mi\^L^1 ARE No. L5G25 NATIONAL ADVISORY COMMITTEE FOR AERONAUTICS WARTIME REPORT ORIGINALLY ISSUED September 19^4-5 ae Advance Restricted Report L5G25 Wnro-TUUKEL mVESTIGATION OF COUTROL -SURFACE CHARACTERISTICS XXIH - A 0.25 -AIRFOIL-CHORD FLAP WITH TAB HAVIKG A CHORD TVTECE THE FLAP CHORD ON AN NACA 0009 AIRFOIL By M. Leroy Speanann Langley Memorial Aeronautical Laboratory Langley Field, Va. WASHINGTON NACA WARTIME REPORTS are reprints of papers originally issued to provide rapid distribution of advance research results to an authorized group requiring them for the wax effort. They were pre- viously held under a security status but are now unclassified. Some of these reports were not tech- nically edited. All have been reproduced without change in order to expedite general distribution. L-i*? ■ tOCUMENTS DEPARTMENT Digitized by tlie Internet Arcliive in 2011 witli funding from University of Florida, George A. Smathers Libraries with support from LYRASIS and the Sloan Foundation http://www.archive.org/details/windtunnelinves FACA AR? No. L5G25 NATIONAL ADVISORY COr/DVIITTSE FOR AERONAUTICS ADVANCE RESTRICTED REPORT V/IITD-TUMIEL INVESTIGATION OP CONTROL-SURFACE CHARACTERISTICS XXIII - A 0.25- AIRFOIL-CHORD FLAP WITH TAB HAVING A CHORD TWICE THE FLAP CHORD OM AN NACA OOO9 AIRFOIL By M. Leroy Spearman SUMMARY Wind-tunnel tests have been made to deterr.lne the aerodynsmic section characteristics of an NACA OOO9 airfoil with a plain flap having a chord 25 percent of the airfoil chord and a iaalancing tab having a chord 50 percent of the airfoil chord or 200 percent of the flap chord so linked that the tab would deflect at a given rate with respect to the flap. Three linkage ratios were tested on the model. The tests indicated that the flap and tab could be linked to give hinge-moment balance with flap deflection and with angle of attack rind yet have greater lift effectiveness than a plain flap of similar size with a conventional balancing tab having a chord 20 percent of the flap chord linked to give hinge-moment balance with flap deflection only. INTRODUCTION The problem of closely balancing control surfaces to reduce the hinge moments, and consequently the stick forces, with a minimum loss in lift due to the action of the balancing device is becoming inci'oasingly importtXit, An extensive investigation of control-surface character- istics is being conducted at the Langley Laboratory of the National Advisory Committee for Aeronautics in an attempt to solve this problem. A briof summery of the characteristics of some of the balancing-tab arrangements investigated to date is presented In the following paragraohs. NACA ARR No. L5G25 .It is 3uggestGd in refei'-encs 1 that a control surface overbalanced hj a large overhang with a tab deflecting in the same direction as the flap might produce high lift at small deflections. This errgngement was tested in the Lnngley 7- ^y 10-foot t^onnel on a i'inite-span tail (refer- ence 2) and the results indicated that satisfactory control-surface characteristics could be obtained over only a small flap-deflection range. Tne flap deflection was limited by the air-flow separation vi/hen the overhang protruded into the air stream. Previous tests (reference J) have shown that small- chord plain flaps at high flap deflections can produce as much lift as large-chord balanced flcps at normal deflections. The high deflections of the small-chord flaps gave excessive hinge moments for large airplanes, however, and c sm^ll-chord flap combined with a balancing device that would not pi'otrude into the air stream or limit flap deflections therei^cre appeared to be a possible solution of this problem. An analysis presented in refei'ence 2 indicated that hinge-mom.ent balance with flap deflection as vi'ell as with angle of attack cou3d be obtained by linking two flaps to or)erate in opposite directions with the chord of the larger flap twice ttie chord of the smialler flap. With this arrangeiaent the smaller flap vvould produce the lift and the larger flap, linked to move only slightly, would serve as a balancing tab and trimiuing surface and ivould not protrude into the air stream as would an overhang balance. The calculations indicated that this flr,p arrangement, linked to give complete balance, would have greater lift effectiveness than a plain flap of similar size with a conventional balancing tab having a chord 20 percent of the flap chord, (See table I.) Another advantage of this tyoe of flap arrangement is that the weight of the forward flap might be utilized as a mass balance for the systemx, and thus the need for additional concentrated weights might be eliminated. The purpose of the present investigation is to determine tho characteristics of a plain flap with a tab having a chord twice the flap chord through a wide range of flap deflection and angle of attack and thus to provide a check on the aiialysis of reference 2. NAG A AR;-? No. L5G25 COEFFICIENTS AND SYMBOLS The coefficients and symbols used are defined as follows : Ct^ airfoil section lift coefficient Iqc/ / ^f \ Cji^ flap section hine;e-r:ionient coefficient 5 i • - VqcfV Ch+. tab section hinge -mon.ent coefficient ( =) ^ ' Vqct^/ 0]^ section iiinge-rcomont coefficient of flao snd tab combination ( / h vqcfV whe re I airfoil section lift hf flap section hinge rriorcent about point at distance d from tab hinge axis (fig. 1) h^ tab section hinge moment about tab hinge axis h section hinge moment of flap ?xid tab combination about ]5oint ?.t listaiice d from tab hinge axis (fig. 1) c chord of basic airfoil Cf flap chord (0.^5^) ct tsb chord (O.^Oc) q dynamic pressui^o and ttg angle of -'/tteck for hlr-foxl of rinfinite aspect ratio 5|. flap deflection with respect to tab 5t tab deflection with respect to line from tab hinge line to pivot point of flap k NAG A AiU No. L5525 5^ tab deflection v/ith I'espect to airf oa 1 when 5^ = d distance from hinge line of tab to hinge line of flap d' distance from hine;8 line of tab to pivot point of flap and ""In = a Vda^)/; o/df ■16 f^^'A f^o = VTgT Cli /dci-^\ Vdan 5f The sub3cripts outside the parentheses represent the factors held constai.t during the moasurement of the parameters . APP.\R..'iTUG MD PROGj]DI.tRE Mode 1 The 2-foot-chora by lj.-f oot-span model (fig. 1) u'es tested in the Langlcy .'4.- by 6 -foot vertical t^'onnel de.scribed in reference I4. and was made of laminated maliogany to the NACA OOO9 profile. The model was equipped v^ith a 0,25c flap and a 0.50c or 2,00cf tab. For the gap-open tests the gaps between the airfoil and the tab and between the tab and the flap wex-'e 0.005c. The flap and tab v/ere deflected in opposite directions in a manner similar to that for conventional balancing tabs by i.-ieans of the linkage system shown schematically in figure 1. The inodel v/as so arranged that the position of the flap pivot point could be moved upward, v/hich in effect deflected the tab upvi/ard 5°., 10°, o-r 15"^ (measured in each case when 5f = C°) for trimming. The range of flap NACA ARR No. L5G-25 deflection availsble v/as not affected by changing the position of the flap pivot point. The flap deflection for any given tab deflection can bs obtained analytically for each linkage. If d and d' are as indicated in figure 1, sin 4- tqn Gf = (1) - £- + cos 5t and the ratio of tab deflection to flap deflection is o5t '^cos 5t - -gT; (1 - ~ cos 5t i cos^Sf Regai'dlefDS of t}:e linkage systerr; used, the hinge moment of the flap and tab combination will be unchanged provided the value of -v^^— remains lonchanged. In order to test different rates of tab deflection, the distance d' was varied. Tab deflection ai:id the ratio of tab deflection to flap deflection, as calculated by equations (1) and (2), are plottsd against flap deflection for three linkages in figure 2, Test Conditions and Equipment The tests v/ere made at a dynamic pressure of 15 po'onds per square foot, which corresponds to a velocity of 71 miles per hour under standard conditions. The effective Reynolds number for maximum lift coefficients for these testw=! was approximately 2.57 x 10°. (Effective Reynolds number = test Reynolds number x turbulence factor. The turbulence factor for the Langloy ij.- by 6-foot vertical txonnel is 1,95' ) The airfoil model when mounted in the tunnel com- pletely spanned the test section, 'Ji/'ith this type of installation, tv/o-dim.ensional flovi' is approximated and section characteristics of the model can be determined. NAG A AR-i No. L5G25 Tesbs were irsde of the configurations indicated in tab].e II, The deflection rates are given for aero flep deflection. Measurements were made of the lift, drag, pitching moment, and flap hinge rroinent but, sines the present investigation is concex^ned neinly v;ith lift nnd hinge -moiaent characteristics, only values of lift ;and hinge moi'iient are presented. Corrections An experimentally determined tunnel correction v/as applied to the lift. The angle of attack and hinge moments were corrected for the effect of streanline curvature induced, by the ti.innel myalls in accordance v/ith a theoretical analysis similar to that pre;-'ented in reference 5 ^ov finite-span models. The tunnel-v/all corrections Yiere applied in the following inanner: Co ~ cton. + (o.21c^,p ■• O.I56CJ, cj = (0.965 - io.OOTcj./l) c^,^ '^h - ^hrn + O.IO52P C l.n where ao,p messured ajigle of attack Cj meesurecl lift coefficient c lm.„ raf-asured lift coefficient caused by flep dei'lsction (measured arbitrarily at aon = -8*^) qy,^_^ riieosured hinge -miOmsnt coefficient and p is a constant that is a function of each linkage arrangement and 5s reiver, in the follov'/inp; table; d5t/d5f I'' -0.10 -.15 -.20 -0.0528 -.009).^ .0056 i NACA Ar-"! Ko. L5a25 DISCUSSION AND RESULTS Theory Th3 following analysis wss originally presented in reference 2 but ic repeated here, in sljghtly different foi'rri, for clarity. In selecting the optimum size of bslancing surface to use in connection with a flap, the lift as well as the hinge moments of the balrncinr surface and the flap must be considered. It is shown in reference 2 that the greatest lift effectiveness ic obtained from a 0.25c flap with a 0,50c tsb. Reference 2 indicates also that, with this arr'angement, the ninge-moment parameters could be made almost zero. The follov:ing general reli^tions can be shown to hold for any two flaps hinged in series where the subscripts t and f ar'e used for the forward and recrward flaps, respectively: ^ 3 ^ + i^ ^ (3) d5^ 65f t6^ 65f p dao o tto Acio \cfy 66f 2 (ll-) dch _ 6ch^ /cA^ d5t /ocht 6bt cicht\ ochf 65t + f — I ( + 1 + ( 5 ) d5f d5f \cf/ 66f V^^t 65f <^Sf/ dCt ^^f The solution for -r— ^ from equation (S) that results dcb -'• in -TT" = yields two roots. This result indicates that d6f -" there are two vrlues of rstio of tab deflection to flap dch deflection which will give -^^ = 0. One root f?ives a ± negative value of ttc, which corresponds to the arrajige- ment tested; the other root gives a positive a^ , which indicates that the lift comes from the forwsrd flap and the balance from the rear flap as is the case v/ith a conventional balancing tab. (?or the arrangement tested, the normal tab end flap positions are reversed.) 8 NAG A ARR No. L5G25 The results obt?.ined with equat3.ons (J) and (I4.) are presentod in figure 3 fo^ various values of the tab-to- flap linkage ratio. The hinge-moment data as presented in reference 2 were not corrected for the effect of streaiiillne curvature resuj.ting from the jet boundaries. This streamline -curvature correction was applied to the data of reference 2, hov/ever, for the computed curves in figure 3* The ratio -^q-^ was varied from to -O.25 in order to compute the aerodynajiiic characteristics presented in fip'ure 5» On the model tested, the ratio -tt" = -0.10, -^ ' oSf ' -0.15, and -0.20 were used to ensure that the ratio at vviriich C}2„ send cj^e become Z3i=o could be fo'-ind. Test Results Lift.- The lift chsractsri sties are presented in figures ij. to 7 ff^^ 0.0050 gaps and figures 8 to 11 for sealed gaps. The lift parameters are given in table III and are plotted against linkage ratio in figure 12. The parameters were measured at cj = since deflecting the tab for trimrriing shifted the curves so that; the linear range of coefficients occu'-red at a higher angle of attack. For all tab trim positions the rate of change of lift coefficient v.'ith flan deflection cjk increased as the linkage ratio decreased. As would be expected, the slope of the lift curve c^ remained almost unchanged arid consequently the lift effectiveness of the flap a5 increased as the linkage ratio decreased. The flap vvras fairly effective up to deflections of about 20^ and the effectiveness at larger deflections was improved as the linkage ratio decreased. Sealing the gaps increased cJq^, cjg, and ag. Deflecting the tab for trimming had no effect on cj_, C7,g, or as, but the lift carves became increasingly nonlinear m the negative lift range as the tab was deflected more negatively. This effect is the result of air-flow separation that is probably caused by the break in the airfoil contour at the 0.50c st^-Lion, which results from deflecbing the tab. The s fjme effect on the lift curves can be seen as the camber Increases for airfoils having maxlm^'om camber at the 0,50c poixnt (reference 6), Moving the tab trim position negatively shifted the lift curves so that greater nopative lift, which is desired for a horizontal tall near the ground, could bo NAG A A?R No. L5G25 obtained in tlie landing sttitnds. This method of tritnming is about 75 percent as efrecfcivs as sn adjustable stsbi- lizer. With the tab deflected approximately -10^ or more the elevstor control through the deflection range tested is Insufficient for obtaining zero lift for the horizontal tail, unless the surface is at a positive aiigle of attack (as v/hen nser the ground). This effect v^ould be important in the case of a wave-off condition, since the tab trim position would probably be changed by 3 fairly slov; mechanic 3l method end the pilot mif;ht not have adequate elevator control. The characteristics for a Oo'^^Oof conventional bal?ncliig tab were computed from equations (3)j ih) > and (5) and are compared with the chf.racteristics predicted for the 2.00cf balancing tab in table I. As predicted by the analysis, a^ for the 2.005^, bal.rjn.cing tab is about 25 percent greater thaii for the 0.20cf conventional balancing tab linked to ^^'ive hinge -laoment br.l.9r.ce with flap c3eflection only. Ki nge moment s . - Hinge-moment characteristics are presented in figures Ij. to 7 fo^' O.OO^c gaps and figures 3 to 11 for sealed gaps. A. list of hinge-moment parameters is given in table III and the variation of hinge-momeiit par "meters with linkage I'atlo is shov.Ti in figure 12 for each tab trim deflection with the gaps open and sealed. The variation of hinge-m.oment coefficient v^ith lift coef- ficient for various angles of attaci-: at two tab trim settings and two ratios of tab deflection to flap deflection with the 0.005c gaps and the scaled gaps xs shown in figure IJ. The hinge -moment curves differ from the usual hinge - m.cment curve in that c}.^^ becomes ..lore nearly zero (and in some cases even positive) with the flap deflected than with the flap neutral. The values of ch^ tended to become m.ore negative as the linkage ratio c5t/o5f approached zero. Nearly complete balance was generally obtained at a ratio of tab deflection to flap deflection of -O.I5, which is in agreement with the analysis presented in reference 2 and with the results shovm. herein in figure 5. The decre^3e in cv,,^ as the linkage ratio approaches zero is to be expected because the at.-Lount of balancing moment contributed to the f ] ap by the tab is reduced &s 10 FACA ARR No. L5G25 the pivot point (fixed relative to nisin airfoil) of the fli-ip moves forv;ard. For each linkage ratio the hinge rfioii.ent caused by flap deflection becomes more ne:5atlve raioidly at deflections of about 10° for the 0.005c gaps and about 15° for the sealed p.-aps. This effect is probably caused by air-flo-v separation over the flap, as has been generally observed on other airfoils having hiejhly balanced flar^s. For a lin]cap;e ratio of -O.I5 with the tab trlmiaed at 2;ero, the l.\in.?e moments are very closely balanced for deflections up to about 10° or 15° tliroughout the angle-of-sttack ra:ape. The value of ch^ becom.es more ne^^ative as the linlrage ratio aecreases. This effect is the result of the decrease in balancing moment produced on the flap by the tab and also of the decrease in the amount of flap area ahead of the fixed pivot point. The balancing moments decrease as the pivot point of the flap moves forvrard and the effect is similar to that of decreasing the size of an overhang balance. Deflecting the tab for trimming had little effect on ciiQ^ and chg measured at the angle of sero lift. As the tab is deflected negatively, hcvvever, the hinge moments become more closely balanced at higher positive angles of attack. Vv'ith this arrangem.ent, higher lifts at large angles of attack could be obtained with less hinge m.oment than could be obtained with the tab trimtried at zero. Siich a variation is desirable for landing when the present system is used as an elevator, or for trimming the yawing mom-ent due to slipstream rotation when it is used as a rudder on single-engine airplanes if the rudder deflection and angle of attack sre of opposite sign. Sealing the gaps (fig. l'^ ) generally gives a more positive vaiuo of Cv,^ for initial tab trim deflections ■^0 of both 0° and -15°. The effect on ch^^ of sealing the gaps was not consistent, hov;ever, since the inci-ement was negative for o^ = 0^ s:nd positive for 5^- = -15°. CONCLUSIONS Tests were made of an NACA OOO9 airfoil with a flap having a chord 25 percent of the airfoil chord ( 0.25c) KACA A:^'"! No. L5G25 and s tab ha^'■ing; a chord 200 percent of ths flap chord (2.0Ccf). The following conclusions were indicated: 1. A flao with a S.OOcf balsncing tab could pi'oduce hinge-moment balrnce with both angle of attack aiid flap deflection and yet havo greater lift effectiveness than a flap of similar size equipped with a 0.20cf con- ntional balf-:ncing tab linked to give hinge-moment lance with flap deflection onlj. ver ba 2, Deflectin^j the tab for trimming was about 75 percent as effective as an adjui;table stabilizer. 5. The most nearly compleir-e balance was obtained at ? ratio of tab deflection to flan deflection equal to -O.I5, P3 had been Indicated by a previously published analysis, I4., Sealing both gaps generally iii creased the slope of the lift curve cj,^ and the lift effectiveness of the flap 05 and gave more positive values for the rate of change of hinge-moment coefficient with flap deflection ch^. 5. With bhe tab deflected nogr.tively for trim, the hinge moments v/ere closely balanced at high positive angles of attack, which Is desirable for the landing condition. Langley Mem-orial Aeronautical Laboratory National Advijory Corrimlttee for Aeronautic: Langley Field, Va. 12 NAG A ARR No. L5G25 REPER3NCES 1, Sears, Richard I., ?nd Hoggard, H. Pege, Jr.: 1/Vind- Tunnsl Investi.^Taticn of Control-Surface Chargcter- istics. IT - A Lsrge Asrciynamic Balance of Various Nose Shapes with a JO-Percent-Chord Flap on an NAG A OCO9 Airfoil. HAG A Al^R, Aug. 19'll. 2, Sears, Richard I.: Vvind-Tunnel Data on the Aero- dynamic Charactsristics of Airnlarje Control Surf sees, KACA ACR No. JLOS, 191^5. 3, Sears, Richard I., and purser, Paul E. : Wind-Tunnel Investigation of Concrol-Surf ace Characteristics. XIV - NAG A 0009 Airfoil with a 20-Percent-Ghord Double Plain Flap. WAG A ARR No. 3P29 , I9I0 . 1;, Wonzinger, Carl J., and Harris, Thonas A.: The Vertical Wind Tunnel of the National Advisory Committee for Aeronautics. NACA Rep. No. 587, 1931. 5. Swsnscn, Robert S., and Toll, Thomss A.: Jet-Bouiidary Corrections for Reflection-Plane Models in Rec- tangular Wind Tunnel,:j. 1\[ACA ARR No. 3S22, i9i;3. 6. Jacobs, Eestmar. N., Ward, Kenneth E. , and Plnkerton, Robert M. : The Characteristics of 7O Related Airfoil Sections from Tests in the Variable- Density Wina Tunnel. NAG A Rep. No. libO, 1933. NAG A AR;^ Ko. L5Q25 TABLE I COKPUTED CHAPiACTSRISTICS OF A 0.25c FLAP WITH A 2.00cf I^ID A 0.20cf TAB ctAr d5tA.5f "5 L ^^^^ 4 L ^"^5 1 0.20 2.00 -0.93 -.16 -0.33 -.li.O -0.0065 .0001 i TABLE II TAB TRIM P03ITI0!I3 AND DEFDHGTION RATES TESTED (deg) o6^/6of Gaps Figure -0.10 Open ^(a) -.15 1 (b) -.20 i \'/(c) -5 -.10 1 5(a) -S -.15 -.20 ! -16 -.10 6(a) -10 -.15 i(b) -10 -.20 V/(c) -15 -.10 7(a) -15 -.15 (b) -15 -.20 \/ \ He) -.10 Sealed 8(a) -.15 i (b) -.20 I \/(c) -5 -.10 1 1 9 -10 -.10 1 10 -15 -.10 ll(cO -15 -.15 1 i (b) -15 -.20 \/ \Hc) NAT I Oil AL ADVISORY COmiTTEE FOR AERONAUTICS iJi TABLE III .■AC A AHll '■'o. L5Ct2S LI'^T />SD HTNG3-M0M3MT PAR.mETERS FOR A 0.25c PLnIN FLAP WITH A 2.00cf TAB CN Al^J NACA OOO9 AIRFOIL IK THE LANGLEY )+- BY 6-FOOT I'SRTICAL TUI^EL C on f 1 gur a t i on ^7 ^^6 0.5 'K ^■•^5 1 05^/6 5 f (deg) Gaps open -0.10 G.090 1 0.0370 1 -O.ii-O -0.0015 -O.CO38 -.15 .092 .0320 -.35 .0007 .cop!. -.20 .095 . 0265 -.23 .ooMj -.0006 . 0049 -5 -.10 .039 .0505 -M -.00i|2 -5 -.15 .091 .0350 -.56 -.ooos .ooli^ -.OOOIl -5 -.20 .089 .0275 -v^l .COul^ -10 -.10 .092 .037c -.40 -.0016 -.0040 -10 -.15 .091 .03liO -.37 .0007 .0010 -10 -.20 .091 .0270 -.30 .001^2 .00.'4,3 -15 -.10 .094 .0360 -.38 -.0022 -.003L -15 -.15 .093 .0320 -.^.4 .0005 -15 -.20 .095 .0275 -.29 .OOl+l .^049 !.I -ps sealed -0.10 0.096 0.0)+10 i -0.1^3 -0.0018 -0.0026 -.15 .097 .0385 -.[lO .0005 .colli i -.20 .096 .03SO i -.;6 .0^85 -,ko .01^20 -.I,'i . 00L|.6 .0051; -5 -.10 .097 -.0016 -.0032 -10 -.10 .097 -.0014 -15 -.10 .099 .0Il20 -.I'.2 -.0018 -.0035 -15 -.15 .097 .0380 -.^-.9 .0012 .0007 i -15 -.20 .099 .03)45 1 -.35 .OOlei; .0049 , NA'^IOIfAL ADVISORY COMMITTEE FOR AERONAUTICS NACA ARR No. L5G25 Fig. la-c -Hinge axis- (q) Chord dimensions of airfoil. Pivot points (b) Position of tab when used for trimming. ^f-0°. (c) Definition of deflection symbols Pivot point fixe d relative to main part £ of airfoil NATIONAL ADVISORY COMMIIUE fOR AEBONAUIICS Figure ].- Arrangement of 2.00 Cf tab model for various deflection rates and tab trim positions. NACA 0009 oirfoil. Fig. NACA ARR No. L5G25 ( LU hen 6r = 0' ') -O.jO^ s 1 l_ /5^ "^^ ^ — 1 \ -S ^ -Id ^ CL :S ^ r22 -26 ~~ T — - _ 20. ■"~~~^ " — ' - . \ ~^ ^^ '^ -r ' •^ ^ \ dSf n.K * -2 c o :::;^ C -^_^ X ^ -^ ^ [^ 1 < ^ M \ t^\ ' S .04 -*— ir Q) e O 5 ^1 c ■ .04 ^ c o .08 <.. ,^ ^O ~ .12 . .16 -20 -16 16 20 -12 '8 -^ O 4 3 IZ Angle of attack , cx^, ^^9 fa ) Gaps , 0.00b c ; Mo - 0°: d^t/^Sf --0.IO. Concluded. Figure 4 . - Continued. Fig. 4b N'ACA ARR No. L5G25 -16 -12 -B> -4- Q> 4- b II An^/e of offQcK.cxo.deg (b) Gaps, 0.005c, 6to= O'i hSt/h£f = -0./5. r/jure 4.- Continued. 16 NACA APR No. L5G25 Fig. 4a Cone. o .c ■ c o 16 20 -20 -lb -12 -8 'A O 4 e IZ Angle of attack , o^o, deq fa ) Caps , O.OOS c ; ito - 0°; d^t/^^r --0>0. Concluded. Figure 4 . - Continued. Fig. 4b NACA ARR No. L5G25 -c- 1 Vo 0) g c C) -c- S:: 't-- <»3 t-: CI o "O r-fif -/6 -IZ -S -'f 4 & IZ An^/e of otfQcK.cxo.deg (b) Gaps, 0.005c, 6to- 0°; hS^h^f = -0./5. r/jure 4.- Continued. 16 NACA ARR No. L5G25 Fig. 4c ~c .IZ o ' ^"^ Qj ^ ■OH cv^ c -^ ^^ 04 Qj c: ^ o ^ 03 ^ ^ ^ ^ ^ -.Of ^ -.06 /.£ 1.0 .8 G i^ / / N 3 A / N v A / / / / / "^ S i / / / ^ / {/ / / / 3 A \ 1/ ^ J / / ^ SI ^ Y / A / / A / / / h / \a / 1 / ^ ' / / / A / I- A ( y h 'a \ A v A / 20 / / / A A / } V } / A \\ \ / / ^/ 1 / / / /, / / / / /■ h / k / A 3 1 / / /■' 10 1 i v / / / / / ■ ^ / / A A v / / A 'i \ /, I ' 7\ / /, / ^ / / / / A A r / / '' } \/ / ~--vJ / / / / / / c t — o A 10 / '/ /I ^ / f / V, /. 20. , r^ / 30 aMMf IIUNAl TEE F( R AERi UKV NAUTl S •—A lb 20 -20 -\h -12 -8 -4 O A 8 12 Angle of attack .Ocq, deg (a) Caps, 0.005 c ,8to- -5° ; W^^f = 'O-IO . Figure 3.- Aerodynamic section characteristics oF an NACA 0003 airfoil having a 0.25c flap and a 2.00 Cf tab w/fh various linkages. NACA ARR No. L5G25 Fig. 5a Cone, U 20 -12 -8 -4 O ^ 3 Angle of attack ^ cx^j ^^9 (a ) Caps, 0. 005c ■ Sto - - 5 ; SS^/dif. = -o.lO. Concluded Figure 5. - Continued. Fig. 5b NACA ARR No. L5G25 O 3; \ ^ ^ X -16 '/e /6 ZO ■S -4 4- s /e. /ing/e of oH-ack, o^ , degf (b) Gaps , 0.005c ^ Sto'- -5^■ d^t/dSf - -0.15 figure 5 - Continued. NACA ARR No. L5G25 Fig. 5b Cone. ^^S s w. o ^ s ^ ^ Vi ^ r^ O O o OO O o ^.^ OO ^■^ OO ^'0.20. r/gare 5.- Contw^/ecf. NACA ARR No. L5G25 Fig. 5c Cone, ^ f\2 00 T5 CD o -3o o fv So c\^ ^o ' \[j^d\d\^^dOd ^udUuouj-d6u!H uoipa^ Fig. 6a NACA ARR No. L5G25 10 8 .6 ^ .2 c Q) «o ^ '.12 -.16 U 16 20 -20 -16 -12 -3 -^ O 4. 8 Angle ofatfack, cx^.deg (a) Gaos, 0.005c , Sf^ = -10°; dSt/^Sf= -OJO. Concluded. FigurQ 6.- Continued Fig. 6b NACA ARR No. L5G25 -6 -^ ^ 8 /Z ^ngle ofoffQck,cx^^c/ej (b) Gaps^aOOSc; Si^^-iO" -, bSt/hhf = Figure 6- Continued. IS 10 0.15. NACA ARR No. L5&25 Fig. 6b Cone, (deg) o 20 Angle ofQffQck,oco,cieg (b) Gap^, 0005c- Sto-iO"; Mt/hSf--O.I5. Concluded. r/gure 6- Continued. Fig. 6c NACA ARR No. L5G25 to -IZ '6-4-0 4^ 8 /2 /6 ZO /ingle of aHach,cxo,c/Gg (c) Gaps, 0.005c, Sto=-\0°, hSt/hSf^-0.20. r/gure 6- Continued. NACA ARR No. L5G25 Fig. 6c Cone. ■V. t/hif - -0.10 . figure 7- Aerodynamic section characteristics of an NACA 0009 airfoil liav/ng a 0.25c flap and a 2.00cf tab w/th various linkages. NACA ARR No. L5G25 Fig. 7a Cone, ^ C I I c: o CO (deg) o 20 " 15 -IZ -8 -4^ 4 d /a 16 ZO 2^ /lncj//e of attack, (Xo,a/eg fa) Caps] 0.005c ; Sto '- '/5^• hH/hh^-0. 10. Concluded Figure 1.- Continued. Fig. 7b NACA ARR No. L5G25 -8 -f f 8 /2 16 hng/e of atfQcli,Q ^/' / y / / ) ' / / / / -2 A if / \( \ / I / / ^ / ■A ^ '/ ^ y /i V ^ ■^ V / / h .6 1 f /. / /J / / / -.8 / / V / ID V, / com UoN/ nE£i . ADV 0RA£1 SORY ONAUI CS -/6 -12 12 16 -a -4- 4 8 Angle of attack ,cxo, deg (a ) Gaps sealed , Sxo = 0° j ^Sf/^Sf = -0.10 Figure 3.- Aerodynamic section characteristics of an NACA 0009 airfoil having a 0.25c flap and a 2.00 Cf iab \Nitti various linkages. Fig. 8a Cone. NACA ARR No. L5G25 if (deg) o ^ 5 ° \0 ' 15 o 20 np> "^ ^^ .uo * 30 -♦»- c~ .04 r-, .0; \ \, ^^ C \ vj -^^ > — -c _^ V § '\.. ■* V^ ~~~~^> =-c r "i r — 1 p — j::;::;;^ ^ , a-^ (dec j) ^ ^ 'DA -OS :/2 t ^^^^ ^^^^ "^~~--) ^ ^ ».,^^ T,^^^ h -5 8 \ ^ '^ \ r/C 3 \ N, i >^ '/J \ \ *~~~~ ^-. > — N o \ ■^ ^ H K r^ -C^ 7 J ' -.16 \ -~~-t - — ^ — + i ^25 ~~~-+''' po -;6 -\2 -8-4 4 3 12 Ih Angle of attack , ocodeq ■^ ' '■'' J NATIONAL ADVISORY CO MMIHE E FOR AERON 4UTICS (a) Caps sealed , ko' O^j^Sf/d^^ -0.10. Concluded Figure 8 . - Continued NACA ARR No. L5G25 Fig. 8b c: I c: .06 cr •Si o o o I I -20 -16 -12 ^ -8 -4 4 8 Angle of attack , ckq , oieg (b) Gaps sealed -, St^^ 0° ; l^t/^Sf = Figure S.~ Continued . 12 /6 0.\5 . Fig. 8c NACA APR No. L5G25 c: .12 .03 .04 .04- 1.4 12 1.0 .5 .1 I .4 .2 .2 A -.6 -.8 -10 -20 -IG -12-8-4- 4 8 Angle of attack ,cxio , deq (c) Gaps sealed-. Sto= 0° ; ^k/dSf --0.20 Figure 8.- Concluded. IZ 16 20 NACA ARR No. L5G25 Fig. 9 «♦- - c CO ^ ■20 -16 -12 -6-^043 Angle ofaiiack , a) o <<} -.2 "H^ s- o -.4 -4»„ -25 < -30 — — /T^ /I r-- ^ 1. L I 1 / 7 / [^ i 7 V A k-(v- / / /] r 1 h [','1 \ \ A / 1 / 7 h 7 7 < \l 7 7 / / /; h f 1 / /, r 7 7 / o ic \^ 'h / /' / 'I c 1 /, \ 7* M 7 i G j V 7 / / 7 ^ it / 15 / i N 1 ( / ■ / / o I / / / ,/ /J g / / / ft \h \h f/ r i A 1 5 / // ^ % / / /, ^ / f N A r ,<^ / / / / / \ c / / A / A / f K f "■< \ ^l / / / / A \\ f/ -^ v: ^ > 4 /4 -2 6 0- G ^ f' A Z / J '< ^ A 1 A ^ ^5 bo "1 ^ 1^ '// ""~" ■" ^ < ^ ^"^ I: / N COMM tnoM n££F AM )RAER ONAUT CS -20 -lb -12 -a -4 O 4 8/2 Angle of attack ^ o^lq, deq (c) Gaps sealed ; ko- -15° -, ^k/^^f - -0.20 Figure II.- Continued . 16 20 Fig . lie Cone . NACA ARR No. L5G25 O Si i I en c c -IZ -6 -4 4 B 12 16 20 Angle of attack ^oco^deg (c) Caps sealed , ko - - 15% i>S\/^^^ = -OZO. Concluded. Figure II.- Concluded. NACA ARR No. L5G25 Fig. 12a .040 .020 -.zo ^S -.30 -.4€ and Chs .0060 .0040 .OOZO -.0020 -.00 AO . — - — ' r- ' . ' . ^ " 1 ^ "- I ^ " -~-- "~ - — ^^-^^ -— ^ ^ — 1 . Gaps 0.005 c ' N, . S \ "^ ^ \ \ V \ \ s. fe ^i. COMI mm iinEE U. AO ■ORAI ISORY RONAU 1CS 1 s c hs N k -.20 -.10 -15 (a) Sf^~ 0° ;gaps open and sealed Figure 12.- "Variation of paramefQrs with rafio of iab defied ion ioflap deflection. ci'O. Fig. 12b NACA ARR No. L5G25 .040 C?5 .030 ,020 CXL -.30 .40 .0060 .0040 Cho, .0020 amd ^hg -.0020 .0040 1 7 . -^ '^ • -^ "^ -_^ — *— 3 ■ V, \ N \ \ \ \ \ V N \^ N N, ^ l\ ^hr^ \ s \, \^ \. ^^hs mm TIONAI TEEF )RACR PIUUTI ■3 -.20 -15 (b) Si^^ -5°; gaps, 0.005c Figure 12 - Continued . -.10 NACA ARR No. L5G25 Fig. 12c .040 <^1S .030 .020 Ocj -.30 .40 Choc and .0060 .0040 .0020 -.0020 -.0040 ( ' ' ^ ^ ^■^ ■^ — . ' 1 ts, ^ '>^ 1 -:n. N, ^ sN N k "N v^ \ "-^ Ch, X — \ \ 'Chi ' Hi COMM iTIONAI FTEEF )RAER JNAUT a -.zo -.15 .10 (c) 6t-'-IO°) gaps, 0.005c Figure 12. - Continued . Fig. 12d NACA ARR No. L5G25 .040 .030 .020 -.20 -.50 ' -.40 .0060 .0040 ' .0020 -.0020 -.0040 - a ■ r ^^5 — -- ■ ^. b"^ N \ 1^ V ^ K^^^?' \ ^ ■^ r N ^ Ch£ » «. m FORAi BOftr RONAU ncs COMI inEE -.2 w Figu ) s re \ to- 2. -/5 - L 'C/( 5 pe 5d n c ind -.\L d. NACA ARR No. L5G25 Fig. 13a 6^ <0 T3 ) gi / / gS / o c o i / coo^cooo / c 1 / 5 [ 1 1 'T^ 5 / ^ y^ / ^ •^ o <9 a a t> o V / / CD o 6 1 1 ( 5 . > II \ <^" < ^ -o-H o / . / w ^ / \ ^_ >in / / u / \/ 3 •-o^ i / ( 00 1 II § J/ G \ / \ '1 o o \ > i / \ r ' vO cv o o s § c\ S-. cv o I ' 1 * (0 » • oq o c O £ CD O CJ o +11 10 CTi <:5 ^ >- c .<» O U c o c a o o o d -c •+- c o -Q CT) c c a 2 s- o -f- ^ c -it: ^ ^ ■ *^ p- (I ^o ' :iudiDijj.30D :^uduuouj-eduiL{ uoi^od^ en O t^ Fig. 13b NACA ARR No. L5G25 A ^ ^ s / ?i 7 S "* -p / It 1?"^ A a^ou^ocQO^ o o M O \ <:;^ S'oooiQ^^ A -^ — ■ ^-^ 1 . \- i\ \ \ ^ I — i 1 \ I , 1 ^1 1 "o { \ \ \ \ \ \ ( 1 \ > \\ / < 3>-= ^ ' 9 •to 1 "o 1 SQ \ {/ e^ } ^ '-i^ K' ^ o ^ 4 1 c^ ' 6 00 O r 00 O r-J e .0) o o c o c\ VO ^o ~i o o VO T3 Q) a o m i^ ri cn ^O '■\Ud\DlJ^dOD ^UdUJOLU -oduiLf UO!:i.0S^ UNIVERSITY OF FLORIDA 3 1262 08104 998 2 UNfVERS!TY OF FLORIDA 'ti OOCUMENTS DEPARTMENT 20 MARSTON SCIENCE LIBRARY O. BOX 117011 A'NESVILLE, FL 32611-7011 USA . U^;'^'ERS!TY OF FLORIDA OOCUWENTS DEPARTMENT ■ 120 MARSTON SCIENCE lie; .^- RO.BOX117011 ''^^''^^ GAINESVILLE.FL 32611-7011 USA