cap power for aircraft workbook (1956)

7/30/2019 CAP Power for Aircraft Workbook (1956)

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ffiwPREFACE

The exercises ond octivities prescribed in this workbook will helpyou ottoin the purposes of eoch lesson. These purposes will be broughtfo your ottention by your instructor. No excercise is to be otfempteduntil your reoding ossignment hos been completed. Do not ottempt theexercises until you hove mode preporotion ofter plonning with theinstructor ond poying heed to his presentotion ot fhe first lesson session.Do not hesitote to use every method ot your commond in order to obtoinessentiol informotion. Observe, reod, osk questions of your instructorond fhe resource people thot visit your clossroom. you will note rhotlessons ore numbered in occordonce with o noturol sequence ond not withreference to o porticulor workbook; for exomple, the first lesson of theworkbook: Aircroft in Flight is Lesson Vll; fhot of the workbook:Power for Flight is Lesson XlV. This procedure is olso used to identifyfhe lesson plons of the severol booklets of the rnstructor Guide series.

By meons of o key your instructor will help you correcl Exercisesl, 2, ond 3 of eoch lesson. Since it hos not been possible to key thcresponses to Exercise 4, the quolity of these should be opproised duringdiscussion by students ond instructor.

HAROLD E. MEHRENS, Ediror

P(lWER F(IR AIRCRAFTLesson XIU

EXERCISE NO. I(You hove 5 minufes fo complefe lhis exercise.)Ploce o I in the blonk spoce which precedes o lrue stotement; ploceon F in the,blonk spoce which precedes o folse stotement.

o. .................. Without o dependoble power plont, the oirplone couldnot hove been put into procticol use.b. .....i. . . Before the Wright Brothers mqde their hisioric flight otKitty Howk in 1903, men hod flown in mon corrying gliders.c. .................. From lhe outset, oircroft power plonls hove been relioble

mochines. td. .................. The oircroft engine is o complele power unit ond doesnot depend on reloted syslems lo perform its function.

". . .i.- The principles of the six simple mochines hove no oppli-colion to oircroft power plonts.f. .................. The first tosk of ony engine is to convert potentiol energyinto kinelic -energy.g. .................. Energy, once creoted, connot be chonged inlo onotherkind of energy.h. .................. Procticolly oll oircroft engines ore externol combustion

engines.i.......;....-.... Robert Boyle (1627-l69ll discovered thot the pressureof o confined gos is directly proportionol to its lemperoture.i. .....1......... All internol combustion engines hove pistons lhot turn qcronk shoft by meons of o connecting rod.

EXERCISE NO. 2(You hove l0 minufes fo complefe lhis exercise.)Fill in the blonk spoces with the word, or words, thot properly complelethe stolement.

o. When the pressure of o gos is doubled, iis volume is .i......................,....by one-holf.


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b. The ...c.,....:........:........................., one of the six simple mochines, moybe regorded os on inclined plone wropped oround o shoft.c. One chorocteristic of energy is thot olthough it connot be creoted

nor destroyed, it con be ..............1......d. A mixture of fuel, such os gosoline ond oir, hos

energy.e. Work is defined os force times ....,...1......f, The child's teeter totter on the ployground is on exomple of the. : .. .:, .....,.........g. The wedge is o movoble ...1...,.....................h. ln ....... 1....,...................... lhe then Moior Corl Spooiz ond Coptoin lro

C. Eoker kept thei. lt is lhe ..............;.... .... thot mokes sustoined

flight possible.i. Energy in oction is colled ..........................., energy.

EXERCISE NO. 3(You hove 5 minules lo complele lhis exercise.)Drow o circle oround ihe number preceding the phrose thot mokes lheslolement most correct.

o. lt moy be thot ihe greotest occomplishment of the Wright Brotherswos to design ond build, with the help of Chorles Toylor, the first suc-cessful l. lnternol compustion engine. 3. Aircroft power plont.2. Sooring plone. 4. Commerciol oir field.

b. The cronk shoft of on internol combuslion engine is on odoptotionol

d. The internol combustion engine puts to procticol use the lwoprinciples discovered byl. Orville ond Wilbur Wright2. Generols Eoker ond Spootz3. Robert Boyle ond Jocques Chorles4. Chorles A. Lindberghe. The power generoted by on oircroft reciprocoting engine is pro-

ductive only when hornessed to on oirplone propeller or helicopler rotorbyq l. Control System2. Corburetor 3. Tronsmission System4. Pulley System

EXERCISE NO. 4(Yov hove l5 minules lo complele lhis exercise.)l. Write o porogroph exploining the principles discovered by Robert

Boyle ond Jocques Chorles. How ore these principles put to procticol usein tfrq interngl combustion engine?r' - :ttr ; -'i 2. -Write o porogroph exploining how the potentiol energy in oircroftfuels is converted into the thrust required for powered flight.

Lesson XUEXERCISE NO. I(You hove 5 minufes lo complele lhis exercise.)

Ploce o f in the blonk spoce which precedes o true stotement; ploceon F in the blonk spoce which precedes o folse stotement.L

IfIII

o.b.

,i........ Reciprocoting engines ore olso known os reoction engines.;. . The turbo-iet engine is in mony respects less complicoted

c. The first mon ever to moke o bolloon oscension wosI . The screw.2. fhe wheel ond oxle.l. .f ocques Chorles2. Chorles Toylor

3. The pulley.4.'Ihe piston rod.3. Octove Chonuie4. Orville Wright

thon o reciprocoting engine.c. ....... Most oircrqft reciprocoting engines ore of the "four-

stroke-fi ve-event-cycle" iype.d. .. . .. . lgnition in the combustion chomber tokes ploce some iimeofter the compression stroke is storted ond before the power stroke is

completed.I,t

IA/engine.

The diesel engine shows promise os o future oircroft


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f. .......i..... .... The volves of o two stroke cycle engine open ond closetwice os fost os they do on o four-stroke cycle engine.S. ....,...... Normolly, in-line engines ore liquid-cooled while rodiolengines ore oir-cooled.h. .i Rodiol engines olwoys hove on odd number of cylindersin eoch row,i. . i Jet propulsion is bosed on Newton's second ond third +lows of molion.

li. :t Rocket engines like the turbo-iet engines hove beendeveloped to the point where they con be effectively used in lorge bomberond tronsport type oircroft.EXERCISE NO. 2(You hove l0 minutes lo complefe lhis exercise.)

Fill in the blonk spoces with the word, or words, thot properly completethe stotement.o. The most simple reciprocoling engine consisls of ................,.....

o .............,.......... o ...............:......... ond o ...........,b. Since on oircroft engine must be of comporotively ...,.,;.,.........little use is mode of the diesel os o power plont unit for oircroft.c. The principle odvontoge of iet propulsion of oircroft is .............,..............d. One type of turbo-iet engine hos on where

extro fuel is iniected into the escoping goses, giving oddedto the engine.e. The first iet propelled oircroft thot octuolly flew wos developed

by on ......1...... ............ nomedf. lt oppeors likely lhot reciprocoting engines will be used os the {principol element of ........,............ .... ond lpower plonls for mony yeors to come.g. The .:.-........................ .............. helps convert the stroight-linemolion of ihe piston to lhe rotory motion of the cronkshoft.h. The five events thot hoppen during the four-stroke cycle ore

i. A common opplicotion of iet propulsion is the ..............................................i.,or similor device.i. ...........,.,...................... engines ore eqsier to streomline thon ..11......................r...engines.

EXERCISE NO. 3(You hove 5 minutes fo complele lhis exercise.)Drow o circle oround the number preceding the phrose thot mokes

the stotement most correcl.o. The first turbo-jet power plont wos designed byl. An ltolion nomed Compine2. Chorles Toylor3. Air Commodore Fronk Whittle4. Roberi Boyleb. A iet engine thot hos o device whereby extro fuel con be iniectedinto lhe escoping goses to give odded thrust is soid to be equipped with o

d. Both the intoke ond the exhoust volves in o four-stroke engine oreclosed on lhe 3. lgnition stroke4. Exhoust stroke

l. Hot pipe2. Afterthoughtc. Most oir cooled engines ore of the

I . ln-line type2. Rodiol type

I . lntoke stroke2. Power stroke

I . Turbine2. Compressor

.3. Afterburner4. Afterglow3. Four-stroke-cycle type4. None of these

3. Turbo-superchorger4. None of thesee. Thot port of the turbo-iet engine thqt does the some iob os the] piston in o reciprocoting engine is colled o

EXERCISE NO. 4(You hove l5 minules to complele fhis exercise.)L Show, by meons of o drowing, the position of the volves ond the

direction of trovel of the piston during eoch of the four strokes of oninternol combustion engine.2. Rodiol engines ore usuolly eosier to mointoin thon in-line engines.Why is this the cose?


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lesson XUIEXERCISE NO. I(You have 5 minufes fo complefe lhis exercise.J

Ploce o r in the blonk spoce which precedes o true srotement; ploce onF in the blonk spoce which precedes o folse stolemenf.o................... ln order to get the proper fuel_oir mixture into onengine's combustion chomber, either o diophrogm-corburetor or on iniec-tion-corburetor must be used lo meler ond otomize the fuel qnd mix thefuel with oir.b. ....j............. A floot type corburetor is not offected by ony unusuolchonge in the oltitude of the oircroft os the diophrogm type corburetor is."1c. ..........i....... When fuel is voporized in the corburetor it con couse qdecreose in oir temperoture of os much os 30o to 40o F.d. ..........,....... The fuel iniection system eliminotes completely the prob-lem of ice formotion, since fuel voporizotion tokes proce ot the intoke

volve where temperotures ore normolly quite high.e................... A superchorger is o port of the induction system.f. ........,......... Superchorgers ore primorily used on oircroft enginesdesigned for low oltitude operotion.g. ................. A, iet engine uses o diophrogm type corburetor so thotit will funclion properly regordless of the oltitude of the oircroft.h. ................. A superchorger is o sort of oir compressor.i. ................. All superchorgers operote on the some principle, i.e.revolving blodes press the oir inlo lhe corburetion system ond conse-quently build up monifold pressure.i. I .. The economizer volve in o corburetor works in coopero-tion with lhe occeleroting purnp.

EXERCISE NO. 2(You hove l0 minules fo complefe lhrs exercise,)Fill in the blonk spoces with the word, or words, thot properly complerethe stotement.

o. A corburetor is used with reciprocoiing type engines rhot do notemploy lhe .................... ........... syslem.

b.c.

The first tosk of o corburetor is to .......i......... .............. fuel.The second tosk of o cqrburetor is to ....,,........... the fuel.

.td. The ... 1....., . .......... . ,..,porticles os it is dischorgede. An engine driven internol

corburetor ond the intoke monifold

l. About twice os much2. About holf os muchI . Venturi2. ldle oir bleed

........,....:-,i..i)..;........ helps breok the fuel into smollfrom the corburetor nozzle.superchorger "locoted between the

is colled on ..,1..,,rr...,,.......f. The .:,.i compresses the oir before itreoches the corburetor.g. .. ... . ....,.. is coused by improper combustion.h. Thefuel-oir mixture entering the monifold for distribution to the cylinders'i. ln .r.....r..........:..................... is incorporoted in the oircroft cor-

buretor to ollow on oircroft engine to run while the throttle is fully closed.i. The function of the .. is to tronsmit oir tothe corburetor ond feed the resulting mixture to the cylinders in theproper omount ond ot the proper pressure ond temperoture.

EXERCISE NO. 3(You hove 5 minules to complele lhis exercise.)Drqw o circle oround the number preceding the phrose which mokeslhe stotement most correct.

o. One of the following is not the proper nomencloture for o typeof oircroft corburetor.l Rom oir type 3. Diophrogm tyPe2. Fuel iniection type 4. Floot typeb. When compored to seo level pressure, otmospheric pressure ot15,000 feet is

c. Which of the following is not o port of the corburetor

3. About 15 times os much4. About the some3. lmpeller4. Dischorge nozzle


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d. ln o turbo-superchorger ihe turbine wheel is driven byl. An ouxiliory motor2. The cronkshoft(:) erftorrt goses from the engine4. Air induction motore. Jet engines use

I . Rom oir type corburetors2. Fuel iniection systems3. Fuel iniection type corburetors4. Diophrogm type corburetorsEXERCISE NO. 4(You hove 15 min'ufes lo complele lhis exercise.)

. l.rI .r list' the similorities ond difierences betw'een o turbo-superchorgerodil o turbo iet engine.2r)[ist the odvonioges of the fuel iniection corburetor over the dio-phrb-fm ond flow type corburetors. Whot is the moin disodvontoge ofthe iniection type corburetor?3. Drow schemoticolly the induction system of o lorge oircroft engine.Show the locotion of such ports of the system os internol superchorger,turbo superchorger, corbureior qnd inlqke monifold.

Lesson XUllEXERCISE NO. I(You hove 5 minules fo complefe fhis exercise.)

Ploce o f in the blonk spoce which precedes o irue stotemeni; ploceon F in the blonk spoce which precedes o folse stotemeni... ....-1..... .. lf o mognetic field is moved ocross o conductor, theeffect is the some os lhot which occurs when ihe conductor is movedthrough the mognetic field.

t'b. . i... .. .. lgnition systems ore of two types: generoior ond mogneto.f'c. .......fl... ... The purpose of o condenser in on ignition system is toreduce the electricity ot the distributor.

ad. ........t......... Direct electric storting is the most widely used of ollstorting systems.

.. ::J-.:.......... An electric motor is o generotor operoting in reverse'f. .......;.......... Aircrqft using mognetos for ignition usuolly use the mog'nelo os o source of electricity to operote other oircroft systems.g. -1.- The ignition system of the iet engine is much less com-plicoted thon thot of ihe reciprocoting engine'h......-i......... A booster coil is used to build up the volioge for the"spork-jump" when the engine is turning ot toke-oft RPM'l. ..- J-. . dn induction (secondoryl coil is used with eoch sporkplug to obtoin voltoge needed for the "spork-iump" when low tension

mognetos ore used.i. ........,......... A condenser does not provide o poth for the trons-mission of on electricol current.

EXERCISE NO. 2(You hove l0 minutes to complele this exercise')Fill in the blonk spoces with the word, or words, thot properly com-plete the stqtement'

o. One type of mogneto, the .l :.....:.. does not"step up" the voltoge of ihe primory circuit.b. Electric storters use on electric motor whose source of electricity

c. When o conductor of electricity is moved. through o mogneticfield o current will flow through the..i-.1'......'..';.:.'...."." ":"""" "" "t'd. The ."Lt,*-L-..........1....:..1,...i.... "......... is o revolving contoct point whichposses over o circle o{ other stotionory contoct points' r

e. An inducrion coil of o mogneto is reolly .JtA-**u:J-.4)::-;.,r:r" v'li:thot steps up ihe voltoge. li

f. lf o primory coil which hos 50 turns of wire produces 24 volts,its secondory coil which hos 500 turns will produce ..,-,1...,.*,.-................. volts.

g. The mogneto is o sPeciol kind of..........',.........r... .. . ..'........ ., whichorrcrhgement.

.............. ond stored in on electric

h. ln inertio storting the cronk turns o " lin turn rototes the cronkshoft through o clutch


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li. A current flowing through o conductor sets up d ..r.;..................oround lhe conductot. :i. ln on oircroft mogneto, mognets ore rotqted belween "pole shoes"

by meons of on occessory shoft geored to the .:..................-....,...........,....

EXERCISE NO. 3(You hove 5 minUfes lo complefe lhis exercise.)Drow o circle oround the number preceding the phrose which mokesthe stotement most correct.

o. The voltoge produced by the overoge oircroft mognelo is

Lesson XUlllEXERCISE NO. I(You hove 5 minufes lo complele lhis exercise.)

Ploce o I in the blonk spoce which precedes o true stotement; ploceon F in ihe blonk spoce which precedes o folse stotement.-1-'o. . .l The principle of operotion of the oircroft engine is bosedupon the foct thot heot energy con be chonged inio mechonicol energy.

I.'.b. .......i,...... The first low of thermodynomics stotes thot olthoughenergy moy chonge its form, no energy is destroyed excepl thot lostthrough friction.r-.. .......1...... ln meosuring units of work, the British Thermol Unit (BTUIis used.^-1--d. .......1.......... Mechonicol efiiciency is the rotio of broke horsepowerto indicoted horsepower.*':...e. .......r.......... ln colculoting the indicoted horsepower of on engine,the horsepower produced vories directly with the length of the stroke.:f. .. ........... . . About 20 "/. ol the heot produced in on oircroft combus-lion chomber is corried owoy by the exhoust.--l.-g. . .. .1.... lf o iet propelled oirplone wos flown in o vocuum itsforword velocity would equol the velocity of ihe iet its engine produced.ah. . . ..j .. Crude petroleum is the source of .modern oviotion fuels.i. .......i........ ln reciprocoting engines, the more ropid the fuel vopor

burns, the greoter power the engine will produce.i-i. . .il .... . The obility of on engine fuel to turn into vopor is colledits froctionol distilloiion index.

EXERCISE NO. 2(You hove 10 minutes to complele lhis exercise.)Fill in the blonk spoces with the word, or words, ihot properly completethe stqtement.

o. The .......... ............ .... ..,....1.............1....,....is on index to the slow-burningquolity of the fuel.

l. 20 volts2. 200 volts

neto ignition system.I . Distributor2. Condenser

d. The ignition system found on mosl.-l . Duol mogneto type2. Single mogneto type

e. One of the following is notignition system"i/*\\,,11 Condenser2. Mogneto

3. 2000 volts_4. t2o,O0o volrs

3. Bottery4. Spork plugmodern oircroft is the3. Single bottery type4. Duol bottery type

used to increose the voltoge in the3. Booster coil4. Distributor

b. The most widely used storling system for oircroft is thel. "Spinning the prop by hond" system2. Electric inertio siorting system3. Direct eleclric storting system4. Hond cronk inertio storting systemc. One of the following is not considered o port of on oircroft mog-

Iu

IIEXERCISE NO. 4(You hove 15 minules fo complele lhis exercise.)

I . Drow schemoiicolly on oircroft ignition system depicting the essenriqlports of the system.2. List the four most commonly used storter systems for modern oircroft.r0 ll


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l

I

1l

II

b. An English physicist nomed ........J-:;'tf demonstrotedmony yeors ogo thot it wos possible to tronsform o certoin qmount ofwork. into the some omount of heot.

c' lf oll the heoi energy in one BTU could be solvoged, it wouldproduce .....:7..1.;..... ....... ft./lbs. of work.

d. About ......5.t/.rr........ of the totol heot produced by the recipro-coting engine is expended becouse of fricfion.e. One pound of gosoline hos o potentiol heot energy content of

.?,:jr.:...i:..;.,)............ BTU.f. lndicoted horsepower minus broke horsepower equols 'horsepower.g. One horsepowgr is equol to -1...,:,.i..i,,....:..." " """'minute.h. The letters m.e.p. in thermodynomics stond for 'tli " '

ft.,/lbs. per

i. The iet engine's rote of fuel consumption is .;:"'::'.il"i''Y"'compored lo q reciprocoting engine'\lr I'-

. wheni. Too ropid burning of fuel vopors in the combustion chomber

couses.;)..:;.\;:,...,...,"1'......,....r't.1......,., or o sudden rise followed by o ropiddecreqse in pressure.

EXERCISE NO. 3(You hove 5 rninufes fo complele lhis exercise')

Drow o circle oround the number preceding the phrose which mokeslhe stotement most correci,o. The fuel-oir mixture in o reciprocoting engine combustion chomberburns qt obout:

l. 2OOo Centigrode :3' 2000o Fohrenheit2. 2OO' Fohrenheit 4' 2000' Centigrodeb. The thermol efficiency of on oircroft reciprocoting engine runsobout:

50"/"2s%l. 100%2. 75y. 3.6t2 r3

c. One pound of thrust of o iet engine will equol two horsepowerwhen the speed of the iet oircroft is: 3. 500 MPH4t 750 MPHr. 250 MPH2.375 MPHd. ln colibroting the indicoted horsepower of o four-stroke-cycleengine we con orrive ot the number of pressure strokes per minule bydividing the RPM of the engine by:

-_1,\ 22.3e. A British Thermol Unit is:

I . The omount of heot necessory to roise I cc of woter I o C.2. The omount of heot necessory to roise I ounce of woter I o F.3.. The omount of heot necessory to roise I pound of woter I o C../; The qmount of heot necessory to roise l,pound of woter I o F.

EXERCISE NO. 4(You hove l5 minules lo complele lhis exercise.)

I . Which engine, the reciprocoting or the jet, hos the leost thermolefficiency. Why?2, An ofterburner on o iet increoses the power output of the engine.Whot effect does the ofterburner hove on the thermol efficiency of the

engine.

Lesson XIXEXERCISE NO. I(You have 5 minules lo complele lhis exercise.)

Ploce o f in the blonk spoce which precedes o true stotementi ploce-on F in the blonk spoce which precedes q folse stotement.o. ....i............. Friction generotes heol.

.-' Ib. ........i......... Petroleum is q member of the hydrocorbon fomily.c. .......;.......... The lower the viscosity of on oil, the greoter the weight

it con support without breoking.d. .......,.......... All crude oils (petroleum) ore ospholt bose.

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1:''e. .....i............ Oil gets its lubricoting obility from the foct thot itsmolecules ore greosier thon the molecules of other substonces exceptpure greose.--if. .......1.......... ln oir cooled engines cowl flops ore used to scoop upthe qir thot is used to cool the engines.

,- "aS. l,; ln liquid cooled engines lhe oil in the lubricotion systemocts os the cooloni in the cooling system.h. ......i:........ Jet engines ore liquid cooled.i. .........,........ Wet sump lubricoting systems ore usuolly found on lorge

engines. .?a"--i. .........i........ One woy to help keep cylinder heod temperotures downis lo use o greoter rotio of fuel io oir in the combustion chomber.

EXERCISE NO. 2(You hove l0 minufes fo comp/efe lhis exercise.)Fill in the blonk spoces with the word, or words, thot properly completelhe slotement.

o. Oil, when ploced between moving ports, tends to form o loyeronly one molecule deep; this is known os o .1.I.;.1,...;....:....r.,......i:.,..,,.....:.1:...i\loyer.

b. An index lo on oil's obility to flow ot certqin temperotures is,, nl ..r.,-. 1"',''","

c. The ........i..;i..,...,'.....................,.........,....... test discovers the temperoture otwhich on oil gives off inflommoble vopor.d. The*Cs,,1'll'.1i....i.ij.,,rr-,.',...t.....1-,r................ forces the oil of on qircroftengine oil system from the sump'through o filter, o rodiotor ond bockinto the storoge tonk.e. The .........,........,.,...r.,..1... ...... ..,.:.......... .. is used to feed the oil through oil

lines to the engine ports.f. Two systems of engine cooling ore used in oircroft engines. They.iore the .....\. t...i.i..1..1 ..:..-i:.....,...,'...:t......,, system ond the ....r.i..1....r.............................. system.g. Heot hos been defined qs the motion of the .....i..l'....r.......r...............,....{."J.of o substonce.h. As o result of compression ond ignition, cylinder heod tempero-

lures of on uncooled oircroft engine could reoch .........f..1..........:......degrees F,14 l5

i. Rodiol engines ore usuolly...,|..t..x.................. cooled.Il. .....:......i;.i.......:.......r...i...::.:.................. ore used to control the omount Of oirthot flows oround on oir cooled oircroft engine.

EXERCISE NO. 3(You hove 5 minutes lo complefe lhis exercise.)Drqw o circle oround the number preceding the phrose which mokeslhe slotement most correct.

o. The best lubricoting oil for oircroft engines is:l. Animol oil 3. Minerol oil2. Vegetoble oil 4. Wesson oilb. one of the iests not used to determine the chorocteristics oflubricoting oil is thel. Viscosity test

2,. 'Octone roting test

3. Distributor4. Mqnifold

3. Flosh point4. Sulphur content testc. lndicote which of the following stotements is folse.l. Friction between two metor ports is ress when the ports in con-tocl ore of different metols.2. Petroleum is o member of the greot hydrocorbon fomily.3. oil of the oil system corries oft o greot omount of excessengine heot.4. ln-line engines ore more difiicurt to streomrine becouse theyore usuolly liquid coored engines ond corry rodiotors ondcoolont pumps not found on rodiol engines,d. The s.A.E. hove estoblished viscosity rotings for lubricoting oils.S.A.E. stonds for

I . Society of Aeronouticol Engineers2. Society of Automotive Engineers3. Sigmc Alpho Epsilon4. Society of Americon Engineerse. The oil system consists of on oil storoge tonk, on oil pump, oillines, o sump ond scovenger pump, on oil filter ond ol. Coolont2. Rodiotor

,


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riII EXERCISE NO. 4

{You hove l5 minufes lo complele lhis exercise.)I . Discuss ihe lhree methods of reducing friction belween moving ports.

Give qn exomple in ihe oircroft engine of how the lhree melhods ore usedin combinotion.2. Moke o schemotic sketch of on oircrofi engine oil syslem showingils vorious componenl ports.

Lesson XXEXERCISE NO. I(You hove 5 minules fo complefe lhis exercise.)

Ploce q f in the blonk spoce which precedes q lrue stotement; ploceon F in the blonk spoce which precedes o folse stotement.o. ....t............ To develop power ond lo convert it into thrust ore themoior purposes of the oircroft power plont. The oircrqft propeller vir-luolly succeeds in combining these lwo iosks into one.b. .. -l:. .. The blode of o propeller is o type of oirfoil iust os theoircroft wing is on oirfoil... ......I......... The principle of propeller oclion is bosed on the fqctlhot o decreose in pressure in ony direclion will couse the qir to produceo force in thot direciion.d. ......[-........ All wood propellers ore fixed-pitch ond oll metol pro-

pel 9rs ore vorioble-pitch propellers./ e. ....1:.......... An odiustoble propeller con be odiusted by the pilot

in flight.f. ........: ...... Reversible pitch propellers ore used to reverse the direc-tion of rototion of ihe propeller.g. ....;.. . . ln flight the propeller tip trovels foster thon the pro-peller hub.f,. .....i........... The electric propeller uses on electric motor lo governpropeller speed.i......f......... Blode pitch is defined os the ongle mode by the chordof the blode element ond the plone in which the propeller rotoies.i. ....-I. ... The fixed pitch propeller is o compromise, its pitch settingis neither the best possible for toke-off nor for cruising.

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EXERCISE NO. 2(You hove l0 minufes fo complefe fhis exercrse.)Fill in the blonk spoces with the word, or words, thot properly completethe stolement.

o. Like the rotor of o helicopter, the propeller, in o sense, is o.t...-.......1...........:.....................r............'

\__ b. ln flight the propeller hos two motions, .r...i.,:..1..:-..........r............... ond

............i...................1....,.........., the poth of this motion is ...n..:r.'..i...i....,..........r.... (shopedlike o corkscrewl.c. One clossificotion of propeller is bosed upon whether ihe pitcht-of the propeller blode is ..U.i],.I...1...:...',,1,."..;.. or ...............,...1................d. There ore two lypes of vorioble-pitch propellers; ..J.-..''.1.:...........:...-,..,...," iiond ;......i..'..;...,..'..i...;l;.1..,.,...1..i, le. Constonl-speed propellers ore of two principol types depending

upon the system controlling their operotion. One type uses o .,,..........,,.......;.....,.system; the other, on ..................... system.

f. Both types of constont-speed propellers use o ..*]..,.......;,,..1.....,..........j.......os lhe core of the outomotic pitch control.\g. Some propellers ore duol rototing, they ore colled ,,,..."...r...:..1...i...;:.:..1;.i,. ^,propellers. ' t

h. Propellers thqt ore so constructed thot the pilot con chonge theblode ongle to creote o bockword thrust ore colled i....i..i*i.:...i...,,....r....................propellers.i. The governor of o hydroulic propeller octivotes o control rod

lhot opens ond closes o ...ur..i....,...;.. ..u....,...- ,-,t. s1.. ond olso operotes on'\ |..".:..i...:.......,..,....i.".,.1.i.:i.':..i...,.... which in turn vories the oil pressure on either sidei- 1rof o .,-...,..t.......1..-,r..r..\............ in the dome section of the propeller ossembly..

ielectric propeller, through the control rod,

switch to o l. ..;.....)..;...:,......i......;....................:...........-........j. The governor of on

opens or closes on electricin the propeller hub.


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EXERCISE NO. 3(You hove 5 minutes fo complefe fhis exercise.)Drow o circle oround the number preceding the phrose which mokesthe stotement most correct,

o. Reduction geors qre used in propeller systems, porticulorly onpropellers with lorge diometers to:l. Reduce weor on the sYstem', 2. Keep propeller tip speed below the speed of sound.3. Help keep the engine cool.4. Feother ihe propeller on "deod" engines.

b. Propellers ore feothered to:l. Help broke the oirplone ond lhereby shorien the londing run.2. Reduce drog ond eliminote windmilling on deod engines.3. Get more engine power for toke-off.4. Utilize less gos during normol cruise operotions.c. One type of vorioble pitch propeller is little better thon o fixed-

pitch one, it is the:I . Electric propeller2. Hydroulic propeller

d. Regordless of the length of o propeller blode the speed of thepropeller tip, in relotion to o section midwoy between the hub ond tip,will trovel:l. At ot rote equol to the mid-section2. At o rote equol to 2 times the rote of the mid-seciion3. At o rote one-holf times the mid-section4. At o rote twice thot of the mid-sectione. There is o certoin similority between ihree of the following fromthe stondpoint of function ond design. which one is the dissimilor one?

I . Aircroft propeller2. Aircroft wing

3. Adiustoble propeller4. Controlloble propeller

3. Helicopter rolor4. Aircroft toil sectionEXERCISE NO. 4(You hove l5 minules fo complefe fhis exercise.)

l. Moke o simple diogrom of the moior ports of o hydroulic propellercontrol system.2. Exploin why o propeller blode is designed in such o woy tholthe comber, chord, ond pitch is difterent for eqch section.

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Lesson XilEXERCISE NO. I(You hove 5 minules fo complele lhis exercise.)

Ploce o f in the blonk spoce which precedes o true stotement; ploceon F in the blonk spoce which precedes o folse stotement.ro. ......i... . Engine designers hove been oble to reduce the humberof engine instruments required for modern oircroft engines under thotrequired by eorlier engines.

b. ....:..I........ The pupose of the engine instruments is to keep thepilot informed of the operoting conditions of his engine.c. ..........i ....... Most oircroft engine pressure gouges ore of the vopor-pressure, thermometer lype.d. .................. The tochometer on engines equipped with fixed pitchpropellers gives on indicotion of the engine power output.e, .......i.......... The vopor-pressure type, temperolure indicotor useso bulb contoining o highly volotile liquid.f. ........:......... Electronic mechonisms ore electric devices which employ

vocuum lubes,g. ......... ...... Jet engine controls ore much more complicqied thonreciprocoting engine conlrols.h. .................. lt is by meons of the mixture control thot o proper rotioof fuel to oir is kept in the induction system.i. .................. All engine control systems operote on the "push-pulllube control" system,i. ....i.......... Where outomotic controls ore used, some method ofmonuol control is olmost olwoys kepi os o sofeguord in the evenl of foilureof lhe outomotic system.

EXERCISE NO. 2(You hove l0 minules lo comp/efe fhis exercise.)Fill in rhe blonk spoces with the word, or words, thot properly completethe stotement.

o. Pressure gouges operote either on the ..ru)n,;.r,.i...;'l'i...'..,.,..,.....:....,r... ",..'i..';-.principle or the ........t....i..*.i.,...:....i.l...,...r.:................. principle.


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b. Temperoture indicotors moy employ the principle of the...i-..;...,..:,.............;......,..........., the .................,.....................t.............., or the vopor-pressuretype thermometer qnd Bourdon tube.

c. On lorge multi-engine oircroft where consideroble distonces sepo-rote the point where o meosurement is to be mode, ond the instrumenlponel where the reoding is token isystems ore in common use.

d. The vopor-pressure type temperoture indicotor uses o -....:.....contoining o highly volotile liquid such os methyl chloride, o .'. .'.... ... ........."..i...tube ond o Bourdon tube.

e. The principles underlying lhe operotion of ouiomotic controls ore... i.. ,. ::. ... -...................:....., or electronic.f. The control ...,.....r. .-1....,-.. is o frqme secured to the floorof the cockpit which supports the control quodronts ond control mechonisms.

g. An outomotic mixture control lever hos four posilions' They oreond

h, ,{ monuolly operoted mixture control hos onypositions.

i. ln terms of operoting method, there ore three clossificotions ofengine controls: the ...'..,..,....... .................r.................., the ....r.......... '........,qnd the qutomotic,

i. ln terms of construction there ore two engine control systems.The .....,r.."..:..i..*:..'r.,.......:*..1...i..... ond the ..............,........ ...I

EXERCISE NO. 3(You hove 5 minufes fo complele lhis exercise.)Drow o circle oround the number preceding the phrose which mokesthe stotement most correct.

o, One of the following is not normolly used os qn oircroft engineinstrument.L Oil pressure gouge

2. Fuel pressure gouge3. Monifold pressure gouge4. Cylinder heod pressure gouge20 21

b. Temperoture gouges for oircroft instruments ore usuolly one ofthree types. Which one of the following is not used to meosure lem-peroture?l. Wheotstone bridge2. Thermocouple3. Vopor-pressure type thermometer ond Bourdon tube4. Aneroidc. One of the most importont controls, the one thot helps the pilotgovern the power output of the engine ond the speed of the oirplone,is the: l. Mixture control2. Throttle 3. Propeller control4. Quodrontd. Which of the following engine instruments would you expect tofind on on in-line engine but not on o rodiol engine?l. Cylinder heod temperoture gouge2. Monifold pressure gouge3, Coolont temperoture gouge4. Corburetor oir temperoture gougee, On the control quodront of oirplones equipped with reciprocotingengines ore usuolly found levers morked "P", "T", ond "M". Theseletters stond forl. Propeller, throttle, ond mogneto2. Propeller, turbo-superchorger, ond mixture3. Power, throttle, ond mogneto4. Propeller, throttle, ond mixture

EXERCISE NO. 4At this point, if you should hove ony questions obout the moteriolcovered in the previous seven closses, bring these to the oltention of theinstructor. This period should be devoted to discussing oll questions whichyou ond other students desire to hove onswered.(,R,f. 1

cap power for aircraft workbook (1956)

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