^hc!\ L '^1 AEE No. L5J02 NATIONAL ADVISORY COMMITTEE FOR AERONAUTICS WARTIilE REPORT ORIGINALLY ISSUED January 19^6 as Advance Eestricted Eeport L5J02 EXPERIMEHTAL EETERMERATION OF THE EFFECT OF HEGATIVE DIHEDRAL ON LATERAL STABILITY AHD CONTROL CHARACTERISTICS AT HIGH LIFT COEFFICIEHTS By Marion 0. McKinney, Jr. Langley Memorial Aeronautical Laboratory Langley Field, Ya. '^NACA 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 war 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. DOCUMENTS DEPARTMENT Digitized by the Internet Archive in 2011 with funding from University of Florida, George A. Smathers Libraries with support from LYRASIS and the Sloan Foundation htfp;//www.archive.org/details/experimentaldeteOOIang Ill &ff ^/ NACA AH:^ No. L5J02 NATIONAL ADVISORY GOMPilTTES FOR A3R0NAUTIG3 '^u !C/\f "the model became increasingly difficult to fly. With an effective dihedral of -15° the flying character- istics ivere considered to be dangerous because, when there v;a3 only a slight leg in the appiicatlon of corrective control fcllovv'ing a disturbance,, the unstable moments resulting from, spiral instability becamiO sufficiently large to overpovver the moments of the controls so that return to straight flight was im.posslble. Inasmuch as full-scale airplanes because of their greater size will diverge at a slower rate than free-flight miOdels, the am.ount of nega- tive effective dUiedrsl that would constitute a dangerous condition is expected to be greater for full-scale air- planes. Increasing the directional sta.bility reduced the magnitude of the sideslip and improved the general flight behavior. In the negative effective-dihedral range, Increasing the lift coefficient fromi 1.0 to 1.8 had a slightly detrim.ental effect on the general flight -behavior of the miodel at any given value of effective dihedral and directional stability. NAG A A?.R Wo. L5J02 INTRODUCTION Tests cf modern i-'ilit^ry airplanes have li~idicated that large changes in dihedral effect ii.ay occur ever the speed rsnge of an airplsne operating under hlgh-po'»/er conditions. This chsnge in dihedral effect may cause an airplane thst has a noraial amount of positive effective dihedral in the high-speed condition to have large nega- tive effective dihedral in the flaps-dcMi, low-speed, high-power condition (v/ave-off, landing-approach, or take- off condiblon). Previous tests (reference 1) have indicated that slightly negative dihedral effect is net objectionable and that spiral stability is not import snt. It was desired to extend the previous v/ork to higher lift coef- ficients and to determine how i.-iuch negative dihedral could be tolerated without excessive detrimental effects on flying characteristics. Flighb tests of a model with variable dihedral heve therefore been conducted in the Langley free-flight tunnel. in order to determine experi- mentally the effects of various amounts of negative dihedrsl en the lateral stability and control character- istics of an airplane at hign lift coefficients. The results of this investigation are presented herein. These results are part of ?. rcioce comxT-ehensive investigation being made to detemine the effects of large variations of dtihedral angle, vertical-tail area, and lift coefficient on the laterr:l stability characteristics of an airplane. The present investigation consisted in pov;er-off flight tests of £. Tiodel on which the geometric dihedral angle x'vas varied from 0° to -20° for vertical-tail areas from to 55 percent of the vjing area and for lift coef- ficients of 1.0, l.''-i-, and 1.3. Sufficieno combinations of dihedral anp-le and t?il area vvere tested at each of the three lift coef f icienus to determine the effect of dihedral, tail area, and ±ift coefficient on the lateral stability and control characteristics over the range of the variables. The results of the flight tests of the model are oresentsd in the form of qualitative ratings of the general fli.gb.t bohavior of. the model for each test condition. I\TACA AH3. No. L5J02 SYMBOLS m S St b V q k... mass of model, slugs wing srea, squrrs feet vertical-tall pre ^ , square feet wing so an, feet f ree-s brean; velocity, feet per second /' 1 2 dynar^ic pressure, pounds per square foot '.ppV tiii.e to daar,p to one-half amplituJe for spiral divergence, seconds (negative values indicate time to increase to double ainolitude) radius of gyration of model about longitudinal axis, R D X r o r r radius of gyration of model about vertical axis, feet Routh ' s dis or iininant coefficient in stabilit;/ quartic equation, given in reference 2 coefficient in stability quartic equation, given in reference 2 roots of stability quartic equation yavving angular velocity, radians per second mass density of air, slugs per cubic foot angle of sideslio, degrees except whei''e oth.erv?ise specified rolling angular velocity, radians oer second flight-path angle, degrees geor.etric dihedral angle of r^aan-thickness line, degrees k NAG A ARR No. L5J02 / 111 |j, aiz'plane relstlve-denslt;/ factor pSb / m \ T tiine-convepsion factor ( _,,-/ lift coefficient ( — r-j Ct lift coefficient ( — r-] Cy lateral-force coefficient / Lat eral force qS / -, -, . . ^^. . . /Rolling Tiioment'\ C7 rolling-moruenu coefficient I ) ^ \ qSb / r r. . . ■ /Yawing inoLient\ C^ yawing-rp.oment coefficieni: I ~- j Cy^ rate of change of lateral-force coefficient with ^ angle of sideslip, per radian (6Cy/^P) Gi^ rate of criange of rollirxg-mcment coefficient with '^' angle of sideslip, per degree except where otherv/ise specified (^^C^/op) Grip rate of change of yawing -moment coefficient with ^ angle of sideslip, per degree except where '- otherwise specified (^Gn/6j3) Ci rate of change of rolling-moment coefficient v/ith 'P rolling- angular- velocity factor 6G7 \. Cn rate of chaiige of Yawlns'-mom.ent coefficient with rolling-angular-velocitv factor ( — r 1 \ 2V/ G7 rate of change of rolling-momient coefficient with yawlng-angular- velocity factor 1 — — ^ i \ 2V/ Q,y. rate of change of vawing-moment coefficient with vawing-angular-velocit";" factor/ — r 1 I ^rb ] \ 2V/ NAG A ART Fo. 7,5 JO 2 APPARATUS The investigation v/rs carried out in the Langley free-xlight ti.innel, which is ocuioped for testing free- flying dynamic alrplsne iixode.ls. A ccinplete description cf the tunnel and its operation is r;iven in reference 3. Force tests to deteriidna the static lateral stability derivstives were made on the Langley free-f light-tunnel six- component bslance, described in reference ii. This balance rotates v.ith the model in yaw, go that all forces snd moments are iTieasured with respect to tne stability axes. The stsbility axes pre an orthogonsl system of axes having its origin at the center of gi'avity in which the Z-axis is in the plane of symmetry -ind oerpendicular to the relative wind, the X-axis is in the olane of syii2!ietry and per-oendicular to the Z-axis, is "ceroendicular to the plsne cf syrmietr^^ J- ■ The coiitrcl used- on free-f light-t annel models is a "flicker'-' (full-on or full-off) system. During any one oarticulpr flight the control deflections in the full-on positions ev^ constant =-;nd the smount of control applied to the model is regulated by the length of time the con- trols are held on rather than by the control deflections used. A three-view drawing cf the model used in the tests is shown e-s figure 1 and photograxfns of the m.odel are presented as figures 2 to L|.. Figure 5 is a photograph of the Jiiodel, "A'ith a geometric dihedral angle of -1'^^ , flying -in the test section cf the tunnel. Although the m^odel used in the tests v/.-s not 9 scale model of any particular airplane, it approximately represented a - — scale model 10 of any current fighter airplane. "■■J For all tests the model was equipped 'A'ith a duplex flaT3 arrangem.snt consisting of a i+O-percent-chord double slotted flap located inboard over 1^.0 percent of the semi- span and a 20-percent-chord balanced split flap located outboard over Ij.2 oercent cf the semispan. The front and rear oortions of the double slotted flap were deflected JO and 70°3 respectively, with respect to the airfoil chord. The balanced sclit fls;o v/as deflected IiO^. The effective aihedral ^7^s changed by altering the geometric dinodr^al angle cf the v/ing. Four geometrically NAG A ARIi Ko. L5JO2 similFr V'^rtical tails and. two end-plete vertical tails were used on the riiodel to produce changes in directicnel stability. (See fig. 1. ) ' The liiodel relative-density factor and radii of gyration varied slightly during the test prograin between the lollo'/.'ing limits; li ■ ' . 8.10 to 8.92 0.161 to O.lSl D k-/ o.a+i to 0.290 The data "roresented in references 1, ^, and 6 indicate that changes of weight and moxrient of inertia of the magni- tudes involved in the ore sent investigation v/ould Kake no pronounced difference in the stability or flying character- istics of the racdel. TESTS Scope of Tests Flight tests of the luodel were rr.ads at lift coef- ficients of 1.0, 1.1^5 and 1.8 vv'ith the follo7/ing conibi- natlons of dihedral an.c;le and vertical -tail area: ; Ver-cical bail Off 1 k '4: Vertical-tail area, st/s Ore ome trie dihedral .05 .05 .10 •15 .35 (total) (deg) 1 -5^ -10 , -20 0, r; -IG, -15. -20 0, -5, -10 0, 0, -5, -10, -13, -20 '' -5j -10, -15, -20 NACA KRR No. L5 JO 2 7 The v8-lues of Cjr, and Cnr. oorre spending; to the vrrious test conditions were determined from force-test data and are presented in figure u. These data show that the tests covered a range of Cjo from O.OO52 to -O.OOI8 and a range of G;^-^,, from 0.0001 to O.OOob. The test range is P consider-ed representative of :jresent-day limits, 8.s shown by the data presented in figure 7- These daca shov; that the vax-'iation of On- and Ci of two high-oowered n^, "p. (200C bhp ) airplanes over their speed range falls almost within tne r3np:e of vrlues covered bv the tests. Testing Procedure The rr.odel was flown at each test condition by n^eans of ailerons alone and ailerons coupled with rudder. The rudder travels used were selected bj' visual observation of flight tests as the aiiiount necessary to eliminate the yawing due to aileron deflection and rolling. For tests in which the rudder control 'vas crossed (that is, left rudder apr-lied v/lth right aileron and right rudder apolied with left aileron), the rudder travel v^ras the same as that used for the coordinated rudder and aileron control at the same test condition. For the tail-off condition the ailerons were rigged uo 12*^ in order to eliminate the adverse yawing due to aileron deflection. The stability and control characteristics of the model v/ere noted by the pilots from visual observation, and motion pictures virere made of some flights in order to supplement the pilots' observations. The spiral stabilit7/ of the model was determined by the pilot from the rate £.t vmich the model, v.'ith contz'-ols fixed, sideslipped and rolled from level flight. An increasing rate of rolling and imvard sideslip was judged as spiral instability. The general oscillatory stability characteristics Vi?ere judged by the pilot from, the dam.ping of the lateral oscillations of the model after a disturbance. The model could never be allowed to fly 'with controls fixed for sufficient tim.e to allow m.easurement of period and dam.ping from the motion-picture records. 8 NAG A K-^/R I'Tc. LSJ02 Flight-behavior ratings bfsed on the pilot's opinion of the general stability end conrr'ol characteristics of the model were recorded for each test condition. Each rating was based on a n'oraber of separate flights. Although the accuracy of these i^atings depended upon the oilct's ability to recognize unsatisfactory conditions, it is believed that the ratings give a qualitative indica.tion of the effect of chances of the variables involved. Boundaries for neutral spiral stability (E = G), neutral oscillatory stability (R = 0), and neutral directional stability (B = 0) v/ere calculated over the test range by means of the stability equations of refer- ence 2 and are shov/n in figure 6. Lines of constant daniping of the Si^iral mode were also calculated for the model by determining the root of the stability quartic ^ that would give the desired value of damoing by the formula (from reference 2) X.zOi£iil and bv determining various values of G?^ and G- that " P ' P would give this root \ from substitution of the root in the stability quartic. The calculated lines of constant damping are sho^^n in fie.ure 3. ^Yp Values of the static -late: usee in the calculations vvere obbained from force tests of the rfiodel. The value of the rotary derivative Criy, was obtained from free-oscillation tests of the m-odel by the method described in reference 7- 'Ihs other rotary derivatives C^,^, Cn , £"^d C^. '.'vere estimated from the charts of reference 8 and the formulas of reference 'y . The values of the miass characteristics m, ky, and kr, vjeve measured for the m.odel. Values of the stability derivatives used in the calculations are given in table I. IT AC A ARR IJo. L5J02 9 RESULTS AND DISCUSS IO>I The variations of sf x'sctive-dihedral psvaneter Cjo P and directional-st ab Lli t''" psrc'i.ieter Cn were obtained np in the present investigation by changing the geometric dihedral sngle and ^'ertical-tail area. The flying characteristics, hov;ever, defend on the values of the stability derivatives, not en the inethod by which they were obtained; hence the flying characteristics of the model may be applievd to conditions - such as wave-off, talce-off , and Isnding-apprcach - in which negative effective dihedral is often c^-used by the high pov;er and high lift coefficient. The princl;rsl results of the present Investigation are given in figure o in the forni of ratings of the general flight behavior. All flight ratings not in parentheses were obtained with a total aileron deflection of 30°; those in parentheses v/ere obtained with a total aileron deflection of 50°- I'iiQ maximum values of pb/2V corresponding to the aileron deflections of 50° ^J^^d. 50° were determined to be about O.O8 end 0.12, respectively, from rcll-offs at a geoirietric dihedral angle of 0°, with St the verticsl tail having — = 0,15, and with coordinated S rudder-. It was, perhaps, net necessary to use f?n aileron deflection of 50° for all the test points at which this increased travel was used. '.•T'len it v/es found necessary to use 50° travel with a certain combination of dihedral angle and vertical-tail .area at a lift coefficient of 1.3, the seme travel v;as used at lower lift coefficients. Effect of Dihedral Although the model was observed to be spirally unstable for all conditions tested, the flight data of figure 8 show that very satisfactory flights were obtained st positive values of effective dihedral." The rate of spiral divergence for the conditions cf positive effective dihedral was observed to be small and the controls-fixed lateral motion was characterised by a slov/ gentle roll- off and sideslip from the steady state. The divergence coula be controlled reedxly by occasional application of a total aileron deflection of 50°. Under these conditions, the model was as easy to fly as if it had been spirally 10 EAGA ARR No. L5J02 stable and in the norrupl gusty air oi' the tunnel did not seem to require more frequent control than in a spirally stable condition. At snsll values of negative effective dihedral, flie;ht characteristics wei'e not much different from those at small values of positive effective dihedral and the E lo"-' spiral divergences were readily controlled by appli- cation of the aileron and rudder controls. The rate of spiral divergence, hov^ever, ?.'as found to become increas- ingly raoid with increasing negative effective dihedral until, at an effective dihedral of about -15^3 "the diver- gence was quite violent. As in the case of small positive effective dihedral, the motions were characterized by a roll-off and sideslip from steady flight. As the negative effective dihedral was increased, the rate of the diver- gence increased u.ntll, for the conditions having the larger negati\'e dihedral angles, the motion appeared to be as rapid as a fast aileron roll. As the negative effective dihedral was increased, the controls had to be ap-olied sooner after- the divergence was noticed because, when there v/as only a slight lag in the application of corrective control following a disturbance, the unstable moments resulting from spiral instability became suffi- ciently large to overpower 'the micments of the controls so that return to straight flight v;?as impossible. o It vtas found impossible to fly the m^odel with negative effective dihedral angles greater than about -10° (C7^ = 0.002) with a total aileron deflection of 50°. The rate of s;oiral divergence apparently had become great enough by the trme the nilot applied opposite control to make recover'y irroossible. The rate of divergence -was observed to be retarded v/ith aileron application, but the miodel continued to diverge. In order to obtain data for the whole test range, the total aileron deflection was increasea fromi 50° to 50° for all test conditions having a value of C7,.~>0.002. It was therefore possible to control, the spiral divergence over the comolete range of negative dihedral angles. Flight unaei"' conditions of 0^ > 0.002 v;ss difficult, however, because f].ying the model required constant attention to the controls. The largest negative effective dihedral angles (Cz,,- ~ 0.005) seemed to be the maximium for v/hich the model could bo flow-n with a total aileron ^TACA AHR Fo. L5J02 11 deflection of 5^'°, inasmuch as even slight delays in epolying lateral control allowed the raodel to continue to diverge. Many crashes therefore occurred during the tests at values of C?^ of about O.CO^. The general flight-behavior ratings in figure 8 were given when the rudder wa^s coorc'^inated with the ailerons in the norrrial rianjier (right rudder viith right aileron). The flight tests, however, shovved that using the ailerons alone for control or even crossing the rudder control irnproved the flying characteristics of the model throughout the negative dihedral range and irads the liodel sligiitly easier to control. This improveKient evidently took place because the sideslio resulting fro^a aciverse yawing opposed the Inwax'^d angle of sideslip caused by spiral divergence and, in spite of the adverse effect of rolling due to yawing, reduced the rolling divergence. This reduction of inward sideslip caused the response to the controls to bs improved. The large amplitude of the yawing motions caused by crossing rudder control, hov.ever, was objection- able to the f ree-f light-turinel plloos. Applying, opposite rudder with ailerons would probably be objectionable to the piloi: of an airpl.ane inasmuch as it is an upjiatural motion and would cause a loss of altitude. In a crucial m.oment, the pilot's reaction would probably be to apply coordinated rudder and aileron control rather than to thlnV: to a;oply rudder opposite to the ailerons. A pilot miglit, hov;ever, be trained to appl^y' no rudder with aileron control v'hen flying an airplane in conditions that are knov/n to give negative dihedral effect and thus obtain some improvement in the control response for recovery. The wave-off, take-off, and landing-approach conditions are believed to be dangerous for airplanes that have large negative effective dihedral because ^ when these conditions are encountered, there is onl./ a limited altitude in vvhich to aiD-;l;/- corrective control. To fly with as m.uch negative effective dihedral as was encountered in the present tests should be possible if the airplane ailerons are as power- ful as those of the model tested and if careful attention is given to controlling the airplane. To fly airplanes with greater negative effective dihedral angles than were encountered in the present tests iriight be possible inasmuch as the rate of divergence of the airplane would be l/v'N times as fast as that of the model, where N is the scale of the model as 10, 15, etc. l;o information is available, hov/ever^ concerning the relative reaction time and the 12 NACA ARR No. L5J02 tirri8 to deflect the controls for free-f light-tunnel r.nd airplsne pilots. Inasmuch as there has been no correlation of the boundaries of the region in vvhlch flight is pos- sible in the Langley free-flight tunnel with time to dainp, extension of the results to more negative dihedr^al angles has not been attempted. Effect of Directional Stability Increasing' the dix-^ectional stability Cv-, Imriroved np the general flight behavior of the model over the range of dihedral angles and lift coefficients tested, as shown in figure 8. The tests showed that for the range of positive effective dihedral angles tested adequate directional stability vjbs more desii-'able than the slightly lower rate of spiral divergence associr-ted with lov/er directional stability, becr.use excessive yawing was encountered with low directional stability. The rates of spiral divergence encountered in the oosltlve dihedral range were, as previously discussed, quite slow even with a high degree of directional stability. I'v'hen the effective dihedral was negative, however, increasing the directional stability was observed to cause a slight redaction of the rate of spiral divergence. This reduction is in agreement with the calculations of the spiral stability, as sho?/n by the increase in time for the motion to increase to double emplitude as G>-i Increases. An analysis of the general flight-behavior ratings and the cslculated lines of constant damping of tlio spiral divergence indicates that the general fligtit behavior within the negative effective-dihedral range is primarily Influenced by the spiral stability. The m.otlons of the m.odel with a geometric dihj.edral angle of -20°, with tails off, and at'' lift coefficients of l.Ii and 1.8 apoeared to be directional divergences. Immediptely after taking off, the model commenced a diver- gence in yaw that was f ollov;ed by rapid rolling in the op^oosite direction caused by the negative dihedral. No recoveries from the Initial divergence could be obtained. NACA AR^ Fo. L?J02 13 Effect cf Lift Coefficient The flight ratings of figure 8 show that increasing the lift coefficient from 1.0 to 1.3 at constant values of Cy and Cv, had a slightlv detrimental effect on i.p n^ the general flight behsvioi' of the model over bhe negative ef feet iv3- dihedral range. This detrirr'.ental effect is believed to be caused by the increase in the rate of spiral divergence indicated by the calculated lines of constant damping shown in figure 3. CO INCLUSIONS The follov/ing conclusions were drawn from free-flight- tunnel tests to determine the effect of negative dihedral on the Iscersl stability end control characteristics of a free-flying dynamic model at high lift coefficients: 1. As the effective dihedral was decreased from 0° to -15°j the model became incressingly difficult to fly. With en effective dihedral cf -15° tlj.e flying character- istics were considered to be dangerous because, vi/hen there vjas only a slight lag in the application of corrective control following a disturbance j the unstable m.om.ents resulting from spiral instability became sufficiently large to cver':"vOwer the mioments of the controls so that return to straight flight v.ss impossible. Inasmiuch as full-scale airplanes because of their greater size will diverge at a slovrer rate than f res-flight-tunnel m.odels, .the amount of negative effective dihedral that would constitute a dangsroLis conci.ition is expected to be greater for full-scale airplanes. 2. In addition to reducing the amount of sideslipping over the range of dihedral angles tested, increasing the directional stability wps found to x^euuce the spxral sta- bility for positive effective alheirel s.ngies aiid bo increase the spiral stability for negative effective dihedral angles.. The net result of ^rcreaping directional stability, however, was to improve the general flight behavior o\'er the entire dihedral range. 5- In the negative effective-dihedral range, increasing the lift coefficient from 1.0 to 1.8 had a slightly li+ . FACA A:=l1 I^tc. L5J02 detrlr.ents.l efTect upon the general flls;ht behavior of the model st any given dlrsctiongl stability. the model st any given value of effedtive dihedrsl and Langley Meirox^ial Aeronautical Leboi^atory i-Tstional Advisory G oninii 1 1 s e for Aeronautics Langley Field, Va. NAG A ARH To. L5J02 15 REFERENCES 1. Gainpbe?Ll, John i-' . , and Seacorcl, Cbsrles L. , Jr.: The Errect of Mr.as Distribution on the Laterel Stf.bllity and Control Characteristics of an Airplane as Determined by Tests of a Model in the Free-Flight Tmmel. NACA ARR So. 3K31, 19^5- 2. Zimrr'.srr-an, Charles H. : An Analysis of Leteral Stability in Fower-Off Flight with Charts for Use in Design. NACA Re^-T. No. 589, 19 37. 3. Shortal, Joseph A., and Osterhout, Clayton J.: Pre-, lir.iinary Stability and Control Tests in the NACA Free-Fllpht Wind Tunnel and Correlation with Full- Sea Is Flight Tests. NACA TN No. 8IC, 19lil. I|-. Short f-.i, Joserih A., and Draper, John »7. : Fr ee-P' light - Tunnel Investigation of the Effect of the Fuselage Length and tiie Aspect Ratio and Sise of the Vertical Tail on Lateral Stability end Control. NACA ARR No. 3D17, 19^13. 5. Canpbell, John P., and Seaccrd, Charles L. , Jr.: Effect of 'v'Vlng Loading and Altitude on Lateral Stability and Control Characteristics of an Airplane as Deter- mined by Tests of a Model in the Free-Plight Tunnel. NACA ARR No. 5F25, 19^5- 6. Bryant, L. W., and pugsley, A. G.: The Lateral Sta- bility of Highly Loaded Aeroplanes. R. & IVI. No. l8Ii-0, British A.R.G./ 193S. 7. Caiivobell, John P., and Llathev/s , V/ard C: Experimental Deterrr.inaticn of the Yav/lng Lioriient Due to Yav^ing Contributed by the \i,'ing. Fuselage, and Vertical Tail of a Midwing Airrilane Model. NACA ARR No. 3F28, 191:3. 8. Pearson, Henry A., and Jones, Robert T. : Theoretical Stability and Control Characteristics of wings v;ith Various Amounts of Taper and Twist. NACA Rep. No. 635, 1933. 9. Baniber, Nillard J.: Effect of Soire Present-Day Airplane Design Trends on Requirements for Lateral Stability. NACA'tn No. 814, I9I+I. NACA ARR No. L5J02 16 TABLE I.- STABILITY DERIVATIVES OP MODEL USED IN CALCULATIONS [Values were arbitrarily assigned to '^n^t ^h® independent variable; L( kz/b = 0.2k5] Cj was used as the dependent variable, ji = 8.12; ^xA^ - 0.165; (1) (1) 'h ^"P ^Ir Cnr Y (deg) Cl = 1.0 -a»i02 -0.14-9 -0.060 0.21*6 -0.040 -11.6 -.Ilk -.123 .005 -.49 -.058 .21*8 -.048 -li.6 .010 -.I4.9 -.056 .250 -.055 -11.6 -.166 .025 -.U9 -.050 -.oI*o .255 -.078 -11.6 -.250 .050 -.1*9 .265 -.115 -11.6 -'29h. .075 -.1*9 -.031 -.153 -11.6 ''.ll(y .100 -.1+9 -.021 -.190 -11.6 .150 -.1+9 -.002 .505 -.265 -11.6 -.611* .200 -.^9 .015 .320 -.540 -.415 -11.6 -.S70 .250 -.^9 .0^2 .oI*8 .537 -11.6 .500 -.1*9 .553 -.491 -11.6 Cl = 1.J+ ..0.108 -0.1*9 -0.086 0.51*0 -0.040 -11.6 -.121 .005 -.1*9 -.085 -.081* .342 -.048 -11.6 -.155 .010 -.1*9 .31*3 -.055 -11.6 -.175 .025 -.^9 -.080 .347 -,078 -11.6 -.214.2 .050 -.49 -.073 -.067 .354 -.115 -11.6 -.508 .075 -.^9 .560 -.155 -11.6 -.375 .100 -.1*9 -.060 .567 -.190 -11.6 .150 -.1*9 -.01+7 -.056 .580 -.265 -11.6 -!6i^2 .200 -.^9 .592 .1*02 -.540 -.413 -11.6 -.775 .250 -.1*9 -.025 -11.6 -.909 .500 -.1*9 -.015 .1*12 -.491 -11.6 Cl=i.8 -0.11k -.128 -0.1*9 -O.lll* 0.1+36 -0.040 -15.5 .005 -.1*9 -.115 .1*56 -.048 -13.5 -.1)]? -.1814- .010 -.49 -.112 .437 -.055 -15.5 .025 -.1*9 -.110 .1*59 .1*45 -.078 -13.5 -.25U .050 -.49 -.106 -.115 -15.5 -.522 .075 -.1*9 -.103 .446 -.155 -13.5 -.392 .100 -.1*9 -.099 .450 -.190 -13.5 -.532 .150 -.1*9 -.092 .457 -.265 -13.5 -.670 .200 -.49 -.085 .463 -.340 -13.5 -.810 .250 -.1*9 -.082 .468 -.413 -13.5 -.958 .500 -.k9 -.078 .471 -.491 -13.5 p is measured in radians. NATIONAL ADVISORY COMMITTEE FOR AERONAUTICS Fig. NACA ARR No. L5J02 Tails Sand 6 '(£nd pla+es") Tail 4 Tail 3 — Tail 2 Tail I NATIONAL ADVISORY COMMITTEE FOB AERONAUTICS f/yc/re I. - Threz-view sketch of model tested /n Langley free.- flighf funnel showing range of dihedral odjusrment and alternate vertical-tail arrangements. NACA ARR No. L5J02 Fig. 2 u «3 •H b3 ■1-3 I rH u •H 4-3 U > 0) O E Cm o cd (■J bo C 5 tw 0) o •H c c o l-i (m a. Li O Q> to +3 (-1 a 3 cr 1 ■ 3 -H d-i i^ O lO 1— 1 1 t • (.-4 •-i O (U c 0) c iH 3 bo +J C (d *3 x; M tlD ca •H ij rH t3 Cm 0) 1 SZ 5 •H (U s r-H QD •» C iH cd q; J •t3 o s 1 • LO OJ S-i :3 bo NACA ARR No. L5J02 Fig. 6 8 Q to ^ ^^ :^ s> 1^ !2^ Q V? 8^ SI Q^o^ 8^1 o !^ 6sp J5>Cf ' '^ 'jspUJCUOCf /^///fqD/£'-/DUO//9A//(/ § en Fig. NACA ARR No. L5J02 .006 oyi- .ocz o -QQl ¥^J^y ^/:' UAtrp/arte A OAfrplctne. B _^ L -/x>f -.ooz o ,ooa ^oo^ Effecfii^e -d/AedroJ /XLTCUDe/eTj -C, ^ per deg NATIONAL ADVISORY COMMITTEE FOfi AERONAUTICS f/gure 7 .- VaJues of 6) ond Cq^ ^ Mo modern h/gh-poy^erSd cjurjo/ones as compared wif/7 the range fesied. NACA ARR No. L5J02 Fig. 8 t I ° 8 UNIVERSITY OF FLORIDA 3 1262 08104 964 4 UNIVERSHY OF FLORIDA DOCUMENTS DEPARTMENT !20 MARSTON SCIENCE UBRARY P.O. BOX 11 7011 GAfN^SVfLLE. FL 32611-7011 USA