Aerodynamic Characteristics of NACA 23012 and 23021 Airfoils with 20-Percent-chord External-Airfoil Flaps of NACA 23012 Section

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t1vfl ~ A.ERO. & ASTRO. LIBRARY

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NATIONAL ADVISORY COMMITTEE

FOR AERONAUTICS

REPORT No. 573

c ()? y #- Il l', '3

AERODYNAMIC CHARACTERISTICS OF N. A. C. A.

23012 AND 23021 AIRFOILS WITH 20-PERCENT-CHORD

EXTERNAL-AIRFOIL :FLAPS OF N. A. C. A.

23012 SECTION

By ROBERT C. PLATT and IRA H. ABBOTT For sale by tbe SuperintendeDt DC Documents. WBBbln~ton. D. C. • •• ••••••• Prl. e 10 eent.

Subscription priee. $3.00 per year AERONAUTIC SYMBOLS 1. FUNDAMENTAL AND DERIVED UNITS Metric English Symbol Abbrevia- Abbre vi a- Unit Unit tiOD t ion lueter ____ ______________ (or mile) _________ Length _______ m foot ft. (o r mi.)

l second _______________ __ · Time _________ (or hour ) _______ second (or hr.)

t s sec.

Force _______ __ kilogram _ ___ _ weight of 1 pound _____ F weight of 1 kg lb.

horsepower ___________ P ower ______ __ horsepower (metric ) ______________ __ P hp.

miles per hOUL _______ {kilometers per hOUL ___ __ k.p.b. m.p.h.

Speed _____ ____ V feet per secoud ____ ____ meters per second ___ __ -- m.p.s. f.p.s.

2. GENERAL SYMBOLS P, Kinematic viscosity Weight=mg w, p, Density (mass per unit volume) Standard acceleration of gravity = 9.80665 g, 4 2 2 2 Standard density of dry air, 0.12497 kg_m- _s at m/s or 32.1740 ft./sec.

15° C. and 760 mm; or 0.002378 Ib.-ft.-4-sec.

ltV m, Mass=- a Specific weight of "standard" air, 1.2255 kg/m or g 0.07651 lb./cu.ft.

M oment of inertia = mk • (Indicate axis of

I, radius of gyration k by proper subscript.)

Coefficient of viscosity po, 3. AERODYNAMIC SYMBOLS '/,10' Angle of setting of wrngs (relative to thrust Area S, line) Ar ea of wing SID' Angle of stabilizer setting (relative to thrust Gap G, line) h, Span Resultant moment Q, C, Chord n, Resultant angular velocity b Aspect ratio

Vl

S'

p -, Reynolds Number, where l is a linear dimension }J.

Tru e air speed V, (e.g., for a model aiIfoil 3 in. chord, 100 m.p .h. normal pressure at 15° C., the cor-

Dynamic pressure =~p V2

q, responding number is 234,000; or for a model of 10 cm chord, 40 m.p.s. the corresponding

Lift, absolute coefficient OL = :s

L, number is 274,000) Center-of-pressure coefficient (ratio of distance

D, Drag, absolute coefficient OD = ~

of c.p. from leading edge to chord length) Angle of attack

Do , Profile drag, absolute coeffic ient OD, = ~S

Angle of downwash

Induced drag, absolute coefficient OD, = ~S Angle of attack, infinite aspect ratio

Angle of attack, induced Parasite drag, absolute coefficient OD = DS v Angle of attack, absolute (measured from zero· • q lift position) 0,

Cross-wind force, absolute coefficient Oc = q~ Flight-path angle

R, R es ultant force

EPORT 0.573

AERODYNAMIC CHARACTERISTICS OF N. A. C. A.

23012 AND 23021 AIRFOILS WITH 20-PERCENT-CHORD

EXTERNAL-AIRFOIL FLAPS OF N. A. C. A

23012 SECTION

By ROBERT C. PLATT and IRA H. ABBOTT Langley Memorial Aeronautical Laboratory 77 !)': ::6 1

I

NATIONAL ADVISORY COMMITTEE FOR AERONA UTI CS H E ADQ U ART E RS, NAV Y BU ILDI NG , WA H1 NG TON, D, C, LABORATORIE S, LANGLEY F I E LD, VA.

Cr e at ed by ac t 0( Co ngr ess app r oved :\l ar cb 3, 19lii. fo r tbe su p erv ision and dir e ction of t be scient ific st ud y of [hp problems 0( flig h t (r. S. Corle, Till e 50, Sec. 151). It . me mbl'r bip w as i11 cr l'as(>( 1 to 1;) by act app r oved :\I :l r c lt 2, lfl2fl. Th e mem ber ' ar c aPPo ill tl'(l h.\ · the P r es id e nt, an( l se n 'e f1S snch with out compen ' at ion .

('HART ,ES A. LINDBERG H, L L. D ., .To EPH S, AMES, Ph. D. , Chai1'1llal/, ~ew York C ity .

Baltimor e, Md.

IV II . LlAM P.1\{.>\. CC RA C KF.N, Jr ., LL . D., DAVID W. TAYLO R, D. E n g" Vicc ( ' /w irm(l 'll, Wa s hin gton, D . C.

\Va s bin gto n, D. C.

AUGUSTINI '; \V. ROBI NS, Bri gad ie r Gen e l':ll, United Stat A rm Y, (' II .\Hl.I>:S G. AnnoT, Sc. D. , Cb i ef Mat e ri el Divi 'ion, Ai r Co rp s, Wri g ht Fi pl <l , Dayton, Sec retary , mitb so n inn In s tilution.

Obi o, LVM .\ N J, BRIGG , Ph. D., EUGE N" L. VID AL, '. E. , D ir ecto r, National Bur ea u oC SLa ndnrd s.

Dir ecto r of Air Com me r c , D e pa r t m f' nt· of Commercc.

ARTH UR B. COOK, R ear Admira l, Un i ted, ta tl's Na v y, BOWARD P. WAR NER. 1\1. S' ., Cbief, Bur ea u of Ae rona uti cs, avy D e partment.

1\e w Yo rk C ity.

WI LLIS RAY (:REGG, H. A ..

OSOAR W Es:ro vER, Maj or Ge nera l, Un it ed Slall' s Army, Cbief, t:nited Stale::; \\' ea llt!'r HII I'pa ll.

Ch ipf of Ail' CO I 'PS, W a l' D epartment.

HARRY F. G UGGElN HEIM, M. A" ORV I LU~ \VRI OHT, ". D ., Port W fi . hin gto n, Long I s land , N. Y, Daylon, Ohio, SYDNEY M. KRAUH , Capta in , U ni ted Slates Navy, Bur ea u of ACl'Ullautics, Na vy De p:l1'l mpn!".

(;EORr. E \\ ' . T. EWTS. ni1 'N' l r)?' of ACI'(l'IllJutif'n / R p. ('r l1' f'h '- 10 11 F. Yl eTO RY , S c cl 'e lal'Y IIENRY .1 , K l{ b ~ I J), / ': lIflill eer in ('''a/'f/f' , !,all f/ l ey M e mol'ia.l A CI' ())lfIlllicol !,oIlO/ 'o / m'/I, T, (l11gl ey Fie ld , Va, JOHN J. JU E. ,} 'c Owi e ,,/ A .~. qi 8 /a nt ill };' /11'01) e, /' 0I'i 8, 1"1'111/('( ' TECHNI A I, CO MMITTEE S AERODYNAMI CS AIRCRAFT ACCIDENTS POWER PLA NTS F OR A IR C RAFT I NVF.NT IO NS ANn nF. SI GNS AIR CRAF T S TR TURES AND MATF.RIAL S ()u{Jru' iqlfltiftll IIJ ]( ('8(,(/1'r" ' r(, (/8 of Mili/(/?,l/ (/11d Cir il :l rial ·i on J're/ial'alirJ1l Of R esc (l1 'c ll P1 ·0{l1·aUl. ' Allora lion of rrobl elll.~ }'r e l' e ll/irm ot J)1 / llH r a /i n" Con. 'i r/ (,I' ai'i on of / 111 ' ('1l li OI/8 O FF I CF. OF AERONAUT ICAL I TELLTG ENC E LANGLEY MEMORIAL AER O NAUTICAL LABORATORY W AS RINGTON , D. C.

LANGLEY FIELD, VA.

Coll cction c la ss ifi cat ion , co mpilation , Unified co nduct, fo r all ngpncies, of nnd di ssf' minat ion or sc ien t ific and tecb· . cient ifi c re, ('a l"h on t be f undnm e ntal nical in fOl'mat ion on aeronautic.

p r ohl l'ms of flight, n

REPORT No. 573

AE RODYNAMIC CHARA TERISTI CS OF N. A. C. A. 23012 AND 23021 AIRFOILS WITH

20-PERCENT-CHORD EXTERNAL-AIRFOIL FLAPS OF N. A. C. A. 23012 SECTION

Hy ROBERT C. P[ ,A 1"l ' and IRA H . ABBOTT SUM MARY till extending over th full wmg spa n fl a hi O' h-lift device.

Th e Tesults oj an investigation oj till' geneml aero- Good aerodynamic chflracteri tic have been ob-

dynam ic clw!'([ctetistic oj the 1'1. 1. C. .1 1.. 23012 and

tflined with an extel'l1f11 -airfoil fl ap of Cl ark Y section 23021 ailjoi ls, each eguip]Jf(/ with (~ O. 20c ex tel'nal- (refer en e 1), e pecially when 1I ed in connection with ailjoilflap oj N. A. 0. A. 23 01 2 se ction, aTe presented.

a main airfoil of N. A. . A. 23012 ection. Con ider- The test were made in the N . .fl. . A. 7- by 10100t and ation of known cale ef[ t and drag character istic of vClria bl -d ensit?J wind tunnel and covered a mnge oj the lark Y and N. A. . A. 23012 airfoils indi a ted R eynold T umber that incl1Jded value corre pond in g to th at ubstituting t ll e J. A. . A. 23012 section for the lho e JOT landing cond1'tions oj (~ wide 1'Clnge oj ai rplane.

Clflrk Y ection of the flap might improve the peecl- Besidl's a determination oj th vW'iation oj lift nnd drag r ;1J1ge index of the combination. In add ition, the mall eha racteri ·tics with po ition oj the flap Te lat' ive to the main ailjoil, complete aerodynamic c h(~1'act eris t ics of the .x .Flop hinged af c~ ~ 10" • center of its cL1ljoil-jlap combination with a flap hinge axi se l ec ted to

-------- leading-edge

give mall hinge mom ent we re measul'ed in the two tun- ~: .ar c. , _ nel. ome me(~ S Ul'emel1t oj air loads on the flap it e{f _______ -------- .:~ _ c;.. ".,;:>+

c

•• • • j -Flop (a) in the presence oj the wing weTe made in the 7- by lO-joot angle wind tunnel.

la) Su r vcy of fi ap positions.

From the data obtained, the e:r t enwl -(~ iljoil }lap in combi nat i on with an ai ljoil app ear to be one oj the mo t I ~ ______ . c, g nerally at is jactol'Y high-lift device investigated to date.

<----------- ~--- ~.l:Q

The combination te ted offer a l'e latively high va lu e oj A - :'1-.""-" " (b) A' .:. "''.' , >q maximum lift coefficient with low l)rojile dmg in the high- Hmge [-ift mnge. At low lift coefficients it gives ve ty new'ly Cl (Il) B Ala nced hin ge axis.

low value oj pl'ojile dmg as a good pla in ai1joil oj com- / I ris I Axis t . ~ 0.250cr 0.21Ocl parable thickness. i1 ' uctuml and tabi lity pl'oble ms n . 100 <'1 . 100 <1 (L sociated with th laTg e negative pi tching moment oc- A' .03 2c ID .030e It!

n' .054£'. .05~c.

curT'ing at Mgh lift coefficient may be slightly gl'eatel' FI GURE I. . Flnp' Rc llin!!: "etails. The N. A. C. A . 23012 air foil with 0.20c~ j • A.

them in the case oj ol'd in ary and split flaps.

C. A. 23012 externa l·airfoi l fiap.

I TROD TIO cen tor-of-pressure travel of the . A. C. A. 23012 air- on ideration of the external-airfoil It ap as a high- foil indicated the po ibility of hinO'inO' it a a flap in lift clevi e indicates that it may be generally app lie 1 to uch a manner that operating mom nts lower than improve airplane performance. Previou inve tiga- tho e of the Cla rk Y flap might be o bt ained .

A preliminary investigation of the . A. C. A. 23012 Lion of thi d vice ( ee ref rence 1) have hown that ection u eel for both the main airfoil and the flap wa it i capable of developing hiO'h lift coefficient and made in the 7- by 10 -foot wind tunne l to determine th at it give lower drag at the e hi O' h lift coeffici ent Lhan ordinary or plit flap. Thu it may be more the variation of lift and drag characteri tic wi.th favorable to uch item of performance a take - off and position of the fiap relati, e to the main airfoil. A cei lin O'. In addition, it can be balanc d to have Yery hinge-axi location int ended to give low operating low operatinO' moment throughout it range of de f! c- moments and good aerodynamic characteri st ic wa fin and, if large advers yawing moment are accept- th n elected and fmal force tests were made with the a bl e, it may be used to ObtflID lateral co n trol while f1f1P hinged at this po ition and set at var iou angles.

2 REPORT ATIO AI, ADVISORY COMMI'T'TEE FOn AERONAUTIC'S

Th r te s ts in thr 7- by 10-f ooL wi.. ncl tu nnrl wr l' r co n- number of flnp nngks wrl'r inYe tignted to deLC'l'rninr cluded wit h 11 drterminl1liOll of t he ;1i I' 1 0 lHI s 11 nd th e t hr va lll es o f' ( \ mu ilnd ('D, ,,, . obb1ina ble at each flap

hin ge moment on Lire fl ap. po s ition. In these te t t he flap \\'a hin gr c1 at th r

.A sel'ips of LPsts with th p fl np set at 11 f ew selectrcl ce o te r of i ts l ead in g- edge arc.

nngles ,, ' as macle in t il e Y:l J'i ah le -d en si ty tu nn el to On the ba i of 1'e ult s obtainrd from t he forego in g drtel'mine th r fu ll- c:1 le c hn1'a cte l'i st ics of t hr airIoil- te t, a nrw hin gr flx i givin g reduced fl ap hin gt" flap comh inl ltio n drvrl oped in thr 7- hy 10-f oot wino moment s fln d opti mum neroclynflmic ch al'actr1'i st ics tunnel. Trsls wel'(' th r ll J11llciC' of th e N. A. C . A . 2:302 1 n t t he \T a 1'i OllS flnp-nn g lp sett in gs was sc lrct ed . Tl ll' nil'foi l with t he N. ,\ . C. A. 2:3 ()1 2 fi tlP , using L he 11n1(' modrl wilh tilr flap hin gp el about thi s poiot , dr sig l HlLrd hin ge-ax is IO('lltio n :1 S wilh t he N. \.. C. A. 2:30 12 nil'- axis 1 in (igu)'p 1 (b) , wa s u SN I in n sN i ps 0[' (in,ll Jo rce foil. Althoug JI 110 lrsLs of L he co mbintltion with t he tests to dete rmin e th e lift , drag, l1 nd pilc hin g- mom nt :'\. A. C. A. 2302 1 nil'foil wr l' r Jll; lcle in the 7- b :v 10-foot c hara ctl' l'i st ics of tllr nil'foil-fl11 p com bina Lion n t t hr lllnne l, nnalys i of th e dl1tn 0 [' ref er en ce 1 incl icntt" ci t hnL various flap-an gle srtt ing .. Th e test W('l'r con ducLpd tlrC' , 11Jlle flap Iringe 11xis wa s optim um fol' eit h C' 1' Ilil'foil. in accon lan ce wit h t1Ul (\nnl fOl'('p-te t pl'oc edul'e i n Th r YH l'i llbiC'-dC' lI s ily -Lu nnrl tC'sts c'ovr l' C' d 11 r nn gr of L he 7- by 1 O-foot wind Lun nrl n t 11 cl ynnm ic PI'('.. lI1'r o f R (' ~ ' Jl () ld s NUJlli>rl's l' C'p l' esrntnLi vC' o f thr l :lJH lin g- rO ll - 1G.:37 pound s prr sq unl'r f ool, cO l'l'rs pondin g Lo fl s pr r <l elition s of most m oclr J'll nirpillnes. o f 0 m i le's prr h oUl' in tanclard ail' . Th avrrngr 10del a rrall vrd for na p·load t ee t, in th e 7· by 10 ·f oo t willd tunnel. '1'he a irfo il mount ed Oil the ha lnnce; th e na p s epar ate ly s upp o rt ed.

APPARATUS, MODELS , A D TESTS test H eynolds N umb er ba. ed on th e l2-inc h c hord Th e tests were made dlll'ing the s umm er of 193 5 in (wing cho rd + flap ch ord ) of the model wa a pproxi- the N . ;\ . C. A. 7- by 10-foo t and var ia bl e-d en it y wind mately 730,000.

tunne l s. Desc rip tion of the tunnels and th e ta ndal'd Th e yaria tion with flap a ngl e of flap binge moment lr t procedure appear in reference 1 and 3. about axi 1 at a se ri es of ang le of attack wa deter- Th e model te ted in the 7- by 10 -f oot wind tu nn el was min ed by mea ming the twi st of a ca libraL ed rod n l'eclanguh1l' airfoi l of l aminated maho gany h av in g a attached to one e nd of th e flap, which for tbi test was span 0[' GO inches and a ch o rd of 10 inch es. Th e fl ap hin ged fr eely on it upports. For r eason s that wi ll was a d ul'11lu min airfoil with a span of GO in ch e and a a pp ear l ate l' , addit i ona l hi nge - moment mea u)'ements c ho l' d of 2 in c he s . FiLtings attached nea l' th e tl'a ili ng abo u t an axis sligh t ly ahea.d of axis I , de ign a.tecl ax i 2 rdg-r of lhe ai rf oil sLlp pol'Lrd the flap in any d e ir ed in fi g ure 1 (b ), weI' aJso macIe. Ail' l oads 00 the fl ap i tself wer e d eter mined by upportin g th e fl ap epnrate ly pO 'i Lion l' eh ltive to the 11i1'foi1. Th e . A. . A. 23012 in th e correct po ition wit h re pect to th e main airfoil n id o il model was Lhe one u cd for the tests described a nd mea min g force on the main airfoil alone. Tb e in reference 1; likewi e, the method of suppo rtin g th e flap l oad were then readily computed by d educting flaps, the program of testing, and tbe method of analyz - ing and presenting result were sim il ar to those of th e lo ad mea ur ed on the airfoil al one with the fl ap in th e co rr ect pos i tion fr om th e force mea med on the I'efet'ence 1. Figure 2 and :3 are sketc he s and photo - g l' l1phs of th e mode l ' . co mbin at ion in th e previous force te ts. Fi gu re 2 T e ts in the 7- by] O-foot wi nd t unn el wer e fir st m ade sh ow th e model Il rl'< lOgecl for flap-load mea m em nL s lo determine t he aria tion o f C a nd C 0[' t he in the 7- by 10-Ioot wind L u nne l. S imilar 111 as m e- Lm ar D min airfoil-fl ap comb in ation \\'iLh the rI ap hin ge J oc8ted aL m ents of fl up l on ds un ci hin ge mom e nt s on pliL flap s eac h of lhr pos it i ons sho WJl in fi g ul' C' 1 (a ) ; a sufficienl H nclF owlel'flllpS ;lI'r<l escl'iil rti i nr !' rren ('s -1 n n(\ !i.

AERODYNAlI1fC HARA TER I STICS Oli' AIRli'OILS WITH li'LAPS (a) (a) lIlodel used iu tbe 7- by 10-100t wind tuuneL (b) (h) Model lIsed ill the nuiahle-den,ity wind tuunel.

Jo"uL Hb~. The ' . _ \ . C .. \ . ~a()l~ airfoi l with O.Wr w N. A. U. A. 2~UI~ exlerua l·uirfoil Uap.

REPORT N ATlO ' AL AD \ ' I SOHY COM MlTT EE le OH AE l-W N A TICS nominal aspect mLio of th e model hn "iu g a spa ll of Th e models te ted in the ",uiab l e-dens i t~ T tu nn el GO illchl'S and ,l LoLal ch o rd of 12 iu clle wa s 5, t,h e co nsi ste d of t \\-O clllrnilimill airfoil s of K. A . ('. A.

r cs ults ha\'c becn eOJ'J'ectecl , mel : 1J' CpJ'csentcd f01':t p eL 23012 and N. A. C. A. 23021 eet ioll 1I in g 1\ .• \. . C . ~ \ .

mtios of G and in f -iIli ty. Jnfini tc ,1 pecL raLin daLa arc 23012 fla.p s m,lde of s Lainles s Leel . Th e SJ hl n of the flll'tller CO lTe ete d to a ll crrccti\ ' c l\ eyno ld s umh e l' to m od els wa 30 inc it e ,md the SU l ll of the wi ng ,1 ncl ll H ow for t h e e fr ects or n, il'- .' trCtllll turbulence, n.s ex - Rap chords, 5 in ch es . J1ln,ll hin g e h rackets (f ig. :~ ) phlilleo in rcJcrellces 7 n nd .

w er e used to attach th e n;1p to the jll,lin airfoils.

Th e daL,l obln incd in the \'< u'i n hk -d l'll silY lUllnel Standn.rd force Le ' ts wcre JIlade at a R eyno ld s Number hay c h ee l1 co rr ecte d in Lhe u unl 111 , 1I111 e l' ( I' eferc nccs :~ , of ab01lt 3,000,000 (e n 'ecti " e R eyno ld s t\ limb er a.houL 0, alld 10) . Th e rc s ulL nrc pre se nted for an aspecL ( ,00 0,000) of the cOJl1hinn tion u sin g tl lo ?:\ .• \. C . • \. .

I'fltio of G <lnd as se ction ( Ll ta. Th e section e btua cte r- 230 12 s ection for t be main airfoil wi t h fl ap nngl e;; of i stics, which llllye been cO l'l' ecLed Lo t h e e n'e cL i ve _ 3° , 20°, :30°, nnd 40 ° . Si mil ar tests \\ · ith f1 ,tP :Ingles R eyno ld s ]\ IImher and fo r Lhe en'ecL of r ect an g ular of _ 3° and 30 ° were m ade of t he com bina t ion usill g L ips ( refercnces 9 ;llld 10 ), fll'C di st in guis h cd fr om tIl the N. A. O. A. 2302l sect i on for lh e mnin airfoil.

\\ ' in g c hara cte ris tics h .v Lhe u sc of lowe r -ca . e l eLLe r s, Both co mhin,l tiollS \\ ' ere Le s ted i nv e rt ed \\ ' ith lh e fl ap t hu s: et at - 3° ( ang le for minimuJll dra g) to exte nd t b c ha racter is Lics through the neg 'lti, -c ·liIt mnge . ::\ Ll xi- mum lif t coe ffi cie nts w ere nlso obta in ed for both D rag clala ob l ni n ed in hoth tu nnc1s h n.\'e been corrected com bination s u t low er ",llue s o r th e R eyno ld s 1; lim her.

by dedu ct in g the dra g of lh e flap s up porLs, e timated PRECI ION from test s with dummy s upp orts. Thi c orrection \\ 'ns yel'y s mall , v arying in ma g ni tude from 0 to 0.0005 Th e pr cisi on of force an d load lc sts in th e 7- hy "t s mall a nd moderate va ili es of Lhe lif t coeffici enL.

10-fo ot wind tunnel i complete ly di sc ussed in r ef rence D etermination of optimum flap hinge axis .- R . ull s 1 ,4, and S. A di cussi on of preci s ion of force le ts i n of the fir t e l'i es o f te t in th e 7- hy 10-Ioot wind t h e var i able -d ens it y tunnel appenrs in refer en ces :~, G, tunnel <lI 'C g i" n in figure 4. Co n to ur s sh owing the and 7. It is heli c yed L h, 1t Lhe p r esent tes t re ult DI,IY vn ri at ion o f (l Ll/wX \\ ' ith flap pos iLi o n aL variou s flap be consi der ed free fro]l1 n Ily s eriou s cons is ten t crfOl' nng les appeal' in Lhe Ji g ur e, a \\ -ell a conto ur s o f a n d that they may be applied \\ · itb normal eJlg in ee rin g CO m,n witb t h e fI ,IP angle vH r.ving from _ 2° to _ 4° .

nccurac.I' Lo fr ee -fli gh t cond iti ons at the s tated yailie s of c fr ect i Ye R eyno ld 1\ umbel'. .\ b'llnnced hin ge ,,:-.: is for Lhe fl ap W<l S se l ected hy inY est i g,lti ng Lhe ch nnlcteristics of t he win g- flap (,Olll- RESULTS AND Dl CUSS lON bination with th e hin ge ax is n car t h e 0.25 Cf poinL For m of presentation of results. - All test rc s uiLs on t he flap , where th e fl a p hin ge moment lIould be haye been r educe d to standard nonclimensional coeffi- r e du ced to yer.v s mall va l ue. ~ \ profile o f the H ap ci cnt fo rm b,l ed on total \\ - ing arcn. ( sum of arcas of drnwll on t l'1lD pn ren t paper wa laid on t h e va ri ou a irf oil an d fla p ) a nd on total ch o rd C ( su m of cho rd of contou r s ll ects and r otate d abo u t euch of a se ri e or airfoil a ndllap ), e:-.:cept th e I1np-lo:ld oe ffi cien ts, \\ - hi ch hin ge axes n ca r t he 0.25 Cf point on t he fl ap and in are ba se d on the dimen sions of t be f1np it self . Th e v ari ous po si tions r ob Li ,-e to t he main n irfoil; t ili ..

pecial eoc ffi cic nt s u sed nrc d efi.ned ,1 S folluws : pr ocedu re pcrmitted th e a pp ro:-.: in11lte d etc l'll1inatio ll , ub sc ript W f efers to th e main air foil. o f Lile v alu es of CL II/ax a nd (l olllill o bt,linnbl e wit h the ub sc rip tj r efer to tlte fla]).

vnriou s 11X is locati ons. Hin ge ax is 1 (f ig. 1 (b )) wa s f inally sc1ected as g ivin g tbe b est cO lllpromi e beLw('ell C _ flap hingc momenl th e requirement of low hin ge m omenL, high L , lIlaT 11 [- q( 10+ Sf ) (C,c+ C f) an d 10 \\ ' CO lli in' Th e fl a p angle s fo r C n nd C o""" Lmax fo r ce o n fl a p normal to flap chord were 30° and _ :3° , r espect i ve l y, a nd th e lo ss of lifL -- qS f aml d rn g clwrncleristic s incurrcd by hingin g the fi np C [= force o n nap p Hm ll el to fl a p cilor0 aL t hi s ,lxis W,l witllin th e limi t of acc u nlC ~ T of Lllc c q " tes ts in boLh case.

Aerodynamic charaeterist i cs of selected airfoil eom - 0" ang lc hcl ,," ee ll win g and flll .p ch ord lill e'S, de g rees.

bination. - , L,lIlcl1Ll'd aero d. n <t mic charaete ri s Lics o[ lhe Cm (a.c.lo, pitc h ing-momenL coef fi ci ent co mpu ted ah out el ected n rran ge lllen t, as cietel'lllined in t h c 7 - by 10-foo t th e aerodynamic cen ter determined fo r t he nirfoil-fi<lp wind tunnc l, with til e fl ap ct nt ::mg lc of - 10 ° , _ 3° , co mbi nat i on " 'i th th e fI,IP se t ,It the minimum-drag 0 0, 5°, 10°, ~20 ° , :30 °, and 40° arc s hown in fi g ur es a n O' le.

5 Lo ] 2, res p ecL i, ' c1.y . , iJllii<u data for Lhe pl a in tandal'd cO lTe cL iolls for t he eH ects of jet-boundal' ,I' ~. j \. . C. ~ \ . 2:3012 airfoil used ill Lhe te L s nre ' hown and s tatic-pre 1I1'e gl'11clicnt in t he / - by 10- foot " 'inel in fi g ure t:3.

tu nn el wcr e app li ed to th e te s t r esults. . \. lLhou cr ll Lhe

AERODYNAM I CH ARACTER IS TI CS OF A IRFOILS WrJ'H F LAPS 5

It 'hould be noted th at the optimum fl ap angle for Th e r e ult pre e nt ed for th e erect and in ver ted C L'ui in g and hi gh-speed Bi g ht is n ot n ecessarily -3° te t (figs. 14, 15, 19 , a nd 20, and table I ) overlap to but may va ry omewh at with the lift coe ffi cie nt ome e xtent n ea r zero lift and ar e not in t ri ct ~ jO'ree CO tT e poneling to t hese spee d. T be optimum [In g le ment ; the pit c hin g -moment coe ffi cie nt a bout th e i' or l' ac1 l d e. ign s hould pL'obably be ci ete L'lllin ci by tl.C rociyna mic ce nter , t he po sition of the Iterodynamic fli gh L Le s L on <iC C lint I po iblc v<l ri ;:1t i n 1'e lilting cente l' , a ud t he v~ d llc given in tab le 1 for t he tift-c lIl' ve frOlll fi ll eh (a eLo L' a L he cf l' eeL o f a Lt itllde O Ll fu se hwe s lope, and for the ang le o( zero l ift ( indiC'aL e ci by t he a lld in LCL'i'er ence d L'a g, Lhe p fl'c cL or pik hing 1l 1O t llCn L Ii fL- c Ul'\' e 'lope) <t , obLailled fr om Lb e cr eeL and i 11- on La il d rag, scale e ff ee L, and t be v<l riaLiou \\ · iLlt lifL verted Lest difrer ollJewhnL. Th ese api nre nL di s- coe ffici en t pI' viollsly III nLioIl ed. crepallCIe in Lable 1 ari e from t lJC fa'L t h aL the - .,---,--, 0

o

<3 .... ....

c: & <U lJ lJ -5~ -5~ +--+----1 Q.

I--- + - i-;-;: =;ob,...+- I;-~ ---I ~ ;:;; (tl 105 lOS c '" ( b ) (" ' '' 0' : fl a p an g to , :10" .

0 o , (J <J .... ....

c: CIl ~ <.J u -5~ -5~ Q r--r -- ~-+~~-+ ---I Q ;:i, ;:;; (d) c '" (d ) eL .. u. ; fl ap aoglo, 400,

--- - ----- - --~~ ~~-,--, o

o

, c: CIl lJ -5~ r--+---i Q ;:;; (e) (f) 9 5 105 c '" (e) (.; L m" .r;; f]ap (l ll gl ,000 .

FI GU RE L- C'ontOUfs showing vari ation of CI .. muJ; uno C / i lt wi ib fl ap po s itioJJ ~ Hld Hll gl e. Th e r. A . . A . 23012 airfoil witb O . ltJc ,l' N . A. . '. A . 23012 external -airfoil hn O ap . Pluiu willg: I ~ m , a~, 1. 1 60 ; C l)m i ", 0.0 1 00 .

tanda l'd large- cale aerodynamic c hara cte ri s tic of p reviou ly m ent ioned co n t~lDt lltlv e be en el ected to give r ea onab ly good ;lO' reem en t wi th the tes t r s ult the . A . O. A. 23 01 2 airfoil with the J . A. 0, A .

at mod era te positive < md n egati ve ang les of attack.

23012 externa l-airfoil £l ap hin O'ed at axi 2 (Eg. l (b)) Th e har acte l' i st ic c urve may be faired toget h er at at anO'le of - 3° ( upri gh t and in ve rt ed), 20°, 30°, and 7. ero lift, giving pref erence to tbe po iti ve-a ngle data ; 40° a ob tained in th var iable-den it y tunnel ar c 01' tbe po s iti ve -angle d atu ma y b e mpl oyed in th e bown in figLll" es 14 to 1. imilar data for the imm e di ate n e ighborhood of 7.ero lift .

N. A. O. A. 23021 airfoil in com bin at ion with the

Discussion of airfoil charac teristics .- Th e high alu es N. A. . A. 23012 exte rn al-airfoil £l ap et at ang le of the m a xirnwn l ift coe ffi cien t o bt a in ed, 2.37 (or t he of _ 3° (upriO'ht and in v rt ed ) and 30° app ar in EgLll"e

. A. O. A. 23012 airfoil with £l ap and 2.41 for the

] 9 to 2 1. Important ch aracte ri tic of th e two au,foil-

. A. O. A. 23021 airfoil wi th Hap at an e ff ect i ve R ey-

flap co mbin at ion te ted in the va ria ble -den s it y tunne l nold umb er of about ,000,000, com pare f avora bl y are lImmarized in ta bl e 1. with tho e obtained for mo s t othel' hi g h-lift devices.

6 HEPOllT SATIOS .\ L .\ l)nSORY

CO ,\l i\ fl TTEE FOR ' ERO J A UTICS .12 I I

~

L . /1 ,

[ r-

I /0' f , ~ .10 ~~~-+-+ -r~+-~ ~~~ 40~ 2.0 .40

·

. , I-+-++-+-+-+-l f- ~ , I

: · ! IT I} nil : . : :~: ~<: --- -f-f- : Ij' ~, H, I~ ;:i

. J t I I , , I 0 ~ - -- f-f- rc -tr: ~ .

. Ct j . , I . '" 14 .28t·g .07 '-,--f- ~~rf- " ~ ~ t: I- j ~ 2 8 Ji

t ' j "' 1-., .. 1 I 1 + .Q)~ I .....

j ' j . , ~ ~ , 12 -J.24·Qo ·06 ; I f--+ t --- ---r-I-+- '+- 24e

1 ~ ~ \) ~ !- ~ +-, ~ • H- t u

'~ Ei lni ~ ~ J; t ~~t-fli lU~ l ~.! ~: ;~~

'i-t-d r ~Vr ,. "I, ~

. 0/ .2 .U4

-f f , ~, ~ T :L LL ..L . :- .-t -, " I 4 g

o ...

. "I---'- ' ,;y , ~'· Z)".· \ ' , c:

o Cll o o o 00

~

U

. U

"- l o Atrlot! NA.C.A. 230/2 " / " I fl' '1' <j "- .I ./ .L 'I >- I. , -4 ~ -.2 - 4 OJ 'Stze:10-x60" Flop. 2"x60" l j,. t I ~-- ~ , 0..

.~ Pres. (sInd aim.): I <11-. l- - L~ Atrlo/rNA.CA. 230/2 -.4 2 ' I-a ~ Tes!edL.MA.L. Dole: 7 -13- 35 - 8 ci.

o t Flop. NA.C.A. 23012 Ve/(fl./sec).II7.3 R.N 730,000 U f J- ! Tes!. 2830 7 by 10 It. lunnel 1- 12 · Tes! ospecf rolio, 5

t -3 ~ ,r =f R.N:{effeclive) 1,050,000

Resulfs corrected to AR . 6

Q) L I I Resulls correcled /0 infinile

Tesl 2830 7 by 10 ff. funnel ~ -.4 1 aspect ratio. Dole: 7-13-35 - /6 Cprrefled for lunnel - wa ll, e ffec I.

~ ------1-- L ---I- -,.4 ~2 0 .2 .4 .6 .8 /0 /,2 1.4 - 8 -4 0 4 8 12 16 20 24 28 Ang/e of att ock, IX (degrees) Lift coefficient. Cc 'T 'I1(' :"\ .. \ ( ' . .\ . ~:iOl:! ai rr oi l willi O. :lO (',r :-.: .. \ . c .. \ . :lalll:1 ('\It'rrlfli -a irf nii flap . Flap ang le , - 10 ° . T he airfoil is thc5alllC HS II sed ror 1(' <;1. :t~:SI 11 (fiJ! - f i).

('\('cpt lilr fl ap !'l' tlin g. Thc \"ed lll' ur ( 'mel/_r,)u i:-; <'olllpilled ahoullh c il('rod~ mlllli( ' ('enler lI sed ror tCl'\t. 2831 -a .12,....---, r 48 la .,c.

,

r' ~ , ~

~ . +== --t--Jj-' -t-r--t-_i t--t--t -t-f--j-r--l

.11 44 ~~

-------

, , , , .

41 .. --+- ,..--H- ,-t-H- 1--- r- r; ! :

,- ~ f-: 1--1- I- ·H-+-+-l 4 0

./0 , ? 0 ~ , , , .09 -t--t--t--i 36 ~ \.

t I .36 1.8 0-

.'

I • f I 1--f-f- 32~ 1.6 . , • j ,

1 1.4

-j A trfoil: NA.C.A. 23012 "- r-- i -r- - 4 0 S Stze.IO"x60" Flop: 2"x60" ~ • Pres. (st nd olm.): / -.2 - 4 ~

i Tesled L.MAL Dole . 7 -13-35 ~ -.2 ~ A Irlo t!. NACA. 2 3 012 -a g-

8 I- Flop:NA.C.A 23012 D ole: 7-13- 3 5 '"

I Vel. (ff/sec)-I/7.3 R.N' 730,000 ' - . 4

-8

Te st aspect rollO, 5 -3 J 1-1-1- T est. ' 2 8 31 - 0, 7 by 10 ft lunnel

-12

1 t -. R. N:{effecltve) 1,050,000

• Resu/ls corrected fa A.R . ~ '" r- r-r-r- Res ults correcled 10 Infinite Tes!. 2831-0 , 7 by 10 fl. tunnel E ~ 4 ~ aspe ct ,: o tio. - O 1 C()rrec led for lunne{- woll.!!Jfec I.

~ . -6 '-----'- -;- -'- 4 --'-- 72 -'--'-----' 0 -- . .... 2 -- .4 '--- . -'- 6 .8 /0 1.2 /, 4 /. 6 o 4 <'1 12 16 2 0 24 28 Angle of ollack, 0' (degr e es) Lift coefficient, Cc _ :50 I -- I ap angle . _.

Pi\ 'o t a rt nap leading- N lgc O.2:'k, 0 . 011 7,.

\ l ain wing ~fi'l'lio ll :-;. \ . ( ' . . \ . 2:\011 I'i ",,( helo\\' lIap ('hor<l _ . I<kt .0 16; r o Flap sec ti on 1\ .. \ . ( ' .. \ . 230 12 I'lap rl i~ p I H(,(,I1I(,lIt ane:le _: i .\ Jain win~ ehorel, (' 1/ o. ~:l:lr (fl. c.)o rr (, lII J (' a din~ rdge .

. ~ l iie Fla p chord, c,= O.2('" . If i(lic {fl. f '.)O nh(wc m ain wing ehurd . C8 H at UI11 l' horci , C=Cu+('1 ( 0 . ('.)0 &l 1TI(' as ror "~ r iahll:' p d('n l'\ il~ ' ! I mlle l lc ~ t 12i3 (fip:. J I) w it !lout Ph 'o t art t railinf,!: edge' "r (' <t _ __ O .o:!~r" .02 66< cO ITcc lion ror rffeel or I'cC'I Angll la r lip s.

Piy ut helo\\ main \\ ing ('110ft!. ____ .0 5 1 <. ,0 4 5c YII ; l' I<E (j. - Th e N. ~ \ . C . .\ . 2aO l 2 air foil \\'ith O.~'!Ir. N. A. C. _\ . 230 12 c .\ (erulll-airfoil fl a p.

AERODY J AMIC CHARA CT ER I STI S OF A IR F O IL WI T H FL P .12 r--' la .c. ) 1 I I - ~

f--+ I -R=~

a ----'----,. -.!.. I

. I I -t-:- - 1-1- +

T

~ ; f- f-

-r 1

40 ___ I I f- f- f- . 10 I I- f---- .-

I f- f- -~ 2.0 40 H 1-1- ~

I 1)' ~

~-r-r

f-I- -- -I- f- I

I.. o9 H- 1- l- -

36 ~ I o

f- I-I- 1-- I-I- ,- 3 6 cJ f- I-I- 0-

t- t- /. 8 ~

L

11 - ,- +

"" .08 - I-I-f- 32~ ';..

o - ZO 32 c: f- - 1.6 ~ .~

"tJ +-1- ; 1

'-f-, . \,! .0 7 H-t--f--l +

28 ~

c: .Q '-1- 1,4 ---;-

Z8 (jJ 0 28-.: ~ r-r-

....

1 I

~f-

-l- + t

. ~ ~ . 06 ~-+-+-+-4

- 24 e

~ f-- 1--' 1 .8 e LI- r

, v

I

c. p. I- -.-I -0-;0- c4 ~ cO 1. 2 cJ.

I.. 1- ' I n -= -=;r ~ - 20<l? 40 I.O§ .

f L 7 JJI\ I-t1 I-f- rr

C:) to '- ::H: ==-~=· ~ f"· ! i I if ~ ::!

=1 -

. \,!

':= ' :v. / .

16 0 ~ -- - I ~

'-.l 16 e 60 .8 ~ .

Q) I l\..

cj, ::::. / -_.

Y-:. e~ --I .6 u.

~ 12 ~ 80 1 - -

~

"ti 0 :: I; t:; =: . ~ I j r ~ ~~ ( :~

-

- 1/ :t

-c I- .4 " .

~ 8 ~ 100 7 1/ "-

.a I r- C- +-,. - c:" '-""-~ :::.t- : " l- i fil+ 4 "5

'!:: 0 -::

.L'

1- f-

.2 f- f- I-f-I- I -l cd . - ~ l-J J 11 f .2 04

1 \

f-; I II

'" 4~ o Ql u r ' " ~ " :7f"'T ' > { , ' I ' """-,7 ·1 I 0 o r:" mr

:g O ~

Airfoil NA .CA. 23012 I I -r l C '<' I' 1 I I I ' -4 't

I- f-- J -. I I--+-+- -l- .... ~Lcr -l-

o 0..

tt l- Size:10 -x 60 " Flo p: 2"x 60"

-" 1111 Ir~ 1 1' %, Q:: -4 . ~ - . 2 1 1-1-1 ./ Pres. (sthd otm ): I V ~ -. 2 H H-I--l-+ -+Airfoil: NA . C.A. 230 12 - 8 ~ Tested- L.MAL Dole: 7- 13 -35 ~ o F/o p:NA .CA. 23012 Dote: 7-13 - 35 Vel. (ff/s ec.): 117.3 R.N: 730,000 -. 4 - 8 <.. ; Test aspect rolio, 5 ~ - . 3 Test: 2832 , 7 by lo ft. tunnel ~ -12

r ) ~

c: RN (Effect iv e): 1 ,050,000 Results corrected fa A.R. 6 / -f- ., Results corrected to rnfinite Test: 2832, 7 by 10 ft. tunne l f-- ~ -. 4 aspect ratio . - /6 Corrected for tunnel-wall effect.

dk

~ .6 -8 -4 0 4 8 12 16 20 24 28 .8 1. 0 1.2 1.4 16 .4 .6 o .2 Angle of attock. {'( (de 9 r ee s) Li ft c oeff ic ient, G.

jo'Wl ' B" i. The N. A. ( ' .. \ .2 3012 airf oil w iLh 0. 2Oc . N . A . O . A. 230 12 e.\ le rll al -ai rfo il lJ a Jl . 1 "1" 1 ) a ll gle. 0° . The airfoil is the SAme as used for test 2831- " (rig. Ii) except tbe fl ap s ett ing. ' rhe value of Cm « <.C.lu is CO lli Jluled abou t L ha aero dyn amic center used for test 283 1- 6.

r- := - r- ~ i :U "': (al' JJ ,/2 '-'--'-~--'-- I _ "T"+ -'-1 -_~.j-- -T-+ - _~ I- "T" + -' -1 - _~ .j-- -T -+ -!r-T'I ~- -I -r 48

Gi- :--- ~ . I I --- - I -I + ' J

- t+ ~ ~~ ==-; t--1 '-'1

"" ~ I ~ .IO I-I-l-l--l-H--l-l-I-t~ -, ~ 'l 40

~oo _ _ 1· t 1: +~--~-=,:-~~~=-.+--~ ~: : :: .09 H-f---f--+I-+--- I -~f-:::1-:::~f--:~--:~~~I:~~I:::-:::I!~-Y- I :_=- 36 I

r .0 8 f-+-I--l-+ lit 1-1--' 32~

~-co ~f-~ .. I- t t f-+ ,. j-f_ /.6 . 32 ~. 0 7f-f- _ f- ~.'1-'- --+,-- -+--'-If--+_-1--~-+-1-_-:"_:--I-I~~~1-1- 1 f- _ f- 2 8 ~ u

28"0 ,- 0 V t -1 ~ C 1- I 4 28 ~ .~ f-t- ~ . S! -

L

0 »..... t ~ .06 Hf.-I-+-+--I- f- f- n -f-f- f- 2 4 ~

Z4 ~ 20 1.2 r ~.24.'!!. ~ 1-1-1-+-+- 1 ---1---1--1--1--1---1--1- • LID c p 1 .1 '-' (l) I ~ ~ ~ r- ... : ~ 0 . OS I-H-+-I--l--I-H-+-I--I-+-+--I-HH--l-- \ ++-H L'O ~ ~ 20 to 4 0 . IJ I I f- I. 0 ~ .20 'Qj v 1-1-1-+-+ -1 ---1---1--1-+--1--1- -I--I--I--1--+-I---I~ U - f-f- 9- '-l 0 . ,, 1/ - 0 0- 0 v, • l.. J ;g v o · 4 16

r:t :: ~"=:>- W f 'll t~1t .'+ . , :!;:Ii:; =,==~H -rr>->-' >- . -- &~ ? '~. 12~

'l: V j J t ' '- 1 I I ,"Pr- , F:::l ../ 8 I..

j :1 °;: ~ ~ tl #f j '- ~~ ._ ~ .: 0" : :0: '0: -'-,,- I 1 %" 1 1f T II :i

.... ,-f / f.- Ir 0 1 : NA .CA. 23012 I r t _. 1 ;' P _I .-"'--1 j _

l -4 ' !:: fL l -f- Size: 10 "x 60 " Flop : 2 " x60 " ..., _ .-"' rr C .• ,', I' --'-'-' .!!!

. / Pres . (stnd aim.): I -.2...: /' 0..

>l. I- Tested- L.MAL Dole : 7 - 13-35 J (l) -. 2 -'1 ___ A irfoil : NA C. A. 23012 " 8 c _ {j <.. i ~ /. r- f-f- Vel.(ft./sec.): 11 7.3 RN : 730,000 - . 4 0 ____ F/op:NA . C.A 2301 2 Oote: 7-13-35 - " i':.... Test OSPflcf rofto, 5 ~ - .3 _ Test · 2833. 7 by 10 ft. funnel

- 12

_ Results c orrected to A R 6 1 c: _ _ R.N (Effective): 1 ,050,000

~_ Test . 2833, 7 by 10 f t. tunne l ., Results correcfed fo infinite ~ -/6 Corrected for tunnel-wal l effect . ~ - .4 - -- aspect r a tio .

J

8 - 4 0 4 8 12 1 6 20 24 28 ~ L -;: -l. 4 --'- - - . 2 '--'- - O .l- -' .~ 2 -. ~ 4 -- . 6 ~- 8 ~- I. ~ .0 -- /'2 ~- 1.4 /.6 Angle of att ock , ()( (degrees ) Liff coeffi cient. C L fl(;l l HE 8.- The N . ,\ . C. A. n012 airfoil witb O.2Oc w N . A, O. A . 23012 external -ai rf oil [l ap . I" bl) angle, 5° . Th e airfoil i tbe sa m e as used for test 28.3H. (fig. 0), except tbs fl ap setting. Th e value of Cm(".c'>Q is co mputed abo ll t the aerodyn amic center used for test 2831 - 0.

REPORT NATIONAL .'lD YI SORY CO i MI TTEE FOR .'lERONA '.1' 1 .12 48 I I I I I I .11 '--' I I . 10 I I I II I I I I I .0 9 I I I

1. 8 . 36 .0

'I I ....: .0 8 - I I I I 1. 6 .32 c: . QJ I G .07 I I I 1 4 .28 q ~ 1 I 1 ...: ~ .06 I I I / 2 .24~ u I 1

~--+--+--1 Q g- . 05

I I

r--'-----'-+ =r ' A--l- -r= +- J 4-- r-·-~ F =' ---+----l.-t---1 I. 0 . 20 ~ -6

I !

-J 0 ~ . 04 ~ .8.,.:.I 6 \)<;::

~ is ~.0 3

-1 I 1 "- . 61,/2~ It: I ~ ::t . 02 f'r .4 ~.08 4, " f-.- ....., ......

f-- ___ 4 u .01 .2 SO .04 -..J

o

ja' , ~

o o

,.

-. Ai rfoil NA.CA. 23012

V

, -

I J -. I

- '-/'/-.- ----.---1 Size: 10 "x 60" Flop 2"x60 "

PI" 'T l ----r

Pres . (s f'nd ofm). I I r fm l i" /

1 - II

~ ...P" I

- I+-/ -~-l TesfedLMA .L . Dole. 7-13-35 'i -. 2 , .-

I I I I I I I - . 4 o Vel(fl/sec.):117.3 R. N: 730,000 -8 \) A ,rfoll'N ACA 23012 . F/op:N A .C. A. 23012 ,.-l-+-~-I Tesf ospecf rol,a, 5 ;... - .3 Test: 2834 , 7 b y 10 ff tunne l Resulls correc fed fo A R. 6 c: QJ Dole: 7- 13 -35 R .N:(U r) 1,050,000 -+-I--+--t-i Test. 2834, 7 by 10 fl. lunnel

, ~-=q=

E - .4 - 16 Results correct ed fa mfimle aspect rat io.

f . , Cqrrecfe.d for fLm{'el- w2 11 e/f§c ~ 16 1. 8 .2 .4 .6 .8 10 12 1. 4 -4 0 4 8 12 16 20 24 28 74 Angle of ottock, IX (degrees) Lif t co e ffici en t. C, ]o''' il'R I, n. - The ~ . A C. A. 230 12 airfoil with O.zOe. ~. A . C . . \. :1:10 12 e.\l.c rn a\-', irf OiI fl ap. Flap an~le, 1 0". Th e ai rf o il is the same as u se d for test 2.'>:lI - a ( fj~. U), e\('cp!. I he flap ~(' llin g. The Yaluc of (''''(''J .ln is (,O TlIPIJl (' d aho lll t he ncro<iy n alllic tonter used for te ~ t 2-83 1- <\ .

.12 ---- 48

r-

,O C >';--

- ~ J

:-~ . -

~ t-- ..........

.11

+ ~ + 44

c -

. -

~ ti + --'- l-

~ .44

r--"I + . 10 40 ~ 2.0 40 l

~

o .09 36 QJ ..c: I..

u

+ + I~

1.8 .36

.... f

,

o . 08 '"

32i

\) -l

~ I ~ i I

1.6 .32 c: • j QJ 28 tJ ° t.S .07 :g' 28'E 0 1.4 .28 l ,o o .Il! c: .06 24 ~ 24 ~ 20 , 12<s24~ .~ j t ~ ;...

-l: '" Q; ~ .05 20 ~ I ~ 20 ~ 40 --- .- +- + -i I.O~ Z08 ~ 1 • ~ ~ 0 J- I} 16 Cl . l t .U '" u . 04

8' 16 ~ 60 f-t

8 ~ 16 Cl '" ~ . . l Cl l 'tl ~ ~ <:::lis 03 12 ~ u 'tl 12 ~ 80 .6 .12 ~ ·S .f? -S ~ ~.02 8 I..

.4--J .0 8 0 ~ 8 '0100 ~ -;.. 4 I ~Ol "-

4 '6

o

4 £ 120

2 . 04 Cl o O--~ ------~-- --~ ~ ~~-L~~ ~~ O~ ~ o QJ ---t-----t ~ J "\... o

o

Q.

~ Alr-foil: N A Ck 23012

r 0

, . - ~ - -4 .S; <.': : -.1 size' 10"x60" Flop. 2 " x60" • j - - - _C ""'<1'0 ~ -4 I::. Pres. (sl'nd aim.): I -.2 ~- TesledL.MAL Dole. 7-13-35 Il! .2 ' -:- ' 1' -- : -;- ~ ~ : -:::> -8 ~ <.: o Ve l(ft.sec.):117.3 R.N. 73 0,000 - 4 -8 u Airfoil. NkC.A. 23012, Flop: NAC.A. 230 12 ' - 12 Tesl aspecf ratio, 5 '\.. - .3 Tesl: 2835, 7 by 10 ff. tun nel Results correc led 10 A R. 6 + ~ Dole: 7 - 13 -35 RN:(£ffective) 1,0 50,000 J Test: 2835, 7 by 10 ft funnel

g-4

Res':!!s ~~cte~ /0 mfmd e ospe<;f rof,o. rl 6 Correc te.d for IU!K!§.I- 1'1.0 /1 ?,f[ect .

~ -:2

o .2 .4 .6 .8 10 1. 2 14 16 /8

-1 2 -8 - 4 0 4 8 12 16 20 24 28 Angle of attock, r{ (degrees) I. Iff coefficient; C.

FIGURE 10 . Tile N. A . U. A. 230 1 2airfo il with 0.2Oc ;\. A , C . ,I . 2:l012 c\!.e rn al-a irroil Oap. Fl ap alJ~le, 2() 0. 'rhe airroil is t he sa m e as us ed for Le st 28:!1-a (n,(. Ii) , c.\cep!. the v fl up set tin g. The "a lu c of C'"«(I .("')O is comp u ted nho llt tile aerod Ylla lll ic l'clllor u se d r or test 28;3 1- a.

AE ROl)Y AMrc C HAR ' rEm ' l'rcs OF ATRFOTLS WITH FLA P Lr- Ill' , a c lo..j H--+ III 30 ' . / 2 .-----.---,-I-,-I---.--,----,---.----rI--,--.-t,--,--H--.----rr-~,- +-r- +-'--'-+ --r -+- -, -:-...;--,----,H I r-

- < 1. -1-+ t-- t ~ -l::::L."""' J . II I II T+ t '1

f--++-t-t- H := II~ ill~t ! [ ~'_L L ." lOr- l- ,I I H-~-

40 -:--., 1

~

36 ~ t ~r- ~ W l ~ c ..J 20 40 .09 I I·~t r-

0-

r-r-

-S 1 -- CLI-1 ~ \ -- --j 18 .36 0° 11- Im-l ' -

Qj 32~

"- Y r-. - (j .08 _ ±t-t L'=: - t' 1--1-++-+-+-+-+-1

~ 0++- - L ~~ / t C , J j ,'632 107 L- ~ f--; .. !J-=:-~t--t+--++-t-+-+-1

28 .

:2

.-'-

r- 24 e

:: L: ~ ,, 1 4 F~ r : ~ ~ fT1 ;; " :: j 1 061-r- -j---: __ II---+-t- -+---!-+I -+--:]--l~-+:---L""; _1--·I--I-I-+t~~;=_+~=::~_+ _=:t- ~=::=:: ""

, I / 1 Ie - '\, --+- .... ' :::: g-.05 I 1+- cO ~

~ 20 ~ 40 rl -t-+-t--t- ~. P . ..- .h b , " . I.O.~ .20 ~ is H ---:I--'---+-+--j-+--:-'-- ---"I-t-+-t-+~ _ C ;'-- ~ l -4 0 H-+-+--+ L -b rJ;{ "i----+,-+ ± - r _ - .\,! 1I 0,.04 I I I I c. 16° (j,16¢:60 - V . 8~ .160-i;: II I v {' ~:;;- .d L/ lJ -- ~ e 0.03 I r-- -.... . ... ......,. 12!i.

'ti I 2 ~ 80 i"-- / - - . 6 1I . 12 r:::, ct: r---. 1 1 YI< .f; ;: 8~/00 - 1/ -- # r-- '-r-- -- $ .02 I 1 --- -l~ ":" -+- + :'- j t o tX 8l.

~ ~ H- /li -ff-- +-+- V -l h-++--j' =--t- --,--·,--+ t---- .4 -.J .08 , + - ~ - 1 Dr- .f>

~ -Z - -1,' /- ,, / " : . '\. I I j - - . a I 1 -+---: -+-+ 11-+-+-+ I--+---+- + +2 4 . J-"J T I-- 4 "5

.~ 4 § 120 1--i r;.. ~ c;, L +1 '-f- - .2 .0 4 a I I 1 - -'- 7 I o~

0 0

~ 0 ~/40 Ai rfoil' NA C.A 23012 . F -. I ~ -----L- ~ ~~ ~ • - I I II I , -4 ~

L--j--+,-+~-+-- IS i z e :IO"x60"Flop:2" x 60" - I ' ,/' ~ -4 f; H-+-t---l- c- Pres. (st'ndolm.) : I -.2.; ~ :;..-/ -; ~ ~ ~ --+--+-+- - 0- !:i, L+--t-+--r--- tTestedL.MA .L, Dole : 7--/5-35 (lj-.2 , _ . _____ --- ~ ----" . C - -8~ _ I.i V. I. (f.t ~ ) 1173 R N 7.'30 000 4 0 --~ ' - ~ --.,--- ' --;:- - , - ~ ~~.'!

r-+-+--'---L-t--t e. . ,sec.:. . .: ,-. U , ~ . -=i<~ , - I -,- H-f---'-'-'--t- -! Test aspect ratio, 5 -.3 --'----"- ~ - ~ ' . - ----L. .. ~ -/2

r- Results corrected to A.R. 6 ~ A Ir-fol/:NA . C.A.23012 , Flop NA.C.A. 230~/2

'_ Test: 283 6, 7 by 10 ft tunnel ~ _ 4 Test. 2836 , 7 by 10 ft. tunnel, R. N: ( Erf) 1,050,000 16 Corrected for tunnel-wall effect. ~ Results corr , ecied to mf,rll'fe a s pecf rq/io . -- -12 -8 --4 a 4 8 1 2 16 20 24 28 a .2 .4 .6 .8 1.0 /.2 1.4 16 /.8 2 .0 22 Angl e of attock , C( (d egree S) Lift coefficient. C, jC, (lL ' HB ll.- ' rb e T, A. C. A. 23012 airfo il wiLb 0.20c. N. A. C. A. 2'30 12 exLernal-airfoilllap. Flap angle, 30°. 'r he airfoil is the same as used for test 2831--8 (fig. 0) exe pi tbe n ap setting. ' rbe value of Cm(a.c.l is computed abo ut tbe aerodynamic ceuter used for tcst 283l--a .

o . 12 [1

I-+-+-'--l---t- -I---- -- ~( a , c } oT r n f 1

40' .11 ;'

~

I . /0 '" :0- I -1- • 2.0 .40 '-0 !-. -r-c- _I I I . + r-c- .09

I

.0

.36 ~ I _I I I o 1 _L .,., .08 j..

"tl -'-- + --+T I--'- /.6 .32 c: I

£ + LI-i-- C" <q . -----+---.,- ± .(lj

~ L ~ ,g .07

281> 0 . -1'- \ ~-~ 1.4 . t Qi I

a 1 .2! (; .06

~ 24 ~ 20 i I r-- I L ._ ~ :; 1 .2 :.24 8'05

t

~ 20 E 40 c p ,l--/' - ~ -~. /.0 ~ . 200 is

8' ',g ;.~ )' ~ -- ~ r , ' . ;g~,4 .04 '--+-

il -:; 60 V I/ 7 i~ ---: . 8'Q:,./6~~ ---L~

f---l -t-+ -I If- -+- --jl- +-+- ./ c. ~1-- - - - 1- '- - 0 r:::, l. .03 u ~/2~80 / , D -- --- - .6 .lc . Cl...

~ ~ L ~ I ~ .0 2

~ 8 '0 100 H-+ +, /t L /~L L.: - =-'-l-..;!-I - .4 -.J .08

0.... ....~ ~ L/ D f-H - -f ~ ++++-+-H .01

4"5

. 04 ..g 4 ~/cO HI .vv,, + -+--+- + i --Ll+-t l -t-_+. +-H '- ""' HH-+-+--I .2 -l?

~ t I I I - - t-- -'-1--1-+--+--1 0

a

~ "-

a ~/40 Airfoil' NA.C. A 23012 °

-- 4

J -./

__ 4 .!: 160 ~;ze: I(Ot·~6dO" [A)oPI: 2"x 60" - .2 ~ 1 I ,-res. S n . O lm. : 0- ...: s:i, r-' i -- - Tesled-L.MAL Dote: 7--15-35 Ql -.2 - 8 ~ --8 1--1 I Vel(ft.j sec.):1173 R.N: 730.000 - . 4 u -+-t--+- --I Test aspect ratio. 5 .... -3 ,..:;-- • I Results correcfed fa AR . 6 c Ql .--_1 I I Test: 2837. 7 by 10 ft funnel

g - .4

'-- --o--'---'I_-'---I :-Corre cfed for tunnel-wall effect.

~ -: 2 --12 -8 --4 0 4 (j 12 16 20 24 28 Angle of attock . C( (degrees) Fl ou tt, ; 12 .-' rh e . A. C. A. 2.1012 a irfoil with O .20c" r A. C. A. 230 12 cxtcrnal-air f oi l flnp. I' lop angl e. 40 °. 1' he airfoil is Lhe some as used fo r test 283 \ -- a (fig 6) except the fl ap se ll iug. The va lue of C"(a.c.>o is romp u tcri aho ut t he ae rodYna mi c ce nt er used for test 2Il31 -- a.

10 REPOR ' I' A'1'IONAL A DVTSORY 'O MMI ' I" rEE FOR AERO I A 'rI CS

. 12 48 I

I r 1

I 1 1 . /I 44 I I Te st .10 2392 Ll - I

r l:J r

0 .

° • x

I 28 13 "' 17 0 I c: . ~ .0 8 f-._- . 32 u 1-- I- f-

Lt"T~ --+

'i i-

:O~

- - 1-- ~ .07 14 .28 ~ -t- l- I-

~ '=c

• u .06 I-

"' + .ti t

+

+-- 1.2 24 -..: g-

t

. . ~{j.05

'Tt r-1 ~ - -!

Y :::;~>=f =l'~ "f'- I 0 ~ . 20 ~ ~

~

., .. : ~ ~ .04 tt'! ;«0 F r- l- I-

+

.8~.16 °u e

" 0..: ~ ~ 0- .03 I I --- .6"- .12 Cl r-

H

-2 ~ ~ .02 i-'-r- -

~ t-t-

V

ED

~ .4 u .08 I -r---r- t:-

, P9j:::: lj:d

-::: ....

-R o, 1- I-I-

" .01 f- "- c: po 1 1 ----:;: I I . 2...., .0 4 4u I I I I 1 V I g <...

o I\) o ~

OQ. o d

~i - c fT

~

. ~ - -. I

~

Air f oil NA C A. 23012 "-

- .2 1 - ~T ~ !-~~t

I\) - ",t ~ " S ize : 1 0 ' x 60 "

8 -.2

>- C-~ . . .. I

"- Pr es ( st n d aim ). I :t~ 1 -:U _ -- 0 1 ~_....L _ ~. I .

- 8 Te s ted-L.MA .L . Dole: 6 - 13-35 - . 4 A ir foil N A CA . 230/2 Dole : 6 - 13 - 35 ~-3 - /2 Ve / (fl / sec ) : 11 7.3 R.N·603,OOO Tesf 2392 , 2738, 2 740, 2813, E: - -.6 T es t. 2740 , 7 by 10 ft. funnel 7 by 10 ft lunnel. R N . (Er!) 875, 00 0

~ r J

- ~-.4 Co rrect ed for f unnel-wall effect. -1 6 R es u lts co rrec l ed 10 m f md e as pe cl ro l io 1

j

it "

o - 4 ---- 8 --- 12 --- 16---8~0--2~4 -- ~2 B ~32

-8 4 --: 4 -2 o .2 .4 .6 B W ~ U ~ m

Llff coeffiCient. ( ~ Angle of allqck, a (degrees) l "WURE Ja. -' l' ho '. A. C. A . 23012 airfoil.

,....,- r 1I . C .

- -,- --- , --~ .-~-- - -- ~ -+-1-1-+.-1 40 .10 +- t

lh- ]'

Vi' 36 ~ ,{ 09 .44 ~ ~ .,... . 08 32~

r ~; iT 1

'-"- 20 40 .~ +-1-1-+--!--I-I-+- 28 ~ .\3 .07 ' ' I.B 36 ~ 0' -...

Q) ~~HH-+ -+-+ -I 24 '-t

r ~06 1

I ; , ..

1.6 32 . u <...

~ I\J

~ g-.05 -+++++-!--!- H cO u

I\J , I 1.4 2892 {j 28 .g> 0 C\.

--+-+-+--1 I 6 ~ ~ ~.04 i3 24 Cl 20 1.2 _" .2 4 ~ ~ I '-..l 0 0 03 ~ 12~ .... - u <....

~ c::: 20 ~ 40 1.0 ~ . 20 0- 0..: S 8 '

--: ° :u p .02

. .:: <...

~ 6' .8 1\).1 Cl g- 16'1; 60 ~ o .01 <... l..

4",,- .60.12 u ~ 1 2'i 80 -2 u ~ o~

'-

o .4--.J .08 ,. - .1

-4 '0

.2 .04 ~

-8 2'

o 0 ,kfotl N A C II 23 012 - H N 3, 110 ,000

"

-/2 Jze 5 x30 Vcl(fl/sec.j 69. 7 _ 2 A lr f od NA CA. 2 3012 with ex terno l- p,ps.(st'ndolfll.j.2o.7 Oaf. 7- 2 0- 35 .

air f oi l flo p . HN'(E ffecflVe) 8,210,000 -16 T cs t edL MA L Te s f : I/.D .T 1273 Do le : 7 - 20 -35 Test. f./D.T. 1273 8 Co rre cl ed for f unnel -I'l oll effect -.4 Res u/ls c ~r rec .' e d I ;; m ftj 7l fe ~s pe c f ~ o -8 -4 o 4 8 12 /6 20 24 28 32 --:4 -2 0 .2 4 .6 .8 10 12 14 16 IB Angle of aflock, (( (de9rees) y Wit h ex f ernal a Ir fo i l flop. L ifl coefficient, c, __ _____ _____ _ _____ _3° Piv ot below main wing chorrL __ -_. ___ o. n5· (c " O.045c }' l ap a n g l e ~ __ __ . 24c , .040c _ l' .. \ . C. A. 23 01 2 Piv ot aft Oa p l eading edge . _ ]\fain wing seclio lL __ ___ 1\ .. 1 . C .. \ . 23012 Pivot below fi ap cho rd ____ Flap section . __ . LOCI .0167c 0.833c Flap displacem en t ang le _ - -- --- ----__ _3 ° 1 1ain wing chord, C Il a. c. from lead in g edge ___ _ . 16 67c Flap cbord, c/= 0.2c w . -- -- -_ .2'JOc a. c. a bo ve ma in wing chord --- -- ___ .04r Datum cho rd , C=Cw+CI __ ____ O. O:J c. .025c Pivot a f( (railing edge of c" FIGURE H.-Tbe N. A. C, A. 23012 airfoil with O.2Oc~ N. A. C, A. 23012 externa l-ai rfolill ap,

A ERODY AMI C C HARA C TERT S 'I ' I S OF AIRFOILS WI'I'H FLAPS J1

f-- I I H± 44

1/

--

--- - - r- - , <..... '--'::::p±;::j::::::j~ I----- + FTT 10 40

r-+- Fc lc. r I r

Vi' I- 09 36 ~ - -- - 44 f- -+-+-+-1-- ~

- r-~-J- ~

t- J2~ --- I- -I- "-

~_~, __ I-t- ~ - .:=:=f- r-:- _ . - ji _ -=_ 2.0 40 ]",0 7

-- I- -+- 1- 28 't:, 0 T - - - r-- - I-- -1- l- I- o· .t 1. 8 36 ~ f- I- f-f- I- I-' Q;' - f--- 1-1- - - ~ .06 24t % 1 - f-- - I L j 1. 6 32 q \) l..

I- - 20(j

'll 1 - . f-r- f-f-f-f-r-,-- L 1- I . - ~ g- 05

'll f- --f-

28 g> 0 ! t RN 1. 4.28 .Il! -k

H Efr

'b -r- f-c- I/ +- . . . - ..g ';' 04

-(-

16 ~

, C. p' . · 8, 160 , 000 _ /2 24 .... 'll f- l- t- 24 2 0

2 r- x !-I'-'--J,_, / /,, 3,7 8 0000 . " . 'll~

_.

~ ~I-

1-1- .... .,... 0 0.03 1 2 ~ II" I I <§ 8 20 t:o 40 f-_ ~ DI/r---- c .I P ":'t--:., I /.O . ~ . 20 ~ d: a' o ~ - " '. '\ Id' r1--- I . u~' 02 S' !:; l.

~ ~ f- " ! ,t l i'-- I . 8~,16 cS

'--"'-

~

1- :::- g- 16'1; 60 II /l" ,, _ r-r- ~

~ E:1C d ,

roo ViJ

r- l. l.. I- rr f- 0 0 1 4.):; ~ \) \5 I 2 ~ 8 0 \ 1- .6 \) 12 1-1- f-r- V I 0 V .... II f- -f- II f -1-t-i ';:

o o;g

x

- Cl

I-r- . i!:: 8'0 1- V- I- f\ \+ --t-t-+-+ . 4-.J

'm J ',x l- I- 08

moc .:' r- /00 g

H- I - t- -4 '0

I- I- i- E -· 1 ~ 1: I- f- I ~ II I- V k' I \, (.)

1-- 1- .2 04 ~ ....:. - 2

~ 4 ~ ' f-f- li -t=~~ rf D r- I~

-S g-

-t

(() I-f- - 0 1-1- 1-1- 0

f ;1 a

i ..8 0 a.

. I- - "-~ f- i ..... 1-1- 1 - -- AirfO I l.- NA.C.A . 23012* RN., '],090000 \)-3 "

-- - Ie I -f- Size.5"x,30 " Ve/.(fi/sec.) : 70.2 Airfoil' NA.CA. 23012 with externol-a i r-" - .2 ~ Pres. (stnd otm.):20.5, Date: 8- 5 -35 <IJ

foil flop (inverted), R.N (Efn 8,160,000 j_

- -1- 16 £::-4 f- Tested- L.MA.L. Test: VD.T. 1280 Dote: 8-5-35 Test: VD . 1. 1280 l- I- - .4 -8 f- Corrected for tunnel-wall effect.

Corcecird te; in f ~ nite , aspect ~afia, ~ '-- -4 0 4 8 1 2 1 6 20 2 4 28 3 2 36 -4 ~2 0 .2 4 .6 .8 1.0 12 14 /.6 1. 8 A nqle of at ta c K, C( ( deq r ees) * W i lh exte r nal-airfo i l fl op (Inverfed) L i ft coeff i cient, FJOIlRE 1o . · 'r l le N'. A. C . A. 230 12 airfo il wit h O .20f w N. A . C. A. 23 0J 2 external-airfo il fl ap. Fl ap a ogl e, _3° (i nve rt ed). T he airfo il is t he sa me as used for va l'i able- density tunne l test 1273 (fig. 14) except in ve rted; u. c. fro m leading edge, 0 .252c; n, c. above main wing chord, - O .O ic.

I (a. c. ). I I I I I .11 I I f- f- l- t-I- I ~ I - -t- -I- 40 f- 1-1- .10 H-f- R.N £i f I .0 9 8,2 6 0.000 .

I ,.

.4 4 3,880 , 000 .

. . 08 2.0 .4 0 ij .

I- -l- . \) : .0 7

; ~ J

ll' Ql- I.S . 36 ~ , .I ~ o G;, .

~~ <u .3 2 c:s U /.6 : '~ CJ->.0 5 . ~ - ' Cl I .L 1 "'- /,4 .2 8.~ {j 28'tJ 0 Cl I .u ~. 04 <ll .;: ,$ / ,

24 ~ 20 .24 'V ~

" f' ''' '

c.p .

l! I / ~ o a , l...03 ~ a . 'l! \) - ~ .

LID " ~ '-- .20 CJ-> Q..

~ 20.'::. 40 .0:0 ~

1"-- , v.ir"

"·1 1 I

-- f- " ::2 Cl

0; ~ . 02 ~ CI l.. Cd , '-L e..- .16 cS , S~ {j 16 ~ 60 /' :--r- / \) r"-.

ti1T-

II j'..

/ V V 6 i!:: .1 2 -2 12 ::' 80 a' , V ;::: a II V- i'-- -.J r- V ./ .0 8 .4 ~ 8 ~ /OO ~ V I IV V o u f - .I , V C "' at:

1-1 1 /1

.0 4 ~ 4 ~ /2 0 . c;, t, - .- )( ~ .! - v , t-- x X - 1- ' 1- :' - . 2- ~ a.

I::::; rr

V c..---

1 t3 o

.-'

-b

o ·S1 40

, ,-

Ai rfoil.- NA.CA . 23012 *

-.3- Si ze: 5 "xJO " Vel(rt./ sec.): 69.6

_1 2

Ai rfoil- NA.CA. 23012 wilh exlernol-oir - -4 ~ Pres . (st'nd aim.): 20.8

-l

foil flop R.N (Ef f ): 8, 260,000 Te s led-L.MA.L Test: VO,T. 1281-2 f-L, 0-. 4 -16 Dole: 8-8-35 Test: lI.D. T 1281-2 Da l e: 8 -8 - 35 R.N: 3 , /3~000 !

-8

-/ -

Corrected to i nfinite aspect ratio.

Correcled for tunne l-wo ll e feet -12 -8 -4 0 4 8 /2 16 20 2 4 28 32 .2 0 .2 .4 .6 .8 /.0 /, 2 /, 4 /. 6 /.8 2.0 22 Anqle of alfack , C( (deqrees) * W dh exl erno l-ai rfo il f l op .

Lif t coef fi cie nt, c FWU Rr. l6. - ~ ' he N. A. C. A. 23012 a ir foil wit h O .2Ocw . A. C. A. 23012 externa l- airfoil fl ap, Fl ap angl e, 20°. T he airfo il is th e same as used for variable-densi ty tunnel test 1273 (fig. 14) exeept t he fl ap setting. Tbe value of fm(a,c,)o is co m p ut ed abont t he aer odynamic ce n ter as determined for test 1273 ,

J2 REPORT N A'I' IO . <\T, ADVTRORY CO MMT'lvI' EE FOR AERO A 'I'! '8

. 44 <i) J. 08 I-I-I-HH-I-++--I-HH-+---1 J2 IIJ .40 .... : f- I-I- - I- - - I- ~ 2. 0 S·07 28~ .36 ~ +-+-+-+--~~!-HHH-+-+I~ l ·1 xc 'q) . 06 r-- 1I'4 C O

.32 0 1- 17 .~-

q lJ 05 t-~HHHH ~/ 4 20. 0 ~t~' I..

.., . ~ i5 . 04 I--+--++--f--l- ,V l / ~ 1- I ~

1. 2-....· . 24 ~ ~ ,- Q.

~ ~ ~ . 03 ~ HH-+-+-+++~+-+-+-+-+-+-!-H H / 4 H-+-+~ ~ /O:~ 0 V V1 0

..::: . 20 8 I.. ~

-...: ()-. Q.. .f.Q I.l.::>o2.t::: r-. +- H-++ +- -l-I--T-++- ::J,.-+--!Q ++-HH ,- "y <:H 8' 8~/SO Y ;,!§ u' ~ ~

,... 0 I H -+-+---l--f-H-+-+ po' 4 <

6~.12 ~

0 r+~~~.-r+~~ ~~~~-4~+-~~ 0

«0 ./ -l:: .0.8 .4

V ~

.... .1 4~ 1: .2 . 04 ,'- 0 4 IIJ lJ

. .g

I..

-.: /! _ .flV V 1-_ -R '0

Q.

'" A lrfo'; NA C A. 23 0 12 " 0 0 IIJ J.....i < ~ I- " =r - "", I. · ~ ~

~

l

Y

.\; 8-1-35 Ve l. (fl/s ec.). 7 0. 0. 3 -. 3 f'-- l- l n ! ' i j -"- L -12g-

v

Siz e 5"x3 0 '; R N 3. 08 0,00 0 ' - .2 V I- L I - I-L..I .-'--:-'--c~ -~I- '" -4 :::i.

Pr es (sf'nd a im ) 20 8 ~ _ 4 Airfoil N A C A 2 3 012 w dh ex/ er nol - a i rfoil flop . -16 ;.; L. M A L Tes /: VDJ I2 78 -6 - 4 E: Do l e 8- 1 -3 5, Tesf. VOT. 12 78-6, R.N :{Eff.) 8,140 , 000 - 8 Corr ecl ed, fo r IjJnne!- w allefr . ~ Resu lf s c or r eC/c d /0 mfmife aspect ra tio.

- 12 - 8 -4 0. 4 8 12 16 20 24 o. ~ .4 -.6 .8 /.0 1.2 1. 4 16 /.8 2.0 22 Ang le o f o /to c k, a (degr e es) - W ith e .-..l er nal - olrfo'; flap. Lift coeffici ent , C, Fl OU IlE 17 .- Th e N . A . . A . 23012 a irfoil with 0 . 2Oc ~ N . A . C. A . 23 01 2 eX L ernal-airfoil !l ap. Fl a p angl e, 30° . The airfo il is th e sa me as used for variabl e· density l unnel tes L L 2i a (fig. 1' 1) excep t th e n ap se tting. 1' he \'alue of CM(U . c.lo is co mput ed ab out th e ae rod ynamic ~-c nter as determined for test 1 273 .

(a .c .) o . 11

1ft - ~-.j

I 1- 1-1- I-f- 1-,- f-- - ,--

I- -f- -- -i- . 10 - lI' 40

11 - -

-

c- /

f-+--l-+-+-t -+-1- ---l

J J :- -i- - --l---'f-+ - -- H--±c77"-=-""""--'--' / .44 .0 9 ./ _ £ ff. R N. !-!- i +-+-+-H - it -c- V f--- --+-- - 8,34 0,0 00. ~ : 20 40 <.> 3,840, 000 - ~ - . ' c: V f-I-I- 1- I I :q l!- 1-1-- 1 .836 :~ .07 1-

1- - - - -t Ic" -t;; Y" j-\~ ~ t - I- ~

Q) I . - t-j--.. , /- j}\'N,'\ 1. 6 . 32 ~ -t- .0.6 II t-t-

~ i if +-+- 11 1 '\ <J lJ

1 1 .0. 5

28 Q) 0. I j I- ~ ~ /' 1 4. 28 ~- ~

I- t- - t- -l-

q4

24f2D - 1 ~ V t-= / ' -l t- ~~ . 24~1

I t- -r-

-r

Cd,

20 ~ 40 1 i I-I- I ,& . -; t-- Wf20 ~ ~

-.- 03 t- j,;> ~ t: t- t- t;::t;:; W' I-j:::: Q . ()-.o..: \- t;:;; , - t- I-

~ 16 ~ 60 t-1- Ct VjL ~ 1",v f- 1-1- - .8~ . /6 ~ .0.2 t-

V

-1-

~ ~ H- 'V l/V V 1- I-t- ~ C)

.0.1 j-- --

V- r-- r-- r-

i5 I 2 ~ 8D f-t-1- I V l V 1- . 1-1- .6 ~ .12

t7

- - t- t- f-

-C: ~ I f..' ..... t r ~ 7 > 'J) ~ -

« 0

~ 8 ~ 100 ~ v- ~ ,. , 1- 4 ~ _ 08

'"

-"

~ 0 r-I- ~ it0 1 ~ V t- f-

'" U '" i- I :

f-. I \-

t-

'0 4 SI20 ~ C D L_ t-" 1'---.2 . 04 Co)

, V- ! -1-1- f- . 1 -;[" 1:-: u V II I r-"" I '--='O - ~ . f-;- k -

~ 01.. 1 40 t o. ~ -T

l

o Q) rut I AIr . fo il N. A. C A. 2 3 0 /2 w it h J

'l:: Q. f exte r n al,o l T- f o ll flap.

J

- 4<:;, 1 60. Sl z e: 5" x 3D" Ve l (ri /s ec .) : 68 4 -. F' : :+ a

~rr* I ~'mt~l -

~ Pr es. (s tnd aim .): 21.3 .

Ai rfo Il NA .C A. 230 /2 w tlh ex l ernol-OIrfot! I i,:;; - 8 <..i T e sledL MA .L. T e st . VOT. 1 282- 3 J- A] -16 Test: VO .T. 12 82-3 R N : {Eff} 8.31 0.0 00

Oale : 8-10-3 5 RN·3ISO,OOO l

If Results correc led 10 Infinite asp ec t r o llo .

~, _ Corrected for lunnel- wp/I effect '-"- -1 6 -1 2 -8 -4 0 4 8 12 16 20 C4 28 32 -2 0. .2 .4 6 .8 !O 1.2 14 /.6 1.8 2.0 Angle of olfoc/<., « (d egrees) Lift coefficient. c, F IOU K,: I S. - Th e . A. C . A . 23 01 2 ai rf o il w ith O.2 Ocw . A . C . A . 23 0 12 exlernal -a irfo il fl ap. I' lap angle. 40° . '1 ' ho airfoil is the same as u se d for variahle·densily tuon e ll esl 1273 (rlg, H ) exce pt the fl ap se llin g. Tb e va lli e of r .. ( " . c.) o is co mpllted aho ut I he nerod yna m i(' center as determined for t es t 1 273.

AERODY J MI C CHARA TERISTICS OF IRFOIL WITH F L AP c- o .c.

.11

v i-

I: i- r-:::: i-

==-

. /0 40

r

~ f- I-f- .44 . 09 36 ~

J

~ 2.0 .40 ....,.08 32~ c: "'- .cu I. B . 36 .g.07 28 'is EffRN .Q' 8. 180. 0 00 "'" /. 6 . 32 ~ .06 24 Ci 3,350 , 000 / tJ U '- ~ : 1/ -I- -

/.4 .2 8 t ~.05 20t

b\;. .

II QJ

. Il! il

(\ , I"<-... ....

·c .p.

J

"-

- , l?cf24Jl. ~ . 04 16 ~ f.:.-.

'-k

'" ,- 't o 'Q; ~

t---

v· i:1

20 12~

1.0 <\J . 8 l.. .0 3

l- I C a' , L I ~

: \2 (» 0.. ~ "

I/ L/.D V

.w S

.8~ .I S ~ .02 8 ,....

V II l..

() Cj Cdo~" i'-- ~ 17 u ~ .6 . 12 .01 4 ~ V 1 7 I <:::: 1 " u

II x x x L..< , . .1 x x

.4-..J . OB 0 O:{g . C

r

1 \ ma tl K 1 ./ 1 V .2 . 04

,j' - I 4'0

,.y V C D II i'"-t- ~ o 0

't - .2

8'" c: If () Airfoil.' NA. C.A. 23021 with exferno/- I u II airfoi l flop 1 RN:.3,IOO . OOO

"

-.2 - 1 2 ~ - 3 Size: S"x 30 ' Vel. (ft./sec.) : 69.7 Airfoil.' NA.C.A. 23021 with external-a i r- Pr es.(st'ndalm.):20 .B, Dole: 7-22-35 foil flap R .N (Effi: 8.180,000 - .4 -8 ~ - .4 - 16 Tested' L.M.A.L. Test: V.D . T. 1274 Dot e: 7 -22 -35 Test: V.OJ 127 4 ~ Corrected for tunnel- wall effect.

Correcfed to infinite aspect ralio.

- {3 - 4 0 4 B 1 2 16 20 24 2B 32 -:4 -. 2 0 .2 .4 .6 .8 1.0 /2 /,4 1.6 /.8 Angle of alla cl< . a' (degrees) Lif! coefficient , C , FI " 1l " "gl c _________ . _________ ____________________________ _____ ____ _3 0 Ph' oi be low m ai n wing chor cl __ ~___ _____ ___ _____ O.054 clII U.(H [)(' l\ l a in win g 8ccLioll __________________________________ .. _. ___ N .. \ . C . A. 23021 Piv o t a ft lI a p l ead in g edge ___________________ . 24e/ .040 (' F l ap scctioD ______________________________ . _______________ N .. 1 . ( '. A. 2aO I ~ Pi vo t be lo\\' fl a p c ho 1'd _____________ . _ __ ____ . 10c/ . 0167 (' ~ \ 1 8i n wing cho rd , t'u__ _ _____________________________________ O. 8 :j:3c Fla p displacement angIe ________ ________ __ _:30 Fl ap Chor d, c/= 0 .20 " ____________________ . __________________________ . 1667c fl, c. rr om l ead in ' e dg e. ____ . ________________________ • _____________ _ . 2'l9c D atum cho rd , c=c",+Cj (I , (:. above main wing chord ________ . _________ " ___ ._______ _ ____ ._ .OG e Pi vot a ft trai lin g e dge of C ____________________________ ____ O. 03c . . 026e w }' IO U J<E J O. - Tb c . A. C. A. 2302 1 a irf oi l lIni. il 0.10 c 1 •• \. C .. \ . 23312 external- a irfoi l fl ap .

m a .c.

I-I- I- . 1 I - - 44 1 ...- r- I ",b, :

I-e-

i'--..

I .44 09 J6~ <\J

J

32 ~ c: QJ . III I.B .36 ~ . 07 28~ ~ -.:: Eff. RN ~ ~ 1.6 . 32 ~ .06 - 24 0- 8.2 00.000 <\J tJ U 3, 820,000 , "

'B

28 ~ 0 , 1.4 28 "f. g-.o.5

-r

20 I...

/ T .....

f- f-f- -f- CO f-H ~il c. p. u l ~ 24 () 20 -f- !

- - - ~ . 1= . 12(f24~ ~ . 04 f- /6 QJ H .!!!

I- 'F -c.

~ ;.; ~ I- I-I- l- I- I-f-

l>r ~ 10 ~ 1-1- l- I- l-

v~ It' -

17 Ll O

If II ~

~ZO 1: 4 0 I- l- I-

1.0 ~ .20 8 2 . 03

12 ~ ~ 0 a' o I-I- V 1 - l- V I;'~ J>..- I- V ~ :\2 (» 0..

. ~ 1'-.. 1-

II

I- 1-1- f-

g- 1 6'1; 60 ~ . 16 tl 0.2 l-

8~

ll'. • 1» '- .

V C d, J.....- l- I- '- <... - () Q ·S Gil/' P u V I I- l..

'6 12 J. 80

.6 12 .01 Q'

/ r:I 4~

-2 u 1 ...-- <:::: " D <;::: '" .4-..J

:.:, 8 ::' 10 0 o

1· - CD 1 "- ' I- f- H -

h- ' i- O~

f- ' .,.,. .

'.-

"- c: .; :;::: V V c : I o 4 ~ moe .2 . 04

rJ -. I 4 tl

Y . / :g \.

p- "-

- p ~

()

~ 0 ~ 't -Z

-{3 ~ A ir fo il: N A .C. A. 23021 with e xternal- o .!; tl'I U airfoil flap (t'nverle dJR .N :.3,IIO,OOO c:

f- f- -

-4 ~ -.2 ..... - .3 1 2" Size : S"x30." Vel. (f l./sec .): 69.S f- I- A Ir foil- NA .C. A. 2302/ with external-air- ~ ~ Pres.(stndalm.):2o.9. Do le : 7-29 - 35 l- I- f- foil flap (tr7Verled). R. N:( Eff ) 8,200,00.0 - 8 l- I- -I- -.4 ~-4 Tesled·L.M.A.L. Test: V.D.T. 1277 - 1 6 Dote: 7-23-3 5 Te s t : V.D.T. 1277 f-.

l- - l- I- I- Correeled for funnel-wall effect. ~ Correc te d 10 infinit e aspect raf io.

-{3 -4 0 4 8 /2 16 20 24 28 32 -.4 -:2 0 .2 .4 .6 .8 1.0 /,2 1. 4 /. 6 /.8 Angle of allack. a' (deorees) L iff coefficient, c , FIGURE ZO.-The N . A . C. A . 23021 air f oi l with 0.2Oc . . A . C. A. 230 12 "xte rn a l ·a ir[oil 1Iap. Flap an gle, -: 3 (i n verted ), The a irfoil is tho sa me as u se d [ or variable- dOD s ity tunuel t t 1274 (Og. 19) except iuverte<l ; a. c. fr om l eading edgo, 0.2 17 .:; u. e. II bovo m a iu wing cho rd, -O.Ol e.

14 REPOR' I ' A'l'lONAL ADVISOH ,Y CO MMIT ' l'EE FOR AERO AUT I

Thc 1ll1l111llUJH dra g coe ffi c ient obtained for bo th c ur ves how the effect of sea le on Ut C chn rncLel'islic s a irroil-Hap co mbin a tion indi c at a ligh t favorable plotted . 1t will be not ed that the cule-cfr ecL curY(' for interfcrcn ce b et ween the airfoil and the fl ap. Th e th e maximum lif t coe ffi cien t of th J ,C, A, 23 01 2 \'DIliC obt ain ed at an e fl' ect iy e R eyno ld s Numb er of a irf oiI-fhlp c ombination a d eterm in ed in th c v,n iabl e- a bout 8,000,000 we re 0.0069 an d 0.0097 , re p ect ivel y, den i ty wind tu nnel h as a di co ntinui ty at nil cfr C'ctivC' 1'01' t he co mbination ll S ll1"" t he N. A. C. A . 23012 and R ey nold J umb e l' of about 1,700,000. T I l(' poin L (hc N. A. C . A. 23021 f1irfoils for t hc main airfoil ec- obtained in the 7- by .LO-Joo t wind t unnel HL a n errc('- (io ll s. Thc sc \ 'a lu es are low er than tho e obtained for ti \ 'e R ey nold JumbC'l' of on l)" 1,000,000, 11 0 \\"C'\ ' C'1', Ihc T. A. C. A. 23012 and th e N. A . C. A. 23021 c- lies on the exten i on of the c ur ve obtained in Ut C' lioll ' nlollc , which h ave minimum dn g coe ffi cien t of va l' ia ble-dcn s ity wind t u nnel fl t hi gh er Reyn old I WII- n.007 1 lind 0.0101, resp ectiv ely ( refer en ce ] 0), Air- bel'S. Onl y two poi n t wer e o b ta in C'd for the com hin a- foil ' of the N. A, C, A. 230 eries of lower t hi ckn e tion u in g t he N. A. . A, 23021 ect i on for the m a i1l ra t ios ha \'in~ L h e sa m e mflxil1lul1l t hi ckness for t he ai rf o il in th e \' Hl'iahl e-den i ty t unnel , but [01' lhi s s allie ('hore\. 1I S the combinat i on tcsted <1fl'ord, h owe \" er , CH se a Iso i t app ar that a inu l ar di conti nui ty JIIil y

l l=r r T '1 ~ tJ . I 1 - -,- -;= 44

. _ ~ _ ~ -+ ( ac .~ ~ __ +_

h- --;- -r-l ::I:...1 1 .10 40

I, ,. - ~ -,----,- -- -'--- V;- I _ Efr RN .d _ j 09 36 <U 1 - I 8 060. 000 y ', -r -r- . (l) -j - --+- ' , -t / 1 : / --1- 44 {f - , - - ~ , - j j , 3~ + 770,OOO j( .-t- ~ --r- "'. . 08 32 v'

L l ~: L - ~ ; I- 2. 0 40 ~ r- I ~

. - - , /- .1, -: , 07 r-- "8,., ° I

j

I r. >' Ilc,..~ ':! . L " ~ r-r~ I . ~ -J--+- ~ -'- h'-ri ' / ~ '8 .36 ~06 . -+ - t ' - --~ .

"8 ~ 0 .... 1: I 1 ~ c;~ tA -t f- J '\ :: '232 8~ ~.05 -== :~-1 - I ::- -- b1

:4]20 Ji~ ! , :A i y ~ l~ : ~ 24}~0 4 _-== -= T c_t -= ~~ ~ I 1

~20 ~ 4o Hl,l i l ~ }~~ L e- ~r- ~ } d 0 ! r~~ ___ e" o- -i L :c~ U - =~ ::- ~~

8' 16:;;- 60 ; -+ L { O I ~ I" +-- . ,- A ± - .8 ~ .16 \) --- ,/ ,d - ~

i3 ~ 't-t-- ;< 1 1- t \J 6 .01 +- 4

~ /2'S 80 I / ~ ) ; r ~ H-" II I .63 O H- f- I- -.- ... _ .. J ..... ..u -- o~

~ 8 '0/ , ~ 1--+C . __ Ai -j y~ ,.....;--.., r--, 4 08 - ,x-y ......... :-::::- r f- -1-- 0

,,-"t ~ J-. I f- f- -f- f-- ;;' --4 '--1 4 '0

o 4 ~ 12 0 ./ ~ I '-I- -t " - . [)4 ..t - f--:: ;..; ---t ~

.0 '- "' 1 ' ~ 1 -t" I- rl f- 1 -, -f-f- r- - 1 i 0 ~ • (}>

~ 0 Q r I ~-L,-- ~l ti ' ~ x i- ;, ~ I 0 ' ~ ~~ . ~'=- T - T"'+r X - - T -"" " T :,:: x r:: ~ " k> ~

..... V- Airf,:,,"/: NA , C. A. 23 'CI , with exter'hol v .. _ ~ r I

.S \ 1 O lrfot! flap:, Velocily(fl/sec} : 70.2 I: _ J - - Ll' I L I I I -

-4· ,- Size : 5 x30 R.N.3,050,OOO - .2 <!> .---'-C --'-'--:-+: I

~ IH-+--+-t-Il f--'-....,Pres.(sf'nda lm.): 20.8 Dale : 8-3-35 t-:4 A Ir fo il: NAC.A. 23021 wit h ex t e rnal-alrfoi/ flop. -/6 -8 1 I Tesfed.LM.A.L. Tes l : V.0.T.l279 -.4 ~ _ Dafe:8 - 3-35 , Tes!. VD.T 127:3, R.N , ·(Ef!} 8 ,0 6 0,000 I '- I I Corr(!cfed for lunne,l - wal/effer;/. "[ Re su lfs correcfed /0 infinite aspect ra t io .

-12 -8 -4 0 4 8 12 16 20 24 28 32 -:2 0 .2 .4 .6 .8 1.0 1.2 1. 4 1.6 18 20 22 24

Angle of olfack. C( (degrees) L dt coe ffi cie nt, C , "'f(; I' /<JC ~I. - The X . . \ . C. A. 23021 air foil wilh O . 20c ~ N. _ \. C .. \ . 230 12 eXlcmHI·airfoil fl ap . Flap an~ l e, 30°. The a irfoil is th e sa me as u se d f or \'ll riuhlc-ucl1, il y lUllltcllc.. <.;L 1 271 ( fil! . 19 ) e\ccpt the Onp s etting . The \ -n !ucor c"'( .rJ i~ (;ompuled aho ut the aerodynamic center as determined ror t ~ t 1271.

t1 u II \' ('( . (.('1' cO lllparison . On e uch cct i on is t l lC' I . A . exi st, H S cv id enced by th e low maxillllll1l lift coer fi ci (' nL ( '. A. 2:30 10 pr ec li cte d to lwvC' n minimwn dra g eod - ob ta in ed at an C' n' ect i ve R ey nolds Number of .3, 00,000 , rieiclil of 0.0067 Hnd anot h c r i t lt e N. A. C. A . 230 1 , An ex pln n ation of tbi phC'lloJ1lcnon a n cl the ,Ippnr- w l tidl ha s <I minimum dra g co err-iciell t of 0.0091 (r d- e li L difl'erell e be tween th e rcs ult · from the two tun- erencc 10 ), The se va lue s fll'e ligh t ly lowcr t1wn nels i indi cate d by t he fact that the obsc n - ed eli <.:0 11 - (hosC' obtflL II C'cl with the c omparable wing-flnp co m- tin lIi ty tC' nd to n pp en r at fI co n ta n t yalLl of h e te L bina tion . Re y nold T um be l' I' ll th er th an of th e e n'e eL i ve R ey n - Th e va rin t ion of maxill1umlift and minimu m dra g old, Nlimber. As point ed o ut in rcfe l' C' nce ,the coC'ffteient wit h e fl 'cctive Re y nold s N umb er ar e sh own c onccpt of en 'cct iv e Reynold s I umber i app licable in figure 22 . Th e cl a tfl plotted i.n t hi s fi gure are not on Iy wh en th e cale en 'ect is d ete rmin ed mainl y by lhe co rrc ct cd fol' lun ge ta res or for t hc crr ects of re ct an g u- inflll en ce of tlte t l'an si Lion fl'ol11 a la min ar to a t Ul'hlllcn( lar tip be cH u e t hC' e corl' ect ions were not known with bo undar y la yC'l'. In th C' pre C'nt ca e th e I1 0w thl'o ug ll (' er tH i.n t)" 11 t all nllue s of thc e fre ct iy e R ey no ld s th e s lot probn bl y is th c impor ta n t facto l' and depends N umhC' 1' . The vn l uC' s p l otted diA' er, ther efore , from upon th e boundal'y - Ia ye l' th ic kne re l ative to th e l ot the fu lly co rr ect C'(\ va lu C' , o- iy en else wh ere , but the izc, which in tllrn i more nearly l ependent on the AERODY r AMIC C HARA CTER ISTI S OF AIRFOILS WITH FLAP lC'sL I{ cy nold N um bel' L lI an on th e e il' ect ivc R eynolds cient th r oughout the hi gh- l ift ran ge, provicleu Li la l the Nu mber. Inte rpr eted on t hi ba i , the apparent con- flap i et at the propel' angle, than do plit flap . If fli ct betw een tbe re ult s obtained in the variable -d e n- a lar ge drag at a high lif t coe ffi ci ent i de ir ed to obtai n sity and the 7- by 10-foot wind tLLDne ls di appea l' , ::iteep g lidin g abi li ty, ch aracteri tics approachi ng t ll 0S (, ;l nd it is probab le that wing in fli o- h t will h ow th dis- of the s plit fl ap can be obtained by def lecti ng tlie co n ti nu ity, if at a ll , at va lu e of th e Reynold umbel' xternal -airfo il flap to lar ger nngle t h an the optim .ulll , lowc r than the effecti ve va lu e at which th e di on tinui - thu ca ll ing th e fla p to tall anel to g ive large in cr en w tics 0 cur in the var ia ble-den i ty tunne l.

of p rofile drag. A el ifl' eront hin ge ax is, el ected wit ll The ca le effect on minimum proftle drag, a bown this c haracteri tie in mind, sh ould g ive larg e availab le in 6gure 22, i about the arne fo r both co mbination.

vnlue of profile drag at hio-h lift coeffici ents wit ll u L Flap loads .- Th e var i at i on o[ fl ap normal force, flap enta iling much in c rea c in the min i mum ynille of ch ord fo rce, ::md fl ap center of pr e ure, with lift p rofile drag obta in ab le t hr oughout the lift ran ge.

coefficient o[ the airfoil -fl n,p combi n at i on is s hown in Anot her feature of exte rn al- nidoil flap i the poss i- figu re 23. Th ese data are in no ca e exte nd ed to th e bi li ty of defl ect i no- th em as ni l ero11 , while they cove l' maximum lift coefficie nt l' t he com bin at i on at the fl ap the full spa n of th e win o- a a high-lift c1evice. As a ngle in que tion on accoun t of er rat ic po in ts obta in ed expl ained in reference 1, di adva n tages in onnect io n iu the te ' t. T he data indi cated th at, with th e flap with overbalance wben t ll e aileron are def l ected difi 'e r- Rup porCo I sepa rately , ei ther the main airfoil 01' t he n ap cntinlly nncl "-lth Ln'ge values of a lv erse ~ ' n\\'in g had a tendency to sta Jl prematu rely, rendering the v 'tItle, 2.4 ill the regi on of eL m.r incon i stent and unreliable.

1 1.- Thc yariation of flap hin ge- moment oefficien t C ll i - - f-

/

... r-

l

with n ap a ngle abou t the two hinge-axi l ocations 11 ed ?

2 .0

-

1"-- r + is shown in fio-lITe 24 and 25. It will be noted that t he c 4'max p-' flap i sligh tly overba l anced between angles of _ 5° / ~ I--

i I

t

}l ,nd - 10° wh en hing ed at a:\-l l. Al t hou gh t Il e O\'e r- 1.6 10- L _ -

ba la n ce does n ot occll r in the normal fl ap - operat in g f i

j nU1ge (_ 3° t 30°), i t seoms lik ely that overba ]ull ee

.I . II

VD. T.-7 ·x 10' 1.2 03 mig ht OCttil' in operat i on of the H aps ,1 ailerons wi th NA IC.AI 230/2 wifh flop x ° .. ..

it neutral ett ing of - 3°. F or this r ea on th e eeond I-----t--N. A.C.A. 23021 + \ i---- I -I- I-f- l ociLL ion, Hxis 2 (fig. 1), wa el ecte 1 an du ed for furt ll C'l' .8 02 --- - hill gr- Ill ome ll t te t. Thi hinge axis is eXHet ly 1 - pe reeut oJ t ll e fl ap ch ord a ll ea 1 of axis 1. Even witli D

c • m ,"

- ...

tlli :1 xi , oille sli ght degre of ove rb alance rema in s .4 I-- nlth ough it is co nsiderably Ie t. h an th at enco un tered wit li axis 1 a nd is not eonsidered likely to cal .! e ailero ll

o

overbalance in t Il e hi g h- s peed condi tion.

.2 4.6 .8 1 2 4 6 8 10 Eff ective Reyno lds Number in million s 'in c t il e te t in th e va ri ab le -d ensi ty tu nn el WC'l'C' bflsed on the results of the 7- by J O-foot win d-t UJln d 1 "I OlH " ; 22. -8 c810 effoct 011 N. A . . A. 2:1 01 2 and N . A. . A. 2302l airfoils II il " O .ZOe. N. A. C. A. 23 012 external -a irloil flap . All "alue s ull c() rr edcd lor hin ge lests, it was con id ered cle si rable to use fl ap hin ge axi .- tares aud lor e ff ects 01 rcetan~ular lip~ .

2, \\ 'hich seem s lightly more SH t is factor y t h an 1, ill lhe \'flriab le-den i ty-tu nn el tests. Inn silluch as lhe lIloment rcnder t he ir va lu e as <l I II lc'I'<l I- co n tl'o l :lIT;lIlgC' - r1 HP \\' <1 llinged at nx is l for the 7- hy lO-foot willd- Ill ellt doubtrul. lllfol'LunaLely l he usC' or lhe full-spa n lunl1E'1 Le ts, there is a sligb t c1i ~('I'e panc y of fl ap po siti on f1 np 1'01' glid e co n t l' ol ,:l u gge·te c! previou l .v, is ill - hel ween L ll e final fo rce te ts in t Il e two tl illn eis. Th C' compntib le with it use ;I S a l ateral - contro l device . A li rat e of variation of lift a nd d rag ch aracter i ties with ,HJ'nngelll en t usin g t he tip portion s a co m bi n ed ll ilc- fl ap position, as hown in figu re 4, in li eate , h o we ve r, rons and flap, wit h tl lC cente r po r ti on ca pable of be ill g t hn.t the effe ct of this din'ereMe on th e final force -te st def lected to mueh l arger angle fo r gli de ontro l, dala ))lay be re ga rded as n egligibl e.

nppea r to oner a po ibili ty of co mbinin g the e vn ri li S General features of eombinations of airfoil and fea tU l' e , provi l eel t ll a t tho lar ge va lues 0[' adv'1' Rc external-airfoil flap.- The pre 'e nt exLernal-air foi l fl ap yawing moment are a eptab l e.

combination appeal' to hav e a many de irabl e ae1'O - With the clatfl available at pr e ent, it is po s ible to uynamic c hara cter i tics as ot l lCr good hi g h-lift device determine the relative J1l I'it of the lark Y an 1 the Le ' ted up to the present. Th ey give a high maximum I. A. C. A. 23012 a irf oi l ect ions for use a exte l'L1al- lin coeffici ent and a low mi nim um drao- coefficient; in n id oil fl ap on the I. A. C. A. 23012 main airJoil.

lll ese respect, howev er, th eir m e rit i appro:\-lmatcly Compa ri son of tb e re liltS in thi report with tho e or e(jlmi Lo that of Sl l Ch a dev ice a tho sp l it 11ap. At t ll reference I in li ca te. L h nL the comb in at ion with L he sa me time they g ive a mll '. 11 low I.' "n lll e of dra g coe ffi - N . A. C. A . 230 '12 fl ap ll a apl) l' cciably lower dra g

16 REPORT J ATIONAL ADVIS OH .Y C OMMITTEE FOR . \ERO I A TI CS

.004

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" +--- 0 , ~

~~ ' deLees

o 10 +- -- -3 C) '

I· x· - · - · 15

o 0 20

~ . 002 I I /r ••••• _-- 30 ..E t----=- r-:- 4 ~ CJ> . ~ I 1-- 1--- ~ 0~~~-4~~~~-~-4--~- +- -~ o _ .....

- ~ -+ -

+ 'tl Q) - --- [ ,... - - - - - --6 ~ -Q 1"- .

.... - . 002 "P . ~ .........

.~ --- ' 0

i- ."

:;::

T

<iJ - 1 1- 60 - +

2 - .0 04 -

I-

....

t: ~ <iJ E:

I ir-

o

I

i ~ -.006 --+---1- Q)

T

CJ> 'i-. " .40 . ~ I . ~ :i: UJ'£k V fl a p on N.A .c .i .

.ll

e

• ...0- ""'.

-'

~ -.008 uC l airf°r l (r T ere r I I

~1

Q) o Jo ~: - + t---r

--

II 0

-

.0" - - --. - -6 __

cr -

- -M 0 ~ ~ 60

Q) --- - - .0.- --

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e

1--- . - - t-- t- -- - I-- ~ Fi<.. t: HE 21. - l lin g e·mO lll cnL ('()l'I lil'ient s of flllp . H inge IIxis L . '- .. \ . ( ' . A. 2 :) 012 a -b .irCoil ,,' ith O.~ . s . . \. C. A. 23012 externa l· airf o il U>lp.

l -.40

I

o -I

I

~ . 002 1---1----1

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! C)' /.60 -t-- I--

~ 0>-----

CJ> O l---;--~ , 1H~ .",-+___ -+-+.::x~· - - ' - -I . c...:.: ::....----1 q i

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- -.- .

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~ - ~ -.004 Q) ....

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t- J E: - ~ r ~ -.006 f- + / l.

o ~ ....- E:

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, Q) 1--- + I CJ>

- -

-- ~ -.008

I

.4 .8 /.2 1.6 2.0 -2 0 o Lift coeffic i en~ C L FI Gt' Ul!: 1 3. \ 'ar ia li o l1 of ai r i oa d :-; on fl op with win ~ lift cocOiciclI1. N .. \ . C ... \ .

Fl t ; L" H~ 2. >, Ll iugc-IlIQIIICll l coclli cic n ts of nu p. I Lin ge ax is :1 . i':. ~ \ . C . A . ~~ 012 ~3 01~ airfoil wilh (I . ~>()c " :-I . . \. C . A. 2:3 012 e xternal· a irfoil Unp.

a irfoil wilh 0. 20<: . N . A. C '. A. 23 012 e xt e rnal·airfoil fl up.

AERODYNA U C HARA TElUSTICS OF AIRFOILS WITH .FLAP in fi gu re 26 and 27 . Th e polnr Cll eves for L be fl <LP t hr oughout the whole lift rang. Th e va lues obtain d co mbin at i ons are e nv elope Cllrve of tbe en e of in Lhe 7- by 10-f oot wind tunnel of th e speed -r ano'e po l ar obta in ed at th e va I' ious flap - anO' le ett in g", index O L j eD., which may be con icl e red repr - max m.1.1~ t hu o' iving at each Ef t co fTi cient th e minim 1.1 III profile- ' l' n tative of th e relative merit I th e two arl'an O' m en ts, dracr coe ffi cien t obtni nabl e from th e a id oi l-nap COIll- are 192 for th e J . A . C. A. 230 12 nap on th e N. A. C. A.

b il1 ,\t io n. Th e cnvel ope cu r ve for t he plit-f111P CO I\1 - 2;30 12 airfoil and 174 for t he lark Y (l ap on th e N . A.

binn tion \\ 'c l' e co n tru cLeci fr O Ill data obta in ed fl'olll C. A . 23012 air foil. Althougll Lbe co mbination with rc!'erence 11 and [rom unpubli shed te t in the va riab le - Ll1c ' la rk Y fl ap give a ligh tly hi. gh er mnximulll li.f L den s ity tun ll el. In t,h e case of the plnin a irf oi l equip ped coeffic ient, it i apparent from the yaille of t Il e specd - \\ 'itll a plit fl ap, no rcdu ct ion of p rof il e-drag coc rri eic n L range index th<tt the genera l max i mum li ft and mini- is obtained by de f! cti no' the nllp except a E[L coeffi- m um d rag c haracteri tic of th e co mbination wit ll t il

I I I I I I I I I

J J J I . I.r I I I

. 20 I-- NA .C. A. 23021 airfoil and NA .C. A. } -

I-- NA .C. A 23012 airroil and NA.CA.} ~~I

.20 2.3012 external-air-roil Tlap 2.3012 ext e rnal - airfoil flop ---; i- I- c u m• • / CJ'~I" = 249 - Cl../ftU / Cd Onoin = .344 : I , NA.C.A. 23018 air fo il ---- I ----- , NA .e.A. 23 010 airroil I -- -------- ---- ---- ./ 8 I- and sp lit flop I- .18 and split flop I I C" ~ .. I Cdom,n = e90 C L~ •• I Cd .~i" = 332 . - I - - -

- +-

I I I ./6 .16 I I 1-1- I I I I J . 14

/ 1-

I .....

I I I ./- I- I

.~

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is · I

I , I I ~ I .;:: , 1.

Q OB I

it·

I I I c: I I ~ I I I / ~ . 06 I Cr) I I

; /

/

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I /

/

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V

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y l V

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ts

i===-- ~ ~

l- I

i- 1 I i ,

T

o .B 1.2 /.6 2.0 2.4 4 2.4 o 4 .8 1.2 /.6 2.0 Section lift coefficien t, c, Section lift coerficient, c , 1 ,'lGL'n .; ~7. COIII ]) flriso ll of N .• \ . C . •\ . 2302 1 a irf oi l a nd O.20c • A . ( '. A . ~:J OI~ w 1 ,' I GURF: 26.-Co lllpa ri so n of N. ,\ . C. A. 230 12 ~i rfoi l a nd O.20e . N. A . C. A. nO I ~ cxtcrnnl- ui rr oi l Oap with N .. \ . C .. \ . 23018 air( oi l anu O.20CIO split (h lp. EfrrCLivc ex lermll ·a irfo il fl ap with N. 11 . C. A. 230 10 ai rf oi l and O.20e . spli t fl ap. EfT ecli\'e B ey noJds N um her , 8.200,000.

I ~eynolds Number, 8,200,000.

J. A. C. A. 23012 fl a p nre more f avorab le. A st udy cien ts vc r)' ncar t he Jll;\ Xi IllUIll for t hc plnin Ilirl'o il .

of t he co n tour curve for maximum lif t <md minimum TIl e cu r ve, t ll e l' efor , Il owa lso t il e compnl'is on of t he cll'll g in this r e port and in referen ce 1 h ows th at tbe external-flap device Witll a plain wing. Si ncc L he yaria Lion of optim .um posit i on of th e flap witb fl ap ~. A . C. A. 230 12 nirfoil wit ]1 a O. 20c N. A. C. 1\ .

a n O' le i more favorabl e for obtil.inin O' a hi nge po ition 23012 extcrna l-a irfoil flap h n a J1lnximull1 L llicl, ll ess g iving low op ratinO' mom n t with ut acr i ficinO' per - equa. l Lo 10 percent of t il e over-nil ch o rd , i t icon idel'('t/ formance ch aracter i st ic in th e cnse of th e N. A . . A.

dircctly compa r ab le \\ 'it h th e K. A. C. A. 230 10 <1 irfo il 230]2 (lap than in t be case of th e Cl ark Y flap.

in t ha t wi nO' of th e e t \\ ·o type, ha\ -in o' the nme pJan A compa ri on of th e J . A. C. A . 23012 exte mal- fo rm a nd area, \\ 'ould havc tbc ame maximum chi c\.;:- a id oil Hap in com bin at i on wi th N. A. C. A. 23012 and n e . T il e ame i tru e of th e N. A . C. A. 23021 ai rf oi J . A. . A. 23021 a irf oil , with the pluin a irf oils o f witll th . A. C . A. 2:30]2 cxte rn al- ai rf oil n ap iu C Ollli arab le t hi ckness equippecl wiL h sp li t fl aps i sh own com pari 011 wi th tilC . \.. C. A. 230 1 plain airfoil.

REPORT ' j\'ATIONA L AD \'[ ORY CO l\l J\' U TTEE FOR AERONA TlCS Fr om lIl e da la n ppearing i ll figm'es 26 an I 27, the ' l ZC th at a mor c complicated lllecha ni Ce ll clr il'e \\ 'ol dd a dv H nt ages of th e exte l'n al-airfo il flap o\' c 1' ot ll e l' ty pes hc neces Hr y fo l' co nve ntional fl aps, C Ol' lain o lh c l' of hi gh-li ft flaps in ge ncra l u, e at pl'e ent ,1rc imm e cli- ty pc of flap , as, fo l' cxa mpl e, th c F owlc l' or ~ <1 P , n wy hc ;ltc 'ly npparent , Th e re 'ult s shO ll - tha t, 1' 0 1' fli gh t at cxpccted to gi vc chn l'<l cL cl'i l:'>t ics morc Il c nl'l y eO lllpnl' ll- ;l il Y lift coe (fi ci (' nt ahove n PPl'o xim at cl y 0,7 , n win g hlc wi th t llO SC o r cx Lt ' l'll}ll-Hil'f o il Jl a ps L lt;lIl do lh e lI'illl Hn cxtc J'l1HI-nid o il fl np is supel'ior eit ll er to t llO ordinal'Y or s pliL ly p , TIt s ot her Ly pes, holl'c\'c l' , (' ompnl'ablc pl ain lY i ng 0 1' to one e quipp ed with;l pliL ll ll VC cxt ril , m ec hn ni c; li co mpli cat ions i ll lha l lh C'y fin p, S in ce the ma ximllill rate of climh of m ost ail'- rcquire som e otlle l' ty pe of motio ll tha n pUl' e 1' 0La lio ll , pl n ll eR occ urs at an air s p ee d C OtT e ponding to a lif t which co ntribu Les to t be Ce l e of in sta lla tion a nd o pera- co cifi cicnt n eal' 0, 7, it i ap par ent th at the exte l'n a l- ti on of extc l'l1 al- ;l iri'oil fl aps, n il' fo il flnp h as no ad Yc l' se cf r ect on the m a ximum l' nte An unde ir ab le f eaLu re of any tra iling-edge hi gh-li fL of c1im h, p 1' oyi cl ed that o th e l' f acto r a ff ect ing th e i su e, de\'ice is the 1; I' ge negati \'e pi telling momenL tl wt iL " lI ch ns \\ -ing loa din g a nd pa n, al'e th e s am e for t he

develo ps wh en o pc ra tivc , In t hi r espect th e exte l'll al-

I,\' pe s oJ wing a IT;) ngemen t heing co mp n I' ed, I t is airfoil fl e1 pS nrc s li gh tly infe ri or at equ al va l ue of t be ful'lh er nppnl'en t t ltn t 1' 0 1' nn ail'pinn c of a g i\ "e n pO ll' e l' , maximum lift coc ffi cien t to ordin ary or pli t fl t'l ps, In wC'i g ht, win g area, spl 1n , nn d ge neral " clennnes " the addi tio n to t hc s tJ'u ct urn 1 di sa d van tages in vo l vcd, tho ('xte l'n a l- ;lirf oi l fl ap ma y g i\ " C' nppl' ec iu hl e impl'oYement pl' ohl em of oh ta ining st1 (i s fn ctory bala nce a nd Lah ili ty ( )\ 'e l' th C' p hin win g in such, perfo rm ance fent ur es as hC' co me m o l' nC lit c heca use of thi c it al'Hcte l'i sli c, (a ke -o fl' , angle of ch mh, ceiling, I'nn go, endul'nn ce, a nd Th ese fetl t ures nrc some Wht lt co mp ensa Le d hy L it c llliniJll U lll r ate of descen t, a ll of which mt W inyoll-e 1' el at inl y lllall wnk e, indi cated by th e JO II ' drag, Uta I fli g hl at li ft coe ffi e- ients in excess of 0, 7, Tllis J eat ul' c occ urs when th e de fl cction of the exte rn al-airfoil na ps ma y he pa rtic ul n rl y lI se fu l in i ncreasing tl lO single- is l es t hnn t il e de fl ecL ion gil'in g the maxim um li fL eng in e ceiling of lllui tieng in e aircr aft a nd in permi t tin g coe ffi cient , Th e r e du ct ion of ta il e fl' ect ive nes d ue "uch ;li l' plan es to ma in tain fli gh t at lo\\'or s peeds, in to th e low- peed wak o, a nd in c id enta lly th e Le nden cy tnkin g o f\' fo l' C'xa mple , titan would ot hC'l'wi sc he to Lail hufl' et ing, sh oliid th ereforc bo co nsidc J' ahly less po""ihl c I\ -itll o ne engine sto pped, thnn wi th flnp s lll nl n i T drfk de d Lo IHl' ge a ll g le s aL A I:'> fa l' ns m ,lnual o pe l' nL ion of t he Jlnp in fli ght is lllH xilllulll 11f t, ('o ll('CI'n ed, the ext Cl'n a l- airfoil fl ap , hould h C' co ns id - ' ON 'L DI G REMARI ' ('J' ;Jhl :v supe l'i o l' lo slich de\'ices a ol'dinnl')" fl ap, a nd lI nhHla li ced sp li t flap on ncco un t of t he 10 \\ - Yalu c of Fr om the dn L n o hl aine cl ill the prese ll Lill \'c"lig;J (ion, L he extemHI-airfoil fl ap in comhi nat ion \\ , ith an airfoil Ilin ge moment th at cn n he obta in ed t hr ough out th e o lH ' I' ut ing n lllgC' , I r some d eg ree of oye l'h nlnn ce m ay ap pea r s to be one of the Jl10st genem ll .I' a tisfncLory bi gh-lift d.ev ices im 'estigated. to date, Th e combina- he lolc rn ted in cases whCl' e th e fl a p arc not al so used a ail c l' o ns, co n id el'nl)ly mO l' e redu ct ion in hin ge m om ent tion te. ted o Ir er ' <"l rel at ively hi gh val lie of m aX iJll ll lll li ft coe ff LC ien t wi( 'h low p ro fil e d rag in t he high-li ft "ho llJd h C' ohtninn hJe hy moving th e flap hin ge axis nm ge, At lo \\" lil' t ocf fi cient it gives vcry n en ),l y as r:ll'lllC I' h ne k on th c flap ch o l'd \\ " i th out nn y loss of IlC'l'f O I'Ill;IIl Ce c ham ct Cl'i st ics, Co mp arison of t ll e hin gc low va lues 01 pr o fil c dra g ns H goo d plain airfoil of com- Ill O lll cn Ls oh ta ined fo l' ei th e l' of the pres en t flap llinge p .u nble t hi cl ,me ' s, St r uct u l'H l a nd stab ili Ly prob leJll s n socia ted wi th t he I Hrgr neg ali vc pi Le hing IllOlllc nl s ;l xe" Il 'i t ll t he da ta of I'eferen ce 11 indicntes t hat lhi s ;1 1'J' a ll ge lll ent of t he C'xte l'na l-airfo il f1np r equil'es ;d >o u( OCC UlTin g n t high IiJt coe ffi cient, Ill n.\' be , Ii gh ll y o ll C'- th i l'd tll e o p C' [';lling Ill O Jll ent of co mp,II'Hhlc si zc ' gr eater t han in L hc C;lse of ordin nr> ' nnd sp l iL fln ps , A o /' o l'<i i ll:l J' )' (I:lP l hJ'OlI gho ll t L he n0 1'ln l 11 mn g(', Thi s fli ght in vest ig ati o ll o /' l hi s ly po oJ de\' i cC' in sta ll ed O il a (' ;1 ,,(, o/' o pl ' l' nlioll sholiid f ;J(' ilil;JL e ;lcijll "tlll C' nt or (h(' F airchild 22 ;li rpl n ll C', \"i t h full-s pa ll fln p" <lJ' I' <l ngl'tl (0 gli(k pnlh in appJ' (l ;J (' h c" 10 a Inllding ; 111<1 pel'lllil th C' op C' I' ;l (e a lso as a il t 'J' o ll ", is HO I\ - be ing Cll nd llC'[.e d by L il e T A , C, "\, l l ~t' o /' <l diJ' ed fin p -o pe l'll L ill g !e n 'l' 0 11 niJ'plnllcs o r 1:'> 1I ch

AERODY A MI H)

HARA ' rERIS'l ' I S OF AIRFOILS WI'l'R FLAPS 6. Jacob, Ea tman ., 'W ard, K en n eth E., and Pink erton, LA GL EY 1{EMORIAL AERO NAUT I AL LABORATORY , R obert M. : The hara eiC' ri tic of 7 R e lat ed Airr o il ATIONAT. AD VI SORY COll [MJ' l'T EE F OR A E RONA ' ),.1 S, S ect ion from T e t in th e Variabl e -D ens i ty Wind Tunn e l.

i JA TG L1DY FI ELD, VA. , .l\( [aT ch ,'25, 19 6.

T . R. No . 460, . A. C. A., 1933.

7. Jac b , Ea tman N., and Clay, William C. : Charact.e ri ;;- REF ERE E tic of the N . A. C. A. 230 12 Airfoil from T c tin t.h I . Pl att, Rob e rt C. : Ae rod y n am ic Chara cte ri st ics of Win g FlIll- cale and Va r iable-D en it y Tunne ls. T . R. No.

with Cambered External-Airfoil Flap, In cluding La t. e ra I 530, . A. C. A., J 935.

Control with a Full-. I an Flap. T . R. o . 54·1, . A.

Platt, R obe r t C. : Turbul nce Factors o r N. A. C. A. \Villcl . A ., 1935.

Tunn el a D etenu in cl by ph r e T esi s. T . R . No. fifiR, 2. Il arri ., Thomas A.: Th e 7 by l 0 Foot. Wi nd Tunn e l of t.he . A. C. A., 1936 .

r ational Achisory ommit.t. ee ror Ae ronautic . T . R.

9. Ja cobs, Ea tman N., and Pink ert.on, Rob er t M .: T es [. ::; ill No. 412, . A. C. A., 193 1.

th Vari ab le -D ens it y Wino Tunn el of R e lat ed Airfoil s :1. J acobs, Eastma n 1 ., and AblJo Lt., Tnt 11. : Th e N . A. . A.

FJ aving the M ax imum Camb er nu uall y Far Forwa r d.

Variable-Densit.v Wind Tllnn I. T . R. No . 416, N. A .

T. R. N o. 537, r. A. C. A. , 1935.

. A., 1932.

10. Jacob, Ea tman ., and Pink e rton, Robert M.: Te , [. 8 or 4. W en xin ge r , arl J.: Wincl-Tunnel M eas ur e ment s of Ai r . A. C. A. Airfoi ls in the Variabl e-D ensi ty Wind TUllll r l.

r .oads on Flpl it Fl ap. T. . No. 498, r. A. . A., 1934.

• 'e ri es 230 . T . . N o . :367, . A. C. A., 1936.

ri. Pi aU, R obe rt C.: A r ody nam ic Charact.e ri st ics [ a Win g II . 'v Y nz i ngcr , Car l .T .: 'vVi nd-Tunnel Tn ves t.igat.ion of rciin 't r y wit.h F O II"l er Flap , ]n c luding Fl a p Lo a ds, Do\\'n\\' ash, a nd and Sp li t Flap , on Airfoils o[ Din·el'en!. PI·ofill '. T . R .

'altillated Effect on Tak p- Ofr. T . R . o . .')3 4, . A.

o. !i!i 4, N . A. C . A., I O:1(i.

C. A .• If) :3!'i.

--:: H ~ ~ H j ~ t'.l '=j o ~ >- t'.l ;U o Z > ~ H UJ

tv ::u t>:j ":;j o ~ Z > ,.., H o Z :> t"' > o UJ o ::u ..-: () o

o c her, per- cent Cam- .;0 .;0 strnctural a\i- . .

per- cent 10.00 10.00 10.00 10.00 10.00 Ii I, 17.50 )d mum , for -1--

I

:-- ~ ed c us li.8b ti.88 6. 6.88 0.88 12.03 12.03 -- 12.03 0.65c, be percent

I

ThiC'kne 58 51> mny .90 .

c 8.\)0 S b,90 b.90 8.90 5.

15.58 1 0. 1&, percel1l thai fi. 1'1

0~7~ Wi

n s ign : .0112 .Olbl .0342 . .00!J7 .Olg, . l = tip,:.;

C ~

lcrisiics de

charnc- I 1_

l!

und pcr ·1 ii ro

fad. U~ 4.52 4.43 3.36 4. 3. 4.62

chflrac ""iIl teri sties; ill!

J c

~~ 33 35 33 26 24 35

'mn.z / dditional (' Actual, percent a at 11111 p c

:-)

c.

Com- ?d , )luled.

per('em

,-- 1--------

rin ' I'!

IlL Dt m Iii Om 1.;7 13, I . 2:),1 20, 147 131 cd (' 'c Ii I C ---- ho\

-, -

{'Pili ,r. .\ c, per- ----- 1-- " II ., E . 0 .2 c .

Be- per- --- 23. U hind ('enl 24 25 '21.

tk " 1.. ------ :- i -- T A - QO'J lated charac \ cri::;\iesj .

O.

D_-\. -.013 -.Oll tlC"'fl.r .. uR(.'leri ----.

--

<:h n l ' tabu mi Ol'ifl QQli\! 010-1 OW OO'J dr, .0329 .

of . . .0097 .

(" ------- O.

--- RFOIL , 1 U . .5h .35 .45 <"fI 0.07 0 0 -: --- I.

1 105 072 0~3 per . .

explanation .Oh6 . .102 .IO-! .100 Funtinl11('lluil section 0.

(1 de~ree --- for

' ' \

.4 . 3 .

~. 3 TABLE 'a 9 15.5 - . 9 a -0.9 -V.U de -13.b - -1 s.

--- • onar 15 12 12 12 14 11 chord OM 13 16 L dee.

O' (; --- a a p reference - a.: lti 62 52 27 the 'm I 1. 1.0-1 2. 2.37 2.0[ 1. 1. 2.41 C [::lee -- and -. ~ ~ ;-" 16 ing \'( 26 2O i \I I mil- Iion 8.21 8. 8. S.14 8.34 8.20 h. 0.06 -- EtTec- H .

the of m " • _\ I) _\ A A A A _\ I C sunJ I

.. -- --

- - - - - -

the E.

--- ----- ----- is >i.

- - -- - - -- -- --.---- ---- th - -

-t---_ - -

- -- ---

I) - --- leng --- ------ P.

Classification

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

--,---,---

I----"r-

I

chord \ \ _ A A .\ .\ _ 11 11 ChOIr! the

--

s . 10 10 30 :30 tion

-3 -, -3 -;3

!!

ORP .

a (Ic~ :\lerllnl inverted inverted :: SCllin I airfoil

1 {

I comput

'I

se A.

A

____ ______ the C.

\ . c.

A. In Airfoil 23012 23021.

• :\. _ :\.

,-

~ I

r

~.-----.

Z Positive directions of axes and angles (forces and moments) are shown by arrows Angle Velocitiel Axis Moment about axis Force (parallel Linear to axis) (compo- Sym- Sym- Positive Designa- Sym- Angular Designation symbol Designation nentalong bol bol direction tion bol axis) Rolling _____ RoIL ____ LongitudinaL __ u p X X L Y----.Z Pi tch ____ LateraL _______ Pitching ____ II q M Z----.X 8 Y Y yawing ____ _ ya w __ _ __

'"

N ormaL ___ - ___ w r Z Z N X----.Y if!

Angle of set of control sUl'face (relative to neutral Absolute coefficients of moment positio n), 8. (Indicate surface by proper subscript.)

L M N

~ = qbS Om =- qcS On=qbS

(yawing) (rolling) (pitching) 4. PROPELLER SYMBOLS Diameter D,

P, Power, absolute coefficient Op= ~D6

pn Geometric pitch p, Pitch ratio pID, Speed-power coefficient =.v p~: 0" Inflow velocity V', E fficiency Slipstream velocity 1/,

V"

R evolutions per second, r.p.s.

n,

T, Thrust, absolute coefficient OT = f D4

pn

Effective helix angle = tan- (2!n)

Torque, absolute coefficient OQ = ~D6

Q, pn 5. NUMERICAL RELATIONS 1 hp. = 76.04 kg-m/s = 550 ft-Ib./sec. 1 lb. =0.4536 kg .

1 kg = 2.2046 lb.

1 metric horsepower = 1.0132 hp.

1 mi.=1,609.35 m=5,280 ft.

1 m.p.h. = 0.4470 m.p.s.

1 m = 3.2808 ft.

1 m.p.s. =2.2369 m.p.h