ f ! radiator & gasol9e f ! gasol9e tank4 ,! propell] %\ld be plac$ 9 a v]tical position & cov]$ ) a wea!rpro( clo?4 ,! eng9e cockpit & in/rum5ts %\ld all be cov]$ & ! magneto %\ld be enclos$ 9 a ?ick lay] ( felt or cotton wa/e4 ,if any fluid is apt to freeze1 & oil w freeze 9 temp]atures l[ en\gh1 x %\ld be c>efully dra9$4 ,:5 sp>e p>ts su* z w+s1 /ruts1 fuselages1 etc41 are /or$1 ! same g5]al precautions outl9$ above %\ld be obs]v$4 ,sp>e planes p>ticul>ly %\ld be plac$ 9 su* a mann] t _! weight is ev5ly support$4 ,nev] %\ld planes ( any k9d be laid flat on ! gr\nd4 ,!y %\ld always /& edgewise1 ) ! lead+ edge d[n1 support$ sev]al in*es (f ! gr\nd on blocks or bo>ds ev5ly spac$4 ,"o plane mu/ n be all[$ to lean aga9/ ano!r4 ,9 fact1 ! be/ way is to susp5d planes by means ( canvas sl+s hung f ov]head4 ,)9 ! loop ( ! sl+s !re mu/ be a batt5 ab\t #b 94 wide4 ,all p>ts ( an airplane subject to attack by ru/ %\ld be kept well coat$ ) grease or oil4 ,p]iodically ! entire ma*9e %\ld be wip$ by means ( clean1 dry *eese clo? or select$ cotton wa/e4 ,eng9es :i* are 9 /or$ planes or :i* h be5 set aside = future use %\ld be turn$ ov] by h& daily4 ,x w sometimes be impossible = airplane %$s or hang>s to be br\ght up to ! front on s]vice1 h5ce1 airplanes mu/ be prep>$ to rema9 9 ! op54 ,:5 ?is is ! case !y %\ld be plac$ to ! leew>d ( ! highe/ h$ge available1 a clump ( trees1 a build+1 a bank1 a knoll1 or hill1 etc4 ,!y %\ld be sunk z l[ z possible by digg+ a tr5* = ! :eels & und]c>riage4 ,! nose ( ! plane %\ld1 ( c\rse1 fir/ be run into ! w9d1 & !n ! w+s & ! tail pegg$ d[n ) ropes1 p>ticul>ly if !re is any *ance ( a w9d />t+ up4 ,! eng9e1 propell]1 in/rum5ts1 & cockpit %\ld be cov]$ ov] ) a wat]pro( clo? & great c>e tak5 to protect ! propell] f ! sun1 = x w surely w>p if n c>$ = prop]ly4 ,at night 9 cold or wet wea!r ! magneto %\ld be pack$ r\nd ) wa/e & wat] 9 ! radiator dra9$4 ,:ile ma*9es are /or$ 9 ! op51 ! necessity ( wip+ !m to keep !m moi/ure & dirt free is all ! m urg5t & %\ld be pursu$ ) d\bl$ en]gy4 ,,*apt] ,,xi ,,inspection ,,( ,,airplanes ,me*anics 9 *>ge ( airplanes1 :o are prim>ily responsible = _! safety :ile 9 _! c>e1 %\ld con/antly ?9k ( new me?ods = insur+ great] safety & reliability4 ,!y %\ld inv>iably br+ any fre% po9ts !y ?9k ( to ! att5tion ( _! ,flight ,comm&]1 9 ord] t ! re/ ( ! ,corps may b5efit by !m4 ,!y %\ld always try to f9d out ! cause ( any?+ wrong1 & in=m ! (fic] 9 *>ge ( ! ma*9e ( _! op9ion4 ,!y %\ld be> 9 m9d any p>ticul> incid5ts :i* may h happ5$ to _! ma*9e :ile "u _! *>ge dur+ ea* flight1 & be on ! look\t = signs ( /resses t may h occurr$ to ! ma*9e 9 consequ5ce ( ^! incid5ts4 ,= example1 a /eep spiral may cause side /ra9s on ! eng9e be>]s2 a flight 9 bad wea!r may cause b5d+ /resses on ! longitud9al memb]s ( ! body1 besides /ret*+ ! l&+ & fly+ wires4 ,no "p ( a ma*9e c be safely ov]look$1 & good me*anics w always be seek+ = ! possible cause ( accid5ts & br++ !m to ! notice ( ! (fic] 9 *>ge ( ! ma*9es4 ,dur+ all inspections ! foll[+ matt]s ( detail des]ve p>ticul> att5tion3 ,look out = dirt1 du/1 ru/1 mud1 oil on fabric4 ,cleanl9ess is ! v fir/ consid]ation4 ,give ! control cables p>ticul> att5tion4 ,^! %\ld n be too tight1 o!rwise !y w rub /iffly 9 ! guides4 ,! h& %\ld be pass$ ov] !m to detect k9ks & brok5 /r&s4 ,!y %\ld be especially well exam9$ :]e !y run ov] pulley4 ,don't =get ! ail]on balance wire on ! top plane4 ,see t all wires are well greas$ & oil$1 & t !y are all 9 ! same t5sion4 ,:5 exam9+ wires1 be sure to h ma*9e on level gr\nd z o!rwise x may get twi/$1 ?r[+ "s wires into undue t5sion & slack5+ o!rs4 ,! be/ way1 if "t is available1 is to jack ! airplane up into 8fly+ position40 ,if a slack wire is f\nd1 d n jump to ! conclusion t x mu/ be t5sion$4 ,p]haps its opposite wire is too tight1 9 :i* case x %\ld be slack5$4 ,c>efully exam9e all wires & _! connections ne> ! propell]1 & be sure t !y are snak$ ar\nd ) safety wire1 s t ! latt] may keep !m out ( ! way ( ! propell] if !y come adrift4 ,c>efully exam9e all surfaces1 includ+ ! controll+ surfaces1 to see :e!r any di/ortions h occurr$4 ,if di/ortions c be correct$ by adju/m5t ( wires1 well & good1 b if n1 matt] %\ld be report$4 ,v]ify ! angles ( incid5ce1 ! dih$ral angle1 ! /agg]1 & ! ov]all measurem5ts z (t5 z possible 7at lea/ once a week7 & correct z outl9$ 9 notes on assembly & adju/m5t ( airplanes4 ,con/antly exam9e ! alignm5t & fitt+s ( ! und]c>riage1 ! condition ( tires1 %ock absorb]s & ! skids4 ,v]ify ! rigg+ position ( ! ail]ons & elevators4 ,con/antly inspect ! lock+ arrangem5ts ( ! turnbuckles1 bolts1 etc4 ,le>n to become an exp]t at vett+1 :i* means ! ability to judge ! alignm5t ( ! airplane & its p>ts by eye4 ,:5ev] y h ! opportunity practice sight+ "o /rut aga9/ ano!r to see t !y are p>allel4 ,/&+ 9 front ( ! ma*9e1 :i* 9 su* a case %\ld be on level gr\nd1 sight ! c5t] section plane aga9/ ! tail plane & see t ! latt] is 9 l9e4 ,sight ! lead+ edge aga9/ ! ma9 sp>s1 ! re> sp>s1 & ! trail+ edges1 tak+ into consid]ation ! 8wa%90 & 8wa%\t40 ,y w be able to see ! %ad[ ( ! sp>s ?r\gh ! fabric4 ,by practis+ ?is sort ( ?+ y w1 aft] a "t1 become q exp]t1 & w be able to diagnose by eye faults 9 effici5cy1 /ability & control4 ,! foll[+ ord] %\ld be obs]v$ 9 ! daily & weekly inspections3 ,daily ,inspection4--,all /ruts & _! sockets1 long]ons1 skids1 etc4 ,all outside wires & _! atta*m5ts4 ,all control lev]s or :eels1 control wires & cable & _! atta*m5ts4 ,all splices = any signs ( _! draw+4 ,lift & l&+ ge> cables or wires = any signs ( /ret*+4 ,all fabrics1 :e!r on w+s or o!r p>ts ( ! ma*9e1 = holes1 cuts1 weak or badly dop$ places1 or signs ( be+ soak$ ) gasol9e1 & to see if prop]ly fa/5$ to w+s1 etc4 ,all outside turnbuckles1 to see t !y h suffici5t ?reads engag$1 & t !y are prop]ly lock$4 ,axles1 :eels1 %ock absorb]s1 & tires1 pump+ ! latt] up to ! correct pressure4 ,! seats1 bo? = pass5g] & pilot1 see+ t !y are fa/5$ correctly4 ,safety belts & _! fa/5+s4 ,?is exam9ation %\ld be c>ri$ out sy/ematically 9 ! foll[+ ord]3 7a7 ,l[] w+s1 l&+ ge> complete1 tail planes ) all wires atta*$ to ^! tail skids & all atta*m5ts & rudd]4 7b7 ,nacelle or fuselage1 bolts ( l[] plane1 all control lev]s & wires4 7c7 ,top w+s1 w+ flaps or ail]ons & wires4 ,inspection aft] ,ea* ,flight4--,! l&+ ge>1 tail skid & atta*m5ts & lift & drag wires = tautness4 ,! :eels1 aft] a r\gh l&+1 = b5t spokes1 uncov]+ !m if necess>y4 ,aft] fly+ is f9i%$ = ! day1 wipe all oil (f ! planes z f> z possible ) a clo? or cotton wa/e4 ,weekly ,inspection4--,*eck ov] all dim5sions1 span1 *ord1 gap1 /agg] ( w+s1 angles ( incid5ce or set angle ( w+s & tail1 dih$ral angle1 alignm5t ( fuselage1 rudd]1 elevators1 & ! g5]al tru? ( ! ma*9e4 ,exam9e ! po9ts ( cross+ ( all wires to see t !re are no signs ( we>1 & t ea* wire is prop]ly b\nd ) insulat+ tape to prev5t rubb+4 ,exam9e all places :]e wires cross ! /rut to see if ! plates require r5ewal4 ,exam9e any control wires :i* are b\nd toge!r1 & see t !y are correct4 7,insulat+ tape %\ld be us$ = ?is 9 pref]5ce to wires :i* are b\nd to slip & cause slack47 ,exam9e ! :eels = b5t or loose spokes1 uncov]+ if necess>y4 ,exam9e all nuts & bolts ( cott]-p9 applications1 lock wa%]s1 etc4 ,! foll[+ directions = inspection are giv5 to ! ,u4 ,s4 ,inspectors ( ,airplanes3 ,inspection ( ,cables4 ,are !re any k9ks 9 ! cable8 ,are loops prop]ly made8 ,are ?imbles us$ 9 eyes8 ,are ends wrapp$ prop]ly 7:5 wrapp$ splice is us$1 wrap mu/ be at lea/ fifte5 times ! diamet] ( wire74 ,no splic+ ( ! cable itself is p]mitt$4 ,has acid /ruck cable dur+ sold]+8 ,are any ( ! /r&s brok58 ,are unwrapp$ ends /ream-l9$ & %[ ! result ( skill$ workman%ip8 ,= ,roebl+ ,h>d ,wire4 ,are !re any file cuts or flaws to weak5 x8 ,is loop well made8 ,is f]rule put on correctly8 ,are !re any %>p b5ds or k9ks8 ,are wires too loose or tight 9 ma*9e8 ,fitt+s4 ,is workman%ip good8 ,is mat]ial good8 ,are holes drill$ correctly to develop prop] /r5g?8 ,are !re any deep file cuts or flaws to weak5 x8 ,is rivet or fa/5+ wire put 9 prop]ly8 ,are ?imbles ( l>ge en\gh diamet]8 ,turnbuckles4 ,any file cuts1 tool m>ks1 or flaws 9 %ank or b>rel8 ,are !re too _m ?reads expos$8 ,is turnbuckle ( "r /r5g? & size to develop full /r5g? ( wire8 ,are %anks b5t8 ,are ?reads on %ank or 9 b>rel well made8 ,is b>rel crack$8 ,is turnbuckle prop]ly wir$8 ,inspection ( ,l954 ,all l95 us$ 9 airplane con/ruction %\ld be ( ! foll[+ specifications3 ,free f all knots or k9ks4 ,)\t siz+ or fill+4 ,z ne> :ite z possible4 ,weight1 betwe5 #c4e & #d4e oz4 p] squ>e y>d4 ,/r5g? z p] ,gov]nm5t ,specifications4 ,inspection ( ,wood4 ,all wood %\ld be inspect$ be=e v>ni% is appli$4 ,is gra9 satisfactory8 ,are !re any sap or worm holes8 ,are !re any knots t look z if !y w\ld weak5 ! memb]8 ,any bra%9ess8 ,any holes drill$ = bolts or screws t w\ld weak5 ! memb]8 ,any splits or *ecks8 ,are lam9ations glu$ prop]ly8 ,are !re any plugg$ holes8 ,any signs ( dry rot8 ,inspection ( ,metal ,fitt+s4 ,:5 fitt+s are copp] plat$ & japann$ ! inspection %\ld take place aft] ! copp] plat+4 ,h fitt+s be5 b5t 9 assembl+8 ,does fitt+ %[ any defects t less5 its /r5g?8 ,are holes drill$ prop]ly4 ,d fitt+s fit8 ,%eet alum9um %\ld be inspect$ = defects su* z cracks1 bad d5ts1 etc4 ,:]e op5+s occur 9 %eet alum9um ! corn]s %\ld be r\nd$1 all[+ a good-siz$ radius4 ,directions = ,"w4 ,be=e y />t "w on rigg+ y are advis$ z foll[s3 #a4 ,d n hurry ab\t ! "w4 ,no ru% jobs c be done 9 airplane rigg+4 #b4 ,y are caution$ aga9/ leav+ tools ( any k9d 9 any "p ( ! airplane4 #c4 ,! bolts & _! ?reads mu/ n be burr$ 9 any way2 = ?is reason1 ! use ( pli]s or pipe wr5*es on bolts is v bad =m4 #d4 ,/>t all turnbuckles f bo? ends e "t !y are connect$ up4 #e4 ,full ?reads mu/ be _h 9 e case to develop ! full /r5g? ( a bolt & nut1 ) turnbuckles at lea/ turn on = a di/ance equal to ?ree times ! ?ickness ( ! %ank4 #f4 ,lock ) safety wires all turnbuckles & p9s1 & cott]-p9 e nut4 #g4 ,wat* = k9k+ ( wires & _! rubb+ ar\nd controls & :]ev] !y may vibrate aga9/ "o ano!r4 #h4 ,all bolts & p9s mu/ h an easy tapp+ fit only2 d n p\nd !m into position4 ,transcrib]'s ,notes pg #bb ,*ang$3 funi%$ ) dual control to3 furni%$ ) dual control pg #hc ,*ang$3 r ?an fly+ (f 9 a /raight ine to3 r ?an fly+ (f 9 a /raight l9e pg #hf ,*ang$3 to get out ( an imman5t pancake to3 to get out ( an imm95t pancake