REPORT No.

WIND-TUNNEL RESEARCH COMPARING

419

LATERAL CONTROL DEVICES,PARTICULkttLY AT HIGH ANGLES OF AWl!ACK

I—ORDINARY AILERONS ON RECTANGULAR WINGS

By FRRD E. WDICE and Cm J. WBNZIXGDE

SUMMARY

l’h-is report ‘is the jirst of a serh in which it ti in-

tended to compare the rehztwe ~“ts of a.?-!ordinary

and some special form of ailerorw and other latem.!control devica in regard to their ejlwt on tied con-

trowity, kted 8hzbi?dy, and airplane performance.

5%3 cornparimns are ba8ed on wimi%unnii te8t dutu,

all tb conhol d%ictx being jlted to mod-d wings king

the 8am8 epan, area, and airfoil 8ecii0n, and being

eubjected to tha same seriee of force and rotuibn W8.

In this particndurreport the results are givenfor ordi-

nary ailerons of three di$erent eim. The medium-eized

ailerons, which with @ wpward and downward dq?ec-

iion are wed a8 a standard for comparison, had a

chord fi6 per cent of the wing chord and a span @ pmcent of the semis-pm of the wing. Of the other twosizes, ona was long and narrow and the otlwr 8hort and

wide. TLs redts are @en for @e d@rent aileron77LOV8?WTltS: one with qtud Up-iZ71d-dOW7Ldejection,

one m“th average and ow wilh tzdrenu di~ereniiu.1 hw-

tion, one with upward dq?edion mdy, and one with the

ailerons arranged to jfoat &h respect to the wing.

The results showed that although the ailerons ofmedium size with either th .sguul up-and-down or the

commonly used di~ereniial motion-s ga.oe very un.sti-

factory control above the etal.1, satisj%dory control w

obtaind with tlu 8h0rt, wide ail.em?w with upward deflec-

tion only, and m clo8ely appro& by tti same

ailerons with dreme diferentiu.1 motion. 17w short,

wide and the medium aiJeroru with upward dejection

only aLso gave powerful yawing monwn& which at all

angl-a of aitack wowld aid the rolling, a.!th.ough with

8??d de$t?dti abOVe the 8t& 8@#d W?OW8e ydq

moments occurred. 17w only ailerons which gave no

aa%erse yawing nwmen.i% at any dq%ction or angle ofattack were tti short, wide owe arraq@ to jloai.

INTRODUC’ITON

GENRRAL

One of the most promising methods of increasingthe safety of airplanes is the provision of adequate.lateral control and lateral stabili~ at the low speedsand high angles of attack. Conventional ailerons as

used at the present time are satisfactory for the usualflight range up to angles of attack just below that formaximum-lift coefficient (the stall), but they are verypoor at the ~angles above the stall. This conditionis one of the greatest dangers in prcaentiay flying,and is often the cause of airplamwfalling out of controland into spins. At the relatively low angles of attackbelow the stall the ilight-path angle in a glide is usuallynot as steep as is desirable for a short approabh to alanding. The tlight path can be made staeper byflying at a higher angle of attack; hence it is dtiableto fly and to have good lateral control and stabilityat the higher angles of attack.

Many devices, such as slots and floating W@-tipailerons, have been devised for improving the lateralcontrol at these high angIes. While most of thesedevices have previously been tested in individualisolated cases, it is not possible to get a good com-parison between them because the individual testswere made under dMerent conditions in severaldifferent wind tunnels or in isolated fight tests, and ,with various degrees of completeness.

& part of a general investigation of safety in flightthe N. A. C. A. has undertaken a series of tests inwhich it is hoped to compare all types of lateralcontrol devices which have been satisfactorily used orwhich show reasonable promise of being effective.It is planned first to test the various types of aileronsand lateral oontrol devices on rectangular wings ofaspect ratio 6. Later the best controls are to betested on wingg of diilerent, shape. Throughout theentire investigation all the devices are being subjectedto the same series of wind-tunnel teats which, it ishoped, include all the factors direotly connected withlateral control and lateral stability that oan be satis-factorily handled in a routine manner in a windtunnel. These tests cover the relative merit of thevarious control devices in regard to lateral controlla-bility, lateral stability, and genmal usefulness. Theyinclude regular 6-component force tests with theailerons, or other control devices, both neutral anddeflected various amounts, rotation tests in whichthe model is rotated about the wind-tunnel axis and

367

...---- -.. ... .. ... . ... .... -’,- ./_Jc-tiA%.-... ‘ , -- .—+...:,=4 —-.=.+s . . . --~ 4. - -+.- — -. .+

358 REPORT NATIONAL ADVISORY COMIWPTEE FOR AERONAUTICS

the rolling moment is measured, and free rotationteats showing the range and rate of autorotation.Because of the large effect of yaw on the stability inroll, the teats are made not only with an angle ofyaw of 0°, but also with one of 20°, which representsthe conditions in a fairly severe sideslip.

Throughout the entire investigation it is intendedin so far as possible to use model wings having a spanof 60 inches, an aspect ratio of 6, and the Clark Yairfoil section. The fit wing has ailerons of mediumdimensions (25 per cent wing chord by 40 per centsemispan) representing the average found from anumber of conventional airplanes and, with theaverage maximum deflection of + 25°, will be taken as

—.— .—

t=a50——Io.w”—

/ - a20-

+

—~~=——K2m”—

,.—

—

—m 250”

4 3“

the National Advisory Committee for Aeronautics.@eference 2.)

PR=ENT PORTION OF INVESTIGATION

This particular report describes the tests on threerectangular model wings with ordinary ailerons ofd.iiferent sizes. Tests of this same generil naturehave been previously made at the Bureau of Stand-*. ~eferen~ 3,4, ~d 6.) They do not, however,include all of the factors included in the presentinvedgation.

In addition to the tit wing with medium-sizedailerons, which will be used as the standard of com-parison, a. second was provided with long, narrowailerons and a third with short, wide ones, both pro-

.—

==+===s”Sfofkns @ ordinafes in mr cenf of chord

sf& 0.00 f..5 250 500 7s 10 15 20 30 40 50 60 70 80 90 8s /00Upper .350 5.45 650 Zw 655 9.60 /0.69 //-36 11-70 /1.40 /052 9.15 Z35 522 2.80 /.49 0.12Lowt?l- 3.50 L83 /.47 a93 a63 0.42 a 15 am 0.00 O.m 0.00 0.00 0.00 0.00 aoo 0.00 0.00

PmmEL-DetdlsOfai.lomnsc mClnrkYwiws

the standard with which all the others wiJl be com-pared. Since it has been found through simple flighttests made for the purpose (reference 1) that aileronsof this size and form will ordinmily give satisfactorylateral control just below the still, till of the otherailerons and control devices will be designed to giveapproximately the same amount of control under thoseconditions.

Because of the large number of factors involved inthis investigation, a clear and complete comparisonof the various devices is difEcult. To facilitate thiscomparison a number of standard criterions will beused throughout the entire investigation. All theteats will.be made in the 7 by 10 foot wind tunnel of

portioned to give ap-proximately the samerolling moments as themedium ailerons, withthe same deflection atangles of attack belowthe stall. The resultsare given for severaldifferent kinds -of aile-ron movement; namely,equal up-anddown de-flection, two differentdifferentialmovements,upward movementonly, and one with theailerons arranged tofloat. Control forceshave been computadfrom the Bureau ofStandards teats (refer-ence 6) and are givenwith thepresent rwmlts.

APPARATUS

Model wings.-Themodel wings were madeof laminated mahoganyand the ordinates wereheld accurate in con-struction to within+0.005 inch of those

mecified. The sizes of the ailerons are shown onl&@re 1. The medium ones are 25 per cent of thewing chord by 40 per cent of the semispan. The long,narrow ones are 15 per cent of the chord by 60per cent of the semispan and the short, wide onesare 40 per cent of the chord by 30 per cent of thesernispan.

The ailerons, w-henallowed to float, were both rigidlymounted on a shaft supported in bearings in the wing.For the floating condition they were constructed so asto balance statically about the hinge axis, by means ofa balsa-wood trailing edge and a brass nose piece.

Wind tun.nel.-The 7 by 10 foot wind tunnel has rmopen jet and a singleclosed return passage. The tpnnel,

ORD~ARY AJLEJRONS ON RDCTANGUIAR ~GS 359

the balances, and auxiliary apparatus are described indetail in referenca 2.

For ordinary force teats the model is mounted on avertiti spindle attached to a rectangular fhne sur-rounding the test section of the air stream. Thebalances are arranged to measure all six componentsof the aerodynamic forces and moments about thetunnel axis directly in coefficient form. For the teats”with floating ailerons an optical sighting device isused to Jneasure the angle 8AE?jat which the aibronsfloat.

For both the free-autorotation and the forced-rota-tion tests the models are mounted on an apparatuswhich replaces the force-twt model support. The ap-paratus consists essentially of a shielded shaft mountedon ball bearings at the center line of the air stream.This shaft is either allowed to rotate freely or is driventhrough reduction gearing by an electric motor. Therolling moment due to rolling is meaaured directlyin coefficient form on the regular @li.ng-momentbalance.

TESTS

All the tests were made at a dynamic pressure of16,37 pounds per square foot, corresponding to an air”speed of SO miles per hour at standard sea-levelatmospheric conditions. The Reynolds ~umber was609,000.

Mleron movements.-Four difTerent aileron move-ments were investigated mth the rigid ailerons. Oneof these was with equal up-anddown deflection, onewith average and one with extreme dif&entid move-ment, and one with upward deflection only. If testedindividually the several dHerent movements wouldhave required rLvery large number of tests. It seemedthat a great many of these could be eliminated bytasting the ailerons individually with up-and-downdeflection separately, and then adding the results toget the combined effect. Although theory indicateathat this is not a rigorcualy accurate procedure, be-oause of the ditlerent wing-load distribution, prelimin-ary tests were made which showed good agreementwithin the accur4cy of the investigation. The finaltests were made with the ailerons deflected equal andopposite amounts, and also with one aileron at a timedeflected first upward and then downward. Themoments for the difi%rential deflections were thencomputed from the results of the tests with one ailerondeflected at a time.

The medium differential arrangement was takenfrom a study of several ‘conventional airplanes, themaximum aileron deflections averaging 35° up’ and15° down. The extreme differential movement wasselected to give as nearly as possible the up-onlymovement which seemed desirable from previous tests.With the assumed maximum deflection for this diiler-ential movement one aileron is 50° up and the otheris 7° down. Table I gives the relative deflections of

149900-33-24 .

the right and left, ailerons throughout the range ofdisplacement with the two diilerential arrangements.These are illustrated in Figure 2, -whichalso shows thewsumed linkage systems used for m~~ control-force computations for all the aileron movements.

4 Equal cp-ond-down ‘I

B, Avemge differential fNafl25”

——— —__ ?5 /

#

,\ ,

~1--i ~

/+ --; , 50”----------

I.._- ~=-=

\‘= j_-~’ ‘\. ‘J/~’ 7“

Cj Extreme differential [No.2) A

\ J/” ‘q/”D, Up-only

FWJFtlZ2.-An0r0n lhkOgO~ madmnm defktiom

TABLE I

ASSUMEDDIJ?FERENTIALA~ERONARRANGE~NTS

l&_~tkd(NIJ.1) lExtnme@I@M(No.z ]

mAMon defk&fm b Mm Aileron dakution .

=7=% ‘“I ‘m

e framamrtfcdfcd(seafig.2.)

~ER%iqg%i$.mn-

,.360 REPORT NATIONAL ADVT.SORY COMMITIIED FOR &ERONAIJTICS

Force tests.—Complete series o! force and momenttests were made on each wing model with the aileronsneutral and with the ailerons deilected variousamounts, both while attached rigidly to the wing andwhile floating with respect to the wing. The ailerondeflections tested in the tied copdition were:

(a) Left aileron deflected downward and rightdeflected upward 0°, 10°, 20°, 30°,40°, 50°.

(b) Left aileron deflected downward 0°, 10°; 20°,30°, 40°; right aileron OO.

(c) R~ht aileron deflected upward 0°, 10°, 20°,30°,40°, 60°, 80°; left aileron OO.

When floating wi* reference to the wing, the totaldeflections of one aileron with respect to the other,left aileron down and right up, were 0°, 20°, 40°, 60°,80°, 100°.

The angl=f-attack rm.ge for the force tests withthe ailerons neutral was from – 10° to + 60°, and withthe ailerons deflected, from 0° to 40°. A completeseriesof teatswas made at both 0° yaw and —20° yaw.In the yawed tests the ailerons were deflected in amanner to oppose the rolling moment due to the yawof the wing.

Rotation tests.-A series of free autorctation testswas made on each wing model with the aileronsneutral,&at in the fixed condition and then floating. Thereduction gearing was disengaged so that the modelcould rotate freely about tho tunnel w&. Startingwell below the stall, the angle of attack was increasedin small steps until the model would just start torotate when given a slight impulse by hand. Thisangle of attack denoted the starting point of auto-rctation. The whole range of autcrctation was thenwwered and the angles of attack and rates of rotationwere noted. These tests were made only at 0° yawbecause the rotational velocities became excessivelyhigh at 20° yaw, with possibilities of damage to thetesting apparatus.

A smies of rctation tests to obtain the coefficient ofthe rolling moment due to rolling was made on each ofthe wings with the ailerons neutral, both locked andfloating. The angle-of-attack range was from 0° to40°, and the teatswere made at both 0° and – 20° yaw.

‘ Rotations in both clockwise (+) and counterclock-wise (—) directions were made at a rate representingthe maximum rolling motion likely to occur in flightin gusty air -whenthe pilot is attempting to hold theairplanelevel. This maximum rate of rolling was foundby special test ilights to be such that the coefficient ofrotation has the value

%2‘b=o.05

where p is the angular velocity in radians per second,b is the span of the wing, and V is the velocity ofadvanca.

Accuracy.-The dynamic pressure was maintainedconstant to -within +0.25 per cent. The angle ofattack was accurate to within + 0.10, and the angleof yaw to + 0.2°. The minimum-drag VfdUCS, whichare the averages of several readings, are thought tobe accurate within + 3 per cent. The lift may berelied upon to within + 1 per cent and the rolling andyawing moment coefficients, in general, to with + 3per cent.

The foregoing accuracy applies to anglea af fittackup to and through the stall and also to angles abovo25°. At some of the angles between 20° and 26°,however, critical flow conditions apparently exist inwhich burbling does not occur with exact symmetryover the wing. This dissymmetry sometimes causestwo or more different values of the rolling and yawingmoments to be obtained. The results are consequentlyrather unreliable for the angles of attack between 20°and 25°. The same turbulent condition probablyexists also in flight at the corresponding, anglea and itcm not be certain there either that the same controlmoments will be obtained repeatedly within the abovorfmge of angle9 of attack.

Oscillation of floating ailerons.-Altliough all theailerons were constructed in such a manner as to havestatic inertia balance about their hinge axes, whenallowed to float they fluctuated or wavered slightly atcertain speeds and deflection settings at certain anglesof attack above the stall. The oscillation was notviolent and in most caws was not steady, apparentlybeing associated with the turbulent air flow over thewings. However, it is a condition which might be un-desirable in flight at certain angles of attack above thestall.

RESULTS

Coefficients,-The force-test results are given in theform of absolute coefficients of lift and drag and ofthe rolling and yawing moments:

CD - drlr~qs

(JZf - rolling momentqbs

c.’=~ awing momentqbS

where 5’ is the total wing area, 6 is the wing span, andq is the dpamic pressure.

The cceflicients as given above are obtained directlyfrom the balance and refer to the wind (or tunnel) axea.In special cases in the discussion where the momentsare used with reference to body axes, the coefficients

ORDINARY A~ONS ON

am not primed. Thus, the symbols for the rolling andyawing moment coefficierh about body axes are ~and On.

The resuhk of the rotation teats are green, also about

the wind axes, in terms of the rotation coefficient $#

and an absoluto coefficient of rolling moment due torolling,

where X is the rolling moment measured while thewing is rolling, and the other factors have the usualsignificance.

Tables.—Tables II and Ill list the coefllcients ofQL,CD,0,’, and C.’ fOT0° and –20° yaw, respectively,obtained from the force tests on the wing with medium-sized ailerons (25 per cent chord by 40 per cent semi-span) having the ailerons both neutral and deflectedand in both the locked and floatimg conditions. Theangles at which the left aileron floated with respectto the wing chord are also tabulated, the negative signdenoting aileron up and the positive s;gn denotingaileron down. Table IV gives the values of CX at

‘b-%~~= 0.05, and values of ~ over the free-rotation range

for the same wing at 0° yaw with the ailerons neutralin both the locked and floating conditions. Table V

lists the values of Oi at ~~= O.O5obtained at – 20”

yaw. Tables VI to IX, inclusive, give the resultscorresponding to the above conditions for the wingwith long, narrow ailerons (15 per cent chord by 60per cent semispan); and Tables X to XIII, inclusive,list the results for the wing with short, wide ailerons(4o per cent chord by 30 per ceht semispan).

Figures.-The test results are also given in the formof curves for the wing with medium-sized aileronsJthese ailerona representing the strmdard of compmisonfor the entire invcatigation. The curves for the otherailerons are not given because the shapes of the corre-sponding curves for the three wings are roughly similarand the essential results are all compared in a table ofcriterions.

Fiiure 3 gives the curves of the lift and drag co-efficients against angle of attack for the wing mothailerons neutral, botl locked and floating, and for both0° and – 20° yaw. llolling and yawing moment co-efficients for the ailerons locked with equal up-cnd-down deflection and 0° yaw are plotted against angleof attack in Figure 4. Figure 5 gives the roll@ andyawing moment coefficients for ailerons locked withthe right aileron neutral and the left, deflected downditIerent amounts at 0° yaw. Similar coefficients withthe left aileron neutral and the right deflected updifferent amounts at 0° yaw are given in Figure 6.Fiires 7,8, and 9 give the rolling and yawing momentcoefficients for the corresponding conditions, but at

REc’rANGIJLAR WINGS 361

– 20° yaw. Rolling and yawing moment coefficientsfor the ailerons floating, right aileron up and left downvarious amounts, are given against angles of attackfor 0° yaw in Figure 10, and for –2Q0 yaw-in Figure 11.

Curve9 of free autorotation, *; against angle of

attack, for the wings with ailerons neutral, both inthe locked and floating conditions, are given for 0°yaw in Figure 12. Coefficient+ of rolling moment due

to rolling at !#J= 0.05 are given in Figure 13 for the

wing with ailerons neutral, both locked and floatingat 0° yaw, and in Figure 14 for —.?OOyaw.

CRITERIONSFOR COMPARINGRELATIVEMERIT OFAILERONS

A number of criterions are used for comparing theeffect of the various ailerons on the general airplaneperformance, on the lateral controllability, and on the

/.40Aberc!n.s;

o neufl-d-bckd o“yaw—

1.23d ? VI- I- I--2O”.

~D + - +- fioatim 0. -4AI- I-1.1 -Z. ”,* I

c.I.m I

IY ‘ 1 I I I/ff. $! I I

,I I I I I i

.80

Q.lsu

it3 . .

.e

FIIYJEE3.—Lift and drag mfklen~ 26 per centchordail- neutral; Wand–m yaw

lateral stability. These are explained below and thevalues are listed in Table XIY for the 15 aileroncombinations tested.

GENBEALPERFORMANCE

To compme the relative merit of the ailerons inrqywd to their effect on airplane performance charac-teristics, three simple criterions are used.

Wmg area required for desired landing speed.—Thetit critarion is the maximum lift coefficient CL~S

362 RFIPORT NATIONAIJ ADVISORY COMMTFE13 FOR AERONAUTICS

“TF+R3Jaf. /00, * 1 0———20”

❑ ------ ---30” —‘‘-\, \ ;—-—g:

y-u \1.----- ----~ $,’!

11.080 1I1

// —. k

h *, w

.060 I

‘1 \\I

-F!b% 1.-!$G i ~

.0408

, , (L h

d.

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Righf aileron O“P--- ---- : Left aileron cbo~n—

+:-——20”

v m \ o --------- .J*. —, A—-— 40’

.@i7. \

‘eQ *6 c;-0~ xl

i--t--+____ I ‘M I “1%. \li\

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-.020

0“ 10- ‘- la” 30” 40°Ci

FIGUREL—RollingeJIdgawing mommt aalklents doeta26r=attiafhron UP and down. Aikom Iockd; W YEW

-.+ I I I I I I I IIw 20” 3“ w

aFXJURE(L-RoIUWZ and yawiumoment cmflldentsdnatnZ5rmcentahord

a5x0nuP. Annronalmkacf Yaw

r I

o“ lo- 20” 30” 4Pa

Bmum 5.—Rolllu and yawing moment ccalidonts due to 26w cantohordoikmn down. AIkmna look@ & yaw

. la — — — — –tfigh+ olleronl~~

/ “x. ,

-.x x1 :— —— Eo”

..-~ ❑ --------- 30° —. \ A—- —40”

. Icw+ —-— 50=

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moo \

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,

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0. 10 20° X7D 4 ,.

ORD~ARY AItJ3RONS

.060-

Right oileron O“Left aileron down

+ 10”

.040 o ——— 20”-. ------— 270”—. t—-—t1- - 40”

--- ---- - N-0. .

‘PI3 ~

ut-. - ‘\\ ~ .gZ,

j.woc>-

> bQ \

is -+ ~ h~,

%.

A.

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1<

q --%.-.. xL -1● ---

-. ~ .u --=.-.020 \ /

.- ~-cw’

0“ /0” 20” 30” 40°a

~OUBE 8.-Rollb.w~d Y8w47 moion tomffldeat sdnotoumcantohordahon down Muons look@ –W yaw

.120Leff aileron downRighf olleron up

s8 A—-— coon

.103.-

i\ ‘,ss

c1---- ----080 %% t

ii\I %

.060’~— - h

h\\

‘It \ %tl-0C.040-0

c

%

“Y .,.0=

-.020

-.040..10” 20” 30- 40”

cl

fiOm3E 11.—- and mnvbk’moment-dents due to 25POICOnt

.Im I I d ILeft olleron O“ ,

I+— 10”

fiighf - up / p I o— —20”❑ _-- —30.-

~—a r--2 ~’-” ‘

A——40”I x——. 60°

.LMtl . ~ / 8 -—-80 .-/ , \

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-, \.0s0 / -- ‘

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~ .040 _ _ - * \ *

\-“u \

1 \ \\\\

.020 !~\ \

t

o

-.(XW

o- lo- Jar 30° ~a

Frame 9.—RcdIJngand yawing ~mnt mOfMantsdnoto2drwcontohordaileronnp. Mm 10@k@–W yaw

— - - —- ,-- II IY , Lefi oijeron & wn

Y \: Right oileron u.Im. /-

-.26*—\

;———40”=A,, n ------_-- 6oea

A—-— 80”*_~ ---

k* \\

x—-— 100“*,.0 ~\\ , x Total difference.060’ f

}. ~1

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chordOIIe.ro-mw ad do-& AJ.lnmmfht!q -W yawFmwm l&—RolIlng and Y&@ momentcmf6cfmta dmto25 par cant

chordalkomnpanddown. Aikomfloat&(Pyaw

364 RDPORT NATIONAIJ ADVISORY COMMWPIID FOR AERONAUTICS

which is used as an indication of the wing area requiredfor the desired hiding speed.

Speed range .—The second is the ratio ~~ which

is an indication of the speed range and which, for a

IAiler~ns floaflngl——

. locked —.4m

\

( /’ \

.200,4X ~

I

I 1

I

& \

2V 0

[ I

-.EWO

\

-.4000° 10” 20. 30” 40-

&Fmwaa 12-Effwt 0[ flmtlng 25 par cant chard fdlm’oason atabh automt&

thL A.aamllsIlmlw w yaw

0!

FIOUUEKL-Efleut of floati 26E (xmt cbrd FdkOIMORIOIlhWmOmOnt

cmlklent due to rdlfu at ?#=fuE AEmmm nankaU W YBW

given minimum speed, shows the suitability of thewing for high speed.

Rate of climb.-The third genend performancecriterion, which is an indication of relative merit inclimbing tlight, is the ratio L/D taken at a value of thelift coefficient CL= 0.70. Ii a series of perfommncacomputations made for airplanes with a number ofdifferent wing loadings and power loadings, and with

both plain and slotted wings, this criterion was foundto be satisfactory throughout the entire range.

LATERALcoNTRo~YRolling miterion.-The rolling-moment coefficient

accompanying maximum aileron deflection could beused as a simple criterion of the lateral controllability,

aFIOU8E14.-I3I7.W of fkatfng 26par cant ohord al.lemruon rOll&moment

OMMant while mIling at ?#duM. Atkom new -ZW yew

.

-.

but it does not include all the factors involved and itis not independent of the air, speed nor the angle ofattack. A criterion is desired which expresses theability to roll an airplane quickly a slight amountwhile attempting a smooth gliding course in gusty air,particuhdy at the angles of attack required for landing.z%& requirement is different from that of good maneu-verability in that maneuverability depends mainly on

●

.‘-- EOcm.NmJLm Wnws 365ORDINARY AIIJEIRONS ON

the rate of roll obtained through large angles, while thecontrollability as used here dependa on the accelerationwith which the rolling is initiated. This accelerationexists throughout a displacement in roll of 5° to 20°,depending on the type of airplane, after which the rateof roll is approximately constant. @teference9 6, 7,and 8.) The acceleration obtained at the start hastherefore more effect on the controllability than hasthe iinal rate of roll.

Considering these points, a criterion of lateral con-trollability has been chosen to represent the tangentialacceleration at the wing tip for a given airplane regard-1sss of the speed of advance. This acceleration isdependent upon the mass moment of inertia of thewhole airplane about its longitudinal, or X axis, aswell as upon the rolling moment due to the ailerons.The mass moment of inertia is, of course, not availablefor use in a general criterion, but it is almost entirelydue to the wing, and if a constant weight per unitareais assumedfor the wing structure, the areamomentof inertia of the wing about the longitudinal axis cmbe used with reasonable accuracy. This method thentakes into account the plan form of the wing.

A rolling criterion 1? C iilling the above requirementsmay be expressed by the formula

R C=*

where Ci is the coefficient of rolling momant due toailerons with respect to the body axis (which axis forthe wing alone is taken as the midapan chord line),and I, is the area moment of inertia about the mid-span chord line.

As an illustration of the effect of plan form, if awing has the estreme amount of taper possible, thetip being a point, the value of L is half that of arectangular wing having the same area and span, and0, need be only ha;f as large to give the same value ofR (7 or the same controllability in roll. The factor12 in the denominator of the above formula is in-serted so that for a rectangular wing the value of

~ becomes unity and the rolling criterion becomes

Sim;lyc,

R C-FL

I?rom another viewpoint $; gives the position of the

lateral center of prwsure in terms of the span; sincefor steady flight the lift is always constant and prac-tically equal to the weight, the above ratio is alwaysproportional to the actual rolling moment, and there-fore to the tangential acceleration of the wing tip,regardless of speed, either above or below the stall.

Values of the lateral controllability criterion aregiven for four representative angles of attack: 0°, 10°,20°, and 30°. The 0° value represents the condition

for high speed. The 10° value represents the highestangle of attack, just below the stall, at which present-day ailerons give satisfactory lateral control on con-ventional airplanw. An angle of attack of 20° is wellabove the stall with the Clark Y airfoil and representsapproximately the worst r~~e in regard to turbulenceand instability. The 30° tingleis included here mainlyfor comparison with later tests on wings and controlsystems which are satisfactory at higher angles ofattack.

A recent survey of a number of conventional air-planes showed that most of them had ailerons withequal up-and-down deflection, and that the averagem&nmm deflection was about 25°. A maximum de-flection of + 25° has therefore been assumed for thedata on ailerons with equal up-and-down deflection inTable XIV. For the othel aileron movements the,mtiurn deflections have been selected to give sub-stantially the same rolling control as the standardailerons at an angle of attack of 10°.

Lateral control with sideslip.-The aileron controlin a sidedip is important because the sideslip itselfcauses a rolling moment which, in all ordinary cases,will overpower the ailerons at very high angles ofattack. The criterion -whichhas been taken to coverthis condition is the maximum angle of attack atwhich the ailerons can balance the rolling momentdue to an angle of sidedip, or yaw, of 20°. Above thisangle of attack this amount of side-slipwill cause theairplane to roll against the ailerons at their assumedm&mnm deflection.

Ya&g moment due to ailerons,-In the ideal casein which the rudder, the elevator, and the aileronsperform their main functions independently andwithout mutual interference, the ailerons should giveonly a rolling moment about the body axis and notendency to yaw or pitch the airplane. The pitchingmoment is ordinarily negligible, but the yawingmoment due to the ailerons is often large and in sucha direction that it tends to make the airplane take ayawing motion against that which would normallyaccompany the roll given by the ailerons in a turn.This yawing motion causes a rolling moment oppos-ing that due to the ajlerons, and in some cases, par-ticularly at high angles of attack just above the stall,this rolling moment due to yawing becomes strongerthan that due to the ailerons, and the airplane rollsin the opposite direction.

If it is unavoidable that the ailerons cause someyawing as well as rolling moment, it is desirable thatit be in such a direction that the secondary rollingef%t aids the ailerons instead of opposing them. Infact, for general flying, it is probably advantageousto have an appreciable yawing moment accompmy-ing the ailercn deflection, if it is in the direction tend-ing to aid the ailerons and make the airplane turn inthe proper direction to avoid sidwlip. A yawingmoment of the opposite sense, however, is always

undesirable at high mgles of attack where it can

366 RIIPORT NATIONAL ADVISORY COMMJZTBH FOR ADRONAU!tTCS

often overpower the rudder and induce a rollingmoment -whichwill make the airplane roll against theailerons themselves, sometimes starting into a spin.

This yawing tendency, if present, can be overcomeonly by the rudder, and the criterion used for it issimply the yawing moment cdicient with respectto the body axes C=. The value of this coeflkienton any particular airplane is approximately propor-tional to the rudder deflection required to overcomeit, regardless of the angle of atkck or the air speed.It is essential that the yawing moments be taken aboutthe body axes, for they are often negative with respectto the wind axes but at the same time positive orfavorable with respect to the body axes, these beingthe only ones upon which the pilot bases his mameuvers.The values of C, given in the table of criterions(Table Xl?l) are with respect to the vertical bodyaxis, taken as perpendicular to the midspan chordline and one-fourth of the chord back tim the leadingedge. They are given a negative sign if the secondmyrolling eflect opposes the rolling moment due to theailerons, and a positive sign if the secondary rollingmoment aids the ailerons. For acrobatic purposes itis de&able that this yawing moment be zero, but forordinary flying it is likely that a positive yawingmoment would be desirable.

The yawing moments do not always increase m theaileron deflection is increased, but sometimes reacha maximum negative value with partial deflection,after which they may become positive befora the as-sumed maximum deflection is reached. For thesecases both the positive value at maximum deflectionand the maximum negative value at partial deflec-tion are given in Table XIV, and if the deflection isother than the maximum it is indicated by letters andfootnotes

LATERALST~

In fight the lateral stability is dependent upon manyfactors, but the present wind-tunnel teats are con.iinedto the tendency L%roll caused directly either by rollingor by sidealip. Ordinmily, wings at anglw of attackbelow the stall when rotated about the longitudinalaxis are subjected to a damping moment tending tostop the roll. At the higher angles of attack beyondthe stall they tend to rotate by tl.mmselveswith theslightest disturbance, this of course being autorotation.

&le of attaok above which autorotation is self-starting.-The criterion that is used to compare thevarious ranges of autorotation is the angle of attackbelow which the wing is stable with respect to rollingin that it will not start to roll by itself. Below thisangle of attack the lateral stabili@ is satisfactory, butabove it the wing is unstable in roll, which is anunsatisfactory flight condition.

Stability against rolling caused by gusts.-If givena rotational motion to start with, the wing models willsometimes continue to auwrotate at angles of attack

slightly lower than those at which they will start bythemselves. As stated previously, ~ht tests haveshown that under extremely gusty air conditions, eventhough an airplane is held as level as possible, it is

likely to roll to the extent that ~~=0.05. This has

been taken as the worst case likely to be encountered;in the present igvhgation, tests have been made inwhich the wings have been forced to rotate at such a

p’b “rate that ~V= 0.05, and the rolling moments due to

rolling have been measured. Asecond and more severelateral stability criterion obtained from these tests hasbeen taken as the angle of attack below which therolling moment tends to damp out the rolling.~ This critical angle below which the wing is stable isalso used as a criterion for the condition of 20” yaw and

The above-mentioned angles show the critical rangebelow which the stability is such that any rolling isdamped out and above which the range of instabilitymay be large or small, and the instability weak orintense. In order to show the degree of this insta-bility, the mtium unstable rolling moment whilerolling, Oil which occurs at any angle of attack and ineither direction of rotation is given as a criterion for

‘b

%both 0° and 20° yaw, at z =0.05. The m&nmm

values of CAoccur at angles of attack just above thestall and are greatly influenced by very slight imper-fections. in the form of the models, They shouldtherefore be taken as indications only, rather than asabsolute values.

CONTROLFOFtCEBEQUIRZD

A coefficient representing the force required on thecontrol stick has been computed from the results ofprevious tests on hinge moments (reference 5) madewith ailerons of difFerent aims on a Clark Y modelwing. On account of the fact that various type9 oflinkage are required for the different differential ‘aileron movements, the hinge moments could not beused directly to indicate the relative vahms of thecontrol force required, and it was necessary to assumecertain control linkages. The linkages chosen areshown in Figure 2. The control force criterion is thengiven by the equation

I’xl*~=qxcxsxoL

where F is the control force required and 1 representsthe length of the control lever. As in the case of therolling criterion, the CLin the denominator gives thevalue9 of the coefficient the proper relation regardless

ORDINARY &UJIIRONS ON RJ!ICTA.NGUIAR ~GS 367

of the angle of attack or air speed, steady flight beingassumed. Valuea of the control force coefficient aregiven for the assumed maximum tieron deflection,the top of the control stick being given the samemaximum travel in all caaea.

DISCUSSIONOF RESULTSGBNBEALPERFORMANCE

Referring to Table XIV, it will be noted that themaximum lift coefficients for a! three wings withlocked ailerons are within 2 per cent of the averagevalue, 1.25. The slight diilerence-sare due to experi-mental errors in the construction and testing of themodels. The minimum drag coefficients with theailerons &ed neutral have the same value throughout,

UL I=, is fJSO essentiallyand so the speed-rmge ratio, —CD tin

the same throughout.With the ailerons allowed to float the lift coefficient

falls off from 6 to 14 per cent, the great drop be~with the short, wide ailerons. With the medium andthe long, narrow ailerons the minimum drag also is

CL mns1sss with the ailerons floating, so that the ratio ~

Dm

is about the same as with the fixed ailerons. With theshort, wide ailerons allowed to float, however, the mini-mum drag is appreciably greater and the speed-rangeratio falls off substantially.

The rate-of-climb criterion is also the same for allthree wings with tied ailerons. It is slightly higherfor the mediur!nand narrow ailerons arranged to float,but is somewhat lower for the wide floating ailerons.

LATERALCOtiRO~

Rolling oriterion.-It has been found from flightexperience with several conventional airplanes thatwith average-sized ailerons having equal up-and-downdeflections the lateral controllability is adequate up toangles of attack just below the stall, but that at thehigher angles of attack it is unsatisfactory. Upon thisbasis the value of the rolling criterion ~ C for the me-dium-sized ailerons of the present tests, with a maxi-mum deflection of + 25° at an angle of attack of 10°,is taken as a basic standard value representing theminimum value of the criterion for satisfactory con-trol. l?or these conditions, 0,=0.079 and B C= 0.076.For the other aileron chords the spana were selectedto give about the same value of R Cat the 10° angle ofattack. As is shown by Table XIV, the short, wideailerons give a value about 3 per cent higher and thelong, narrow ailerons a value about 6 per cent lower,all of these being taken with the smne maximumdeflection, + 25°.

Although the values of Cl are reasonably constantfor the various angles of attack below the stall (fig. 16),the effective rolling control as shown by R C is muchgreater for an angle of attack of 0° (high speed) than

for 10°; that is, ~ is 0.076 at 0°, compared with 0.079at 10°, while R O is 0.204 at 0°, nearly three times itsvalue of 0.075 at 10°. Thus, the actual rolling con-trol is much greater than necessmy at the high speedor 0° angleaf-attack condition.

& stated previously, the angle of attack of 20°represents the condition of maximum instability. Italso happens to be about the highest angle of attackwhich can be maintained in a glide with conventionalpresenbday airplanes having slightly ’more than aver-age longitudinal control. The lateral controllabilityis in every case leas at an angle of attack of 20° thanthe satisfactory values obtained at 10°.

The highest value of R C at an angle of attack of20° was obtained with the short, wide ailerons withupward travel only which have within 3 per ce~t of the .satisfactory value at an angle of attack of 10°. The 20°angle of attack does not happen to be a good represen-tative angle for these particular ailerons, as can be,seenfrom Figure 16, which gives the variation of R O withangle of attack. Between the angles of 20° and 23°the rolling control is in excess of the assumed satis-factory value: Between 10° and 20°, however, itfalls about 15 per cent below, although even this valueis probably satisfactory within the accuracy of ourknowledge of what is required.

The peculiar increase of the values of R U with angleof attack which occurred with the short, wide aileronswith up-only deflection iE evident to a lesser extentwith the diilerential movement9 of the same ailerons.It is also noticeable but of very small magnitude withthe medium-sized ailerons. It is not apparent in thecase of the long, narrow ones.

With the short, wide aileronE, the extreme differ-ential movemaut was the next best at a= 20°, followedby the floating arrangement, differential movementNo. 1, and iimilly by the equal up-anddown move-ment which gave a rolling criterion only 59 per cent ofthe ahmed satisfactory value at an angle of attackof 10°.

The long, narrow ailerons gave the poorest control-lability at an angle of attack of 20°, the values of B Cwith the various movements being around one-thirdof the satisfactory value. The standard, or medium-sized, ailerons gave values in between those of theextreme sizes. The best value was found with theextreme differential movement and was about three-fourths of the satisfactory standard value.

Wk% all the ailerons the equal up-anddown move-ments gave the poorest rolling moments at an angIe

of attack of 20°, and in each case the best momentswere obtained with the extreme differential and np- .only movemauta. & previously stated, at the highangles of attack above the stall, particularly thosebetween 20° and 25°, the air flow over the wings wasvery turbulent, which makes the accuracy of the datasomewhat doubtful.

r

368 RDPORT NATIONAL ADTTSORY

At the 30° angle of attack, which was includedmainly to enable later comparisons with slotted wings,etc., the values of R C were very low for all the ailerons.The higheat, strangely, occurred with the long, narrowailerons having equal up-and-down deflection, al-though these gave the lowest values at an angle ofattack of 20°.

Lateral oontrol with sideslip,-The order of merit ofthe various ailerons with respect to the lrn%ralcontrol-lability at an mgle of attack of 20” and with 20°sideslip is approximately the same as without thesidealip at the same angle of attack. The short, wideailerom with the assumed maximum deflection gave a

rolling moment suf6cient to overcome the rollingmoment due to an angle of yaw of 20° up to an angle of

-200I,,

\

\

.160

\

\

\. la

;\

i# c~~

: \

oc \

w~‘\ - Q---SOfisfoc;ory RC

,040 3

0 10” EW” 30” 40-a

FIGURElL-Reb3ti0n beiwem romn&momantOMfment (-br& am) androllingdtorkm for 25w cantchordailmm 5xd up-anddown W

attack of 25° with upward movement only, 24° withthe ailerons arranged to float, and 22° with the extremedifferential movement. The medium-sized aileronswith upward movement only and the extreme differ-ential arrangement me next in order. Above the stallnone of the ailerons with the equal up-anddown orwith the ordinary differential movements gave anappreciable amount of control against 20° sideslip.Below the stall, all the ailerons have an increasedmargin of excess control moment as the fmgle of attackis reduced.

Yawing moment due to ailerons.-It is interesting tocompare the yawing moments due to ailerons with theaverage vilues which can be obtained with rudders onconventional airpkmes. These rudder valuea rangehorn Cm=0.005 to 0.015, the average value being about

CO~ FOR AJ3RONAUTICS

0.01 for the angles of attack below the stall and 0.007for an angle of attack of 20°. & shown in Table XIV,negative (or undesirable) yawing moments are obtainedwith all three sizes of ailerons with the equal up-and-down deflections, and at the angles of attack just abovethe stall they are greater than can be obtained with theaverage rudder. With the average diilerential move-ment (No. 1) the conditions are somewhat better, but

I

.3mo———— E~ual up-and-downo----------- Lltf ferenti?l No. IA—-— . No. 2~ Up-onlyv——- Floofing

.320 8

1

1.230 ‘

I

.30 I

.*

RC

$

.160

.Ck90

h.040

} ./

0 10” 20° 30- 43°a

mO= 10.-RollM aitakq 40w csntcby 80w mnt btl oIIwrm withvarfon9movomarlts

there are still some rather large undesirable negativeVahlea.

.

The ailerons of all three sizes with extreme differ-ential movementi gave very strong positive ymvingmoments with full deflection, but with partial ailerondeflection at angles of attack above the stall they gavenegative yawing moments about equivalent to those

ORDINARY AILDRONS ON

obtained with an average rudder. The ailerons withup-only movement gave very strong positive yawingmoments below the stall with all three sizes, and alsowell above the stall with the medium and the short,wide ailerons. The greatest yawing moments wereobtained with the short, wide ailerons, and at an angleof attack of 20° these reached values about four timesthat obtained with the average rudder. The aileronswith up-only movement when deflected about 10° hadsmall negative or adveme yawing moments at angles ofattack above the stall, but had positive values withfull aileron deflection. This condition suggmts thepossibility of eliminating the negative yawing momententirely by rigging the ailerons with about 10° upwarddeflection to start with and then giving them upwardmovement only or possibly an extreme differentialarrangement.

. The only aileron condition tested which gave noadverae yawing moments at any angle of attack wasthat with the short, wide ailerons arranged h float.The pos@e yawing moments were small at the lowangles of attack corresponding to high speed andcruisiig flight, but were high above the stall, whorethey should be a great help in obtaining good control.The medium and the long, narrow floating ailerom.hadrelatively small positive and negative yawing momentsat all angka of attack, even above the stall.

LATERALST~

Angle of attack above which autorotation is self-starting.-The angle of attack for initial instabilityin rolling, that is, the angle at which the airfoil willstart to rotate by itself if mounted on a ball-bearingspindle parallel to the air flow, was very nearly thesame for all the ailerons tested. Ii every case, allow-ing the ailerons to float reduced both the rate andrange of autorotation, the effect being greatest withthe wide, short ailerons. The wing with the narrowfloating ailerons was stable up to an angle of attack2° higher than with fked ailerons. The wing with thewidest floating ailerons had only a weak rotationthroughout two small ranges, 19° ta 21° and 28° to 31°.

Stabili~ against rolling caused by gusts.—The angleof attack above which the rolling moment due to

rolling ~ is unstable with a rotation such that #=E 0.06

is a more severe criterion of the lateral stability, andthe values are slightly lower. In each case the rangeof stability was raised slightly by allowing the aileronsto float. This effect was small, however, and it maybe stated with sufficient accuracy that all cases testedwere found b be stable against rolling below the stalland unstable above. With 20° yaw, the angle ofattack at which ~ becomes unstable is 5° to 7° lowerthan with 0° yaw.

The maximum unstable v&e of Cl at ~~- O.O5is

rather high with all the fixed ailerons, the valueadiffering slightly for the different wing models onaccount of small imperfections in form. These

RECWANGUIAR WINGS 369

unstable values were reduced b less than half by .allowing the, medium ailerons to float, and to one-fourth by allowing the short, wide ailerons to float.

p’bAt 20° yaw and ~= 0.05 the maximum’unstable value

of ~ is great ‘k one direction in every case, beingappreciably greater than the value of Cl~ due to theailerons. The maximum unstable valuea of a occurat very high angles of attack, hofiever, and could beovercome up to angles of attack of at least 20° by theshort, wide ailerons with extreme differential move-ment, upward movement only, or arranged to float.With the floating ailerons the unstable value of ~ isreduced approximately to half.

CONTROL FORCE REQUIRED

In general the control force required to deflect theailerons the assumed maximum amount is largeat forthe ailerons having the widest. chord. It is aboutthree @nes as great for the short, wide as for the long,narrow ones, md is nearly twice as great for the short,wide ones as for the medium onca. For any particularsize the control force is greator for the up-only, extremedifferential, and floating arrangements than for theordinary diilerential and equal up-anddown systems,both of wiib.ichhad about the same values.

S~Y OF RESULTS

Comparison of the best iilerons.-The most promis-

ing ailerons are compared with reference to the stand-

ard ones having a chord of 25 per cent and equal

up-and-down deflection. One of the outstanding

featunw of the standard ailerons is that at angles ofattack of 20° to 30° the .valuss of the rolling criterionR C are only 50 per cent or less of the assumed mini-mum satisfactory value which is obtained at an angleof attack of 10°. They have good control against 20°sideslip at low anglea of attack, but this control de-creases as the angle of attack goes up until at an mgle .of 20°, or just as the wing becomes well stalled, theailerons just balance the rolling moment due to yaw.Above this angle of attack the ailerons are overpoweredby 20° yaw. The yawing moment due to the standmdailerons is negative or unfavorable at all anglea ofattack, and for the assumed full deflection at angles ofattack above the stall the yawing moments due to theaileronsare greater than the yawing moment which canbe obtained with the average rudder. Just below thestall the yawing’ momenta are about one-half of thevalue of those obtained with the average rudder. Thelateral stability as shov by the tendency to dampout a rollhig motion is satisfactory at the low angle9of attack, even with sideslip as great as 20°, but abovethe stall the wing is very unstable and tends to roll ata rapid rate. The control force required for the stand-ard aileron may be taken as a satisfactory averagevalue for airplanes of medium size and speed. Thiscontrol force is more than twice as great at high speedas it is near the stall, but completa deflection is notordinarily required at the high-speed condition.

.—— ——.-

370 REPORT NATIONAL ADVISORY CO~ FOR AERONAUTICS

Ailerons of about the standard size are frequentlyused with a differential motion similar to the No. 1movement in this series of twts. ‘With this differen-tial movement the ailerons are somewhat better thanthe standard in regard to controllability at the highangles of attack but are nedy as bad in their unfavor-able yawing momenti. At the low speeds wherecemplete deflection is often necessmy, the controlforce required for the assumed complete deflection isslightly less than that required for the equal up-and-down movement.

If suitable operating mechanism were developed,the best all-around ailerons of those tested for lightand small airplanes are probably the short, wide oneswith upward deflection only. This combination givesexceptionally good contiol at the high angles of attack,the value of B Cat 20° being 97 per cent of the satis-factory value at 10°.. With maximum aileron deflec-tion the yawing moments have strong positive yaksat all angles of attack, the only adverse values beingsmall and occurrig with small aileron deflection.Also, the control against sideslip is the most powerfulof any of the aileron combinations tested, it beingeffective up to an angle of attack of 25° as compsmdwith 20° for the standard ailerons. The forces re-quired on the contiol stick at medium and low speeds

-are slightly more thsm double those for the standard(25 per cent chord) ailerons with equal up-and-downdeflection.

li’or somewhat larger airplanes the short, wide aile-rons with extreme differential motion are probably thebest of those tested. With this arrangement the forcerequired on the control stick at low speeds is about thesame as that with the standard ailerons. The yawing

. moments are mainly favorable, the adverse negativevalues being codi.ned to small aileron deflections andthe rolling control at high angles of attack is relativelygood, the value of R U at 20° being 88 per cent of thevalue at 10°.

For an acrobatic airphme, in which case it is desir-able to have each control independent and thereforeto have zero yawing moment due to the ailerons, themedium or the long, narrow ailerons arranged to floatwould probably meet the requi.mments beat. Con-sidering angles of attack below the stall only, verysmall yawing moments are produced by the long,narrow ailerons with the average differential movement(No. 1).

CONCLUSIONS

1. Ailerons of average size with the commonly useddifferential and equal up-anddown movements gave in-adequate controllability at angles of attack above thestall, the rolling momenti being only one-half to twc-thirds of the assumed minimum satisfactory value.

2. At angles of attack above the stall, rolling mo-ments closely approaching the minimum desirable weregiven only by the short, wide ailerons, either with ex-treme d.iiTerentialmovement or with upward movementonly. .

3. The only arrangement with which no adveraeyawing moments were obtained was with the short,wide ailerons arranged to float. These gave ratherlarge favorable yawing moments at the high angles ofattack and very small ones at the low angles of attack.

4. The ailero~ giving the smallest positive or nega-tive yawing moments at all angle-sof attack were, in theorder named, (1) the medium-sized floating ailerons,(2) the long, narrow floating ailerons, and (3) themedium&md ailerons with the average differentialmovement. These latter medium-sized ailerons withthe average differential movement, at an angle ofattack of 20°, gave an adverse yawing moment equalto that which can be obtained with an average rudder.

5. Laxge yawing momenta aiding the rolling weregiven with the assumed maximum deflection by theshort, wide and the medium-sized ailerons with up-ward movement only. Small aileron deflections atangles of attack above the stall, however, gave smalladverse yawing moments.

6. The results indicate that the adverse yawingmoments could be entirely eliminated by rigging bothailerons up about 10° for the neutral position and thengiving them m upward movement only or an extremedifferential movement. It is recommended that further&ts with these conditions be made.

7. When floating, the ailerons gave a substantialimprovement in the lateral stability, the effect beinggreater with the short, wide ailerons. “

8. Allowing the ailerons to float reduced the muci-mum lift coefficient but slightly improved the chaimc-tmistics in regard to climbing perforrmmce with allexcept the widest chord ailerons.

LANGLEY MEKIORIAL AERONAUmCm LABORATOIZY,

NATIONU ADVISORY Commmm FOR AERONAUTICIS,

LANGLEY FIELD, VA., Decendwr10,1981. .

REFERENCES

1. Weiok, Fred E.: Prelhninmy Investigation of ModMoatIonsto Conventional Airplanes to Give Nomtalling and Short-Landing Charaotoristica.. T. IL No. 418,N. A. C. A., 1032.

2. Harris, Thomru A.: The 7 by 10 Foot Wind Tunnel ofthe National Advisory Cornmitttm for Aeronautics. T.R. No. 412, N. A. C. A.,’ 1931.

3. Heald, IL H., and Strother, D. H.: Effeot of Variation ofChord and Span of Ailerons on Rolling and Yawing Mc-ments in Level Flight. T. R. No. 298, N. A. C. A., 192S.

4. Heald, R. H., Strother, D. H., and Monish, B. H.: Effeot ofVariation of Chord and Span of Ailerons on Rolling andYawing Moments at Several Angles of Pitoh. T. R. No.343, N. A. C. A., 1930. .

5. Monish, B. H.: Effeot of Variation of Chord and Span ofAileronE on Hinge Moments at Several Angles of Pitoh.T. 11 No. 370, N. ,A. C. A., 1930.

6. Dearborn, C. H., and Kirschbaurn, H. W.: ManeuverabilityInvestigation of an F6C-4 Fightfng Airplane. T. R. No.386, N. A. C. A., 1931.

7. Norton, F. H., and Br&vn, W. G.: Controllability andManeuverability of Airplanes. T. R. No. 153,N, A. C. A.,1922.

8. Lachmann, G.: Praetioal Tests with the “Auto ControlSlot.” Part II. Diseuadon. T. M. No. 594, N. A. C. A.,1930.

AILORONS ON RWXI!ANWJIAR WINGS 371.

ORDINARY

TABLE II

BORCE TESTS. 10 BY 60 IN. CLARK Y WING WITH PLAIN MLERON8 25 PER CENT C BY 40 PER CENT b/2YAWEOO R. N.=609,000 VELOCITY=80 M. P. H.

a –l@ “-P -P @ P I@ w la” 14” 15” w 17” w 2a” w w w w IMIJERONS LO OKXD-NEUTRAL I

H AILEEONDOWN. RIOETAILEEOI?UP Iar’ . . . . . . .._.-O“’.. . . . . . . ..-.a{-. ______cs’......_.--0{ . . ..-.. -----c7mt. . . . ..-... -a’....__ .....0.’.. -.- . . . ..-.;:,. . . . . . . .

. . . . . . . . . . . . . 1........-----.......-------.............--------—.-—-------------------.-—.--------..-..-..————.-------------------........--.-.-.--.—------.---.-..——.---------........................--.-.-—-

0.m-. m

-: %

-: E.100

–. m7.114

–. CwJJ I—---—---—.-..-------.—-—----—---—----..-------....

am–: g

–. 016

–;;

–. 021. K@

-. oal

—---—---—----—-—.—-—-—----—--——----—----

0.ml -------.010 .–-.–

.w .–-.-.-: O& ;-----

-----.025 .–-.-.

.Ua5 —----–. 039 -------

. m .–-.-.

aozE -------.011 -.--–

.05s -.--.––: ~ -:.-..

- ---–: g ;.::–

- --–: O& ~:__

--

0.011–. Ol!a

–: E–:E-;~

..-——----.—---—----—----------—----—----—----

-am–. cm

.03!3 -. —.- -.–-.––. 015 ----- -----

.016 ----- . . . . . . . .-: ~ ;::– ------

.- -------–: g

I -----------I ------------

—-.--—----

-“w 1------1-“m 1------1-“m 1-----1 --m 1------1-“m I -“J” ‘:::: ‘::::

Tam . . . . . . . . . . . . . .

–. mo -—--...—-.—-

–. m . . . . . . . . . . . . .–. Ma ----.–.––.–.011 -.--. –.-.-–

:% 1:1:::::::::

a 014 J---- o.oa5 -––– -0. M7-. (09 ------- -. Cm ------ 0

~ 1--.-1 .024 ..--– .032 .–-.-. –. cm-.013 ----- –. ma ------- -. cm

ii 1==:1-t? == -$i ❑+ %!!’!

I

1am --- --------

–. m -----------.037 —-.--—.

–. cm —-----------.015 _-–. –.–--.

-: O&o;:-------— -----

–: &3 -.-.---.-.--—- —-—---

-: ~ ~:.: ------—-----

–. OM —A:------

ao19I

o -—----.037Xl& p+

.~

I I 1-—

II

[

.—-

.. --—

.—-------..-——..-——.—---------—.-. .—----

----..-.

------—-----------——..-—---------------.--. —..--. —------------—----

at . . . . . .. .. .. .en’..._.._-_cf .. . . .. .. .. .. .c*’. . ..__. _..al... .. ... .. .. ..C’./.. .. .. .. ... ..of . . . . . . .0.’. . .. .. ..g:,__:::::::::

GJ:_______c.’.. -..._ ..-

{

w -------- ._-..– —...-10” .-..-.. -—--- ---!& ------- ------- ----g -------- .—---- ------

------ .— --- .—----w.-”......-..-......—----

0.010–. m

–; ~

–. cm

–; ~

-. m.07s.IxQ

O.cos–. @la

-: g

-.013

–: g

–. an

–:%

.-pa

-: E.Ola–. 307

-: 1%.m-: g

–. Cu7

—.CK -----.. -—.—-—------—---—.-.-...-.----------------

60” . . . . . . . . . . . . ..- ..--..

/

W . . . . . . . . . . . . ..- ..-.-–w -. . . . . . ------- -----@r ------ . . . . . . . -----

.W.J -----:O&6 ----

4—----

.UiJ..; K ------------- .U

I .022 l___l .010 p._.&-.l .Wa 1--1

c&.-. __- . . ..- @ -a 323 -: g4; y!3J CL% :g 0.951 +% M& : :3J L IM L 16s L 10IOD... . .. .. .. .. W --------

1.12J :~ ulJ CL@& 0:5# a4M.071 .113

aAr._....-..- W –3” -5” -a=’ –P -4” -w.917

-MY –lW –Iw –w -% # –W –w -24” -W -39” -4&

AILERONS FLOATINO-NEUTRAL

LEYTAILEBONDOWN. EIGHTAILERONUP

t0(... ..--... lW ------- .-.–.- ----- aoks ----- :~ ------ ----- 0.030 ..-–– 6.a34 -----14 a018 .––.. -0.0100.’.. -------- liy .- . . ..-. —--- ----- –. wa~f---------- ;

—---- ._. ------ —---- -.% l.––- –.cg ---– –.og ----- –. X

. . . . . . . . . . . . . ! . _________o:’.. _.._._.. 2

I .-. ]

I —. -.-.-—---- –:& .--.– -. (

i$-;:-::: bJ _:::-:. ;_ . . ..- :::::. .:i ::::: .& =::. =:::: _:g =:: _:g ::: .:@. . . . . . . . . ..-

] 1

-. CuJ ;---- –. on. . . . . . . . . ..- 3P z.-:.: .:Z: L7Z: -----

--.---.-—— —---

&_._..- 4W . . . . . . .. —----- .-––W ----------- 19” ----- 19” --- .14”

.m ----- . lCQ -------------- . lm .–-... .Cm ---- 8.645. . . . . . . ..- 404 --.-.. —---- ----- –.gq -----– -.014

409 .-.-. -... —-- -------------------- -.$0 ~:.:. –. m —- G-.~8

--- q: .-.-. —-----~ -----

--- 37” ..-–.------ ----- %101 ..--.. ~.ml

----- .- —.- - ●. 031 --- b—.018..-— .. ---- 35” ---- Zr

::

Cl016 --—-------–. w -----------–2W -–– –––

–. me ---- -----●.OM ----------

–% 1::1:1:11.C$ ❑ ::: ~-.-–

—.-.ao ---. --—---

–. all —-----------1P -_-–. –.–-..mfl -–- . . ..–.-.-

-.cm —---------5“ -----------

10Q------------------- l.r —----

um -.-. -.. —---------- .m —----w

.& ‘---–---’——-’–.% ----- -.%

~ 1==1 .% ::::-- C&. . . . . . . . . . . -- —-----

W IL –:014.6 -. ..--. .-.-—--

------ .“—--- .–%5

●. WI—----—---- 1“

.—. ~-----—--- ..m3—- . . . w

~.W2—----.—--- b—.ml----- -14”-—-.—.—. –: ~—. -..

?{:::::::= :---------

‘---------- % 1..-..-1.-a4,- . . . . . . .._ ----1 & l-------l–----l ‘“ 1------1● AUwons flUOh8t0+1° b g onti th@3C4n~OD-% *Anarom Ilnctnab +3” to +4” Iolder tlmw Condltiom.

372 RDPORT NATIONAL ADVISORY COMWXLEIE FOR AERONAUTICS “.

TABLE III

FORCE TESTS 10 BY 60 IN. CLARK .Y WING WITH PLAIN AILERONS 25 PER CENT C BY 40 PER CENT b/2YAW= –20° R. N. =609,000 VELOCITY=80 M. P. H.

c’._.__--.l $ -U& u;: :~ ‘ 0.?s3(?D----------Cv. . ..-— ----- @ . all .m4 .Cas –:Ec.’-.-.-–.-–- w .002 .W2 .W2 .W.2

AILERONS LOOKED-NEUTRAL

UFI AILERONDOWN. EIOIITM?JtEONUP

cv--------- 10+ .–.-.– —–l---- aa34 __l am am ----- a a31 ----- am ----c.’. ---_-– lCP -------- ----–. -–.-– –. m -_._l —.037 –. m —.-–

1

a 024 --.-..- Clw am ----- . . . . . . .

cl’.–-._..-–. w ------- .-–.. - ----- .W3 .--1 .W3–. 011 -.-–– –: &l ~:-_ –:g ~::::. -.011 -: &o . . . . . . . . ..+..

c.’ . . . . . ------ 20’ ------ ------- –.-.– –. m ---.Q!3 -— .Cm -.--.– .017

-m -_z \–:& I –: J&7 __= –: p.g ~1= –:g +; –:N2& __..: -:m& -: O& -------. . . . . . . . . . . . . .

. ..--..hi’. ._._. ___ w ------- –—--- .–-.–c.’--------- w .-.-.–. -..-.-– .-.-.– –. 033 .-.-– –. 023 –: pJ _.-— –. m —— –. ml ---- –.CW _-.-- -.cca -.020 ------ -._...

-. . . . . . . . . . . . . . . . . . . .

c{-------- 4W --.-.--- -—.– --––- .QM ------ .101 . m ------ . m ------ .0a2 --.-.- .IJMc.’-------- @ --.--–. .---— –--— –: pJ ~:: -: ~ -.023 .--.— -.030 –-— -: :; ;:-:: -.ms ..-–.. -. 04s -. ma

--— .011 ------ . . . . . . .

cl’--------- W ------- ------- ––—c.’-------- w –..--. ----- -.-— –. Cm .._-z –. 023 , Jr% .–––

.113 .–—--. . ..- . . . . . . .

---- . lm ------- .030-. ml ------- -. Cm ..:..1

.016 . . . ..- . . . . . . .-. a30 . . . . . . . –. 048 –.020 . . . ..- . . . . . .

Llsm AILEEOXmm mom .uI.EEoHo“

-1I 1- ‘~g’ ‘ ‘ ‘:%’ ‘ ‘>~ ------- ------cl’--------- ;$ .:-.– —.-— —-— a 014__..-l o.o13––..–

g.:------- .-, - ---- ---— ——— -. cm -._._, –.0” .-..... .......—--.—-——— .——

t ,

–: E ::::1 –:% :::::: -:Z -: E.012 ....... ... ....

—.-—.-———-—.-— -. w.cw .._-_] .031-.------–---- .m

-: E ..---- .......———————-.—--- .016———- .—----- ..-— –. 010 ----- –.015 ----------- -.017

------ . . . . . . .

.(U7 .–.-_l-. Ola

.CG.5----------- .a?a–: F4 . . . . . . . . . . . . . .

------ ---— -—. — .018 .032 ------ . . . . . . ... ——-. —.——. ——— –. 014 —-.– –.om -.–––-–— –. m -.020 -.017 ----- . . . . . . .

.---—m l___[___

----— a 012-.—— –. aM-.-. —------ –: Wo.. -.-—.——-. –: E-.. .-—.-. —.. -: E

EIGHTAILERONUP. IJTiMIXEON O“

1.......-------....—..--—..-..—....-—--------------.-. ..— 0.m

------- -. cm.- . . ..-..-. .— -: 1%-....-.—.-.—-:E-------..---- -:%

I 1Icf.-__...._.lG- --------— -–––-4%’.—--.-–.– w .–.––––— –-—cl’________ m -—___.-.-- ______c.’.–.-_._- 2W -.–-–––.— __-.-ci,_________ w’ -.––. ––—- —---c.’_____ m ––—..-.––- .–—-cl’--- ..–-– w ––—. —-- .—-cL’--.-—.- 4W –-—. —-. -.–—.g:,_--l–____ @Y –--.--——- ––—.

-- -._.–– w –.––..–—- --–---cf-.__-.. w. .-.-.. -. —...- ——-c.’--___— w --.-------.-–- --–—

a ora-. m&

.Ml

.W

.05s

.KQ

.cw’

.014

.072

.am

I——- 0.Ol!a ..-. -..--––– a Ols -----——.-

1–.cm ---.---—- –. m .-–—

.--— .03 -.––– —.-– .Oio ------

..-—— –. cm ----------— –. w ------——— .OM –––--.–— .CEa -----—--— –. m .-––.-––.– -.010 ----.—. — .Oaa –—–. -.–— .W9 ------—-. –: ~ –.-..-.––— –. w ---–-——.- -------—--— .lm -----——.— .W4 .–.-— .–– -: ~ ~–..---——. .Ce5 .--.–.-.-.–...-. —— .Cm ------ –.— .W –71

AILERONS FLOATINO-N13UTRAL

a OM–. cm

.040–. 010

–: E

–:%

–: ~

o

.-.....—------------—---.-------.-. -.—..-----.. -.-—--.----.-.—---------.--..-

a 017–. m7

–: E

–: 1%

-: E

–:%

-: E

—.-.. ....-—.-——.............--------------.....-....-—-------..—.—-.-. — I

am . . ..— . . . . . . .-.W4 ------- . . . . . . .

------- . . . . . . .-f% .—... . . . . . . .

.@n ------ . . ... ..-.010 . ..-.. - . . . . . . .

.016 -..-... . . ..-.-: $y ----- . . . . . . .

------ . . . . . . .-: pg ------ . . . . . . .

. . . . . . . . . . . . .-.010 .- . . ..- -..-...

cI____.... w -awl–aonlaloll a2slas761 ausj o.9491af931 Lozi31La531 Lo761La311 Loa410.73sl a7041 ao741ae161ab12&.:zz--- $ _. ~

a’:-.-...-::: w :% . W1 .wl .WL -.W . WIa@.. _______ w –Y –P –5” —P .% .% -w -

1 1 11 1

~ AILERON 00WN. EIOET AILERON UP

Cf -------- lW ____________ am --– a~l ------1----1 w l--–l w42 l--–l w 1------1 w Ic.’. _______ m’ –—–..—--–.–_ –.CO1 --— –.COJ -------aAr– ______ ~~ __-__d,__ g ––— _ -----

II.———

c?’l’---.—––– m ___. -_— --—–

Pc%’---. -—----w ––.–. ---—----

a$:::::=z: 3$ZZ: ::+-1:a’.-. -.-..-—-. w –—. ---- –—--

——————-.—————.————— I

.—-—.CwJ —. —–-.–

–. $ .–-.– ––——— --—

.Ce3 .—-. —––. O&2.–––. –—–

——— —.-Wa ——. –.-..-U14.——-.. —.—..w ------_.––lW -----------

–. mm@

–: g

-Cm–.o#

–: E81°

. mUl

———-. W5——— 4“-— --—-— –: ~-—-. —-—--—. –: U.—. ---. .—-—.-. . –: E—.-— m-—---- .. Km

.—. ~-—--—

—.— -. m-.-—--— .&—---.-–.OI1-.—. — 4“—----—----- –: g-— ..-—-----——. - –: z.. -.-— 3P

●.w.. -.-—.—. w----—

------- -. y. ....... --—------ ---~-.-.—-.-. —-.-. — -:$..-.—--...... b.046

L.@-. . ....----- 2s”-. . . . . . .. W4

-.034--—-—

a 010-._c

●. 016.-. ~

-SIP●.@n

~. ml

.%-. m5;:;

*--: 014

------ .......-. ...- ........ ..... ......-....... -.-...,.-..... .-.-...,....... .-..-.,------ ... ....------ ............- .......------ .......------- .............- ............... ........-..... -------

a .---–--.–– w’ –.––. _____ –—– a(f------ 4r —– -–--- –

1

. ‘k ––—cL’---.-.—–– w -––-– -——- —--- -.m –— –: y

--------- @ ..-.-.– ---- -–— w ——y+------- W —--- ––—. -–.— . m ––— .1

. . ..-. —— w ––— ––— -.-.-– –.m ——au.___-.–- bm –-—. —— ––—

–.o# ~:_: _._-:.: –:@ _______w .––– -- -— ---

1.410------- a’ ~=:-] “u” ~:::::q “w --F ~:::::::

~::::::

. Ailerons fluotnsb +1” to 2S ondex tbew mndfthns. JAilerons flmtoate +3° to +4” nndor tka condlt!ons.

ORDINARY AILERONS ON REC71XNG’ULAR WTNGS 373

TABLE IV

ROTATION TESTS. 10 BY 60 IN. CLARK Y WINCi WITH PLAIN AILERONS 25 PER CENT C BY 40PER CENT b/2

~v’ahasaraforkotatfonYaw.W Valmky.W m. p. h. R. N.-IW,IIM

{(+) Rotation 36-&m 4 O1w

(~)-. g ----- --------

{

CA -.0210 –. Olw(-~o-mtstp.$; --------- -----. . .

-a Oml -aUJ30 am a OEM am am 0.C440am ----- ---- -––- -0. W15 –.–. -— —- -0. m

-.-. —.- (’) .810 .––– .831 .Wo -—.-. .380 awl am (~) –-.––- ------ ----- --- --—. —-. OICJI -. lWo .W&5 . Olla .C4m .Gza . 01s0 .W50 ..-.-. –.–- ––– -. Wlo —--- ---- –— –. W15

—-. -.— (9 .810 -—.-. .m .3s$4 -.-..-- .WJ .376 .?@ (.) .–––– ------ --- ––– ------

AILERONS FLOATINO-NEUTRAL

-- -awls a 0100 .–..--aw --------------- am -------------- -am3

‘tkJ2x$-{g ::-r-::-:.:-!-.:!-!::.:.::----.’219 .223 km .289 ------ ------ am .330 0.0s4 ----- -—. ––––-

(-) Rotatfon

P%

-.0170 –. 0167 -. 01s3 –. Olffi –. mo —.-. -. am .@m ------- .m . ..–. ----- --- –. 0022 ----- ------ ----- -. w(oonnter baMkwka) -- 1

-------- —. . ..- . --------- -------- . . . . . . ..- ------ -. —--- .242 .22s .al ------ --- .?7s ..-.-.–. ----- —--- ---- --------

s Not aolf-atartM.

TABLE V

ROTATION TESTS. 10 IN. BY 60 IN. CLARK Y WING WITH PLAIN AILERONS 25 PER CENT C BY 40 PER CENT b/2,

G k ~= forfti mtatfon at -# -o.c++) *K ‘kti(-) damping rotation

Yaw-–2@ VeloaltyUEIIm. P.h. R. N.-OQ3,O3I

1a w U? 14” 1P m lW ‘m 2P 23” w w ‘i@ w 30’ w w w 4W

AILERONS LOOKED-NEUTRAL

(~&3&n (03mtor-

J-.--. -.— a -a ON a m14

(+’b$h ~ (*- ~aa%z Clolsi Clam ---–- O-m O.ow ----– 0.ma ----- –-– -—-- 0.0742 --.– --– ––. a w

. . . . . . . . . . . . ..-. -. CrzJl –. Uw –.IEW ‘-.04s4 –. oh%3------ –. 00s –. 072s ------ –. H ------ ------ ------ -. oml -–– -—- --- –. @mI

AILERONS FLOATINQ-NEUTRAL

(-J&w (conntEr-

(+&Mk-(mk:- 6 +o’~ +m -aIM36

1

amm a ows .-–– CL0360 aoew ––– 0.0710 ------ ---- ----- 0.Om ---- -.— —. a 0552

. . . . . . . . . . . ..- fh -.0X2 -. am –. owl –. 0=s –. Oiso ––– -. w –. 0796 ------ -- m ---------- -–— -. w~ ---– -–– —-- –. w

.

374

FORCE TESTS.

REPORT NATION&L ADTISORY CO~ FOR ADRONAUTI(X

TABLE VI ,

10 BY 60 IN. CLARK Y WING WITH AJU3RONS 15 PER CENT C BY 60 PER CENT b/20° YAW R N.=609,000 VELOCITY=80 M. P. H.

1 ,1,1 ,,,1 r i I , 1 I I I

EIGHT AILEBON UP. = AILEBON DOWN

,.,(x-.----.-–. I@ -

— ------------ 1-4--+--JQAJO1P –-– -—---- -.0

&___––.--. ~ l–––-l—––-l-–– -g1_—.-..0i7..”

am–.m

-:g

–. 017.~

‘ao19–. 010

-: g

-: g---

, ,4 1 I ‘-”-““-:C& -– –:g ~: –.W5 -:.- .-.cm -.-.-– -. (xi –. 003 -.603

.. ---- - -- .Ox ----- .Ols ..-.-.. .001-.001 -.004

. –.CQ5 -------–.m --– –.010 ._._ -.olo -- ....-.009 -.m -.007

w.Ce.s------- .m’ ..-.-– .033 .––. .025 —.-. –.W2 –.an -.m

_ ..--.— —.-.-..._I~ I.---J--.J— “- –:$ ------.-:m&3-.-----.-:g ..::_ -:g ~: –.C& ~. –:g—-- ---- -. --

IID17__-..–.ols _--.-.ol3 .z-- :014 -.012 –. 015

I

cf -----------cL’---------- I%I::::=!:::ti=a-.ou ,—-!-.(

0.011–.009

-:E

-:E.Gg I

,0.m ...............-:~ ----- ........

...... ........-.016 ...............

-.............-:E ................g; ...............

–:g ....... ......... ..... ........

-: p?J .... .................-.....-

-.013 -.- . . . . . . . . . . .. . . . . . . . . . . . . .

-: % . . . . . . . . . . . . . .

BIOET AILEEO13UP.I.Em!AILERON00

AILERONS FLOATINQ-ITEUTEAL

awl-. m’

-:E.017

-: ~3

–. m

-: %?

-: % 1am ....... .......-. Ml’ ....... ........

-;% :::::::::::::....... ........

-.011 ....... ............... ........

-; g ....... ........

-.m :::1::::::::::.. .... ........

-:% .. .... ........

EIUQ! AILEEON UP. LEIT AILKEOH DOWN

4-441{:~g~8::-:_:--~I_ ;$ III: zl-—-

ag ___ am . aoza .– a 015 —-. am—. .-. -.y — --y ---- -ql —- --g:::{________ W -------— —.. @ z- —

P-Y

.- —— ---- —--- -- ——f%’--------- w .-.—

.04s --– .046 =_. .ma z

-+$ -

.015

&--------- w .–—. z–– –w -— .-.– -—. .076 .Z

--2 z::;- ZZ; :%J IE -:!---------------

c%’------------- w -— .– – –.COJ --– –:$ z: =—. -..

air_. __---.-– W -—-. –: ~

cf--––._ ‘@ -—–- ‘–-13= ..-–

.C9d z= .m =—-

------cl’ -------------

.a?a .–.- .% .––‘@ –-.–– —– 7- –.C# _-. -.ol5 -__–. o# —-- –.o& ----- -; ~

BAA.---—____c{------------

‘g –––– —— —— —-..lu —-. .% :11. .0s4 ——

--—.

cm’_...__-. ----- --- — .074 -.--– .039

w ––.-.. –-– —- –.m .—- –Al? -—-. –.o# —-- –. O&e!_._. –. 01oaf__________ SW _.-_. ____ _ ‘r --2 —--- --- — 1$’

● AIkom fluohmte s“ to=@ under thesamnditiom.

a 014

-9,—.IXQ●.m-LP

J-. m●.aY3-It?

–: ~

.-...--: %.- ...-

. ..... ........

.-- ... .. -. .-. .

.-...-. ........----- ............... ........------ ......... ..... ......... ..... ......... ..... .........-- .... ............... ........

ORDINARY AHJ!IRONS ON REICIU.NGHJL4R WUWS 375

TABLE VH

I?ORCE TESTS. 10 BY 60 IN. CLARK Y WING WITH AILERONS 15 PER CENT c BY 60 PER CENT b/2YAW = –20° R. N.=609,000 VELOCITY=80 M. P. H.

a

I 8A

EIGHT AILKRONUP. LEIT dlLEEONDOWN

cf_____________m ---------------------a 631 ..-.–. a a30l_.__l a E l___.1 a q l_.__] a 014] ao17 I agg I am I ao14 ]________I@ -------- . ----- ------- -. w ------- –. a-

%’:::::::::::::::::: w ------- –––.- –-.-.. .a55 ------- .Cucm’_ . . .._.. .___.. m -------- -------- ------- –. Ims .-..— –. 01cf.- . . . -------------- m . ..-..– -------- ------- .070 .-–... .ffc%’----------------- w . . . . . . . . . . ----- ..-.g;. _.-__ . . . . . . . . . ~ -..-–.. ––.-.- -._-l .= &...l .!

–.014-:O& -.aca

-:: –:~ -:~

–:g –:~ -.m

–:g –.w -:E-.CG3–: E –:E

–.as .–.-.-.--.-.,

I.015 -.-— -------

-. OL9 ----------.aM .----.. -.-.--,

-. am ..-. -----. -.-.,.Ozl -----– .-..---,

–. 024 ------- —...014 ------------

–. a24 ------------

.. ..1–. w

u,. . . . . . . . . . . . . . . . . . .01’. . . . . . . . . . . . . . . ..- %G’------------ @

gf,_.:.l-: -:::::.-

{

Iv ------- -. . . ..–.-..--. a ou ------- ao~ ‘____ aw ------- am ------- aixe aw. . . ..- -.

g’,.-.-- . . . . .

I

–. am ------- –. w ------- –. aQ ------- –. ala ------- –. MB –. ala------ % 1:::::: ::::.::::::: .016 ------- .CEll . . . . . . . .Om ..-.-.. .017 ----- . on .m

m“ -------- .-.-. &-------- –. 035 . . . . ..- –. m .-—-. –. on ------- –. m ..-... - –. Cs)7 –. mw ------- -------- .-..-.. .Om ------- .024 ------- .027 -.----- .I@a ------- . 01sw . . ..-.. - .-..–- ------- –. m . . . . ..- –. 011 -------–.011 ------- –. 010 ------- –. ml –: M!< ------- ––.-.- –...-- .a34 ------- .m -.-–– .am ------- .(C27 .-.__ .018

Ok’.. - . . ..___ . .._.011

,40 _.__: ------- -..-.. -.011 .------ –.015 ------ –. 014 ------- –. (N3 .--_.. –. 01J5–. 016t

arm -.-.--..-.—-–.0).5-------------.C04 -..-– .––..

–.m --------------.034 -------------

-.011 ------------.m ----------

–.015 -------------

am–. 034

-: g

–. 013.016

–. 015

arm–. Ixbs

–: g

–. 011

–:%!

~ .. ..............-of.-. ._-.. ______0’. . . . . . . . . . . . . . . . . . . .qf.-- . . . . . . . . . . . . . . . . .

RIQET AILKRON UP. LBFI?AILERON 0°

if-_ . ...-–.--_. I@ .-..-– .-------------c’

a 019 ....... 0.017-------a 018 .___l a o13 . . ----- a 019“ . . . . . . . . . . . . . . . . . . . Iw . . ..–.- ------- ------- –. CU3------- –. m ------- -. ala ------ –. @J6 . ..-.-. –. m -: E

cl’ . . . . . . . . . . . . . . . .a’ . . . . ---------------

w -------- -------- ------- .W . . . . ..- .m ------. .CB4 ------- .0?8 . .._.- .a?a .0i3!W -------- ––.-.- ------ –. 0)2 ------- -. w ------- –. m ------- –. m . . ----- –. 011 –. 014

al’- . . . . . . . . . . . . . . . . . w . ------- -------- –.--- .0i4 ..-.-.. .OU ------- .016 ------- .@ .--.-.- .Wc*’ . . . . ..__ . . . ..__ w –.-.-.. .-.-.— ------- 0 . . . . . . . -. m ..--._ –. 037 ------- –. m ..-.-.. –. i)ll –: g

4@ –.-..-. .-- . . . . . .-.-.-- .661 . . . . . . . .051 ----- .049 ------- .IMg ------- .049 .m%::::::::::::::::: 40” .-.–.– . . ..–.. ------- .Wt3 .–.-.- –. C05------- –. 5)7 ------- –. m ------ –. 011 –. 014If ------------------- C@ -.-—. - ..–.-.- . . . . . . . ,Wi3 ------- .W ------- .033 ------- .(& ------- .Wac.’-. -. . .._. --------- w -------- --------------- .IXr3 ------. –. ml ------ –. m4 . ..-.. - –. m ------- –. m –:%!of- . . .._-. _..._.. w -------- .-.--. L--- .W7 ------- .ms --.---- .m ----- .W .-.-.-- .@n .070GL’.- . . ..-. -...... -- W -------- .--–.j ----- . Ola ------- .aa ------ 0 --. —-- —.m ------ –. m –. Cm

AILERONS FLOATINQ-NEUTRAL

a ou–. m

-: E

-: i%

-: g

-. m

-: E

am ‘----- .–.-...–.035 1----- ------

.o12 ‘.-.–.- –--–.-. la .__.- -------

.Cr22------- .-.-.—–. 014 -------.-.—–.013 ---–– ..-.-–

–.w ----.–.–.----.Im3 -.--– -.–.-..

–.an ------––.-...W7 -–--.--------

–.W7 ------–.-..-.

am–. W

.014–. oa2

–: E

–: E

–: E

–: E

11cL...-...-.-...-@ -as& ~ p7 Il17J C@& U& Cm& fl~ L 012 :%2 :12J I.. :;: aaw$.-::::::-::::::::::rO.

–:g –:g –.mc.<:..-.-.:----------w’ .&

-.all –.MO –.Ola –:% –:~ –:~ –:g._mll .4UJ .$ ._KJ .Cm

-:g –:%’.Olz

6~,...___ ......._. m -2’ –3” 4“ –v –W –14” –W -W –W

EIOETMLEEON UP. LEST AILEUON DOWN

I@::,-:-:-:-:::::::::::: --:-:: :::--:: :-:: _. W1 -------–.@5IIam ------- CL629..-..-. arm ------- arm ._.-. - a 0K4

!$::::::::::::::: g :::::: 1::::: ::::::11” ----.--

------- –. OM ..-.-.. –. ma-------

.047 ---..– .IJ ------- .-– -----w ------- –e

.037 ---.–. .025-.. .--. -. . . . .. —.- -- -------- ----..-

OAF.--.._ . .. ... ...- m“ ------- -------- ------–. g ;:::- –.m .–---.m -–.-– –. m .---.– –. w

ci’-- . .. ..__-W ------- 1 ------- e .-...-.

-------2JY .-....- --------...–. .Cm ---: .037 -------.( -_.-.- .W -------.&c*’......._-. ----- 3 ,— -------- ------- –. Cm ------- -. c ------- —.012 .--–– –. 010

${::::::::1:::::::::w ..-.-.. 2

ilJ- --.-::: :::: 1::::-------

. mlm ------ 1P

4@ .-––.- ––.-.- ------- –. on------- .071 ------ .0s9

a&------------------ 41y–. 016 ----- –. 014

------ ------ ‘---- ‘1:=:1 ‘“’-----’ ------- ::~ :::: _.$

. . . . . . ... — . -------------- -------

.------

a ou-._c

-: y

.047-. m9

.E-. ~

-: B

a 019 _: &4–._$

–l&.m ..o13

–. y ●-. m

.CEa ..iz-. y&l ~. Cm

P

–: ~ –: g

.am ..026-. g -–. o&4

a 014 .––_!___–. m --_-l _____

*_—4& ~:::: f::-=:

*—.m .. —-------—

-1—13” ----- ------

.—. ~ .-. —-—-----.CU2 .--. -l.-__.–24” .___l___

I

–. m .––.- ------–. ml -----------–16-= .–-–.-.––..m -.–-––.-—.

-.010 -..--– –--.-–

.-. -.. .—.y

.-. ..—M9

E-------–. &4-------. —--- .079-.--— —.017

1:::: -:E

,,,......

w--.._._._.._._!50= ------------------- .(CL’----------------- W -O-. -.-. -.-. -.-. -.-..-–. m .-__-l-.aap&___________ 6@ ......................- Em -+ 4@ l.-.-+ 44”l_.+ *I-+ w

.Q22015

l-----I---”-l -----

376

ROTA!lXON TESTS. 10

REPORT NATIONAL ADVISORY COIJMHTDE FOR AORONAIJTICS

TABLE VIII

BY 60 IN. CLARK Y WING WITH PLAIN AILERONS 15 PER CENT c BY 60 PER CJENT b/2

?&hEs5a.mforfrwrownYaw-o’. Velwity=Sl m. P. h. R. N.-~, @Xl

o Not sdM=t@.

TABLE Q

ROTATION TESTS. 10IN. BY 60 IN. CLARK Y WING WITH PLAIN AILERONS 15PER CENT C BY 60 PER CENT b/2

Yaw-–z@ VelrxiW-=S3 m. p. h. FL N.-OXI, ml

1“ a I w l!P I 14” W m w !W *W w 2& !& !W S2P2P w w 41Y.

I AILERONS LOO~&NEUTIKAL .I

(-) Rotdim (axlntadlx&ise)— cl- -a 0173 O.ma 0.0122 ami7 fLC428-–. am o.a347 .-..awl .....-..-.. O.om ..-..-...... a 0404

(+) ROb~~ (~~)—————— CL .aub .0375 .W .a52s .@57’2 -–- .071s .asm .–. .aw z . . . . .-.. .070s . ..- . . . . . . . . ,053s

—

AILERONS FLOATINQ-NEUTEAL

(-) Rotdon (aumtadc&wim)-- L -o.01a8 -0. ms aJ& ‘&l ~E 4 ‘w -1---- ~~1--- ---- ---- am 1--------1----1 ‘Mo(+) Ro~on (d~)-–-—————————cs- .0246 -m .Ce55

+--II.Oils .051s.-. .0620 .07$3.-.

ml ---- ‘--- ‘-- wl ---- -1-1=,

0RD1NAR% AIXEU30NS ON RW’I’ANWJT.AR WINGS 377

TABLE X

l?OROE TESTS. 10 BY 60 IN. CLARK Y WING WITH PLAIN AILERONS 40 PER CENT C BY 30 PER CENT 2)/2YA~=OO R. N.=609,000 VELOCITY=80 M. P. H.

a 8A -NY -P –s”wlPl@w 14” w lr w Www w @ We&

AILERONS LOOKED-NEUTRALI

RIom AILBEONm. m AILEEOM’IP3WN

Of . . . . . . . . ----------- lW

I

l-l------------ ----- 0.ml ---- 0.~nIv .---... –––.. ––-. -. KQ 1---1 Vd-----kw? ---- a:;!

2;:::::::1::::::::: a-” ---..-.–.-.–. ---- .070

I

.-. -——-..&

c.’----------------- ~ -.-–.–-.––. ----- -.007-—.-.

af -------------- -.-. —----– ------ .a?a-.—-.—.

S&0s’----------------- ––-– —----- ------ -.QJO

—.-—

ot-...—.-—-—--- ---- ---–– -—– _: ~.—---—.------

—--- -. —--- -.—— ——- –; ~.- —.. --- . lW

G--. -..-. -.--. -.-.-.– I w 1-----1------ ‘---- -“w

----------- –. m J

o ---- —_–. m ––- ----

.0&5 .––- ------.017 — —--

---- .——-: ~ —- —-_

-— ——-–. m -–- –-––

.017 -.-– -—--–. m -.–– ——-

ams am–: :lJ –:ho

–. 021 -.017

–: E -: %’

--:: –: ~

–. am –. m

acw–. m

-: ~

-. ml.014

-: ~

-. 02si

.—--.—.u.”I ----- . Q57

.- .-— –. o19

.--—-—- –: E——-..102-— ----—.—. .%.—- –. Ols

/

-.—--—. “.0—-----—- –:=-. —-.-.--—.--- .%-. —.- –. 023——- .m.-. -—— . a26 I

-—-.—.U.*—-. — .&&---.—.-----—--- –:%!--—-——.-:~-—----——–.027%:::====4 & 1-------1-

~ ALEEONDOWN. EIGHTAILERON&

[ =+: :$I-j:$!;j;lj~/:-~0.014 -—-. a 014 --.-– a Cm ----- am

014 z.-. –:%= 1::. -.016 .--. -.011

..- ——--- ------ 7~a 001 0 –.—-—––.m –.W4 -– -––-.MQ –. Ixll ----–.m7 –.011 ——. ____–.Cm -.m -—.-..–—-.010 –.014 _____–. m –. GM --------–. 016 –. Ols _–___

-all

–.ml–. ms–. 011–. 011–. 016–. 016

i

-o. WI-.m–. W4-. cm–. W6–. o13–.011-.016

Hi--. ---. -----–

1c7,’.___.__.--._.uf . . -----------c#____________

--- — -------------c’- . . ..-- . . . . --------

%:::::::::::::::: -b’lilOETAILEBONUP. LEE7AILERON IY

1a ml -—. __..

-: g ~—-__--. —___

–: g ;:._._.—. ___

–. ml ._-_ ..__—..—_

-; g ~=z ~:_

–. 016 ._–__:.m —-...—––

-. ml .–--.-—..016 .–.– -----

-.010 .—––.—-.

am–: g –: ~ –a~–:g –:~ –.an

.014-: O& –. ml -. m

.019 .019–. o12 –. 010 –. 010

–: E -: z –:%

-; g –: ~ –: E.022

.W all .m2

Of--------------------

1lW -------.__._\ ._-_j aIy9 l.__-l afi? 1-

o.’.. -_.__ ._—___ lW -..-— -.–-l ay~ I.-.-l CLOI?I.--q a%

of ---------------- w .-.-.–. . .en’.. _..__ –.--.-- m . ..-.-. -–.-...-––if-------------------- Qq ----- -–-..\.__J :&j l:::--)-:!

::L::\:::\ .~ I::q-:gO&5

G.’

-J................-W —-—.. .—-— —--- .WI ___-:~

4 Iet____________ m –--– ------ ––.. .M8 ---–c.’. _... -------------- w .--–.. ------- ––– . Ola --–- .5M

rrJ -------- ----- –.-– . M --- . m.——.- —— .016 –.-.. . m

i

.070 –.-.. . as3$ :::::::-::::: 1:: .021 –.–. .012g –.-–.––—- --- . ~f .-.–. . (g ‘1

----—.W-—-..——. –: i%-—-.-——–: E-— .072---- . ml—.- .@a-. -.. . .036-. —-. .a37-.-. ——---- :~

.———.-——- .-—.-. —...-. — .-.———.———.————. 1-—-—.(AM-----—.-.. –: E..-.—.—..--:~——-..—---–.ma-.—— .m..-— —.m

----— .$-5---------- . g!

::,--:::: -::::-. u

L

6(- 1-.--.1-a’-------------- wc’-.. -... -.-. -. —.-.-.. e4cf ------------- 8cm’.- . . ..-. -... -------- Ew ------------------- -WI\ ] l------] .~ 1-----, .Ulo ,------, .u~ ___ .M

~ERONS FLOA~Q-NEUTRAL

i

———.[—.-. 0 1-—---- .W3

aM%

----—..

----

c&.-. _____ 1’IY +. ~ -ag ~ :Zg a~ Clg ag l.. L% l.. l.. l-g ●:g aom CL= M& ag a4sB-- . . ..-. -.. .-. -.. — m

–w “–w –lW :lw –l& :l& –Iw :21” –21” –m=’ –21”●. 333

am . . . ..-.. -._. -._..._ CP -r :* -w -& 44” :&m :%

EIOETAILERONUP. - AILERONDOWNI

of -----------Cm’-.______________

N--—-..-—.—..—-.aam——.— ——.—--—-. .60$—---- ----------——.-. ----. —.--—-. ---- —.- –: ~---. ---. — ---- “.---. ---. -.. —.- .091-.-.-.—-.——. —.-. .:”-.-. -—-. --. .-—-----. —.-. .—. —.-—-— . lb—.-.—-—-———- .Cg-—--.-—-.--—---.----.——-.—— .111-.-. —.. -- —.-. —-. .2. -. -— --------------

---- am—----—.W3 .—--–. W -.7– –.m-— -- –w ---- –11” ––-. –13”.- .-— .071 -—-- .M4 ––-. .W

!!? 1-----!–.%9 ----- –. e -—––. OE ---– –-O%—.-—

-—-. am—-. –LC3-— .-.------ .g!

—.WI–31”

–: q

–:@

-: g

–: g

-—.w-lW0.w–._y

●.oil=-.UM

w●.0i6

. —.014w

●. 046.—. 016

.

—.w–31”ax!

:%b.Ou

t—.~–w=.013

–._~

.014-. g~

——.——-—.———--.-— -—_-—-- ——--——-_____—.-.. —-----.——.___.——.-—.—— -——--.———__————————-- -—_——--—__

&------------. . . . . . . . . . . . . ..-. .,----------------

1g::::::::z-::::=:::-.-.-.-...-._.-.-—.5&L_..._.._..-.. -

--- . . . . . . . . ..-. —---. . . . . . . . . . . . . . . . ..-%::::::::1-71:

c’.’. _ . . ..___ ----8A?--------------

l–----l x

~

—-------- –:$--.-.----—---- –:MJ.—--------- –:E

----

1.W6

————.(33———-. —-- . m—---—. 017---- 24”—-— . Im—— –. Clg

i

———.11*—.-—–. $oJ———--- .?—---—.—-— w-’

II.-.-.. ..-.-.-—..-—-.——..

II I 11 II I I I 1 1 I I I I I w l----l----j

eAllerolls lluOiw3te.&l”to+r Dnd@rtJIEse.cwldltlOra bAnmlm fluCtDate+@ tO+4” OJldarthese CmKuthu

1---l w“ I w“

z—— . . .

ADVISORY CO~ FOR KSIRONA’OTTCS378 RIIPORT NATIONAII

TABLE XI

FORCE TESTS. 10 BY 60 IN. CLARK Y WING WITH AILERONS 40 PER CENT C BY 30 PER CENT b/2YAW= –20° R. N.=609,000 VELOCITY=SO M. P. H.

14 AILERONS LOO=>NEUTIML

!I& cl?& 0.017L 014

-. Ma -. 0/s -.044.014 .049 .Ma

(u& U& f~ CM& l.. : ;O& UZJ :;; : ]OJ 1:g 0.917

–. Cm -. m –. 010 –. Cm -. m –. G24 –. am -: g4J –. 0#3 -: ~ -: E.ml .Cm .023 .m .am .m .011 .017 .0?4

C@& cl%

–. 103 -:g.m

CL... --— v -ag -amcD.-----––— w .019cf--------- @ -: C& –:%a’__ -—___ w

1 1I

~ AILKBON UP. LEXI ~N DOWM

IIam . . . . . . . . . . . . . . . . .-.010 ..................m .................

-.017 . . . . . . . . . . . . . . . . ..M6 . . . . . . . . . . . . . . . . .

–:j2J . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .

-.W . . . . . . . . . . . . . . . ..017 . . . . . . . . . . . . . . . . .

-.W3 . . . . . . . . . . . . . . . . .1cf_–.--—cm’.--. ---—------Cf--——-——c&;_______

.----—. —cO’-.–--.-––––––c{----------cL’.--.–-.—----Cf---–----—c8’.-—–––––– m.——0.ml

——. –.ml-------------- –:%—-—.—— -: E-—- .116———. —.—-—- .%--— –.a33

1----CLL ~::.——-..- —- .@& ;.-.–.—.-. —. ----—----- --———--- .:~ .–––-.-—.- ——---- –: yJ ——

-LxL-‘== “-

0.023 0.010–.014 -.017

–: g -; g

-: ~ –. oil

-: g –; g

–. W.o -. M5

0.015–. 016

-: E

-: HJ

–. 0s1

–: E

am-.013

.019–. 029

-: %

-.; ~

-. mI iIv ------ –––.- —-— am ___ ao35KF -—– –––– _—_-m –-–.- –-m21J ;:__ -—- --— .Cbs3.—– .m

-— ——— -— ---–.m —__–. mw –––.. ––.–- — .ml –— .lmw ---- –––– __-.m . –.m‘r -—– .—– ——- .109 —–– .1144$ ~–—– .—–- -–– –:~o __–:y#

--— ——— -—--- —.5)” —.–. ––—- __–. m —..–.019

m AnxEoiDOWN. EIGHT AIIEao?i o?

IIawl . . . . . . . . . . . . . . . . .

-.m . . . . . . . . . . . . . . . . .

-:% :::::::::::::::::0 -. . . . . . . . . . . . . . . .

–.o19 . . . . . . . . . . . . . . . . .-.W . . . . . . . . . . . . . . . . .-.016 . . . . . . . . . . . . . . . . .

a 011 -––

1

arm -a m-:~ ;.-.-..-:~ ~.

----–:gll ~::.. -.Ou –.o13

.Ols –.m-.ml --z –.017 -.017

.a34 -.-–.. .019 –. WI

4 igj----—--—;$ -–—- ––– —-– : m —– J Ia 018 __ am7 —-— a 017 —-–- CL016 0.005 aam a all a ml -- . . . . . . . . . . . . . .-- .-.-— -—. — ———— ——

~f,______ ~ —— -—- —–: g __-:X& ~:: –: g —-–- -m -:& –: ~ –:mJlj’ @Is

.m —-. . .. .. . .. .. .. ..

—— —. .-..m —- –. W5 —–. -: g ~-:::: -:: ~:-:. –:%

.. .. .. .. . .. .. ...-. 0?3 -.031 -.019 -.m . ...............

$f& —– .g5J —l-l-t?-l— —:g ~:+ —:E

.040 .044-.a34

.rm --------.........-:~ -:~ -.013 .................

-----–.m --: –:x –;~

.013 . . . . . . . . .-...——— -. m -. m -.017—-— .CG9 —-—— 0 —--- –:; –: :g -: ~ -; ~ -: $?/

.117 ——; Og ~:–. . ml –: Og –: &9 -.023 -: %

—.—. .119 .~ .MJ-.. -- -- --- -. -

..-073I-AR

Cew

.032 .––– .%!

.016 .— .016

.= —- .103---

7 . . . . . . . . .- . . . . . .‘4 . . . . . . . . . . . . . . . . .9 . . . . . . . . . . . . . . . . .9 . . . . . . . . . . . . . . . . .1. . . . . . . . . . . . . . . . . .

GJ_.-–.---j w ,__--,--–.,__, .Wu ,––, .UaJ ,—-_, .Ulz ,_–-, .“1, ,--., .Wd , -.UJ1 ,-.”11, -.W, ,-.”,2 . . . . . . . . . . . . . . . . .s .-.- . . . . . . . . . . . . .‘“---2c?-----

—--&____ l-l--.--———.———.CE9_—— ————.. —-- .O11

.Cm———.-—— —— _-.—————

AILERONS FLOATING-NEUTBAL

d ,,, ,,, I

BImm AlmEcm UP. LEST AILXNOKDOWN

........ .... ....

.-....-. .........

......-. .........

.... ---- .........

......-. .........

........ .........

........ .........

k::::::::::::::-.........-..-.......................................-----...... ....................................

cf--_---._–cA’.-—–––––––&-----

-— -------Cm’------------

!#Z:;-+:{:—.. -‘%::-111:c.’–—--—%1:-::1:ck’--.–————————aAr__-.-—

1+1W --- -—-.—– aa34 -–— 0.035w .–.—–––– —– S& ~––– –. onw .-.-— —– — ---w -—---- —— .070 —- :Gw –—–..–——-–- o —— –. a?’~ –-–. --—--.—. w -.-.–. lCP

Ice---—- .103ml ——. —.w —---- %1!33------ .144~ -.-.–. –..%

;

.—— am—- –-ly—-.—. -..—.—. -: ~.——------- . m.—.— –.1#1.——--— .140—-—. -.011r-------——- .?2-.—..—. 016-——- 3P

1—-—am -.-–..——.—. m -------—.—- -11” --------- ma ----------- –. o-g -–––—————-——-——.—

0.027–-.0$

.049-. am

.&-.014

.%–. 019

. F2–. ml

43”

&m–.-.

.mo

.ml

-:y

-:g

-:%!42?

6“ .——.CrJ1 -----.013---.–

w ——.lfa .—-$5 —.–

w

ml

--—.———.-—..1’w-—––.—.w..-.–-–.-.-—-‘.I‘w-————.———...1’‘m——.-—.—--.04rP –-– ––-----–- 30- ––-..w --------- —–. .107 ..–—w -–-—.— -—–. .ml —-—w= —–—.—––—— ‘r –—–

d-—---—.-——.——-__-l-:ij~;;————..w-

. 12n–.CQJ I

● Anm’om flustuate*I” b *2? mlder tmmconditions J Afkons flwtnnte +3° to+4” tinder thwo @mdltfom.

ORD~ARY AILERONS ON RECTANGDL4R ‘WfNGS 379

TABLE XII

ROTATION TESTS. 10 BY 60 IN. CLARK Y WING WTTH PLAIN AILERONS 40 PER CENT C BY 30 PER CENT b/2

g$mfrresaroforhoorototfon.

YaIv.fP l%lodty-~ m. P.h. R. N.-~,OlO

a w’ I l?’I 14” I IF 1P w w w 21” w w w i26=l~l=i29=180=~40=

AILEEONS LOO=PNEUTBAL

(+) Rotntfon

{

6 -a am -a 0210 –o. 0143 a 0310 ~.%. a 0144 a m17 afrim

I

:%7 acl&7 ~:: –o. o14s ---- -..-– -––. -.--— acias –a IIIM

(Ctwkwlso)- g ‘-------- ‘-”----- ‘------ ‘------.311 -------- .334 .37s --- 0.374 a4a3 am -—-- --.-–.-,

(:) J::go 3* -. ~

{

-. 0zU3 –. Om –. w ~.=. . w12 . am .Oim .Crm3 .m –. . Olw –. .-–– -.-.– --.-— . .0170 .Cm6

Ckkwlse):. m ‘-------- ‘---”---- -------- ‘---—-- “.X/l -------- .3s4 .?3s .301 --– .374 -- .m .4U3 ..4M .–.–-.- ,--—.

I

AIIzERON8 FLOATINQ-NEUTRAL

,:-%%&@&?H. N?_,:

(ootrnter- Cb .-;_..- . . .. .._. _–.._.. ._._. ______ ..- . . ..– :140

c Not .MLskuting.

~‘Ea-m‘-------‘- ‘m-----‘%m&3 -a m -a fch ---- -a Im43–– .-.– ------ .---— :~

●. ml ––...-. –.- ..–--.. -------- aw .-.-—

.Wo –. f034 ---- –. m ––.–.– ------ .-.-—

-a C046-———

–. OE.o..——

ROTATION TESTS. 10 IN. BY 60 IN. CLARK Y WING WITH PLAIN AILERONS 40 PER CENT c BY 30 PER CENT b/2

ib oOs{[t] &&RimtiCi h @m for forcodmtedon at ~v- .

YaTv–-ZP VelwitPKI m. p. h. E. N.-@XI,m

I~ERONS LOO~NEUTRAL

I

H~%:E’%%2F)-- ~a -aom arm awr34 afmo aotm –.- aom a as47 _.. amm ------- ._. ao724 ______ Qorss. . . . . . . . . ..- –.oim –.msz –. I1391–.0E5 –.W25 ---- –. W63 –. w .–- –.W ----- ---–. 0707 ---——— –. Mm

AILERONS FLOATINO-NRUTRAL

[+1 FfotMoJl k40CkMm)___- Rotation rnnnkmkkwiw)-. ~ -a 0170 –a w -o#m a 0342. a ohm .-.. a am a otIo _-

–. 022s –. lmlz –. m –.m –. os14 ---- –. 5s%3a o140 ----------- aorm –.. –––– a 04cra

.&Ml –– –. Qw ------------ –.WE9 -- ––-—–. 0r3a

—.. . .,. ----

380 ItIiJPOIiT NATIONAII ADVISORY CO~ FOR AERONAUTICS

TABLE XIV

CRITERIONS SHOWING RELATIVE MERIT OF AILERONS

.

PkbI W 16KU y-t chord by CJI ‘*g%%%g%s(J%%%%s pm ~m~ ~1=~ by ~Sf2e)

Subjwt Odt.wfon stand- gg- :n~- stand- Dffftu’- Dti- Stand- DfUer- DfU6r-

ard,Wzp, #s&, %?$, *, .S g q;, g~, J#, ~&ti : ~;, g$i, J$, :g

dawn K dm down down d~ down down do~m Onto

Vy am9aOrr- Afaximnm CL–

I {

L’Z&2 L222 L= LZ22 L 140 L 270 LZ70 L276 L276 L 169 L25S LZ69 LIW L269 1.m

~om-.z iji%?%’clc$A-~— 7~; 7&4 76.4 76.4 ::: ~h : 7Q.4 7’0.4 70.4

16.9 I&9yi ; ~; ~; g:

M. 9~: FL:

16.!3 16.9 I&9

{

-w—-—.. — .Zls .!U3 .?23 .m ;g .204 :%Mmlwmnhol- %

. lf4 . 1%9 .X3 .m .934 .lm .Z@l .awa= Iw-— —— .071 .071 .076

;g.076 .074 .C69 .07a .W .076 .101

U-aP ____ -.. .CEn . Ols .ml :% .a?a .Om :2 .Ml .om Mi ~.074 .Crda-2m ______ .0s4 .027 .Ola .m –: E .017 .025 M .aa –:% .019 .0.25 .am .022 .026

htilm~yl Maximum a. at whfcb lW la” lW W w w w !zl” 22’ lW Iv w 2P %0 fi”Edferons will b91ancoC’f dne to ~ mW.

Icma=fY-.-——.010.––— .-.–. .016 -l:=. –.-.-. .ms

-.m –.Im7 b–:E b-:E -.:rti..016 .~ 0.~

Y;*b m=t ~

-. ~7 b–. ~ .-.~ -..:e. .-=

a-lw_— __ . Ola -—–– ––— .m

~?]~s~ c% a-zJY’____

. Ola .arl —..- .W-.033 ●—.m ●—.W ●—.ml -—— -. W4 ~-. m %g —:=. —----- —.m7 b—:g 9-:%

.W3 .-––– .—.– -—-–-. . . . . . . . . . . . .

-. m .–. COI ~–. ma –. ON b–. m b–. ~ .–. ~------ .—— .Oal ,010

c% i 031 —--— ~.033–. m –. 010 ~-. m b-: g “-. W

●. OM -—.. —---- —.-. —. . ..-

U-m------- .W1 ..-.-.. --------–. m –. ml f–. MQ –. m –. m *-. m b–: %i f+ Cm

.Wa .m*m ~—.m _. o~ d_. ~ ,-. ~ e-. ~ ------

a fcufnftfal instability h w Me l$o w 19” w w E3” w zl” w w 16” 18” lW

afww fnstabflfty at 17 1P 17 IT Iw 17 17 1P 1P a“ 1P 1P 1P 17” 18 ‘

*0.05 Yaw=W.for fnitie.1fmteMlftY at W lW IF w la” u“ U“ 11” n“

?j$-CLft5Yaw=3P.

16° 12 P W 1P 16”

lfy~=y mutable cl. .Om .Ozs .023 .Cds .Cm .Of$ .049 .049 .0+6 .016 .m .02a .ma .Om .Om

Afy~=mm&ust9ble CL .m .m .mi’ an’ .@) .Cm .0z3 .Qn .QJ3 .071 .IB6 .m?s .a36 .a36 ,047

U-w_.-._. .010 ‘.o12 .015 .Ozl .Ola .017 .019 .023 .M1 .@? ~~ .ma .Cml .070 . aloU-l@____ .m .022 .Mr3 .Im .fm .Cw .03s

.0s3 J!!. ._”_’?!’l ._._m_ .CcQ.037 .007 .014 .019

a-2&_-— .IxG .ma-EIP—— — .m :%! 11::. Iz:z- :11: .W7

.13M -------- . . ----- . . ..-..Wa –.-.-.. -.A— --.-.– .011 .W -.- . . . . .-. -... -----

● to r Where tbe marbnmn ymvfng momaut omumwi Mow maxbnmn daffeatfon, tba M&m fndfmte tbe deffwtian of the UP afkron M follows: ●=10”, *-16”, ● ’23dml,& ..~, f=@..

* hChm a mfnbnum valna of U@9 at .-1P and a maximum of CL079at..2P.~ RC?-O.@34 ata-1~ and 0.091 ata-W.