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Produced by the NASA Center for Aerospace Information (CASI) MR No. I.6F25 . 1' I FILE NJ.TIO AL ADVIS' c~e FYAEBJJNAUTICS
• I
DBE AODR ED
MEMORANDUY REPORT f ~. S1 'i; T, . . ·, FO AE O Aur, ~~r'N1£"lt"1'2S;,-' D', • 'hA for the 1 J lo Qf.;t~Ol '.) \ ec \o H' ~ e 'J Ctars if,(" t> Air Materiel Command, Army Air Forces 0 ~ Le,._ \2.(, r e,uvikl TF.STS OF A 1/S-SCALE MODEL OF THE REPUBLIC . ~ Le..\-W c~u J . XP-84 AIRPLANE (ARMY PROJECT MX-$78) IN THE (sco 0 /\cl \C()~{ ~ 'f"u/\.L I~ > .... r u... '1 rro~ -r , v" u LAWLEY 300 MPH 7- BY 10-Foor TUNNEL S:. n By Warren A.. Tucker a:rxi Kenneth W. Goodson Langley Memorial Aeronautical Laboratory Iangley Field, Va.
July 17, 1946
------·--·------·-- • ..11'11...... :.------~-- --~ ,;
HAGA LANGLEY :i.rnMOR I AL AERONA.Ul'ICAL LABORAmORY
MEMORANDU1v1 REPOHT for the?t •- ~~r.~b\f~([) .~ Air i~ateriel Command , Army .air Forces
RESTRICTED ),LR No. L6F25
TESTS OF A 1/5 - SCALE f1:0DEL OF THE REPUBLIC
XP- 84 AIRPLANE ( APJ,IY PRO.:fECT MX- 5 78) IN THE
LAi'TGLEY 30) If.PH '? - BY 10-:,FOO'r TUNNEL
By ·.: arren A. Tucker and Kenne th VI . Goodson
sm,IMP.RY
A 1/ 5- scale n,odel o.f the Republic XP- 84 .airplane ( Army Proj 3Ct MX- 578) was tested in the Langley 300 :MPH 7- by 10- foot tunnel . The primary object of the tests was twofold: to determine_ a practicable met~.od of increasing the longitudinal stability in the landing confizuration, and to investigate the effects on longi tudinal and lateral stability of various external stores (fuel tanks , bombs, and rockets) . The effects of the fuselage dive brakes were also determined, and the critical Mach numbers of certain of the airplane com ponent s were estimated . The use of the revised horizontal tail (of larger aspect ratio and area than the original) seemed to be the most feasible expedient for materially increasing the longitudinal stability in the landing configuration. The neutral- point shifts produced by the various external stores were unstable , the largest shift being ~ about 2 . 5 percent mean aerodynamic chord . No appreciable aerodynamic trim changes were caused by the external stores . From the standpoint of range , maxL~um speed, and rate of climb, the advantages of mounting the fuel tanks at the wing tips rather than inboard beneath the wings were clearly demonstrated by the tests .
a ';)§§ mRICTFD MR No . L6F25
The effective dihedral parruneter Ci was the only ·, . . ". wI static lateral- stability derivative ·appreciably affected by the external stores . At high lift coefficients, the tip mounted tanks caused a larf_!;e increase in the effective dihedral parameter (about 4° increase at a lift coeffi cient of 1 . 0) . This increase was held undesirable , because the tendency- toward oscillatory instability that it would cause would be heightened by the increased mome_nts of inertia resulting from the weight of the tanks when carrying fuel .
- The fuselage dive" brakes, when ,_ deflected, caused a change in tri~ tending to nose the airplane up; the neutral point also moved rearw_ard upon.. deflecting the dive brakes . The amount of elevator required to over come · the change ·in trim was well ·within the availabl e range of deflection . It was estimated . that a dive brake deflection of 90° would .dE;lcrease the terminal Mach number in a vertical dive by about 0 . 1 .
The estimated cri-tical Mach munber of the V- front canopy was about 0 . 04 greater than that of the original canopy . Pressure - distribution tests disclosed severe pressure peaks i -nside the nose of the jet entra.'1ce duct . The.se peaks, which would lead _to separation ,and conseq_uentiy poor ·pressure, recovery at_, the engine, could . be reduced by_· .using a smaller nose ,radius and.. a modified ·· internal lip shape.
INTRODUCTION
At the r·equest of the A,ir _11ateriel . C6~~d, Army Air . Forces, a 1/5- scale r.10del of the Republic XP - 84 airpl·ane (Army · Project Mx~578) was tested in the Langley· 300 MPH 7.- by ~0- foot turmel. • Previous tes-ts of· the same model in the Larigley 7- b y 10- foot atmospheric tunnel (reference 1) had indicated 'that the longi.tudin.al stability was undesirably low , particularl-y in the landing corifigur:ation. One of .,,_ ._ the objects of the present invesl:;igati,on was therefore · ·, to determine some means of . incre-asing the lorigi tudinal stability in the landing configuration·. To this end, tests_ were made of various flap mcxiifications and also of _a revised horizontal tail .
2 . lIR No: L6F25
Tests were made to determine the effect of the various external stores (fuel tanks , bombs , and rockets) on the longitudinal and lateral stability characteristics . Tests were also made to determine the characteristics of the fuselage dive brakes .
Because of the high speeds expected to be attained in flight , pressure- distribution tests were made to determine the critical Mach nTu~bers of the original canopy and of a V- front canopy. Pressures were also measured inside and outside the nose of the jet entrance duct .
COEFFICIENTS AND SY1''1BOLS
The results of the tests are presented as standard NACA coefficients of forces and moments . Rolling- , yawing-, and pitching- moment coefficients are given about the center-of- gravi ty location shown in figure ·l (26 . l.~5 percent of the mean aerodynamic chard) . The dat a are referred to the stability axes , wl The coefficients and symbols are defined as follows : CL lift coefficient (Lift/qS) c:'.) drag coefficient (Drag/qS) ex longitudinal-force coefficient (X/qS) Cy lateral-force coefficient (Y/qs) c rolling- moment coefficient (L/qSb) 1 Cm pitching- moment coef f~cient ( '·i/qSc 1 ) C yawing- r-1omerr t coefficient ( .. :/qSb) 11 3 I\1R No • .L6F25 T I effective thrust coeff·icient based on wing C area (Te/qS) p ,pres su~e coefficie•nt p ~c\ -' ( q / - Lift· =, -:z 0 Drag= - X (only at ~ = o ) forces along axes, pounds moments about axes, _ pound -feet effective thrust , :pomds p J.ocal static pres.sure ) polmds per square fo:Ot .free·- stream static .pres Sl\i"e , pol·.nd s_· per . square foot • q · free-stream dynami-c ,nressl~re , p_9unds per square foot (pv2/2) · .· · · · S wing area (10 .40 sq ft on ''!:-:. odel) c' wing mean aerod;:,rnamic chord O~ b VJing spaµ (-7 . 28 ft on model) h ·distance from thrust l?.ne to cente_r of gravity, positive when thrust line is above center of gravity ( - 0 . 0165 ft _on model) A .area of duct inlet (0 . 0872 sq .t:t on model·) 7, distance from duct inlet to center of gravity (2.97 ft on model) V free - stream air velocity, feet per second average air velocity at minimum cross section of duct inlet , feet per second 4 MR No . L6F25 p mass density of air, slug per ·cubic foot a a."'1.gle of -attack of fuselage reference lh1e , degrees angle of yaw , degrees angle of stabilizer with respect to f uselage reference line , degrees; positive ·when trailin6 edge is down elevator deflection with respect to stabilizer chord line , degrees; p0sitive when trail ing edge is down CL slope of lift cur ve , per degr ee a neutral-point location, percant wing rr£a:1 aero dynamic chord ( 0cnter-of- gria.vity J.0cation for neutral longitudinal stc..bi·li ty in trim!:1ed f l ight ) l{ radius of gyration about X- axis , feet X k radiu·s of gyration about feet z Z- axis , µ relative density factor (m/pSb ) m mass of airplane, slugs Subscript : denotes partial derivative of a .coefficient with respect to a..vigle of yaw \example : C1,.1, = oc 1 /ot) AIRPLA!IE, ~,IOD.EL, Al:D APP A.RATUS 'Ihe He public x:.)-84. airi::la11e is a single- place , single- jet, low- midHir:g fii(hter, with tricycle landing gear . The jet ~ower plant of the airplane is completely enclosed ;;i thin the fuselage , vii.th the intake duct in the fuselage nose and the jet exit at the tail. The airplane has been designed to carry ~uxiliary fuel tanks , bombs, rockets , or a combination of tr.ese external stores, 5 MR No . L6F25 depeading up·on the tactical use of the airplane ( long range fighter , fighter-bomber , e tc . ) . 'I1he .airplane physical characteristics as supplied by the manufacturer are presented in table I . : The _model, which has been. tested previously in the Langley 7- ·b"y 10- foot_ atmospheric- tunne 1 , was supplied by the Republic Aviation Corporatior. . A three- view , ·:c;irawing of the 1/5- scale model with the original horizontal tail and a photog!'aph of the model in the landing con figuration (split flaps deflected 60°) mounted in the Langley 300 MPH 7- by 10- foot· tunnel arE? shown in. · figures 1 and 3, respectively~ The model was equipped with a ~-0 - perc~nt- span sl,otted flap , the chord of which . vari~d _from 24.9 percent of the wing chord at the inboard end to 26 . 6 percent of the wing chord at .the . outboard ·' end·: The :f;Lap posi ti.on when. deflected ·30° is ..shown in fi6ure 4. Provi~ions w(:;re also made for testing with a 1~0-percent- span split flap having a constant percentage chord of 25 percent of the , ~,ving chord . The revised horizontal· ta.il, which was formed by adding area -at the root section of t he original . tail (thereby increasing the · span) , is comp1;1 red in figure 5 with the original tail.. It will be noted that the revision did not affect the dimensions of the elevator . Drm•lings of the fuel tanks· in the-. two positions tested are shown in figures 6 and 7. A photograph of the fuel tanks mounted in the tip position is shown in figure.. 8 . The bombs we.re also located in tvvo' positions . ( See fig . · 9.• ) . The rockets were located under the fuselage as shown in figure 10 . The fuselage dive brakes are shown in figure lt.. .. ' The locations of the pressure orifices are shown in figure ·12 . When ..the pressu1·e orifices were being installed in the nose , it was n0ticed that a template made .. from the dimensions given in Republic drawings SK- 30,- 1. and SK- 30- 7 was no.t a good fit with the actual nose . A comparison of: the. aotu~l nose with the design nose is given in figure 13 . Photographs of .tl-e · original and the V- front canopies are given in •figures 14· 8Tld 15,; The model was tested in the ·cruising configuration (landing gear and flaps retracted) and the landing con figuration (landing gear and flaps extended) . 6 11R No. L6F25 The model was equipped with a sin0 le-:-stage axial flow blower driven by an electric. motor . This unit, located within the fuselage, produced a cold jet Bhich was used tu simulate the airplane jet for the pressure distribution tests. Because the inlet velocity could not conveniently be measured directly, the average velocity was nieasured at the jet exit and converted to average inlet velocity by usin~ contLnuity considerations . The exit velocity was measured by a single pitot- static tube so located as to r:ieasure the average velocity at the jet exit; the location of the tube was obtained from a series of preliminary, test~ , in the·· Langley 7- by. lD- foot tunnel . TESTS ASD ~ESULTS Test Conditions The :tlap modification tests were, made at a dynamic pres sure _chosen to give a Reynolds number equal to the effective- Reynolds number of the tests made in the La:.igley 7- by 1O-foot atmospheric tunnel . The remainder of the tests were made a:t dynamic ::.: :• ::- s s ures c:.::- ncitionec. mainly by the strength of the model components . The values of dynamic pressure , Reynolds nu::nber , and Mach nwnber for each group of tests are listed below . q Tests R M (lb/sq ft) 6 Flap modifications 41 .8 1.JG x 10 O. lJ Dive brakes , rocket drag 110. 0 2. J . 2 Pressure distributions 27 .9 1 . 4 • 14 ,...11 o~hers 55 .6 I 2 . 04 . 20 i I Corrections · Because of t he limited time availc,ble for the tests, the tares ce.used by the model support- strut system were not determined. Because a large rn... 11i1".Jer of the tests v1ere made for c on~-2ri::01~s with each other, the m:-iission of' tares is not too important. Jet- bouncary corrections have been ap~lied to the angles of attack, the longitudinal force· coefficients , 7 MR No . L6F25 -and the .tail- on pi tching- mome'nt co.ef.:t;'icients . The fallowing c orrectic:Ls , obtaii~ed from . reference· 2, were added to the test data: t:,a = 1.oocL where 6a is in degrees . Because all the model tests, with the. e~ception of the pressure- distribution tests , were .. :tnade ; po.wer-off (model, blower u:;i_i t inoperative), the · variations with CL of a~rplane Tei and vi/v were not duplicated . There .fore ,. whenever pitching- mome nt data were desi·red for the idling-power condition, it was necessary to c~rrect for · ~h~ ~-ffec. t of Tc·' .. a.J.?rl . V1 /v. · The- correct ion for the direct thr-qst moment is given by where T~' : is for the .. _ig.J,..i;ng--.y:,ower ·- cond.i ti'()h . The varii-ation- of ·· ·T; ' ·· ·with CL for the idling- power condi - tion of -the airplane is given in figure 16 . These data were supplied by the Republic Corporation . The correction fo:e the turning of the air at the nose ~s given by ...V-~ 2AL '·· ·· . . ~- 6C. =. 6 Vi -- shi a :::; G. 000568 6. 2.Vv a 0 · m ( Sc.' · V · ,· . . : v. where 6. 2. is the difference .in in1et-veloci ty ratio V be tween the mod,e 1 and the °id.ling-povi~r condition of the airplane . (See fig. 17 . ) The data of fi6ure 17 were supplied by the Rep~blic Corporation. Both tnese correc tions, which have been derived in reference 1, were added to the power- off data . The combined correction was 8 Mrt No . L6F25 destabilizing but small , causing a forward shift of the neutral poi~t always less than 1 percent mean aerodynamic chord . Test Procedure Except for the pressure"distrib~tion tests , all t ests were · made power'...off (model blower· unit - inoperative) . For those cases in which it was desirable to have pitching mqment data for the idling- power conditi,on, thus allowing a more. direct comparison with po~~r- on data from the L~gley 7- by 10- foot tunnel, the power- off pitching- ·moment data were corrected to the idling:..power condition by the methods previously explained . In ..making the·- pressure- dis'tribution tests , a dif ferent procedure was necessary, Since the ·distribution of pressure , particularlj over the nos~ of the entrance duct, depends on the inlet- velocity ra.tio . · .. Therefore , the var-iation of airplane inlet- veloci~y ratio with lift coefficient (~ee fig . 17) was duplicated fo~ the pressure distribution tests . The t r im- lift curve used in making the tests is ·shown in figure· 18 . This cur ve ·was obtai ned from the test d·ata. For a sel ecteo. angle of att ack of the model, the trim lift coefficient read from. figure 18 was used to determine the corresponding inlet- velocity _ratio from the appropriate curve of figure 17 . This inlet-velocity ratio was then obtained by suitable opera tion of the blower unit • .An expla..nation of figure 17 will prove helpful in evaluating the data . The two curves of figure 17 were supplied by the Republic Corporation . The curve marked "power coridi-tion A" was given as the variation of Vi/V 'with -CL .'for idling power (80 percent rpm) at sea level and· t :._e cu.rye marked "power condition B" was given as the · variation for full power (100 percent rpm) at sea level. Later calculations at the Laboratory disclosed that the curve labeled power condition A al.so closely represented the variation of Vi/v wi.th CL for full power at 3.0,90.0 feet (at any CL, the calculated value of Vi/v for. f,ull powe~ .at. 3.0, _000 feet is about 0.1 less than the value· for idlir1;g _power at sea level) . Three pmver cor1ditions were thus sfmulated in the tests: full power at sea level, approximately ful l power at 30, 000 feet, and idli~g power at sea level . 9 MR No. L6F25 There is one further point of interest regarding the curves of figure 17 . The data from the compa:r..y a pparently were worked out neglecting .compressibility effects . Had the effect of compressibility been taken into account , the inlet- velocity ratio for power condition Bat ~L ,= 0 . 5 -wqu-ld have been a'Qout 0 ; 15 less (a:.t higher values of · CL, the dif-fe-ren·ce bec"o111es smaller) • . The use of the incompressible curves in estimatlng the critical Mach number of the outer part of the nose of the entrance duct is therefore slightl y unconservative. _. The lateral st.ab.:i,lity dei-•ivatives at .small angles ' [ . ..of yaw were ob.t,ained from t~_sts through the angle.- of a tt_ack range _at angles of· yaw of .±5° by assum;ing .: a straigh_t..:lipe variation. ·1?etw~en·.t11.e ;se· -po-in ts·. . . : Bec,a1J,Se mµch o:' the .. program .invoive.d the- cfotermina tion of groups of relatively sm.iili . incre-niental . effects , the ·tests of the cl.ean model ·were repeated for each group, thereby assuring that an·y small changes· in the clean model •condition _would not . introduce. errors into the determination of ' the -increm~n-tis •- ',, ' ., ,, • •. • •• t .. ,; - ... : . ~- \ , .... ,., { Presentation of Re~ults _ An outline of tlle -.figures' .pre_s~nt.i~g the .-1:~·sults is given below: ... ,· -· •·, !" Figure A- . Fla,p 111odific.atio~s .an~r revis.ed tail : ' - ·stabil'iz~r tests , .· or.ig'ina-1· tail • .•••. ·.:'. .: •• 19 Stabili zer tests, -· revised ,' tail . ~ ' . • . • " .• 20 Elevator tests , revrsed 'ta'il • • • •.•• 21 .. - Neutrai points for flap m,odifications . • • 22 · :· . lfoutr_al ._points ~or origi_Dal and .revised t.ails • 23 B . Lo~g.itu.dinal· stability -w.i~h ;external stores. on wing :· · - _, StaoJ1i'zer· tests· ~- .- ~- ~ .: ; · • . • • . . • • . • 2~ Neutral points • . • • ~- . - / ~ · ••••••• ,• • 25 '. " . 10 . : ~- MR No. L6F25 C . Lateral stability with external sto::-·es o~ wing: Lateral s ta'.Jili ty deri va ti ves at sm2::!.l angles of yaw ...... • ...... ,. . . ' 26 Stability bounda::--ie s • • • • • • • • .• 27 I'e c ts throl,fs h y&.:'11 range : ILb oard tanks .. ~ ...... •• • • 28 Tip l,ank·.:; . , , • ~ . . ~ ...... 29 ~ - . . . Tan':G3 al~ 'J. 11o .c.1b .3 • e • e a a 4 a a $ • ~ a V 30 D • . Rockets: 3tabi liZe r t ~/B I: ,3 • • • • p• • .·-·. • • • • • • • 31 ,.. .Ef feet of r e ...... ~ t.c t ~ . • • ,_ . . -- • . . . . . • 32 . :Keu~ral point s . • · • • • • • • • • • .. • • • • 33 E. Fuselage dive .. brakes: Stabilizer tests •• ...... 34 Terminal Mach numbers ...... ;;, ...... 35 F. Pressure distributions: Original canopy • • • • ., • • • • • • • • • • 36 V-front canopy • • • • • • • • • • • • • • • • Nose of entrance duct ••••••••• •• §~ Critical Mach number of canopies • • • • • • • 39 Cri tictal .Mach number of nose • • • • • . • • • • 40 prscus sroN Effect of flap modiTications .- The flap modifications (:30° slotted flaps wlth ""-iL.: ro:is · 2.r•o opo. i5?, and 60° split flaps) were tested with an eye tc improving the stability ·over that v1ith the 30° slotted flaps, YJithout imposing too severe a penalty on ~~e maximum lift coefficient obtainable . As shown by the stick- fixed neutral points of figure 22, the incorporation of 15° aileron droop actually decreased the stability over the range of lift coefficient in which the flans ·;lould be deflected . Below a lift coefficient of 1.25, the stability with 60° split flaps is slightly greater (1 or 2 percent mean aerodynamic chord neutral point) than t h at with 30° slotted flaps , but above CL= 1 . 25 the stability with the split flaps is less. The results 0£ reference 1 indicate that the stability with 60° split flaps will be greater over the ent~re lift range . 11 r- m No . L6F25 The values of trim Cr for the various fl~P · '17la.x configurations were obtained from fig11.re 19, and are tabulated below . Because of the low Reynolds number of _.. the- tests, the ·. absolute values of Cr. are doubtless "Jlla.x not those that will ~e dbiained on the full-scale airplane . Trim Flap·configuration . ' Cr .. ·-':max · 30° slotted flaps . 1 . 53 30° slotted flap_s, _15.0 ai·le·~op. droop 1. 69 60° ~plit flap~~ . _1.46 . ' . Henc·e; if it is decided to ut3e . split. flaps on· the basls of the test results.from. the Langley 7- by 10- f'oot tunnel, the d~crease ~n ·. CT..rn • will b~ o~-ily· ·about 0 . 07 . , . . , . . ax . . Split· fl.ap.s ·wou:i'd also pre sent a s~mpl~T cons tru'ctioh •. problem . E.ffe..c tJ. (jf ·revi,s~ 'ho'riz~n;Gl :tail.·:-. Tne increase in st?-bili t:7 afF°oro.ed, b'.'f. the - rev;lsed . h:or.i.zontal tail is illustrated-in figure•25, in .which the stick-fixed neutral points ·of .t:ie ·mode.l ,wi-th -che revised tail are compared with those. . f.or· the mode 1 with the orig:inal tail . Calcula tions bad indicatAd that the revised tail should give a 5 percent favorable neutral- paint shift at low. 1 ift. .,,. coefficients , with the model in the. cruJsi}'.lg. eonf'igura tion; the neutral points of f!gu.-_re ... 2•3'· ·s·how a shift of . about 6 perc~nt, which is consi'dered· g.ood' agrP-ement . SJn:ee the revised·'tail. was ·. derived from the ~riginal tail by adding .fixe¢i area. wi tnou.t · increasing the amount of movable · ~rea (.~ee fig . 5), .. i 't was .considered advis·abJ_e to determine the ·elevator effectiveness o·f tb.e revised tail . From the data of.. figure 21, the ·average· e.levator effectiveness ooe/6Cli was determined; .the_ values·. · obtained are compared :below with ·the corresponding values for the or;tginal _tail • . ~he . values of ?5 6 7cCL· for the original tail were oqtained from reference 1, since no · elevator ·tests with the original tail were made in the .Langley 300 MPH 7- :by 10-foot turu)el .. 12 MR No. L6F25 Average 'ooe/oCL :{oriz ontal tail Cruising Landing configuration configura ti'on (60° split flaps) -- Original . a (reference 1) -4,.51 -5.99 -- - Revised · -7,.75 - -. · -7 .89_ - - ·• - aEstimatej_ from :i_'solated tail t e sts· and, stabilizer te,sfs -· on complete mod~!~ .. l These values i:::-.Ldica,te that tc:i ex(scute a given . maneuver, a grea.-ter change in elevator deflec,tiop will ·. _' be required with . the fevised tail. · Effect of _fuel tanks and bombs on longi ti.idi:nal stability and drag foriginal horizontaltaill.- An ·• insp~ctior1; of -the stabilizer curves of figure 24 reveals t h at for a given center-of-gravity location, the trim . changes . caused by the various ·ruel tank' ancl. bqmb c·on- · figurations are negligible. This is of interest .· ~i-nce, it indicates that u.pon drq_pp::Lng the bombs;- .fq_r e.xarnple, the onty trim changes which must be overcome by the pilot will be those caused by any ·c~nter-of-gravi ty shift occurring when the bombs are re1e·ased •. · The neutral ... point shif't caused by the various fuel tank and :bomb configurations is in general slightly unstable, the maximum unstable shift being about. 2.5 percent mean aerodynamic chord. (See fig. 25.·) Any actual change in static margin will depend on any possible changes in center-of-gravity loeation caused by the presence of the external stores. To a id in evaluating the relative merits of ·the different· configurations, p}:3.r·ticularly from -the stand point of their effect oh the range of the aircraft, certain quantities obtained from enlarged- scale 'plots of the data of figure 24, for a stabilizer setting of -1.0°, are presented in the following table. In obtainine: the test data, no atte:71.pt was made t0 fix boundary-layer transition on either the stores or the wing; some preliminar,y tests indicated that on t h e fuel tanks transition occurred very near th~ nose. 13 \ ·.· ' Exterqal stores - ---'---_;_ -~ ____ _.:..;.__.j.~o_,-----4------+------+--~--+---- None ·12.3 0 .. 57- 0. 0463 0.021.io O. 07.9 Rig:1.t inbo ·ard tan k ll.7' . 62 .0530 .02 82 , . .076 Both inboard tanks 11.2 J;1 ' .Dc:Lt-4 . 0302 ..075 Right tip tank · 12.3 ·- . ·. .58 .0472 .0251 .080 Both ·t:;ip tanks · 12. 9 _ 8 -•i 1 . • 5. '. j .04 50 -~252 • 988 Both tip tanks+ ieft • l ; • inb .oard bomb . - 11,8 ';, .0526 ..0288 .086 Two tip bomb s . +. left , _\L .D, 8 ., , ·. . ' inboard bomb ,! ,-· .0601 .0325 ,.079 ' ' .. ""! '"''. ... ' Jm inSPf-?•t,ion ' ·of -the . v~iu e s of. t CL/en )~ai indicates that for a negl -igiple wei t;ht j)i-c;re~se (ts:rks e·mpfy} t h e ·t:i.p-moun't~q.,•·iank~ i'{o,uld gi ve a 5:..percent increase ··in ·1\u1ge ove.r t,he airplane wi t,h . no fuel tanlt.s, where as the inboard. mounted ta1;1~c~ -would : q.ecrea .s~ ·the _range about ·· 9 ;Percent ·.: The yal ue s of ?,l;..·ag coefficie 'nt at ..:cL . := 0 . l, qti.ali -tati vely' illus ,tra te the less drasti _c ·reduction . imposed on the ,max.~m.um l evel-;-flight speed by the tip-m.oim _ted tanks, as : c·ompared to the ' iriboard-' .tank installation~ Calcµla• tioris il)dica .ted . that :the tip-mounted tankS: wo1.U-d decrease the • t(?p spee9- about 10 miles per hour ·, "Yhe·reas the iJ.lbgard-mounted tanks would _.gi -ire a.- · ----· -· reduct:tcm of about 5p The same calculations also indicated that the maximum rate of climb was not affected by the tip tanks, whereas the inboard tank installation appeared to decrease the maximum rate of climb by about 200 feet per minute . These figures should not be interpreted as quantitative perfor~ance estimations, but as indications of the relative merits of the two tank installations • . . Effect of fuel tanks . and bombs on lateral stability. ·Only small e~f7c ts- or:i. . the ~arame~e~s · 9n:'1,r and Cy'V are shown by the plots against CL of the lateral- stability derivatives C, , ·en , and Cv . at : small angles of ' ~ I, \JI . 'i' . ~'V- . , yaw (fig. 26), which prov~de ap over- all picture of the · effects of the various fuel. tank and b9mb cdnfig-ura.tions . Th,~ only derivative affec~ed _to O...YlY. r.1arked degi~ee is Ci,, '/ the . ef.fecti ve-d.ihedral parameter • . :·The . effect of the inboa'.rd tanks on this parameter ·is small, ·· but the effect of the tip- mounted tanks , either alone dr·in · conjunction . with a single inboard bomb , is to -increase- the positive · value ·of C7, '41 · by an amount proportional. to.. ..the ' lift ·coefficient~ However, with ' two tip bombs and a single inboard bomb , the parameter Ct is ·reduced by a \)I practically constant amount over the lift range. · It was considered desirable to invest'igate the · dynamic lateral s t ability characteristics of the airplane when the tip tanks are carrying fuel, because in this •· condition the high moments of inertia, co·mbined, with the increased Ci ~ would be expected to give a tendency \/I1 • . ' - toward undamped oscilJations. Accordingly, the equations of appendix I of referenc e 3 ~ere used to compute the .bound.arias fur s D:.r!}.l and oscillatory stab:!. li ty for leve 1 fli[ht ::3_t'20,000 · feet for, 11.ft r~oefflcients r>f 0~21,. and ~).~O . (See fig . 27 . ) . I:1. com.putL:· the bou!1daries , no uc,te11pt \·1'1s Y?1.ade to estir.3:at~ ·ilie. efiect of t}:... e wi:1.g . 'tru:1.lrn on the... d.w.~,p.:.ng derivati7e:::; it is thoc1.ght tlu!-t this effect w•-11ld be relativelJ '.3uall . The la1~;:;e sy.:1901s are the values ;;iven lJJ: tha tes'~ c.°.ata; th0 7ositl.on of t:1.one s':}~ --ols in relation to th'1 ixn2I1.d.aries :'..:..1dicate_ the type of stability or instabilit'y. · CT It will be noted that at .LJ = o.ao the test s-ymbol lies 1-n the region of' spiral ins tabi li ty . Flight ·. 15 MR No. L6F25 e~:per iencehas indicated that a moderate amount of spiral ir..stabili ty can be tolerat~d, and· has _, little bearing on the ability of the pile~ to fly t4e airplane efficiently. It is .greatly desi.re._d~ however, to have a high degree of_ damping of-the lateral -oscillati~ns. · The nearest appr.oach to oscillatory instability -occurs with the fulJ_ tanks at Ci, =· o.80, where the tyst point falls very near the oscilla~9ry boundary. The conditio!'). of level .:flight at CL == 0~B0 at .20,000_:f,'ee.t -~s ratner · extreme, so that it is unlikely I ; ...... ~ .. that · the- oscillations will become undamped for any flight condition. However, because the degree of damping of the , oscillations becomes smaller as the boundary is app:roached, · it may be ~hat in some cases the 6s.cillations will qe so ~Jghtly. damped as to become objactip~able to the pilot . It appears that the a.irpla:ne could have been de.signed· with 3° or 4° less geometric dihedral ( note that even in the three-bomb c~:mfig".Jration (fig~ 26(c)), Ch!J would still be positive)~ _ The slopes of the curves of c 1 , . en, and Cy plotted against ' \j; ·for two selected aJ1gles of attack (figse 28 to 30) agree both g_ualltatively and quantitatively witil the curves of -figure 26. In addi t~on, the curves of fi~ures 28 a~.d ~9 indica,te that at an angle of attac!-<: of, lj ._7°_ (CL , ~ 0 . 7) a single fuel tan_k. ·mounted on the right wing either inbo.ard or a.t the tip shifts the rolli_ng-mornent, c1-1r·je , : ·\;-he shift ·being positive for che inboard:· tank a:q.d negative for the·· tip . tank~ · Not shown in figures 28 a::id· 29 is the face that :a .s i ngle.· tanx, par-ti-eularly whfl~. full, will cause an appreciable lat·eral S•hift of' t he c'enter of gravity. ·_ Th~ importance of a lateral ce~t·e~- of- gravi~y shi~t has been shown 1:i ref3rence· ·4. I .n order to·· check u~e ability · .of. the controls to overc·ome the combined ef f:i c ts of the $.symmetric a e rodynamic forces e.nd the later8.l sr..ift of the center of gravity, the rudder deflection~ , 'aileron deflections, and sideslip angles. ·required .:'c:::- trim in a full- power wing-level climb ~t CL= 0 ~7 have been cal cula ted, l1.sing the contro_l-'effecti.:veness data of refer ence 5. In making the estimates, the asyr.n;.etry of the model was t ,aken into account by assuming tr,at at "IJ! = 0 with ·the tanks cff, the rolling and yawing moments should be zero . A gross weight of 13, 000 pounds ·( tanks off) was assumed; the weight of a s i ngle full tank wa·s assumed 16 ~ No. L6F25 . : to be 1300 pounds. (The tank capacity was estimated as about 200 gallons.) The :results are tabulated below: : I Rudder Total aileron qideslip angle (deg) (deg) (deg) .. Right tip tank ' ; ·- 'Tank· full · 10.4 left 8.5 left 2.8 right ' Tank empty 2.5 left 7.5 righ.t rig~t . i •.7 .. .I Right · inboard tank TaEk full b left 12 .4 . left 1:.4 right .. . 5·• Tank empty 0 2.7 · left ' . 0 . .. ,· .. The calculated values show that the control deflections required are well within th~ range . of the available deflecti9ns (±25° rudder, ±34° total· aileron). At lower speeds the deflections required will .probably be somewhat greater. Effect o.f rockets.- At low lift coef f.icients, the dr~g' increr.1ent contributed by the two rockets beneath the fuselage was only about 0 . 001., as shown by the longitudinal-force-coefficient , curves of figure 32. At lift coefficients greater than 0.4, no . drag increment due to the rockets could be detected.· The effects of the rockets on trim and neutrai point were negligible. (See figs . 32 and_33.) · Effect or' fu·seJ:-age dive brakes .- Exar:1ination of the pitching-moment data of figure 3~. indi~ates that deflec tion of the fuselage dive brakes causes a pitching moment change which tenrs to nose the airplane up. Because of the low location of the dive brakes, it might be stipposed that the.drag forces acting on them would give a diving m.or.i~nt~ Apparently, however, i:hen· the brakes are deflected, the flow over the wing and tail is changed in such a r.1anner as to ·g ive a net nose- up moment . , This change in trim. may not 'be ob jectiona.ble if the fuselage brakes are to be used only as a means of limiting the speed in a c.ive (at a lift coefficient of 0.1, the change in trim corresponding _to a dive brake deflection of 90° amounts to a change in elevator 17 MR No • L.6F25 def1ection of about 5°). If the no:;,e-up change in trim is,·mai.ntai:i:i~?- at hfgh Mach nun~bers, the ,dive brakes cquld be utilize·cr:as ·· a .di .ve__ recovery devi.ce. However, if the brakes· were· to b'e used. as ·fighte..r . brakes to· che-cl{ . the. speed of the aircraft When apn.roachirig• ·s:-·" •· .•.... t$.r_get, so as to 'ali-ow -'8.~ longer firing (time- before cont'iict must- .. be__ pr9ken; the cl1arige in --t;c.im.. resulting from 8:PPlicatio:p. of the prake-s- w-ouJ.d _p e_ most disturbing· ·to -th~ pilot, since it would thr-ow the line- of'·•·:fi-r.e .. off .. the target. · · --· .. 1 ' . - . -~ -• r -•••' • The t'ail-off· curve.s snow that,··at tb,e low lift coef .fl"ci-ents. that will be reached ·in dive-a, .. th.e :ta'il load for trim with .the -d ivi:f. bral{e.s deflected will be ... someWhat- .. ; .less than that · re~uired when·-:ct-i·e di:ve---br.akes are not used . •• • / ..... , .• • J The ~-tabilizer curves shmv that di v~-brake deflec_: tion is· accompanied by an increase in longitudinal stability. The increase amounts t .o. a. rearw.ard neutral.;. poih.t shi.ft of about 6 p€;lrcent mean ae·rodyhamic chorp . f9r the p0° deflection, and about 8 ,. percen_t meal?- aero dyriain.ic chord for the 90° cl~.:i:... Ioctibn •.': About one-half . the increase in each case seems to ·be the re:sult of a _shift of the aerodynamic cerit1fr of· the win,g- fliselage - comoination, , the other half being ca~sed .by a lower rate of change of downwash at the tail. ' ~,: ~-,.. .., ,..., . Because the· p:nimar.y· fu'nct.ion ~:r' -tf.e Tuselage dive ··brake.s is to ·1imit _the ·divfng ,speed, it· is d-esirable to . see ·what . speed redm~tion oan 'be '' ef·fected rby use _of the ·' brakes . As an indication · of the · effectiveness of the brakes, the terminal· Mach · numbers 1:11: ve-r.tical dives - have been estimated . The estims.tio·ns were made . usJng the data ·of fi[;iure 34 in conjunction wiith· _the method of reference b ., The .re s.ul ts, sh9w~ in figure 35, indicate that ··~ 90° ·d:Lve brake·- a.·eff'le·c•t.i-0:ri.. wj,J:l reduce the terminal Mach number by roughly O. 1 • .. The · addft'i:cma'J. -decrement in terminal Mach number resulting from -filling the spaces in. the 90° brakes is only about 0.01 . The relatively low scale at which tte test data Were obtained necessitates that the absolute values of . the terminal Mach n11.t"TI.ber be - : regarded with some ·caution. · Suosequent to the tests , inf'ormaticn was received from the Republic Cor-pora t;i.on ·that changes ip the size, shape, and locati'on .of tpe fuselage dive· br'ake·s were being considered . The data for the original dive brakes are included in this rep6rt fo~ possible aid in .future design. 18 MR No. L6F25 Pressures inside nose of inlet duct.- The data of figure 38 show that sever~ pressure peaks occur inside the nosB of the entrance duct. These peaks will be flattened somewhat at full-scale Mach numbers ( t!1e mode 1 tests were made at a Mach number, of, 0 .14) , but they will doubtless still be severe enough 'to cause internal separat-;_ on, with a consequent decrease ·in pressure recovery at the engi_ne. It is thought that a smaller radius {perl:aps half .the present .vaiue) and a c'hange in the lower lnner . lip · shape, bringing the ·liJ? stra1ght back for ,a short dis ·.. Critical· Mach numbers,- The pres sure-distribution In computing the critical, Ma.ch numbers of _the canopies, .it was noticed t hat _the effect of ~ewer was . too small to be detected. The ref ore, only one, cul''Ve for . each canop.y is shown on figure 39 . The re·sults i'ndicate · that . the ·critic.al ,Mach mmi.ber · of the V-front canopy is only s l:~ 6:C:.t l·y (about •J . 04) greater than -chat of . t -he origfnal canopy. If the airplane is assumed to reacn ·a Mach number of o.e -at· either altitude, t he critical .Mac}) number of either canopy will be exceeded at -this flight Mach number. Because of the relatively small variati9n of critica:l Maeh number w:t th lift coefficient, . the flight Mach :µumber at which the · critical Mach number of ~::Ltl':1.e r canopy .is reached does not vary greatly with altitude . · The estimated critical )\fach· numbers of ··the outside of the · upper nose of the ent"rance duct are pre'sented in figure 40 , toge·tµer with the flight r,fa.ch . number. It should. b.e no:ted.. -that the plots of _figure 38 do hot in every case .extend to the distance .fr.om the .nose at which the peak p;ress_µ_re pn the .outside. nose is: ;:-e'ached; :-:the, critical Mach n,umbers of the outsid~ _nose_ were estimated from separate plots of the data presented in figure 36~ The effect of newer is quite evident. At sea level; for example, as the pow~r is in~reased, at any lift coe·ffic.ient the: 'inlet-velocity _r ·a·tio. is :1,ncref:!.Sed so that corresponding-ly less -air is diverted to t::1.e · outside · of t.).-1e !lose and, the critical Mac):l nwnber is increased . If ·as before a maximum flight .Mach number' of 0.8 is assume·d,· the curve$ of ....figu.re 40 indicate'. that ·at _sea level or at altitude the critical Mach number of thE{ outer upper nose . is never rea9hed, for· ei'ther power con- dition represented. · · · Because of the :nosi t;ion of' the nose whe:e.l well, t::.-1e pres·sure measurements on- the lower part of the outer nose ·· did not extend ,far enough back to per:nit a comr,lete determination of the critical Mach number. However, the outer. lower :nose i~ less critical. than_ the outer upper nose for any positive. angl:-3 ·0f attack, so the omission is not- important. 20 • > MR No. L6F25 CONCLUSIONS ' . The following conclusions a:re _· ba~ed· on the results of tests of a 1/ 5-scale model of the Republic XP-84 air plane (Army Project MX -578) in the Langley 300 MPH · 7- by 10- foot tunnel : . . 1 . The subst.itution of split flaps for the original slotted f l aps afforded a stable neutral- point -shift of only 1 or 2 percent mean aerodynamic chord below• Cr= 1 . 25 . Above CL 7 ;1. . 25 . the stability with split ~ . flaps was less than· with-the original slotted f l ~ps ; • . The adoption of the-. revised.· horizontal ,:tail ( of great'er· aspect ratio and area than the. original') appeared the most feasible means of. r.1.aterial~y increasing the longi tudinal stability. .in the l.anding _aontiguration. 2 . The presence of the various external stores c auseA unstable neutral- point shifts , the largest shift being· abou.t 2 . 5 percent mean aeroo.yn;3.mi.c chord . Aero' dynamic trim changes caused b_y the . external stores were . negl1gible . · 3 . From the standpoint of rarige, maximum spe~d,. and rate cf climb , the fuel tanks mounted at 'the wing . ,/ tips showed themse•l ves• superior to the taJ1ks mounted inboard beneath the- wings . With the tanks carrying rio fuel', the range of the airplane with .the tip-mounted , . tanks,. was estimated to .be 5 percent greater than the range with.no tanks , while the rang~ with the inboard~ mounted tanks was about 9 percent -less than· that with no . tanks . The decreases in maximu.m speed and rate of climb were indicated to be considerably less for the tip mounted tanks than for the inboard-mounted tanks. 4. The only static lateral- stability parameter affected materially by the presence of the external stores was c ,, the effective- dihedral parameter . The effect 1 'lf of the inboard tanks on C7, was small, the effect of \;t1 the tip- mounted tanks was to increase the positive value of C7,. by an amount proportional to the lift \;t coefficient and the effect of t~1e three bombs was to decrease Ci~ by a consta.~t amount over the lift range . 21 · MR No . L6F25 ,, ~ .-_.; • • r,· • ~ 1 ·• ' ~· : ·, ~ .·, \ • I t • ,, • • · • . - .,• '" ' \ ( The large increase in c1~ at high lift coefficients caused by the· ·tip- mounted:· tanks was regarde-d as·. , . undesirable because . 0f the tendency it· gave toward oscillatory instabili ty; this tendency was aggravat·ed by the increased moments of inertia resulting from the, wei-·g ht of the . full. . tanks. . ~ • I •• 5. For, ·a full - p9wer_ wing- level' climb , a t · CL := 0_;7, the estirn.ated _:rudo.°er ·.and· ·aileron def-lections ,requirep. to trim out the a.?1:YJ?IJ!l~-t-r -:l.c moments resulting .from .the presence of a single full fuel tank mounted either inboard or at • tne.. tip -_were well within the available range of ¢l.~fl~cti-ons . j • C ;"I 6. Tl].e aer_odynam_.tc effects of the rockets were negligible . .. 7. Defl1c t ion _of _tp.e fy.se lage di_ve: prake,s caused -a nose- up change in tri~1 and a rearward_. ( staole) . shif,t of the neutral p,oint:o _T1'le a.mount .of . ~:leya;t_o:r re.quired ·. to overcom.e .. _the · change _J .µ. trim was well -:. wi_thin . th_e . • < • available r _ange of._defle~tion . It .wa~ _- ~st:i,..rnated tha·t a dive-brake deflection : of 90° would decrease the · terminal Mach numbe::r .in a vertica;L dive by ab0ut · 0 . -1 • . : ,· ~ ., . ' .. 8 . The er-~ tic al J:ia_"~h nu1nber of t:be- V".'" fron t canopy, .. ' ·-· as estimated from pressure-distri bution·: da.ta obtained -at a low Mach number, was about o.o~. greater than the . · · critical Mach number of the original canopy. The eff'ect of power on tl)e crit.ical. Mach number of : either · canopy · ·. was negligible -:·· . ' - 9. The estimated critical nach nu~1;1ber of the outside nose of tl1e jet entrance, duct· was greater· than the flight Mach number for bqth power conditions ., tested • . Pressur.~.- .. distribution tests showed sharp int~r:nal pressure pe~ks· which would lead to separation and, . consequently, a·.. decrease in p:r,e~_s'4re. -reqovery at the engirn~ . It was -, ' 22 MR No . L6F25 suggested that a smaller nose radius and a change in the internal lip shape would help to alleviate the pressure peaks. Langley Memorial Aeronautical Laboratory National Advisory Committee for Aeronautics Langley Field, Va . J.t0a~•1·,h1 U, -,~cft..J" ✓ Warren . • Tue ker '. r Aeronautical Engineer , ' :}fGvn~ uJ -f~~ Kenneth w. Goodson Aeronautical Engineer Approved: p{_~ C. fi~lJ.·._;;__:, /t;,11- H;rtl~y A. Soule,.• . Chief '. of Stal;,ili ty .Research· Divi&ion ES . : · · -~ ' ... 23 MR No. L6F25 REFERENCES 1. CHllis·, Clare'nce L.; and Andrews , .Thomas B ., J1~ •: Wind- Tunnel Tests of a 1/5-Scale Model of th~ ... ;{epublic XP- 84 Airplane (Army Project Mx - 578) . I - Longitudinal Static Stability and Controlo NACA-M~ ~~o :~;· ·L6D05 , Army · Air. r?rces ; .- 1946.. · · ·· - .. · , 2 . Gillis , Clarence L ., Pol!lamus, Edward C • .:, and Gray, Joseph L ., Jr.: Charts for Determining Jet Boundary Corrections for Complete Models in 7- by ·,.:·:.,. ,J. Q.-· Fo_ot Plos~-fl Rectangular Wind Tunnels . NACA .. ,ARR No . t5G31,' 1945 . 3 . zi'm."!le·rmah, Charles H., : An Analysis of Lateral .. Stability i n Power-Off Flight with Charts for Use -~ · .i,.. . ._- ..: in . De·-~Jgn . NACA Rep . No . 589, 1937 . . ' - j ... , ... '\. 'I . • ·, . . • :..;• • ·• 4 •. Phillips'.,· W. . H . ; _Crane , H . L . , and Hunter, P . A. : · Eff'ect of Lateral Shift of Center of Gravity on Rudder Deflection Req,uii"'ed for Trim . NACA RB No . 14106 , 1944·. . .. , , · -- -·--- · _ t 5 . Gillis.• Clarence L. , and Deftohma;nn,· Se}'--riiour .J. : ·N ind- Tum:el Tests · of a -r/5- scale Model~of the Repub lic XP-84 Airplane (Army Project vrx-578) . II - Lateral Stability and Control . .l'JACA r,:R No,. L6Dl5, Army Air Porces , 1946 . 6. Bielat, Ralph P .: A Simple Method for Estimating Ter::1inal Velocity Including Effect of Compressi bility on Drag. NACA ACR Ho . L5G31 , 1945 . 7. van K~rmful , Th.: Compressibility Effects in Aero dynamics . J our . Aero . Sci ., vol . 8, no . 9, July 1941 , pp . 337- 356 . 8. Delano, James B . , and Wright, Ray H.: I~vestigation of Drag and Pressure Distribution of Windshields at High Speeds . !HCA ARR , Jan . 1942 . '\:iR No. L6F25 TABLE I PHYSICAL CHARACTE.USTICS o:? TTIE REPUBLIC XP- 84 AIRPLANE Type ...... Jet- propelle~ fighter Wing : Area, sq ft . ~ ...... 260 Spa...ri , ft . • • • • • • • • . • .. ·• • • ·• • . • • 36 .42 Asuect ratio .. ,. • • • •• •.. • • I •'I" • . • •. • • • • • 5 . 1 Taper ratio· ...... · .; .' •• : • ·• • • . • • • • 0 . 57 Dihedral , deg • ..... ~ • • • • • • • • • • • • 5 Incidence· a·t 'statioh '27' fn.' r"roin 'center fine ". . • 0 Sweepba-ck» 25 - percent chord_ line', deg •• _ •. ••, 3 . 08 Geome"tric twis't, deg '(washout") , ; .... · _- • • • • • . 2 Mean aerodynamic chord (M . A . C. ) , f t • • • • • • 7 .39 Statio:::i. zero to 50- percent chord of M. A. C . , ft • 16 . 5 Airfoil section •• •• •. Republic R- 4 , h5-1512- . 9 Original horizontal tail : Area, sq ft •••••••• • ••••• ~ • • • 48 . 5 Sp an, ft • • • • , • • • • • • • • • • • • • • 15 • 0 Aspect ~atio • • • • • • • • • • • • • • • • • 4.6 Elevator area behind hingeline, sq ft •••••• 13 Root-mean- square chord of elevator, ft •••• 0 . 990 Airfoil section ••••••• Republic R- 4 , 40- 010 Revised horizontal tail : Area, sq ft ••• , ••••••••••••.• 57 . 1 Span, ft ••••••••••••••• • ••• 17 . 0 Aspect ratio ••••.••••••• • ••• • 5 . 07 Elevator area behind hinge line , sq ft • • • • 13 Root- mean- square chord of elevator, ft •••• 0 . 990 Airfoil section •••••••• Republic R-4, 40- 010 Vertical tail : Total area, sq ft •••••• , •••••••• 35 .80 Rudder area be~tnd hinge line, sq ft ••••• 7 . 39 Height from center line of fuselage, ft •••• 8 . 10 Root- mean- square chord of rudder, ft ••••• 1 . 21 Airfoil section ••• , •••• Republic R-4, 40- 010 High- lift device (slotted flap): Chord • • • • • • • 0 .2~_9c inboard, 0 . 266c outboard Span • • Extends from wing-fuselage juncture to o.51~ High- lift device (split flap) : Chord •••••••••••••••••••• 0 . 25c Span • • Extends frcm ·,; ing-fuselage juncture to o.51~ i.;ATIOI:AL ADVISORY COi.i:~ITT:SE FOR AE71'.0:IAUTICS MR No . L6F25 TABLE I ..-, : ' . ·.· ... PHYSICAL CHARACTERISTICS Concluded Weight and balance: ·;_:; ' ., Normal gross weight , lb ••••••••• 12., 500 ·:. V/irig: loading, ·lb/sq . f,t • • •. • • • • • • , • L~8 . 1 Normal center- of- gravi t'y ~6s i'ti'orr, ·peq:,cen,t • . M. A. C •••• • • ••• • • • • • 26 .45· ·ee.nte-r-- of.- gra vi,.ty; r:ar1:ge_ , . percent • . ."M .•A .,.c .. •• ., ~ ,, "'· • •. . . •. . •. •• ;. •,!. . NATIONAL ·AD VISORY. ' , . : , coh::>nTT:2E: ·Fem A:SRo~rAUTIC$ '} . ,• -~ . r, '•-' .. l .· .; . . ' · 1 •, ,. ···- ,.) ·- •· ,· ,· :. -~ MR . l .J. L6F2 5 FIGURE ~EG.E JDS . Figure 1. - Three-view drawin~ of-the 1/5-scale model of tte Republic XP-84 airplane (Army Project M:x:-578) with original horizontal ta~l. · Figure 2.- System of axes. Positive values of forces , moments , and angles are indlcated 9y arrows. Figure 3. - The 1/'j-scal,e model of the Republic XP-84 air plane (Army Project MX- 578) mounted ~rt tpe 300 mph 7- by 10-foot ,:;unnel. ·· · F'igure 4. ~ Flap -;,0.si ~ion for tests of 1/5-s-cale -~odel of Republ:t c XP - 8'4 airplane ( Army Project MX-578), with slotted flap deflected 30° .. Figure 5. '."' · OriginaJ and revised horizontal tails tested on the 1/5-scal -"3 r.-odel of the Republ:b XP-84 airplane (Army Project il,,c-578). . ,. · · . : Figure 6.- Inbo~~d p~ ~1i1on of fue l . tank test~d o~ the 1/5- scale model of the Republic XP -84 airplane ( Ar1cy Project MX-578) . Figure 7. - vring-tt°J p9si tion of fuel t _ank t _e sted on tre 1/5-scale .. model of· the Republic ~P-84 airplane ( Army Project :MY.-·578 ) ..• Figure 8. - Fuel tar_l:c~ mounted at the wing tips of the 1/5-scale model of .the Repubii c :XP -84 airpl~e . ( Army Project ·Mx-578). . . · · Figure 9.- Posltion::; of bombs tested on :the · l/5-scale model of t'b...e Repv.bli c . XP-84 airpian8 ( Army Pre jBct MX-5.78). Figure 10.- Detatls f rockets t0sted on tha 1/5-scale r:;odel of the Ra;:n-.blic XP-84 aj rplane · ( A;:rrry Project r'X-57~). · . Figure 11.- Fuselsge dive brakes tasted on the 1/5- sca:le model of.the Republic XP-:?iLi. airplane {Army Project MX-578). · MR No . L6F25 FIGUIB LEGENDS - Continued Fi0ure 12. - Location of pressure orifices on the 1/5- scale model of the Republic XP - 84 airplane (Army Proj e ct M:X:• 578) . {a ) Ori ginal canopy . (b) Nose . Figure 12 .- Concluded . (c ) V- frJnt canopy . Figra',9 13 .- A comparison of ordinates for the design n ci se and the a c tual n0se as ter;ted on the 1/ 5- scale model of the Republic XP - 84 airplane (Arrey Project MX- 578) . Figure J.4. - Tb8 original canopy tested on the 1/5- scale model of the Reoublic XP - 84 airplar,e (Army Project MX- 578): Figure 15 . - The V- front canogy- tested on the 1/5-scale model of the Republic XP-04 airplane (Army Projec t Tu':X-578). Figure 16.- Variation of eff2ctive thr·ust coeff:!.ci ent with lift coefficient for the republic XP - 81+ e.·" r plane (Army Project Wi.X-578 ) Idling power (80 :percent rpm) at sea level (power c ondition A) ; gross we i ght = 12 , 500 lb. Figure 17 .- Variation of inlet- velocivJ ratio wi t h lift c oeffic ient f or the Republic XP - 84 ai rr,,lane ( Arms· Project MX- 578) . Gross wei ght= 12 , 500 lb . Figure 18 .- Variation of t r im lift coefficient with angle of attack used making pr·essure - distr-ibution tests on the 1/ 5- scale model of the Republic X.P.,84 airpl ane (Army Project MX- 578) . Cruising confi 6uration. Figure 19 .- Effect of stabilizer on t r..e aerodynamic char acteristics in pitch of the 1/5- scale model of the Republi c XP - 84 e.irplane with origina l horizonta l tail. Idling power. (a ) Cruis1ng configuration. 2 MR N~. L6F25 .-. FI·1UPE LEGENDS - . conti-nu~d Figure 19. - Continued. . fb) Landing configuration (slotted r1aps 'defle~ted 30°). ~ · ·· Figure 19 •.- Cont1:nue;d. · · ' - . ( c) _L.and"ing c§)nf!guration ( slgtte.d flaps def~ecte_d .,.30°; •ailerons droop~d.. 15 ·.) . . Figure 19.- Concluded. ,.; ( d) Landing configuration { s-pli't' flaps. deflected 60°). ' - Figure 20. - Efjfect of stabilizer on the- aerodynamlc char acteristics in ?itch of the 1/5-scale model of the :· Rep·ublic XP-84 airplane with revised horizontal tail. Idling power. {a) Crui ~ing configuration...... Figure ··,20. - Concluded. ' { b) Landing ·configuration {split flaps deflected 60°). Figure 21.- Effect of elevator defiection on the~ae~o dynamic characteristics in pitch of' the i/5-scale model of the Renublic XP-84 airolane with revised hori~ zontal tail. Idling power; it = , 0°. . . (a) Cruising configuration •. Figure 21.- Concluded. :•'.. {b) Landing configuration {split fla~s deflected 60°) . .' • I Figure 22.- StlcI{-flxed neutral 9oints of the_· .. . Republic XP-84 airolane wi·th original hori zontaF' tail., as d 2 terminad from tests of bte 1/5-.s c.ale model. Idling 9ower, landing conf-iguratimi. , . .,,. .,. '\. 3 \ I . MR No. L6F25 FIGVRE LEGF!ms - Coritinue4· Figure 23. - Effect 8 f revised hori. zontal _taJl on the ·. sttck-fi?(~d neutral -po:Lnts.. _of tte Republi"c XP-84 air'J_la.ne, as determ+ned from tests, of the 1/5-scale model". ·"Idling_ ;iowe~~ · · . , ' \ ~ . •· Ftgure 24.- Effect of external fuel t -anks qlnd bombs on · t11.e : aefop.ynarnic charaotertstic~ in pitch of the 1/5-s'caie mo • • • C • .... -, .. with original h'ori z6i1t-al . .ta.1_1. Power off, · cruising :: .. ' · configurations. ••• ~. ' • • '•I ( a) Tanks off; bomb~. off~ Figure 24.- continried. (b) Right .tank in inboard posi t ,ion; left tank cff'; bombs off. Fibure 24.- Continued. i ,... ~ ' ' 't~ •.• ( c) Both ·tanks i:n- _inboard posi ti.on; bombs off. .. ' . ' . ,..,. ·1·· .. ·Figu!e 24 . .:. C·on.tinue d~ (d} Rig:r....:t tan}'~ ln· tip: position; left tank off; bombs off.. . , ., .. ·· ·· · Figure' 24~- ·continued. . .· ,· : ~ . ; ... . (e) Both tanks in tip p 6~ition; bombs off. _: :' ·. ,·· . ' • I ~ • . . ~ . , . ( f) Both tanks i'i:n .' t"j,..p _position; l e ft inboard 1' • _# • ! '.' bomb on, •.tip bomb_s off. •.• r .- • •· .• '"! ;. , ,figu.re: 2L~. - .conctuii~d.-... ,. :_ • • I - ·•• , {g )° 'Tanks . off; - le.ft .inboa~d bomb on, tip bombs on. .., · -. · :: F'igllre 25.- Effect of extamal fuel tanks and bombs on t~e stick-fixed neutr al ? Dints of the Republlc XP-84 airplane, as determined f rom tests of the 1/5- scale model. Power off; cruising configuration. 4 MR No. L6F25 FIGURE LEGENDS - Continued Figure 26.- Effe~t of external fuel tanks and bombs on the lateral-stability derivatives at small -angles of yaw of the 1/5-scale model of the Republic XP-84 airplane. Power off; cruising configuration; it= oo. •· (a) Inboard tanks. Figure 26. - Continued.• . l . • I . . (b} Tip tanks • Figure 2t;°.- Concluq~d.· · (d) Tanks and bombs. Figure 27 o- Effect of carryL1 g fuel in the wing tip tanks on the dynamic lateral-stability boundaries of the XP-84 airplane. Cruising configuration. , . · •. . Figure 28.- Effect ·ot-· inboard fuel tanks· on · the aerodynamic characterj~tics in yaw of the 1/5-scale model of the Republic XP-84 airpl&ne~ Power off; cruising con figure.tion; .:1-t :;: _o 0 • (a) a. = 0.1°. Figure 28.- Continued. (a) Concluded. Fig we 28.- Continued~ ·. ,. . -: ' (b) a = ,8. 7°. :. Figure .28. - -concluded. (b) Concluded. ·Figure 29. - Effect of ti 1;,-mounted fuel tanks on the aerodynamic-characteristics in vaw of the 1/5-scale model of the Republic XP-3h airplane. Power off; 0 ·cruisi~- configurat~on; it= o • (.a) -a = ·0.1° 5 MR No • L6F2 5 FIGURE LEGENDS • c ·ontinued ,- . Figure 29.- Continued. 'I.'• j ·: . , -(a) Concluded .. - ..,. . ~ . . ., . Figure· 29 •.:.. : CcintJnued~ • • 'l> - Figure 29,- Concluded. ( b) Cone luded. · •·· I • • ,.. ·1 .,,._ ~• 1 Figure 30.- Effect of fuel tanks and b'orr.bs 'on .the aero dynarrdc characteristics in yaw of tµe. 1/5-scale model of the Repub2.ic XP - 84. ai rplan~~ Power off;_ cruising configuration; ·1t = o0 • .-. · ·, ... • ~ ~ . ', : • • • 1 _: r. '10 . ,. .'. ·: .. ,~ ·.. ( ·a ) -a. :-- v.. , .. ·,:_, · ... ' Figure 30 ~ -- : Coi\tinued. · · •·.. .:.- . (-a)· .- Cone J.uded. • • •• :.. .. ~. "' _1, I ~- ' t . . ) (b) a = 8 7° ·· ,· ,- ·- r, \ • ". 1 ..., - Figure 30 .- Concluded. I • •. : •' _ ..,. . :: (b) ConcludeQ..• - .. " , . . . ' Figure 31. - Effect of stabilizer on the ae'rodynamic characteristics in pitch of the 1/5- scal~~model of the Republic XP - 84 airplane wfth, revi·sea·· nori zontal t&.il. Idling power ; cruising configurati.on .. -.T'!,vo ,. • rockets beneath fuselage. •· Figure 32. - Effect of roe kets on. t,he 'a:e·rody'nami c ch13-r.a9-:- " · · teristics in pitch of the 1/5... sca.le mpdel · of 1 the _. ·· .: - .- Republic XP - 84 ai rplan:e with :revis~4 )Jori zo·ntaI _t _e,11.· · 0 Idling power; · cr~sing conf.igu:ratto_n;; ·1t.. = ·. o ·• · .. · . . • .., • • ,. l •' • • • Figure 33.- Eff·e·c·t 'of rockets on>1;;h~ .s.tick:...fixed neutral points of the Republic XP - 84· airp lane with revised horizontal tai 1 , as determined fro.m · t'iists of the 1/5-scale model . Idling QO\"er; 'cr~ising configuration. 6 MR ;No, L6F25 , . FIGURE IEGENDS - G-ont-inued F:i.gure 34,- Effect of fusel~ge dtve~brake deflection on the aerodynamic characteristics in. P.i tell_ of the 1/5-scale model of the Re9ublic· XP-84 ·airplane with original horizontal· tai.J_. : Idling: 1fower, cruising confi.g'U!at:i.on • . (a) Dive brake,s retracted •. 34.·__ · ' Figure Cont i.nU(sd.' : - ' -; ·. (b) Dive brakes deflected 60 0 • ' ., Figure 31+.- Concluded. , (c) Di v e- brakes deflected 90°. Figure 35.- Effect of fuselage dive brak~s on the esti ~~ted1 term~nal Mach numbers .of the Republic XP-84 airp.lane in ;vertical dives. EstimatErs based on wing - cri-tical Mach _p.urnber of o·. 755 . Gross weight = 13 , 3 24 1 b; . _ . . , . . Figure 36:- Pre,s_sur~ di'stri butfon o·ver ·th~ top of the f;uselage of the 1/5-·scale rp.odel of the· Republic XP-84 airplane . with the· original canopy. : . . : .... ~· ' ., " . (a) Power condition A (idling power (80 per cent rpm) at sea level; a 9proximately full power (100 percent rpm) at 30,000 feet). Figure 36.- Concluded. (b) Power condition B (full power (100 o er cent rpm) at sea level). Figure 37.- Pressure distribution over the top of the V-front canopy tested on the 1/5-scale model of the Republic XP-84 airplane. (a) Power condition A (idling power (80 per cent rpm) at sea level; approxirrately full power (100 percent rpm) at 30,000 feet). 7 Tu'R N~. L6F2 5 FIGURE LEGElU)S - Concluded Pigu_re ?.7 .-. ?oi;iclud.ed • ··.·: .(b) Powar condition B _(fuJ.:1. power ,(.100 pe± - ceri't _. rpm)' ~9:t : s.ea level.))...... . ~ . ... . Figure 38 .- Pressure distribution over .the ·. nos-e of -t11e -· entrance duet of the 1/5-scale model of ' the Republic XP-84 ai rpTane . · . : . , \ (a) Power condition A ( idling pow el! ( ~O __ per- . cent rpm) at s~a :Level; a?proxirr:e.te ly full power (100 percent ·rpm) at -30~000 .feet) . _.: Figure 38.- Concluded ...... -....-. (b) Power condition B (full . power {~~O per- 9~pt rpm) at sea level) . Figur~:jsr-. ·c~i·tical -Mach ·numbers - of · two .,canopi.e's f'.or ' ·the Republi.c XP-84 airplane, .as es.tin1ate·d , froin .. . ·. presrnire- di stri'b-ution -test.s oJ, the, +/5~3=.ca,le •, \ model. Power conditions A and B...... F~EV.I~~ -- 40.~ -·- ..'' c'ri.ti-c al . Mach m.imbe'·r ·s- O'f_ t.hi?, , outs iq._e -of the · upper nose of · the ·· entranc·e duct. .. of ~· the, Republic . ; XP-84 airplane, as es-tima ted, .from p ress,u:Pe,- di st:ri bution te~_t.s . of 1 . ~ : .:. ' ' ; - .; : . :.. . J • 4 ' • 11 ' • ••• - I ..·.. . . ' : ' ~ f ._• ·. 8 \' ••• • •• • • • • • • •• • ••• • • •• • • • • • • • •••• • •• • ••••• • •• • •••• 3S.86J - -~ -. I l. Sym t - i 42. 000 All d1mens10ns ,n inc hes -- ,7. 309 ___ _ -----3S .6IO --- - 39 .800 , _EJJ.§_r.J NATIONAL ADVISOAY COMMITTEEf'OQ AERONAUTICS 1 . Figure 1. - Three- view dra wing of the ---scale model of the Republic XP-84 5 airplane (Army Pr oject MX-5781 with original horizontal tail . • •••• • • • •• • MR No. L6F25 • •••• • • •••• • y ••• • • •• ••• • •••• • •• ••• • • ••••••• • X Relative wind M X Relative wind NATIONAL ADVISORY COMMITTEE FOR .4ERONAUTICS z Figure 2.- System of axes. Positive values of forces, moments a.~d angles are indics.ted b~r arro.. s . ••• ••• • ••• • • ••• • •••• • • •• • • • • • • • •••• • •• • ••••• • •• • • ••• -- - ~ '"' NACA LMA..L 45134 I 1 •0 Figure 3.- The -scale model of the Republic XP-84 airplane (Army Project MX-578 )! 5 l mounted in the 300 mph 7- by 10-foot tunnel. l&tlel&L Ufleeat eenltta NI &IMl&fflle ...... , •--l&L &IUl&fflC&L S.UOl&ftll • lo&HLII rta.a, fl, ., .... • ••• • .:..... -~ r--o.oo5c I --o.025c NATIONALADVISORY 3: ::0 COMMITTEEFOi AERONAUTICS z: .0 Figure 4.- Flap ,eoaiticm tor teats ot 1/5-scale model ot Republic XP-84300. airplane (Army Pro3ect IIX-578) w1 th slotted tlap deflected ••• • • • ••• • MR No. L6F25 • •••• • ••••• • • A11 dimensions ,n inches •• • • • ••• • • S M •••• • • •••• • • • ••••••• • 0 r------~- - Elevator Hinge Line(707. Chord) 1 I t4------t6 ------~ ~ ------18 Original tal I Area ~dded to original to.ii - Eleva. tor Hinge Line {70 "Z Chord) ~ 3.4 ->--C'------16 - ~ ------2 0.4------_____.i NATIONAL ADVISORY Revised a1 I t COMMITTEE FOi AERONAUTICS Figure 5.- Original and revised horizontal tails tested on the 1/5- scale model or the Republic XP-84 airplane (Army Project IIX-578). ••• • •• • •• • • .•• • • • • • ••• • • • • • • •• • •••• • •• • ••••• • ••• .• .. • t------4------25.30----- "Fvs. Rr:F. Plane 2.2.0 Ji Ref. L 'rl + 5° ------=--=---Front View Fus. Vert/cal /JI/ dimen.sic,n5 in Inches. A -006 J/ Rel.Linc Tt.15. 'Ke! Plane 7a-ti ,mx. d1a. 5.6 1.145 L~ngth 29.Go Sec. A-A /.0/4 Tcm/<.no.5e ----+---3.8// tan'!..!./4:_,i~--k--- 3: NATIONAL ADVISORY :::0 ~-----/53/ ------~ COMMITTEEFOIi AERONAUTICS z .0 Figure 6.- Inboard position o! tuel tank tested on the l/5-scale model of the Republic XP-84 airplane (Army Project MX-578). ••• • ••••• MR No. L6F25 .•••• . . • •••• • • •• • • •• ••• • •••• • Sec. A-A •••• • • .fl • ••••••• • 45.02 to f'u~ . t ------1 All d1mcns1on.:-, m mches. Tank mat. dl(f. / s.6 \ A 29.,o A \ '----+--- _ 0g Ref. Lme (.50% chor=-d_;,_,rx:.--=-) ___ -+ --4------+-- \ I I I / / l'lolc: In side view., tan!< t_ 1s .z.0° nose down with respect to f'u.se/<19e r/. NATIOtfAI. ADVoSOQY ITTUfOl~ICS Figure 7.- ing-tip position or tuel tank tested on the 1/5-acale lllOdel or the Republic XP-84 airplane (Army Project IIX-578). • •• •• • • • ••• ••• • •• • • • .•. • • • • • • • • • • • •••• •• • ••••• • •• • .. 1 Figure 8.- Fuel tanks mounted at the wing tips of the ---scale model o f t he z: 5 0 Republic XP-84 airplane (Army Project MX-578) . • ,,ro1,L ADVIIORT COMMITTIIFOR AIROIAUTICI LAIOLIT MIMOllAL AllOIAUTIGAL LAIOl.t.TOl1 • LAIOLIT Fll~D, YA • •• • •• • • •• ••• ••. •.. • .. ...• .• . .:.• ·•.. ·• .: ..• ·• .. · • ..•••· t Sym -- 0 Front view, showif'/9 spcmwise. loc&t+-ions of bombs. Hofe pos/f11ms of fms, 7.a3 -I 8 ·93 -t, Plcm re-f. line C:KJc) 2.ao/4-!J-'Plan ref. line (.50c) .02~ mm1m11mc/9V"(.lnce Pt?ra.lkl to fuse/age ref line z 0 Inb1X1rd bomb /occd/on Tip hom/J location Figure 9.- Positions of bombs tested on the l/5-scale model or NATIONAL ADVISORY the Republic XP-84 airplane (Army Project MX- 578). COMMITTEEFOi AERONAUTICS -... .• •- ··• ••••••• • MR No. L6F25 ••••• • • •••• • ••• • • •• ••• •••• • • •• • •• • • ••••••• • ------=sr~mmET•~•1 FUSf'1.A_G_J!___ _ N C'\J A All dimer,s°,Qns !fl inc/Jes, k 1.76 .. 35.3 to nose .....----5.1 r=uselage contour J __ _ 1.6 14---=------13.8 ------..l Section A-A NATIONAL ADVISORY COMMITTEE FOi AERONAUTICS Figure 10,- Details 0£ rockets tested on the 1/5-scale model of the Republic XP-84 airplane (Army Project ' •-578). ------==:::~~:::::::::::::::::::::::;::::::::::::::::::===:::::_-===::=::==------• •• •• •• ••• • •• •.. • • • • ~• •• .• • • •. .• • • • • •••• • •• • ••••• • •• • ••••••• • A .:5tDE VtE.•W JPACE.5 FILLED Fo1c. ONE T ESr A----J S£CTION A-A NATIONAL ADVISORY ALL DIM£N5l0N5 IN /NCffl:.S. COMMITTEEFOi AERONAUTICS Figure 11.- Fuselage dive brakes tested on the 1/5-scale model of the Republic XP-84 airplane (Army Project MX-578). z 0 NAllUNAL ADVISORY COMMITTEEFOR AERONAUTICS • •••• • • • ••• • ••••••• • MR No. L6F25 .••••. . • •••• • ------·-- - - 40."IO'------••• • • • • ••• • •••• • •••• • • • ••••••• • { Fuse/aqe (a) Original. canopy. All dimensions in inches I <...... _4-. _ ....L. _ _ ...__ NATIONAL ADVISORY COMMITTE1 FOi AEIOIWITICS (b) lose. 1'4ure 12.- Location or pr~sure or1!1cea on the 1/5-scale aodel or the Republic XP-84 airplane (Arlll.Y Project KX-578). ••• •. .• ••. • • ••••••• • .•••• . . • •••• • • •• • • •• •• • -C, ._ . ..., . MR No. L6F25 :, .... ~3.27 ----- ,f().27 ------37.27 ------34.27------3/.27 ------29.77 ------27.35 _ .., -- 25.95------23.95 ------22~5 ---2/.95 ------2/.,fS - ----20.95 ----/8.95 17.95 /6.95--..i /6./§ NATIONAL ADVISORY COMMITTEE FOIi AfROIIAUTICS All dimensiofls in inches (c) V-rront canopy. Figure 12.- Concluded. ••••• • • • •• • • MR No. L6F25 ••••••• • .•••• . . • •••• • ••• Desicm Nose Actual Nose • • ••• • • X X,,o ¼.o Yi..(. Yuo Yu-l • •••• • Yui YLo ¥Li • •••• • 0 2.200 2.200 2.200 2.200 2.20 2.20 2.20 2.20 ••••••• .40 - I .9tfJ - 2.020 2.57 /.95 2.56 2.00 • • .80 2.714 l.945 2-714- 2.045 2-7+ J.93 2.72 2.02 /.40 2.91 I /.900 2.9/1 2-/00 2.95 - 2.93 - 2.40 IJ.173 - 3./13 - 3.22 ,- 3./8 - A.Jot.e: 01/l'ermce m ordmt7ks too S /Tlt1II lo Ix slmm qccuratelj 111 sl:elch ochw'. .20 R. I I I I I ~✓ Ducf rseparowr - ,------+------1-~- l I All dlmtn.5/Pn'J 1n inches I .20 R. NATIONAL ADVISORY COMMITTEE FOi AERONAUTICS /.40 Figure 13.- A comparison of ordinates for the design nose am the actual nose as tested on the 1/5-scal.e model of the Republic XP-84 airplane (Army Project IU-578). ••••• ••••• • • ••••••• • MR No. L6F25 •••• • • ..... 0 I 2 3 4 5 6 ••• • • INCHES •• •• • •••• • • •••• • • • ••••••• • .irron1, view. Three-quarters view. Side view. 1 Figure 14.- The original canopy tested on the --scale 5 model of the Republic XP-84 airplane (Army Project MX- 57,9) llflOl&L &DYIIO&T co•• rffl• roa a1101aotr.1 CONrIDIITIAL UIOUT ·••oaraL &IIOl&OTICAL UIOliTOll - LaJ•L• T FIZLD, ,,. •••• • • •••• • • • : ...... • • MR No. L6F25 •••• • • • •••• 0 I 2 3 4 5 6 ••• • • INCHES •• ••• •••• • • •• • •• • • ••••••• • Front. Ylew. Three-quarters view. Side view. 1 Figure 15.- The V-front canopy tested on the --scale 5 model of the Republic XP-84 airplane (Army Proj e c t W4TIOl4L lffJWO&T -1- N& .....,n,c, MX-578). CONFIDENTIAL UIIIJ.n WIIIOUiL UllOUftlCiL LUO&lH&T • LlHLIT PIILI, U, , ., ...... •• \ • \ •• .•. .: • C • • ,. ,·~1 •• • ••• • • r ..' •••• • •• • ••••• • •• ' •••' •• z 0 Figure 16.- Variation of effective thrust coefficient With lift coefficient for the Republic XP-84 airplane (Army Project MX-578) Idling power (80 percent rpm) at sea level (power condition A); gross weight = 12,500 lb. • •• ...... , 4-• ..1.. ... •• • • ~ • •• • • • • ••• • • • • • • • • • • ••• •• • • •••• • •• • •• •• • z 0 Figure 17.- Variation or inlet-velocity ratio with lift coettic18lt tor the Republic XP-84 airplane (Army Project MX-578). Gross weight= 12 1 500 lb. •••• • • • • • •• • ·•1w•• •.1U• :, ~ ... •e: • .. •••• " ••• • • •• ••• • •••• • MR No . L6F25 • •••• • • ••••••• • - ....-I 1-,:. L-:.~ - - - ~ :w . ±: - T ~ 'i. . - -·- - ,. ~- . - - . l ~ !.: ~ • ·.i. i:I -+ J [ - ~ " , ~ . NATIONAL ADVISORY - · i::- COMMITTEE FOi AERONAUTICS t I . ..,. r:-t .... l:t '--' ~~ -~ :i:a:i:.ci:=:i ~--~n:m l:+}.!t:' - ., Ii Figure 18.- Variation of trim lift coefficient with angle of attack used making pressure-distribution tests on the 1/5- scale model of the Republic XP- 84 airplane (Army Project YX- 578) . Cruising configuration. r- • ..... • • • •• • • • ••••••• • .. ... MR No . L6F25 ••• • • •• •• • •••• • • •• • ••. . • ••••••• • (a) Cruising configuration. figure 19,- Effect of stabilizer on the aerodynamic characteristics in pitch of the 1/5-scale model or the Republic XP-84 airplane with original horizontal tail. Id.ling power. • ••••• • • •• • • • •••••••• • • •••• • MR No. L6F25 • •••• • •• • • • • •• •• • • ••• • • •• ••• • • ••••••• • (b) Landing configuration (slotted flaps deflected 30°) . Fi gure 19. - Continued. • ••••• • • •• • • • MR No. L6F25 ••••••• • ••••• • t -~ • • • t, r '! I "'-.:~ I •••• ~ ••• I· ., .f I f :, • • ••• T t • "' i.. . • • ~ 'l'I,.;;, -~ ••• ,_, -:, , ~ I; ,, • • • t.b ..__,,. ' + r '' L • • • .:J....__., . ,L ,., ••• -/, {:) "· ' J.. l:J ...,.. ~ ,, I .. ,· -lllfM + I··• ' f _ , I -~ 7 'L ;, 1i ~ ,1 , .... -.. :I' j ' fl'i_. ,io +: ,[l: . J; l . _t 1 u ~ • f ,.., ~ ., ,,t T .j;. t;;•· r t, j j ,l ,1 it!' ' :: I' ~ If. i: ct If · Jf t ~ •! ' ff lb', ;pc ~ 1 EfF, I I l 'k 1 • k'~ tj "i 1 ll J ~f, 't 'i ' "' fl lk ,f ,,. fJi fp ,1 r+ 1 't; •!:, .. ( j ( t ~ f - :· 'ti ti '.l ~ + " i f'· ..' ... ' a' •I ' ti~ : · 1 " ...... ' ~ ... •f' ·' C: j !,_, 't J > ' ~ ,~ ~ > ·'• t l .. .,I ' 1... Im ' -~ (] ,-- 'j [ti t- t I ' .. ~ µ.t t'..J l ~ . ·.. j \ • I JR ' l..\c ! IT I ·c- \ ... f .. p-1 ,, ~ .flt, i t j ,, tE ;{' l ,l:t ~ ,.f' j tt ;: m; liJ ,: .t- ~ VJ •I f ~ ''it ' j:i •; I. I 1, Jj . ,t,· +# 1, I> '>- [1 I ... 1' C fl ~ ' It i•f J'i :J ~ h le " c'• .. ~ .:, ! h ,, i'f t\. I 'i t· b II 7 F ·- l'i- • 'i' 1 ' 'I 11- l'i-. ~f I •f'.~ Ii •I' I {(lj !I ,t., ~· I ::- '- ·~ . t I• .. r ~ t'' II ' ...'" ' ~ ;< l~Q Vf i "1lfl / ' • i ;i ' ' . '/ ~ I ;::~ i'ilii 1:t l NATIONA.L ADVISORY .,, tl ' r 1-.:i ' ' COHMITTU FOi AEIIOIIAUTICS I :r. ,'l ~'!! 'l ,.3 '~ - "07 ~- 4, - I ( ·() • 1. J) IQ l ~ ? ) - - ...... , j f t, j jl 'r / ,o ;, ~"" ffti ·, r' t r '" - I n'", C - - ~ ' I - (c) Landing configuration (slotted flaps deflected 30°; ailerons drooped 15°). Figure 19,- Continued. -..6 C -•• .. • ••••••• • • •••• • MR No. L6F25 • •!•· • •• • r • • • I • •• ii ' ; I .. ' 1rl.r. .,.\ l • • r re.; ir, ~ .,. ~ I> . :: . ti ".'; ' a l i;: ••• "' 1, . '+ ' I• ,, ~ 1J ·~ ,,,,: t' k ,I ,!_• ~ ., • • • ~- 1 i ~ ~ ,+ r- :I '} • • • ' l:J~ : ••• ,.. . /1 r-,, t\. ~ Lr ... r j a .. I ;, • ' ' ~ ~ - ~= I "" "-1 :J ' ::!' ~ •••••• ~ ,t>,,. 1. • • .± f, t ,.. ~ ·' I T U". J . lT ,., -ITT' l I •f-,1;, ...... ts. ;: !.r ,f•• ~ I '-' 7 Tl ' ._ :,- f..• .1,, lul If I• :t + n .. : ..; ' -. ~ Ft, I I, ... ~ 'll, ~ .~ ;;,i~. ) ~ +j : ~ ;r t i ·- ," ~- ·' ,j t £ 11 l} ~ ' ,,, ~ :, ~ \j E 1 'ti _, IJ rt N it," lfn ;n ,..... ~ .. f, ~ ~ If I f li.1 .4 " ., ' t, I . ,.,. ~ It l, tr r It • ~ "· ~ j ... •: I I +l l ~ t. Ii Ki : j - " '- I • < ...... ~ ·,; I • <. : I i ~~ ~ .. rj I ~ CT .-. t I 1 ' 1 " ...... ' if i' I C 1. I.!) -j ] ~ 1 II• le, I f IE +..; ~ t'l= :, ,If'' .~.. l"t":: . V ·'t ~ .,. l i ll ; •• I'. -~t 1-.' c"'· ,: t ,! ~"!! ' I t.r J; .,l I>' • , - ~- ·,.. ~ ; dr + t ~ I iJ 'lJ : ' I ,- jl ' 1 ' I• t " ' ,,, ,p- t I I> ·,1· r .. Ir ., • 1 r 1, :,, ,, h.., ] c.. ' I, I I-' ~ .;;. ~ I .1 ' CJ ..... t· ~ l I•• - • .. ' ~I, J •i,.' 'J ' ~. J . I I l )r ,,r t', l 'C .! I It ,. f:f l ~ L. "~ ' i ., ' I· i I ., ,t I .. ' . I T ,, {,J ._ , ,.[ ~,, ;t... 't! •I pt "' t h ,.[ 1fn:' ,f,, l ,r.. Ill c+J.' 't ,' • .._v. ~ I ·~ le ' lt' " I• 1:.1 ' L r. 1, ,. 1: + l. '1, + l • L Iii •.• " 11 ' ~ NATIONAL ADVISORY ·~,,. 1 r1I! COf!MITTCl FOi AOOIIMITICS [j i;;: •1 ,.. , ~ 1:. 1 111! V ,, 1 .~ l :t I-' , Jl •• 'd! T f I ~ r -- 'i _.;.." ;.,- ~ + t s;: \ i I.Ji ' i! ' e -..: T• +I • tf j tr .J • l f, - ... ' • ' r I LI I 1,. - i-1 ~ ,l l? r' l 'f, ,. I I - - ~ ' I l ,.,,,_ ' ,. ;nL. I ' l if ("/ oO ' ,:' ll" ;. · f.:_ .. [ I (d) Landin configur tion (split flaps deflected 60°). Figure 19.- Concluded. I • • MR No. L6F25 • • ••• -• I I I :a •••-· I I " j - I • ••• I • • I , I I I .._,_ - l l ,_ ••• -- '-- l e • • • -, ~ ,,, :o:;; I , 1 • • • It: i I \. ••• ., J -;; ,. ci ., C - ~ .n ' ' >---cl ~ - ·~~ • •1 1 _.; q ,: •••••• fH- • _\! I":"\ '""--... !t X, V'I I ,_ • • r-,,. ~ t°' 1 , ' I<; : +[ ,;; H i' 1~ i :i t . ' r~ f-') ' ' ff ' I T ..... ¥", ... . !t L i - g t , t. d ~ I> ~ "1 I j if,, \; ..... ~ .,_ I ,-1, l i e- <: ' d .,- -.....: ~ ' I, •Ji... ''ll Ir Ir :i,;J. ~ ,i._ l.J' --, a-- l""'I ' ' " f:• :>,,~ ~ 11 It i l;J-.. I> , 1\.:.1 .., ~ ' : )/ ... µ..._ t::-,r, .I 1 1~ ~ ' I "11'.._ I, ' J N l..._ lc l It . 1, I,;. "- h \ ~ ti . I,:) ,-. : tl '1:1... Ii I • . . " ;; ',, ,t : fi.i LI' 5 ' ~ ·- " 1, 1 - ~ , J. I '"5; , -, - ,t ~ ~ ·~; ..:..~ .. ~ .I' -~ rn ' , ,I. . "L r• : l- •:t- ' . ~ h ;f I j '-.I L1. Ir ' 't ' t' r.t, :,, --~ ~....; ., i' " ' j -~ " " " 11::: :t 1 + l i t I ~ JI Ir _q ,r • ;I.. ll: t, Ir t ' It I, b·,i l:" t!lf 1,- •l.,t. ' 't:!' : 1,.' :, t ,t: ' It Ir .. IF It.- • !, , 1,c± It• ~. l.i I 7ih •·.' -,, It 1 1, : : lc I, It l•r I , ir:tt !If; I T ' h :1 ~ - '" ' -~ .,.. ~"j > t, H- .i:: l ,1 : 13''- ' ... ~ 'i:.· -t• i ' ~~ . -• .... J!I 't , /f; .'f, I r IT -;:, ., ,__ ,,,..,..' (IV '• ~- "- ~ I I . ;;: ,_1-. ti; L.- - t u' I' ,- - V ' I ~ ,i - 1' , tH- ' I I~ I i T ' ~ !1 ,: -~ ,... , 1, l ' · ' ~ ! e: •If •t i ,1--., l 111 ' . 1,, 1~ i 111 11· aD .,. l: I ,rr:: r j ' ~ .... £1 .tu 1, ,. ]\ . ' J fc-7 ""( C XA "' ' J\.. ,. I r :, ' .... - 11'1 -~- ~ ' -,c,=-{ 11 'I i ' ~ I' --;; -~ ,, .,,.. 1, - t ~ l £ I .:... ;rt ,t Ir , I, ,r - ., "·· ,r. C f ::-/ ! ,~ It l " :, "Is< ' ~ 1. :1 ~ ' - I.)" ... le fl Ir l.!l 1.. , " , -St-. . Ir 1, 1-..i - 11 I -t, ~ - L-L- ,.... I . ' ... '. I) .. 71? ~ J ff ,..,. ·.:,ft= rr 'A. 'r,t J " ,. I r i i ,,_ ,. + ~ . l, T (a) Cruising configuration. NATIOMAI. ADVISORY CIINNITTU FOi - .WTICS. Figure 20.- £!'feet of stabilizer on the aerodynamic characteristics 1n pitch of the 1/5-scale model of the Republic XP-84 airplane with revised horizontal tail. Idling power. • •••• • • •••• • MR No. L6F25 • •••• • • • ••• •••• C -, . l -,, •· . • hii ~l 1 j:: •••• • l h l :'.• ~ ,. C: i:'t • t _, -!=!'-' ,rt I'" 1~ :! -, ~ '+; ~ i c l:f -"; • --,c • • •• • ~ j 1:! • • • i ' I .-i: l' ..' ·.ft :., FY ' T "- f+ • •• l_:,i :'l.• I ~- l -~l! ;; ~ • • :? il t• ~ •'ri ' . "I' ,1 Li ~· J J, g_; ::J:f ]f . , ,1 .V' ••• r i - i,: ~ ;. '.J: 1, l ';, - - =- • • • f-t, t.. -" ... - ...... - • • • ".+ " I"-:' I f ,.. ,£1: ".If: +l :fi: {F t {lJ: lli [ ~ ,_. '1 j g,· -:,: t ', /1 t f" -:-.... H'll it", i ~--1 ,Jr '.! ;1: ~-.,... m :n :, ,.,c.~ .. {;; Ir ·~ V -c, '<- f: t, 'l; r-, I;- ~ I •:- -,;1: ~ ;t P,: rtt~ ~ ~ -l' ,ft:_ _yi '· 2t. ~ :1:l ,, l i ' t ·- ( " V -M ,j- cit' j L' a fr ;,j i $ 1, 1:J ;;:-- il'- ~ -. f ' t 4- ·-' -,- J. if 1 FTT:, J ''" n ; \.. i,j,' ...,,_,. ~ 'r ~- 1£r < '· p ,1_ ! I ,'tt ~ I :j: ' :: - •"F, , ,ti,, I - I l,j: :c ...... ,;__ ,;fl f •L- .t IL r i . F 1!: ' r: ~ u .. ~ l tf lli: r t,<, Jr, . :.. ~ ·1 ., ,:-;- -- ,!, E g; ,.~ f it!.: t, ~~ [i:1- itt f;j; ilf rt "(: 'j "t, - It r ~·, !, :c J p ~F $ 1 st t t I d -~ • " -~ ~ fl 0 !,, 'tit ,; Ii' •!1:i: fill ~ ~ ~t- 1!-11 ~ '" -· , 1, • t(_ t';.' ,11± f •'j:;l ,-i:E :,L, i f:+ :, I~ " i f.i Ii " *~ E 1 iF :u JI tl " 'T ~ :E •'. !f: rr, ':i - if ' r,l t;- j if:: -f!i:' ~~ I~;; if;-J; ,l;J I~ ff~--~ !ri t •Fe, ~ :,, • 'a i, :;r I [g- 'l df j": '• !~· 1.1, IQ. -~ 1 '.I •'h ,, I~ -'J- 4-::" ';j: I ., - " .•. - ~ :r .. ~ it' ' 'i .rt:! '. lr.•, I:: •at: "'il 1'' [I' I> '4 •!~ . •: ~ I I ' ' ·:!: 't 1' H,- j _lJ _ fl-. :i'-i F i I & <.: l ~- lr-1 - ".l :t ,-.... f I. k- ,. 1 }, F . ,.., .... "f I ' ,r } ,~ ff I l,ftl .'.l ti, I ,,,: (j -:-CL .+ TT ,, . I • t ~ 11 Ir- !t \. lfil. 1,~ fj; LL' , m,. r' "' '- ~ ,,f flfi; : il', ~ ~ ' J IJ l• ,.j -~ j~ ·~ 't iF j l' I :t' -" t _'f , t, + rt, t 'l; rl -~ [j: f i a, ~ P~ : '. , 7 u- f t!i: .... Ile ., 'lr, ~., t +J h m•ltti I A I i:f; l'itl -flt il F!', : r ~ A f. ~ If, L " ' " u '4-j [_l; ~ : I I 1 ,_ IP 1 'l• ,1 I, 'I- -~ -~ 1 ft Ti ,! ~ t "'E '"l.l ,tl' 1'111 .:.a,- ,_- 1_'ih i + ,, ~ p If ""tl j I { I._ f -,, ~ rt:"_ '""" - f ·Ji! -1 , ; ~,. i I ~- µ > ! -,. i+ t l ~ ,, ft ~ f :: I"'~ ' L :; 1 ) I •j j !_ t ' ½ ..;;:; }1 ·- .!J r• C ' ' f +r '; ,i_" 't •' ! ~ I ;v :, "; ii ~ j - ·, B i i f'• s ,_ j , . '1 -~ ,l• l I l r/- T ~ C t j t-' l' I> lj.:i,. JJ d ' - 'ti ' [£ &~ ':t· ~ p I' I ~ l ~ pl I . . I ,r• • tii r.· ~ r+t ~. t• 't ,. " ,: ,,._ ' ,,_._ I[_ I 1 ~ ' ::;_._ r t f'i- # ~ ,.... '!' I ~ :!fi: _ '.; -- J U' t;, ' l E :fg ti ; _f•' .:! -i '! [f: I 11 r'' . j ' - ' C L I .~ a' ,,.. ,, j -~ "-' ,, c ...., ' t ; ' : ll1 Ji '11 ti ·~ !· ~ 1' I p I '1 J c• ,_ ><- t ,I ) •,,k J t. ~- '. - · '1 ,, ; I 1- I I I ~ . 11 r-~ _,,, l f ah t L.+ ,ii ' 0 I I h J~L!J, " 1 ,I _,,, -:.u I-~: if 14' 11- ;,r t: I <- I 'ti ., _b It ,_ 'I ,~ ., '< ' r,l j ,, 1 ;:; 18 I ~ .. , ... •' • I '·• :t 1lr 'L ,11" It •rf b'l! it r. lfffi .i; < '[}, ~ii".: cl'..,J .'.£: - -- ~ , :11_ ·- !::: j NATIONAL ADVISORY - It I c::, ::: c ;; (b) Landing configuration (split flaps deflected 60°). Figure ~. - Concluded. , ...... - .• •.. .. • -• • • • • .-·· - MR No. L6F25 -••• • . • • .• • •-· ••• • -•.. • • • ••• • ,..... - .• (a) Cruising configuration. Figure 21.- Effect of elevator deflection on the aerodynllllic characteristics in pitch of the 1/5-scale model of the Re public XP-84 airplane with r evised horizontal tall. Idling po11er; it. oo. • • •·- • .• .• -• MR No. L6F25 • •••• • ' •••• . . • •• • • • rs . - •• ••• ••• • • • ,,;:. 1, •• ,~ It'" •••• • • t, , ![ i , 1<....: ••••••• ;c{ H, r ,., ! • • ,.. I t ., ~ '1 Ii : ! - .:. - ' 1;.~ . Hi''· I,& I llf.. I , ~- ,. . . .. ~ -. (; -.,. -T ,. ii-, --- I .. 1, J • +. It - Ft+i= I, ,, •; : I' a I I It•• l_[t 1, ff+' " 11[ ' . r I ,,_ j L ,! I t' ;• j ",. ;l: ;j. T' ~ ·r t ' .i I ' .. 'i I ,!!: ,,! i ,T· _j ct'" •./ ~f 11 . I 1'f I I !1, ' 1r,, _, , , 1 f I J~- ,, . , ~ &' i f:i& If tE 1t 1i.;: iilt J,' ,,"... ,:+: ' ,- ' t' t ' I > II 'f I " -~ - r- • IT ,:_ ,:r, ' ,½ ~ ' ·I • • ,t ti "' I tl ~ ffi • 1 :t [1 't a f , 1 ia. ,1 _ 1 ~ 't , ,i r• J t l!' i-i '~ I c H : :c' I I. "t' . ,- 0 :it; ti It l..:l. • • .. 1, t11 t' 1 llll 11111 l~t ,, "' r ~ 1, p- • - n,: In ~ i!' I! I I I I:?" I" '" I I t'- ~ r 1-, I ~ I! f I I w :i •. ' ,, + I,\ t ,, 1-, I..!:! ,,t ' ' 11 1, (, s;l ,, h ,1 i"'I IEi, ;t I L' H T IE lff :ci!- ,, I,_; I' Ii I It .i.!: ' I' IF 1 I.I? 1.6 I • I ' li I ,, ,11 If ! ',~ , " ,,:· • ll IJb ll ' ' . 11 f' I • I r - I (b) Landing configuration (split flaps dei'lected 60°) . figure 21. - Concluded . ••• • •• • ••• • • •• • • •• • • • • • • • •• • •• • • • • • • •••••• • • ••••••••••••••• • • • • Figure 22 . - Stick-fixed neutral points of the Republic X.P-84 airplane with original horizontal tail, as determined from test5 of the 1/5-scale model. Idling power, landing configuration~ NATIONAL AOVISOAV COMMITT£EFOi AUONAUTIC$. ••• • •• • ••• • .••. • • •• •· ••••• • • •• • •• • • • • • • •••• • •• • ••••• • •• • ••••• • • • • Figure 23.- Effect of revised horizontal tail on the stick-fixed neutral points of the Republic XP-84 airplane, as determined from tests of the 1/5-scale model. Idling power. NATIONAL ADVISORY C°"MITT[E FOi AERONAUTICS. ••••• ••••• • •• • • •• •• • •••• MR No. L6F25 •. ••·· • • • •• •• •• ••• •••• • • •••• • • • ••••••• • (a) Tanlta ott; bombs orr. Figure 24.- Et'tect ot external tuel tank• and bombs on the aerodynamic characteriat1c11 in pitch ot the l/5-scal e model ot the Republic XP-84 airplane With original horizontal tail. Po•er ott; cruiaiDg cont1gurat1011. NATIONAi. ADVISORY CDIIMITTEf FOi -..uTICS. • ••••• •••• MR No. L6F25 • ••• • • • • •• • ••••• • ••••• • ••• • • •• •• • •••• • • •••• • • • ••••••• • (b) Right tank 1n inboard position; le1't tank ott; boeba otr. figure 24.- Continued. ••••• ••••• : ..••·. •• • • MR No. L6F25 • •••• • "• .... • •• • • • ••• ,_ - • • ! I'- Ii l ,,, • ! t · L J ••• ] 1. • • • " I~,, /r,J:;,., •••• • • . • l ~ .;, I ••••••• • C. i ~ "·- i ,~ p.:. .l v . • I\ . , ' It , It" 1 I C i 4 t,'+' C IL ?'- ~r - r ·l. i ,.. ,. 1./ ~ ~ ·, ' u . I ~ i ~ j h • ' I 'l• :} . " .; ,;:r- ,..... J L I ! ~ r r ti,--' t t/ b ,i" :;-,• 13; ~ ~l[/) it j 'l• t ~ f r lt I t· 'f' tf 1 ~ T :> l C" l1 t, ~ h I ,. i!, j ., / 'l l pl +' ' ~ ~ tT I ~ I ~ t ---- t>-.. ~ l + • It~ •- ~ ., j. .: i, ' " ~ C le i'<1 :u ii tn I '± It J i11 It ! ·fr l"-1 ·• :,' ti ft ! - I • II • 10 , ff . ~ I ", ,, I I f 1 '-. l cc t r"\!l\;)D,_ ,1.r [I') l J r. 'f • ' tl ,, ' . t • I I i _fl IL I IL.i [t r r, r I• l f' ll l + Ii " II l tl • II ,I\.+ I ',t 'I : ~; l t l i J, , !.1 <' f • I~ ll · , B l , n , ·, 1, 1· ,.1 l ., I I l'-l l l ,. " 1-- ~ I .J ill ! ~ > f., ~ I ~ 3. t, I "~ l J !' \ lE£ l i< I tt !. 11 • 1 i r I( 'l l,t ! r,i , J i" If" ,,., ·f ., IE j It II Ir ,. ' :f; I f ![ r; 1, : ' I • ' ,. IE rl,.. . .,.. f. Ii , ,r, , , G •· ;i:, L, ++' 1 ,, 1r ''A .f Ir. r . £i ; ,~ I[!'" i; ft 'J f- 1:tt It ,t: l;r. A iT 11f+- I• 1 1" " 1, } il: :,J i' ', 't X '!. ., I + .f:i i ~ ·-, ~ .,. ' ,. ff ;; 1 1,' I';: ;· " 11E Ji: If'·• " If: 1lil ~ r :j:"' 'i' f 'l l ..t :i'J .~ ' •. iS: ' /; 1 1 ~ ,. •"' J .~ l't.~ , ;t.. ,l ;..J,J lfl , ; ~"•, nil ! " i • .• ll', ' ll\ h II I •· H~ lr : t' f0J. IEc If lfr I' It i t ,,..., ' j ',I I-' , • ~ ;: t· l f , n •+> If [, •, h ,c_ll['l J_:, ,t. 4,.r l, ,t if'. t. 1,1:, ) ,-,_ :t Ii 1 f .l W ,, 1 I'~ · t J •11 : ·,lj I~, , • · t liti rr • ' IE • ;, • I• ' t .,. ' :t, 1! ! 11 Ir !' •., 'i [ I I ' , , , It~ I It ' (c) Both tanks 1n inboard position; bombs orr. F,1.gure !¼.- Continued, NATIONAL ADVISORY C£JNMITTll FOi - ICS. ••••• ••••• .•• -•.. • MR No. L6F25 • • ••• •••• • • •-·· •• • • •• ••• •••• • • •••• • • • ••••••• • (d) Right tank 1n tip position; left tank off; bombs off. Figure ~4.- Continued. ••••• ••••• MR No . L6F25 • ... • . • • • ••• • •••• • ~ ,., • ••••• • T '-.J " JP 'r/1~ a •• • V • • • '~ ✓ I • •• .,,,--; • • . ?i I) ff >-· . - ..! 1---- ·~ 7: • •• ~- v- l1. • • • :r- - r A • • • ~'1"' -i.: ty'.,. ••• r-- i-r., ,~ I! • cE ...... t _ j •••••• ✓ ,- ., • • •·'- i N 0-.. I ---~ I., d, I ,, t L I I~ l ~ v- It, t II j t, ~ ·' ,, " ' ,, &-- f""',)._ 1:. I• I r., I :: 11n + lrri:t ,'.r ir i 11 \;' >-.. j it It l ~ ! F ' - I ~ . µ_ ,. ~ i" f.<-1 ~ ,- :l ;' ii I P...,r:. \:., ~jr.,J t~ '-._,. cc + i ,, t .~ ., Ii ~ I I I:" • ' f,. I ... ' ,, 11: + ,, ,I,f ff •-i' '+-,)'I,,r IF- .• (l iD It I: f',-, II: l ...:- .f) !_t;.: Ir~ ,.. ~ It I ' J r- .... ,, ll i l:t 1-s1~ 1, 11/i ~ : ?: \. ,:..., It I ' - 'A I ·s ~ ... • I ~ :, ;y l " -+ I• ., 'le: ~ ~ 'I"-- 11;.j :, t l.ll\ l:11 I)--' "" t T ' n ~ h:\ ~ ; IF- .. T l tr ,, f If I l.fi t Y"I ll 11( ·~ . ~ ,, : , I-' . l • 1 l If ,.._ ' Ii : + - II ,,11 - t! lit j; ~ I"' ' I• ' . 11 C I!.\ - II II : / J >,:) ~ " ~ ,, ~ II 1: ~I;) f : : ' I ,, ~ [): " ,. .. . If L A ~ l: •;' - II ..... - • € ,,. C ' r ~ : I~ • If 17:i v ,j w t 1 "" ~ r C ~ ..,'\ " ... ' C L..-.!! "' C\ _.,. F' Ii - ..:. ,- ~ NATIONAL ADVISORY COMMITT[E FOi AEIOIIAUTICS ~ - '.J " ~ J ' ' I - f t l) ,d I. ~ ·"'' ' . . I I i, f'n P, 1:i fr 'P. 'n .. {, r. - It (e) Both tanks in tip position; bombs off. Figure 24.- Continued. ••••• ••••• •.. •• ..• MR No . L6F25 • • ••• •••• • • T /+ I- >-- • • I . !(c ·- •••• n- ., e~~ •• • ''-l ' ...... ~ fn, I nf [/' • • • e"- • •• :.J...' [_ '.L V. • • ·~ '-· l-..... - ·~ i- -- - +-· ~ ✓ . •••• • • u - • • • ) 1-;-:; , 'fJ. Pl. M' :t I ••• l l'i:: l)..lY' - -i.: h "';' I • ~ -- - - •••••• - Q --I~ - ~--l:.ii f' t' ~~ ti ~ 'Jc .. l r • ~ >- • -- r.'. ~ ·, . ; . ~ ii,... :r X: -h ' ' 11•1+. .:r ~ ' ; • . \." ._,_, l_c, II - ~ 1, ~ ,'li qh, .1 lti Li H ' 1, I, t i : 1, ~ i I, "G R .': ,._ . r.i . + efl fH r I~ : 4 ii,-, C -~ I--. t ,__ It r t! 1)-;:; ~ u. 1q 9, L·.j, ! t 1,' [f! I-- 1,·' le 12 +·- l I•+ f • 1, j J I : . I, . -'- ~ ) ., , 1, I -- - I ::: Ii ,.._ ...... 1-- (._f', ; If ~ 1, rr. . j 1t'' t. " 1;..- - . > '· i It~ I! iJ r.. ,. ' ~ , I; i '• ( 'i I- ,.. ·, t C [l ,fft f ' 11 I IE I I .. ' I • "" ' ' It• I • 1< 1... ,- ,'. - I+ ' ' ' If' 1h ';' 1 !' I: I l ll 1, 1'...iirf r " '' -: ' 1, I ..... ia;l ,, ·- ,... II. I • I " s: El .:c l, ' I ir., I~ IE: C I j: I l -- I: t - lh ., •.; ,: ,:1 t: I~ i 11 . ~ I r. r ,, : ,;; ~ It·" 1-"· ltf,1 ~- [>+ti • w: . . I t •l t,j lif1 ... T IF l tt I r , 11 f I~ . •.i I>( ,~ 14'1 I , t II i , ••, 1 I~ lE Ir• if I' 1 I\ ~ :r IJ -· t'l 1, -- 'j .. ,, - r, -- J, f It, IJ ,,: ,: ~ I ~ . " ,. :p 1, 1; ';. L. ltjt I~ ,.i l il ~ l I ft le,:, c:r c... lt r -. :t~· r , ,, ,. It IF - ' " ' --., ;:. ij • " I ,, 'L It IT. ;~ :u:i. r, t! !'l • I· l ' 1, r ; lil r- I I"=!{ .I f Ii t; ' '-lie ' ' al E: I I ' : I , I ' ti ~ I, ·~ t -, -~ ~ IJ- ,I ' . ..- r::- I ~I ' ,t 5 " [.. ; ~- - ,Ill - 14... ' I t" - ' I ;' ' ,,.. 1, lil J:ll 1, I , . Ll .,. $1'1 NATIONAL ADVISORY COHH~TTEE FOi AERONAUTICS IL ' ~ • , l .t ~ JI? 1, ... ' ~ ; Ir i I ' ! .J.. • 10 {,:, .. I II r· I li f Ir, Ft llr rll . ~~ I , . "' I ' , ~ i ,. . . (f) Both tanks 1n tip position; left inboard bomb on, tip bombs off. Figure l::4. - Continued. •••• ••••• • •• • • •.• •. • ••••• ..• MR No. L6F25 .•••• •••• ••• • •• ,., I, 1 • • : I ••• t ., I t) , 1.11.,;;,\ j • • • ·,~ ' + I • • • tL 1 . I r ., ·., In ,. ,._·~f>..... ·• :..:.. • •• H rt- Ir f l I+ ' r~ I : °U'-1.:., ..... I>• ~ l.A- • • . :i: A ..; • I 11 ,, 1;::- •' cl j ( Ir. , 1 ., ':, ·t. ,i,.. ]: Ir~ -l:. 1 • _ / l'J -~. i h t,. '+ ' .1+ ., .~'-). ri _ ... ,, , 11 t ., 4 ~ :rf:t ..~ li 1 It ' • + 1· ·~ • I ·;i. 1 !:i · I~ l ~ j E l , t,, T ,,, ;.•. '':. r ri7 -...:;:h_. .; - 1- ,~ • I I I f I -1- '• ! ., , :::i:11 ~-u I 'I , , ·• l f ' " :. ' ~~.,c I• 1, F ' II .r C ~... ~ r T ,: _, I• H ' • ·> ' 1 F t-+.,.c+-+,+~, t~h1,-,+-t, •~~ t-t~·• --ll~~~-+.,,+.::+-+~--..:.i'--1-U I '• } 1 r;;tr:tr-i"'I1!:-:ht:-+:+rt:-4--'1~h+-=+-+-+.-e I:,: 1 !hc1-!+-t...... l..:.Jw' r t ,,, l l 4- '+ • , •' le t +, ( 1 ~ 1 H , t;- c • .. ·: ~ , 1,i ) t I= t ) r l , l ,,, r ' "· - I ,r l t iSt Ii G [ ,,-+: ":fl'. - .• ~ ,t • 1 1! ., ,, , ., J• ' ' . l (g) Tanks off; left inboard boQb on, tip bombs on . Figure 24.- Concluded. . • ••• • •• • •• • • • •• • • ••• ••••• • • •• • • • • • • • ••• • •••• • •• • •••• • • •• • • •••• • •• • ~ z 0 Figure 25.- Effect of external fuel tanks and bombs on the stick-fixed neutral points of the Republic XP-84 airplane, as determined from tests of the 1/5-scale model. Power off; cruising configuration. . . , ..-." . ..• -• / • ....- • • •• ~= ....i.--r4- . • • • .• . . • .!. •• ~ --· • . r:ml:.fu = +< .-~.J -v•••• - ,·,.!,.._,..,1,,1 . - /• tr! • • ~ 1;., 1t: ttfJ ::W rl:lli - . cl :fffi [t th ttl! - -· ··- ~ . ~· ~·-·1:1 -i;j , .... - :c :::,r,-2'i~ - l .... ~ . ~ :tl l ~ - - :1 .. j c+-: 4;.tt l;l~ ~ l I I ,_ T :~ ...... 11 ..., ., F.' fjj: :Hi-I ~- - fl::E ~ - ..... : ~ 77 r~ µ = ..- ~ cc . ~ -li .,,, ·'-14 ±! • . ., :t:1 -·- -;1 1!:t - • i:i: - ,.... • . ~ C!::1:1 :!:! ,:,:: :tr tt1 :ti .d :;f --:. .:r H , . t:.~ ._ .--,- -: r 31£1:E LI ,::c ·= l il r= ,.,.,, ~) '.1 u~ - - - ~,.p - "' fT; • ~:!j L • ~ .•. . . :lttl :t tttl :;":ll !1I': IT1 .t11:1 ~ - ti ti ·-· t.r. r ... l:t,...u ++ NATIONAL ADVISORY i COMMITTEE FOi AERONAUTICS ~ ~ ~.;.. .,....,., ~ ·~= .i.'" l !ll . .:fu l.±1 :l l IE't1 + = tH i• ,._, ... - -.... -- - i:,:i:i ml :m c;:rn ' +,-.. ~- - 'l ::HE= -:-i• ...., - ± "1 .-...1 ·~ ,4..U-1 -- .,.,.,..,l"'T...... -~ -----• -- ~ (a) Inboard tanks. Figure 26.- Effect ot external fuel tanks and bomos on the lateral-stability derivatives at small angles of yaw ot the l/5-acale model ot the Republic XP-84 airplane. Power o~t; cruising conf'iguration; it= o0 • -••· •••• • • •• •• • •••• • • ...... MR No. L6F25 • • • • • • • ••• • •••• • •••• • • • ••••••• • (b) Tip tanks. Figure 26 . - Continued. • • •• • • ••••• • ••• • • • • ••• • •••• • MR No. L6F25 • •••• • .•• . -.• • • ••• • •••• • •• • •• • • ••••••• • (c) Tanks and bombs. Figure 26.- Concluded • .. ••• • ••••• • •• • • MR No . L6F 25 • • ••• • •••• • • I •, ... . ~-, ..,. •• • I , ,., ... . rr ~, 'h Ir, l<•i Ir • • ••• ., \. I "- :J "'"· • • J ••• ~ • • • -~ I ••• I• ,_h ,1.1"1 1-Y 1t ••••••• • ✓• . '"' l • • ~ CL., 0.2, at !0,000 ten I, -~ l~v ! ~ '--.,___ ,,..- >/ :!I i.,-. "\ (:J (~ y. r ~ '/ fJ -~ .._ ' :'I: " I -1-- bJID tull- - 16,0 10.8 57.S ri itc I r IJ liJ 1, j 'rub .-piy--:56.t 21.t !, I")"' • I i,O -, Sl,l i r'c· ; ~ I, ~ ..., .... , in ., . ' . ·- .... ~ l'1 '" i , :,.,. ) 1, I ,; .. J y' L' ' 1, ,.... "' .a ' if "' - I ·'-" ... ''-' ,t . I . ·t I, :t ' ,_ . Ir - r ' -1.r ~ 1--, ..,,.,, 'rf7 l - V\ A J / , • IJ ... ~ IY _.,., l'T' ,:'i ... b ,,, f] rr . ,,, .,_ ·r j 1...-r f-11 .i,,,t if) j . .,Y' , I" .. ~ -,.., rf"T IJ<' l , ,..., Ir- , "' f,1 :[m l, t T h y' .,-, ' Ir . I '.JI ) . ,, fl •~I 1/'l'i (} I~ ,i' Ill 1/, ) F ~.n1 !?, ) ,fV ['1 :J• I: I T ~ ,, .. IE ' ' r - - 't ' ·r I l f ,.., J -c.. ~ I· ' I b J ' VI CL = 0,80 al 20,000 fHI rl ' J I\ _,_ fl t ~"" (:;Y (~)2 '1 V .... ~v - o~ ,,...,, , .. ., ·- 'rUD full -- 16.O 10.8 s,.8 !: • ,' Iii! 1,1(' ,0 0 I I-~ .f. ~ ,n, Iv' 1, .. I (U ,., If\ .. ., I :,t< '. n ' LJ.- __ ,.._ I V ... ,oJ 11.J- ~ ,.,___ - ,( NATIONAL ADV ISORY ~· iµ.- COMM IT1U FOi AEIIONAI/TICS IF I..« .I ·L.. 1 µ.; . ' ll. . , ul. !).I 11 .~ L,:.; :u... .- .11 It 1.· ' ~ ~ ' I I 1/ ~ /), )( q ff}, )/:) !fir' )/I ("ii 1?') VJ, if .r ., 1, I rtpre 'r1 •• -,,..,, ot cattTi.ac tuel ill ill• willC Up taau on ill• 4TUll1~ lden>.-nalltltv llomldariH of Iha XP-86 atrplue. entetac oold't,uzntoa, ...... ' ~ •...... • . MR No . L6F25 •••• •, . .• •~··· • • • • ••• ~ . • • • •• • • • • •• • • ••••••• • (a) a: • 0.1° . Figure 28.- lil'fect of inboard fuel tanks on the aerodynamic characteristics 1n yaw of the 1/5-scale model of the Rtpublic 0 XP-84 airplane. Power off~ cruising configuration; it : o • • •••• • • • ••• • •••• • • •• •• • MR No. L6F25 • •••• • • •••• • ••• • • •• ••• •••• • • •••• • • • ••••••• • (a) Concluded. Figure 28. Continued. • •••• • • • ••• • •.. •.. .• MR No. L6F25 • • ••• ••••• • • ••••• • ••• • • •• •• • • •••• • •••• • • • ••••••• • • (b) a. = 8.7° . Figure 28. Continued. • •••• • • •• •• • •• • • • • MR No. L6F25 •• ••• •••• •..... • ••• • • •• ••• •••• • • •••• • • • ••••••• • ..; (b) Concluded. Figure 26 . - Concluded, •••• • • • •• MR No. L6F25 • ••• • • • • •• • •••• • • ...... ' •• • • ,.,_ • • ,..._. 1-. r A ~ r 1 i - ,. - • •• ~ • • L . , ~, • •••• • I "J\ • • • I ••• l s: 'I J -;:: • / ,, ~ I. •••••• 1 ~ • • l . -- ~ . ' ' ...,.__·-- H , ' t. t ' " '"~ : r'- '-71 . I 1, (, .. ,.,, ~ . I I " 'j I ~ L i 1 "- ' lq ~ ~ r .., '> • ~ ~ --~ ' . I I 7/. t>): -},,,~ ' 'j l £ ' .;'\) ~ i3 t I ~ 10 In ~, ~ i : ~\. __j ,, [i] /) '? I 1, .I.: / In ?) •f- r ... ' - I: - ...... 1f "J ,- 0 lh; nn ' ' r 11 I J " ' i;:: _"- l It· l ... H I ' ' ' . ._,n l I,..«. r - l I I I, ..J ft: ' ' C ~ ' " ' •' I ,~ ~ tr -1 1:· ll 1,,± ~ ,tj-' j ' ' ~ 't -.. ,, ' . ,' ,..,.... *' r I ".!, .I l f 'ij !~ g_ 1.; ', ' I -~ '". LI ~,: ltl'I; .lj £; ' ,_ ' I f ~- 1 1,,-W I'' 'h Ii I .,. f(" _,..., ....! .. C 1 r- .... ~ t r l ·1 I ~ i;: ' i. ' ' f t, >-• f r: l ,. .. l H l r -~ I I ,. A q f ! .i ,. I f 1:~ t . '-- '' E' . 1 I•.,• -- ...... - ' ' I ,. j I I ~ . 1: d __,. t I .. I ' I ·' r::'.l I 1 ...... ~ J l.!..() .... ' .. ' ' r Ir> L). t,,v ' 1:: . '--,~ 1-# V ' ,, I Q. "' ~ f( ~ t"",:- I -;+ I I !! f:: t h If J, tt t ~ . I ~,.,,, Cl ,. j I/ .:J I ., r > ' - ,_ ~ ,.ir,,- 1. I I l ' t' -~ t- fl ,, t r •' 'I " 1,--;:: t .H !Ct :;. n . f J I?' I ' ,, • 'I., ..... , y [:..,' l .J - } 1 -, ') ID Jr> !,- '1 ' - .., . ' rt .,, ,..._ ~ J.n, 1/t:. r-F- IJ.t: 1//J lJ/" A~ :, I - I - - - ·- ~. NATIONAL ADVISORY (a) CL . 0 . 1° . COMNITTU fQI Af-AUTICS Figure 29 . - Effect of tip-mounted fuel tanks on the lit:rodynwnlc characteristics in yaw of the 1/5-scale model of the kepublic 0 XP-84 airplane. Po er off; cruising configuration; it • o • s : : •• • •• • • •• ••• MR No . L6F25 • •••• • •• •••• • l •• • l - I • • • . ' • •• + • • tl •1 1> ~ :· F i l !~ q, 1 : 1• . ~ ••• rr ~ tl t ';c I.' ,,. If .t i.' i r,n: •; ' J • • • :+• 1:,, :,' ;,; ,if' • • • r, ' ' ~1 l't- if !f'i Jl'.•~· "·c'' ••• 1,' 1 ,~· p :~ ;.. ::f 1'- J I ' .: • i . ••••••• ~ It IE h • 1, , 1, ' . c r, l . t I I: ..:. "J 'l ~ •' ~ 1, ~ ? t,. 1:t tl f ~ ~ .t- •· > ii • i 1: .:,\ .., i i' J r :a r it~ "l ;1 ,,1 a= r ;, 0 1r j +I ' ... ' E L• Ir 1 ; ,,, I ll ,: I:,·¼, J• a :l m ' ·' I ,. ' f ~ E it' a ti, •. .! It j.. I•· 1•· 1 •i '+. : ., I ·, :t +I ~- . ' r; I~ IL I' tr +- I<' ' . i ·~ T ,.. : L u •~ I;, : '\" i l n -,, t '£ ' I' It l> Lt ,, 1, It - . ;/ I' IL ~ T . f " Ir\ ' ; HJ t If ., ,J ' .. : I rn- i t l 'l: l+I c : 1 r ., t I ~, ti I•~- J ,. f ,., • I ,, C ' • ..t: .f ; +\ r I\ ' ' I IE+ f i"• ,i I ~ ,_,,, I, ] L ti- ,~1 c<· !t'' Ir lirl- E ::.i t ' 7 1-'.7 1/r S It ' J e •If l I n ,. i ! ,, I'' I ' f r '' ·- If .,( 11: I• " :r1 l '., , 0 ,,_fJ f 7 ... ' ·- ' le ll " r, • ,'7, , I'. In ' I\.. I • 1.1 1, I . tE - ·. 0 •I ih &f 'J I I f'.l P? H ! : ·. . I! 1-f.. t' IF ·p•· - L t. 1, it ~ ., j . [ J t· [c< r~ f' r ,. ' r ' ' J ,, L .,! .,t. ,. l l l r ,t ·ttt r I . I; • ' it l , I h· : ;1:. t ·, ,,. it ' ' ., ' f ,, "f lit I I J i f ,, le ': It ltt ' ½ TI Ir fl ,. ILj ir ,, 1:: p: it I ,I ~ . : 4' '\j lj: + " J" ., It i~ - 1.: Ii., : tr,, L It j .' : t ·~ lj: S,. l'i ' . -· - f t I i I~ tt l IL ~ .. , .. - i: ~ T h I,~ I t' .. ,. ..., [ r,1 1, ·~' J ! ~ I : .... J :' 1 ' ' 'f t CI .F ' ,, - ~ J ' j ,F' 11: 11 ., t/ j: ,, r •J ~ } if I a 1, :-t' 1, - Ir ' i .\ '", ja,J 'I +- Qj.l" j lh~, 1 ! I> j j3 ~ I I~ I J,1 "lit ;+ :,, Ii+ t Pll t ,f. 1, L t I>' ,~ . ''" I t .., • fT ,,;; .,- ,L ,. '. : : ~ • t. I "l • : 1- l ~ ,TI • ,,,i . ' ' t I·' t lif, If It II , 11 l t I ' If . b .. Ii-- ' i, ' r t ~ n ~ - ...... f-J , --) ht! • -r () r ... (} m I; /I') 2'() + I·• I• II IL • + ·, ,_ I~ .,, ,,.. - :t II I, IL 1llA r, i<' F 111'1 Ill ')Jj l•t rllM ,~ • [V I " [;T l 11, I I Ir -, ,,;· NATIONAL ADVISORY .._ il l ' i 11,i r COMMITTU FOi AOOIIAUTICS (a) Concluded. Figure 29 • - Continued. • •••• • • • •• • • MR No . L6F25 •• •• • • • • •• • •••• ,, • • : + ••••• 'l 11 ,, . J' • c ..... ' . It It " 1-, I •• • • v r • • • ~ ~ I.:... L.c ,._ • •• : • j - ~ IH , , ,,, • • I! It~ ,, t. IE ••• '""J '\ J. l • • • 1, • • • t: I~ ·! lr,- ir:i l~k t . • •• L '-' . . '" I• J ,, ... I . , • 1,. ,,.., ., 1·, ,~ t; It i Ii 1,1 t , • i h ,t t .. ff F ••••••• • .1 i l - I\\., I~. If fE( 1, i , , ,., 'l ,ti,:,_ II i j 'l •j I' t 11· Ii, I I Ii' '\W,_ 1.. I a! fl B'. l: I~ 1.J. :~ I'+ ': IJ:t: ,, Ii I, If"' [[.r' 11 ~ I '1. ,lj ;ti· 'l It., I, l ,! ±'I, la : ~ ~. for l'N ,r! ~t. i J' I " 1,, ".., lj "i 1 ,] .~. t'N: j '; +1 ,.l: ,t. ti· ,I,;, i 1,1 It' I ~ + +, + + :- l•tt , ... i t 1, ' 1, l e f~ ~ 11' Ii "'+I :~''i'k' IE ~ ~ ~• I .. • I'> . 1 f\ • , ' ' . L "\ ,, ;. . .. It _ r .r:, 11 ~ . ~ t al ~ I, , .. • I'-- Ir ;: .... 'i l .. It µ IL i• ...... + ' l ! , ,, .J~ j J IP f'~ ll ' ::;: 1, ·· ~~ ' t -ti: l r If :, 'L:,_'I j 'f.'• ' : 1, • ., It, , ·~· Ji • '" r-,.; .,~ ,, ,,, :1 •.;. :&- :l , """I l + I "+ ~ :, 11 ~ :, ,,.. .1 It I 0 /'I l,C1 It " il riJ 1 ~ :i J "' , .. ,. Ile :c • I'-' -, Vj ,f /I 11, 1 I • El Y' n t ~ !ti A Ii .. , .. ,., ;,; ' :\l :, 1, It 0 h. 6 !t .i .--.. j ~,~' ; I, '1J . 1, j .. I . ~ I• f ,, ' I •..; L, _v' ,__ ' . 11"'1 (. J ' I 1, • I' - I> I/II I I~ 1 11 , ~ " :1, t t, f ll IY . + 'Ii J ;. 1, I I I ... " • ir-': ~ I 4 11 l 1·~.# ~ ll t1 ., 1; lrl ,I , .. I If l Ir I It ~ a l,, {T ~ t ft :, 7 " 1 1 l ""' lj I 1 1, 1 ' IJ',, ~, .1 ,;, I ~ It -, , ·i IE L '" ., 1, " le I t I j ~ :, l..l :l't 1 I, i: 1, ', ,i '! f. '" r ", ti l "" .. _j y; L i l I ~ I l ' j tJ ' t .. ~ :, j :!' J l'. ,~ l t I .... .:! t • i I~ l ,; •; ~ .. :-i' I> :1 . '- ~ . ,.._ ,, ·+ (• :, - >'! :rt ·r J l > '] t: ' 't .. 'j r f ,, p --,, " ,, .. J - ~ . - t --< >' - ' + t' l' i: :'- ,_ I './ ' / ' f j .t I ' ."to .. ' '). , ,! T ~ ·ti -, ~-.- .,.., 'ii +- P, 'if- C ,, r" l ~ I ~ I~ l T1 .• 1 .I . :v (~ l " ·~ 1 1 - 'Ii *' L .f. Ht I :!,,(ii J.,... +j I C , t:" ' l t: 1:• 1 'l ~ .. It, "t 1aJ:: Wt ·/ :r I [Y .t .. . .,,_ .~ I i I• ,. 1," V JI l •!:'. c~ l ,j ·.• 'I • ' {r. l ; i,- 't- I . ""i Qi'( : ' , r, J t J,. re . I + ' It . \. If • .. '..,,, [ .....l . .;: • •• 1: t 1/) : ./ 11 .. ,__ " ~ : f'- ') [)'_,, r:1 ; ' L , . ,. .... ~ . l:e . I)"'.'. ,'.) I)'!' dr It. ~ ,n "' - ·~ . 1~ . 't I : .+ "1 "'- r1'f :F I;;,:' jt 1'1 1/itt Ir· ,, ,, ' NATIONAL ADVISORY (, f , ,._. , : COM MITTEE fOI Alll0NA\IT~ tt I: "' IL t; I: p If:: :~ 1: ,;: rY 11,. Ir I,~ 1 t . . 1"1 l e~ •·, I , • •· j 1::::: • .. V ' ,, J f.:!i, "' 11,:: ...... ~ ~ '/ I t. ·,.. I,- I I : . ',If t!l l:it hf ., • v:--- 1, : ,, 1.4--! .. I ..;:.~ () .,.'j I') I n ,h ,n I~ r1 1; ,_ c j , I\ +. :~+ ,~ Ann ~ ,,,, './JI II ril, I ii] .,,, . .. ,,, , .. I , :, , ., ' I ~ ~- + , -~- (b) a:.a.7°. Figure 29 , - Contlnued. • ••••• • • •• • • •• •• • • •• ••• MR No. L6F25 • •••• • •• •••• • •• • I• I • • • . - • • ••• ·- . . 1, "1, . .. • •• >- .._ • • • ' I, 1, •· ! • •• I'- ,__,._ • f- '---- 1- - •••••• 1-+-.I' + ~ • • J . a' i i r, it .\.. .. -, I cu . '·~ rt .,- -- I, ,. ; l:t,-: ·r .,t L ' 'la Ir· i I'. ;. :, I• Q I; I IL t; ·~- ' :, Ir . C \ i 'i .. Iii ~ ~ '{ ",'," r.,; Ir 1-h 1,-, Ir It I {I f . . !f- [r I ift ;I--,._" ·l ._I--" •' I . - u~ . it,:' IF I r,- rrn l.._- ! ' ",. ,i I• I " ' I t :t •J • ~ ,; " •··· ~ ~~ . 1, ' 'f n ' ' .. 't. Z; I]:: -1 7i' ,j., :;- -. '1- ,... IE IJ; ~ ' /T}; •- -.:; . iE I~.- 0 - ' '• . .. 0 Y' .',n ~, ,.,,., ,! -~ --,. >---- ..... >-- >--- r- 1 " 0 J. 'f,7 ~ ,., '7 1, j ' I ,.- ~ ' :r ' - - ,, 0 I . --t---f- ~ ; r~ '' r ,_ ' . f ! ' ·,; '1'. "'"' ,-.:'' " y-- e ~ 11 t ,... ~ I I l l 'ij ,,~ I : .._ - .,., - ' ' 1 ' .- I !i; I + , ,c 'j ' - ' I ' I~ t t ~~ ' I: ~ I - I<._ l 1 I J I l• : h ~ ~ ~ 1 I . I I-, ~ T ' I,~ .... ,, ,, 1--- ~ I,-- • - I - ·------ ~ !A , 11 ,, \ lti" •-:i:, ' II ·- • ;,Y) ... ,n · I) ,n l.?h t---- -.___ '-'-'- ·-'- I : , _,. 1, l In, ~l.d I l,c V ~/J 'l ir' ~. H-- >- , " . I , ~ - NATIONAL ADVISORY 0-- i ·,1 11 _COMMrr:m. fOI ~~UTICS I I I I • (b) Conclud d. Figure n.- Concludod. • •••• • • •••• • •••• • • • MR No . L6F2 5 • • • • •••• • . T .•••• . I ~ •• • . ,,.. i r . ' • - T • • (.•~• V : ;r •• •• • l:, -- ~ ... I J ,~ ,- ,.._ ••• ' ,- .T • • • ~ • • • I. • •• r, l") l I -~ • + I' l • •1- ... J ••••••• • ~~ \. 1-r- . ,i_ 'Li I J' _ 1t l1. , • : :t g I i : !, t h : T, / ,;. r ~ r i " ~ , J , ., ,, t , t'• .., 111., , T ' [ E ~~ , r · [,: I , I I :I Ii. r, ~- ~ , ' IL , -!LJ II") .. '.• ~+ 1i f C C t~ f ' t : j C l f . :vi,c;. -. l~ ';f ctJ :.: F 1 :t ' ~ I If . 0 f-.r,r.k~ 11: Ft. I , 1lf.• ~- It i C n It ; __...... , [E m lh ~f;, ;r/J < ,:. .;;· i. ~T~ ' ! If ', I' IF 1> -...,, ---, • T I ' I ' I f L 0 h >fr> LJJ. - - "JI. ~ l t1 ·:: _( I i-4. I' f j ,. I 'j n. Vl'.:/"(. :V,;'n) t~ I : rl· i;: I T t F ' 1;, I :it f II :L ' '" 1, .;,· I' IF, 11 ' n ' I 'l I t ~'. • It I 11 11 1, r ,_ f E Ir • ' J •1 1: il [r r • l ' 1 l'.J.I 1 -,... .. (1 I L· I ., " r ~ ., IL .. .. ri:..., " I ,r. tr.! !• J 1r f .,. p l I' ' ,, J ,.... , ,., C L ..... ' ·' ~ ~ l t ~ ,. - ' 1< >L: Vi f..,..,..... 1 l, Ii t: :, h ,v I . I J~~ Iii + 11 w It• ,~ IE: I T i IF . •f ,fl I' f' :F I~, " l.i 1- NATIONAL ADVISORY ~ ~ COMMITTEE F'OI WOIIAUTICS tr ' ,,v I [I 1, : II ' ' ·, ' '• l J ~ ' l I 1r F • 'P) 'r""'J () ,n ,~ l ,, cp ,, :t ' ' IA 111,,0 n:'°" ,1n.u 1'" •rtir>o ;. ,. ' ~ 1 I ; (a) ix~o.1°. Figure 30 - l,;ffect of fuel tanks and bombs on the aerodynamic chara cteristics in yaw of the l/5-sca1e model of the Republic XP -84 airplant. Powe,J' off; 0 c ruising configuration; it - o • •••• • • ..,•••• .. • • • • • MR No. L6F25 • •••• • ••••• • • :, I. F+- ,l ••• • • r;,, f" '· ' • •• t II • • ~-· ~ I ~+ 11 ll ±! f it' t j ,!, ;J, it., .. ffi ;t ;,br "" 1 .. ••• TJ t ' ~ ~ l r j :-' +j ~ ., j fl- • • • ,, J L ,, l •••• • • " .. ~ •tl ~ 'Et 'UI• flt i'l' . I I '"- {a) Concludt:d. Figure l50 .- Continued. • •••• • • •••• • 11- MR No . L6F25 • • •• • • • • • •••• • ..•••• • I I I •• • I I I • • T • .. , l!: ·- •• ••• "' I • •• • • • • •• ·' ' 1 ••••••• -~ . - ~ '·"' I . • • :"r l ' < > " 1 -/ ' ' 1 1, ,, ,, It I s ' ,(..-~ -1- r · .; '"hlimh ,,.,,. ' ~~ ' ~,..., IC--1-4---+--+--+---+--+-+-+-- E ' I ' l::B~~ IL\ "" 1-!l ,~ t•J i> 1.. - ' 1 4' t I ~ \ if f ' > ,, ' I 1, J b It I ~ l,:t~ CJ .JI; I=-. h ' IC I , ... [/ . l t ,V I ~ IE ' I l~" I' t ; ,. ;r .... 1... ~ Ii I " ; a' ·: ' :.H I, ...... _" t It -~ I. i I J. I I<, ,, ., ,, :.....: f. )IJ I> 0 .,,. , ,., IJ , , / : L..J ir, t ' ~ r I ~ I '.., > I - ll 1, ... t;:ij J .a, I ',, j~ l[ . l , IY v'1 .. ./ ' c:: " I L) NATIONAL ADVISORY COMMITTEE Fot AUONAUTICS 1 !A 7,,j.J,e. , !> f' llhL U 11/J W.:tn I , . ., ~ I ' ' ' I I {b) a~ 8.7°. Figure 30. - Conti11ued. • •••• • • •••• • • •• •• • • • • •••• MR No. L6F25 • •. .••••• ••• • • •• •• • t· •••• • • ~ • • • u ••• f r • -r - ••••••• • \: - ... . s - - .!c -~ ;, t l 4 L ,, ,. I I i.' ' ! ' . ' " fµ .,_ ~ . CL C ~ L r . l ~ I rt t ;J t ' ~ : - r I : I l -..; r f j " C -4 p""' l ~ •· ,_ ,, u t 1, ' ~· E • , .. 1,' " :· < ... , - ' I ' t ! .I/ ' ~ t,'-r, I.J=t I, l _Q Ii s 0 1f7I '"' - ·iJ ' : ~ 0 f i-n 1 In ., ?J. :; hn IQ• 'f't ~. .,_ •' I f: ·- .. n t, 11.._ ' J ,,.,, ,,.,, Q • ·,, t 'n J.. -- ,. ... J. ... rl Jb-J r 1 ' ) In Vin 'yj >~;. .,; ~ c ' ' ' r.. n L . . f I" ,t ' - ' I ~ ' I j ~ I i - l:l 0 ~ ' ·"- ~ ;_e,'±, ,, ...... " r .. . - ~ .' ,, t ! µ f ... I • ~Tj Fi r;t L l r ~ : I t] L l f, rfl: [ i ~ ff ~ .,.. -~ ' j j l 'I ~ J . ' ' ! j . ~ I (-t I I ~ -i' .. • ' ;J I. I ' 1, I ' I ., ., ' I , I I ~ 't ~ f I' q: L l ~ > ' ' [ - ' . --..J r I ' ' ' ' ' I l. l l JI ~ I I i.-- ,., r I I ·' r ·t ! f r t t ,, • (j._ •J I i 1,·• L !~ ,._ C \ J ,, ,. l, ~ ! I • 'I' ·-·1 ·:: ~+, l ~ ' " ,t ' ts ' - ... :, I I , ' ' I J ti I(( TT I l [ ~ ' ,' L, .ii d • "t ;, 1 I, I.' r-- ... rt. I .. 9 f) I) f) ' ' ~/t') /t:l 12 . I ,.,-~ I A V7 l,t:, l'l,, w: ,m. )/J d 01. ., f , - ., > ,/ .! . t . ft NATIONAL ADVISORY CON,NITTEE rot AERONA,IITICS I ., I ~ F' - .. (b) Concluded. FiguN 30 ,- Concluded. • ••••••• • • •••• • • •• MR No, L6F25 • •••• • •• •••• • •• • I< • • • 1:.t- n • •• I' T •::i • • ~ ,. - -- -~ • •• ,. :t ,,1 • • • • ,I ;t ~ . :t ~ t 0.. ~ ~ r ••• -- ~ . 11 1· ,~-- , • f- • g ~ ~ . •••••• ,....., ,,. - l (:,..__ • • ' .A '+, . ~. T 0 n ...... ,1 ,,., c (j:,. t u t 1 It ~ ..,f'\ 'I -" I'. : (4 .,j I . ~ Ji., ·.; 1,;::- f It;/ ~ 1 { f " ~ '' "' F- ~ ~ tr•" ,, 'I.:. [( \ ', f ~""-, ,, :r.- t Ir . ~ ~ •t ift ~ ~._2: ,.' 1 r ' I•~ µ1 [. 1 ,. ...,::).; ··1 •· J.:.. ' a l .... v) . t' T ' I I l ·1n J,.;._ ;_ ; ,_..,...... ' • I ' .., fl} J I> I ,;c. r--- T I( - , fl -I 11. 11 lci ~ fU 11 l :' II T 11 Ir ~ I~ r--. ,, ,.., ~ _,.., • r-' IV 1, Q 'l - ~ <..: ~ . -~ I ,t 1 ff I 11. It l, : t i I' "\~ 1 1 ~. 1, If : ·:=: I, II I It If I" i....::. f .__ -· - ' ' I• ' ' ·"' ~ ( ' I, ~ . '\. a:i ,...... - JI;. ~ t !SJ • I ' . ' IN• ~ i 1, I t i.,._ IF l I L IE T I t :!1.1 If Ii 1 ' ·'~ - . i,.,... ,....,,. ! l !Sr. ,..,.; ,- - J < ~ : : "" I t ., ~ i: I Ii ~· - 11 •. ·Ii. : r . :..~ L' I ' ii . I I '-' ~ •!.. . I ,-t It J " I • . .. lh l I' ~ : cj!> I c, 1-. 11 \: I ' .,. , r. [ I IF ll It t ~ .. II 11 C . a(: IT · . : [ II • . 11 1, " ..,IO r It , 1--;c ~ 7 I r ' 4 ~ I . 1..: A V"' 1, e;;, I ...,h ...... I 'T I~...... ~-~ "'-'- ~ J NATIONAL ADVISORY' COMMITTEE fot AERONAUTICS lo'.: ' b I "G •~ ' ' -.1 0 ' 1 ·., l ' I. 12 .. I ,-,-- I I ?~ "l)P1 'f'Yr. Ii:>, rt I: I I I I I ,- Fisure 31.- t.ffect of stabilizer on the aerodynamic chdracteristics L~ pitch of the 1/5-scale mode of the Republic AP-64 airplane with revised horizontal tail. Idling power; cruisins confi&uration. Two rockets beneath fuselag • • •••• • • •. ••. ••••• • • • • • MR No. L6F25 :•••• . : •••• • •• • • { I cl: • •• ' ... ~ • • ,' ' I ••• ~ . ,__ .I I • • • ·- -,- -- •••• • • -;-- v- :--.~ • •i: t: r--- irt.. •••••• ,, i A v- -.. ~ • • .... u - .._ ... ~ !'""-n: i .. •. L -:- )" t j ,! 1-..... C < ' _ ! I t· ' !~ I • I Q I' r-,J. 'P, 11-,.,; ' ; 'L Vl ' - r ~ ·~- ..... I._, ·:: £~ •:!-- ~ 0 n r;: Q ~ 1;._~ r h- >--~ El l'1 / ~ 1-..... ll .--r: n I.A (I " 7 •I-/,, } ___ .__ ' If ,. 'd' Ill' )7 I lh r I• 11 ' ....,Cl' r. 11 s: ~~ A •' v~ :__~ Ir ~ 1--r l:X t. I • --- - .. ... •r -~ I• I il'P -,., :.,, s -r ' :·ri..-- ( lrt I) II V ·- IC ;V : ~ V I< - I l J l':7 p / It 11· , .. " V t'o " 1..9 1, ' µ " r,.--- I/ r, 10 a: (J I"-- r / I' It ,, If ' II - ~ / I~ ,..,, J t 1.-4(" v ~ / l u_ f ..I I ~ J~ ,-.- V ·-c-- . Ul - I") ~I> .... :J-, I"" / ' )P -!4 J "" ' ; - I nif . ,_ .1 - 17 d) ') .1.1 1 --- " - '• .. . • 16 I r - J i, ~-t r ·~- ·-Jp, ,,+:, r I I I I r ... I Figure32 .- Effect of rockets on the aerodynamic characteristics 1n pitch of the 1/5-scale model of the Republic XP-84 airplane with revisw horizontal tail . ldling power; cruising configuration; it= oo . NATIONAL ADVISORY COIIMlTT£1 FOi -AIIT"'- ~ - .. . •• •••• ••••• • ••• • • •• • • • • • •• • • • • • • • • • • • •••• • •• • ••••• ••• • •• • • • Figure33 . - Effect of rockets on the stick-fixed neutral points of the Republic XP-84 airplane with revised horizontal tail, as determined from tests of the 1/5-scale model. Idling power; cruising configuration. ••••• ••••• :~.... MR No . L6F25 • • • , _, •••• • I,' r 11 1, • • ,_ ' ~ < ,, ~ H •: • • u ,, ,f ., •••• : 1, ,.,- l 1, : '" .' . ' lt l e: ,J Jr, ,,, ' I, •• • t 'f I • T . : L I : • • • ~· : t . ~ ' IL : ' + I • : L • •• I: r ...1 I I • l 111· • • ~. .,. It --~ I 'iE. C It . .,., .., --; lfi •II 7 -- ,r It • •••• • I ' !t iq._ 1 ,:- . • • • i + I.' [!;n ;c S" ~ ~ Lr.I. u l .• L ' It T. !i !t d f -~ i ! ••• r., ., p j + ~ . j •f 11.: I> l .... , it.. . i • ~ . r.=: - 1 ' II l ....,_ ~ { r,, Is ' ••••••• • ~i '\J l: Ir '-I t ! h, t r,-ltl 1,• r. 41 iTI 't: ttfi:, th~ .,: .:i: !&1 ~ ·~1 • 1~. hJ:i ) ~ ,r 'fW t + lq 'tf IIJ: ~ w·, lo! ::t,, ID ~, k• It-ii I~ , - -:-;, l,r +'• (§.~ ,F lf' t c1 F.'f' d i• Ii-. "'iJE+- ' ,1; lo# BJ [~' It : 4 !Ii 11 l::t II :ihl [;J -- 1 l ,,, B- r, :l'fl< It!' lfJ:i: IH 1 ~ l" l D I 'l• ,..f It i :t-1, 1.-;'. ";; ll'f- . ~ ' tr,... P1 "!Cl.. .,.. ,,.·4 :J:t, ,...-; ~2 :i_, ,.._·, ~~ ~c::s Jf, l •~ ~ " tt£l rf J' I :~ lr'l tt ' ·~ :? -~ l-4 lilt 4<1 -41 .f tf f. ., ~ ,.~ ~ l ;1· l 'r l•it, 'I ) 1 i ,., .1 !F,-1 •;: Ii t:,, '[!. .;+; ~ ._ •J, • ,J:l ' ' i :t< Jt I '1' # t ft- ,_I '• 1. l:~t ,,. ~1 ' -::i s= !;Th 'f [rj l t r. I '':II •I ! ,-j: 18' ll ~ ~ ~- '!: f c i. ~it 'i t f .~ t-• t ,-:. : " c :t t- '; I e, I •.µ tll [+ i.l l;;;c l lf tr I~ ? I ' t :5 'f' J' ~ H q. [tij 'i [>,j J ~ .J [ ~ •l lit, H t ,q, ,J: l=!' f :, Ir- i: ', 'rl~ ' 'H r: hf ' . 1:.i, L j cr'j 1:i' -~ l '. ' r r I " f " l.i:. • J '/. El ' 'I: ',~ ' H 1 : r- I ~ t ,. Ii' : !t J't i f t· r t 'I f ', t"± t,. JlJ,: '; t•'+I f r;: .. ~ T IU!, i C ~ j '1 1 ,· • r I: ,~ 1 l /, 1 t·i f -.., .. I; ~, t ~ L 'E ~a, ~ r{t ~ f• t •t i I I;ft l -12 ;) :# '' '•' ~ 1 t'' 'f I ' ; t 'I I['· f~~ l', f.. [q: I 1, f. ,· ~ ~ f ,• 1' ' , ¼ I, 'i J'f ' ' I t t ,r ;:i: rt ,, .i 'c I Ii )) '~ I 1= l' f '. ,'fl 4' Ii '" J:1 (!'( 1, "t µ- \ t' r~ tr f 'i l, I ,. . .. . ,, ~ It j i' } ,,} i t ,. ~ '.' #J I ~; t l \ -'ii l t ,. t \. I:-~ ., i T ' .j. i ;; F !if, ~ : ~.! 1·r > j .t ~ ., t p-, f C - k :f lfi ff' ti ,/ T .. . L.l " ll I 't' .. ['j: u, I: I• T t & ' (1 t ,J I/, 11/, i 1, . i t I ,, ' ' ~ f 1, [ c< l • L I i' ll . :. c, i ' 1, w, Ir ' . Ii I , . ~ ' ~ I > . I r : 1/.,: . I L~, : t l'L'. _h 1, ' ... It l tr ,. ,, Ir • I r •J If , 1,::1 ~ ,, It c1 ,! NATIONAL ADVISORV ,. I,' c,! Iv- ' n ' ... . Fi+ ll c • ll I~ C= ilL Ir,- ll'; 1,. .:i b liij of, 11t ll n l ,i:. COMMITTU rot AEIIO ~ -·~~ I 't Ii' lf If 1, .. , ,. I .i K ,,. r l~I s;:ll , 1,, + I, JI ,i .t ' j; ~ C 'tJ ,... 11, r. t Im I,•" f,J: I,'• • 1,. C ', [iJ' I L 11., It, r, ;:_ .,_ l e, l e , If, If I ,~ _, .. c 1,.. 1/J 1,' • lf1: 8 < j I I~: r, lt!: i '": ,, y r, le ~- 11 it l 1, 1 [J ., 1,1: l,1 I 1,-1 I i , .,1,r 11. J < It• '"' ..::>- ., J; ft ' ' I, ;-!. .;:: ., ' ~ l '• ~. •D .J .. f .~ +: L ff I, i Ir ~ ,t i Ir ~ D , . If I n:J 't ltJ F ll-, :.t1 ' . : I : . [ ' ~•. ! : 1, I• ii> • rt it . ' ,; j 1, j Ir :; - J.. I, 1, s" ',, / . iif- - /1 f/, ~n , l/'lr" ' ' r-· ' I :. ~ I .. - I l (a) Dive brakes retracted. Figure M - Effect of fuselage dive-b1·ake deflection on the aerodynamic characteristics in pitch of the 1/5-scale model of the fiepublic XP-1½ d.irplane with original horizontal tail. Idling power, cruising conf~uration. ••••• ••••• ,:·.··. MR No. L6F25 • • • • •••• • ••••• • • •• • • •• ••• • •••• • •• • •• • • ••••••• • (b) Dive brakes deflected so0 • Figure 34. - Continued. ••••• ••••• MR No. L6F25 .••••' . . • • • I :, l e I~ 1 , ~- ·• , _•~ •••• I, ' 1 1 • • ' _, • •••• • , ' l 1[ E _ t , t:. ; :r ~ T , • ,~A i • •• • • •• ••• ,F j '[. I 1 _j • •• I '"' - ,> ;:-.. 1 • I f" I, I - .,.•-; -L~'l .o,Fl,1 ' . 1 2 • • • •J .. Le T r- I l.:) .....:: :-',._ ~ [i / ,-~ I "'i : +I .,. j t & j i: .l:!:; .E • •• -~ I • .,,.1 , •. 'l ~ ~ 1 J if, 'F t1 , - ·;;:; :q) " le ;, •••••• If. I !: ' • • ,. • "+ '~ r.,1 let I..P, 1,t,l l~, lc'i "il= ff; i:tJ: ~-; -- • ,, ,; '" •- '':'" f>f lf' , ,! i i, ;::: f.fJ Ir , , r l",. t, ·I 11 . '+; 11 • ~ ~ .,, -- ffflf If 1r 'H- l~' ''"" "'r ril' ,, •. • 1 t-;- : '1. I, '- I + . r, ~ .• _, l'tt-v. ,U I~! j: ? wr !) f!' lft ff' ,J ti'- "' 11 ! TT'~ : ff I r~ I . : ~ l"r re. t t I, i I ~ ' l ... Ill & i, '[ I, ' t • I f I~ l 1, t 1, ,rti : 1i•; ~ l: .,_._ •,a L..J. ,,,1 - ~ • 1,..1 , , , • Ir ,. '° _, T 1 I t I, IE t lif t tHm ' .'il ' t:°e= · - 1= If ~~'"-4: r-i l~ ll lt:,, t,~ ~Ir!: lE'• -:t- !-, -[ii I [ ...... L< t' 'l T IS ;, "w· t''J. I 1, t I'.+ ... j ,!~ ,, Ir 1, I '- , 1 ·1 , 1 ,~ , • r;,', ., + - ,I 1~ , -- ,•• - . ~ I: I l : 1 lE I, IE" ' '?I, , 11 j l" lt l ,I •' j- /; ::) +: ,F l:I • F~ IF ' .110 ·- l lr. \ 1, 1, . ~w -_,._ 1, ,, a 1/1" L IE i ~. I', I E!- : '1 ., (;:+ t, 1 11 !'t a_· , '"' ~ IF 1 > ' ti. /i rI ff l>I l e NATIONAL ADVISORY 'i !I "r; '' J • r S: , l ,- t ,t f!,1. '/ ''t tJ ,• ' COHHlf!U fOI A!RONAUTICS ; ' ~-- ,) 1_, W/ t 1, "" - ' f .. T l . .. i,.' ., ~ ~ r . ,: " -=- ..._.._ • I ~ . tr ' (c) Diye brakes deflected 90° Figure 34. - Concluded. • •• •• •• •••• • ••• ••• • ••• • • • • • • • • • • • • • • • • •• •• • •• • ••••• • •• ' . . • :z: 0 Figure 35 .- Etteot ot tuelage diTe brakH OD the ••tiated te:raiul llaoh DUllber• ot the RepuDlio lP-84. airplane in nrUoal din•• laUMtH bHed OD wing critical Kach nuaber ot 0,755. GroH weight= 13,324. lb. •• • • • ••: ··· • • •• • MR No. L6F25 • • • •••• ..• • . •••• ' h . . ; • Ir .,, It , :O• • •• • • Ir 1 l ,;; ...... - I: -· ·~ n • •• .=. • • 11 ' t . II, It: • u t ': ·- 1, ,, . L,, •• • •• It· i , • • • r. . • •• I, I ' 1.... - ••••••• "-1 • r. ' •• n • l ,, I [ i: . J ·::Jl f !:rt1 If -t I • ' t ., ' . ; ,, ,,, J ,,. l I• 1, • ' ll. I• IE (! Ift ,. 1. •• " : t i / •.. ; f3 IF I l .l'Y 111/1 . ' I~ " ;_ • , t ·• t , r,. •• , 0 -~ t n I 4- 111 '1 i-- - l e 1-i .... A t , r · ii 1 ~ 'f l:..• "" 0 fH ,. , ' 'I II . .hi 1 F+ ._, ' L .. -- IL ' '• ., ~lj. l E le::; 'I') J I/ Ii ( ,. ' u . · LI 1, n)• l J ~f-1 :, ,_ • It• IE h [;> i i/.( l J ,'{ " l __,__ ,,,.,,,. ---- :--...... _ -l~~+---+++..:+~-;;,1L....f-+--+1------1, ~t-+-++-+-+--1-A'l-t--t-- - -+--+---1-+--+----1 ' ',., ,,.. -- I ·, f NATIONAL ADVISORY ~ ~--1-4---1--+---+---l-+---l- -~--l--l--l-lr-l--+--+--- {a) Power condition A ~dling pow~r { 80 percent ~ ) at sea level; approxi:i,itP. y full p,:;wer (100 percent rim I at J0,000 reetJ Figure 36 .- mssurs distribution over the toJ>'of the rc~elage of the • 1/ <- scale o1el of the Republic 'JJ'- f"J. '1irplru,e •i th the oriv,in,l cane y . • • •• • • ••••• • ,• ... • • • ..... • • MR No. L6F25 ,• • •••• . • •• • • ,__ ,..__ ,__,__ i • • ••• H:.- -1 I• .. • • • •• • f--·-•- •••• • • :, II - • --- u, ••••••• • -/' .... ~ f--· - ,- - ,,. l r ' ~-·Ft I . 1 , ~ /'f\. 1' t . II . . t.l\ "..l - 11 - t K ·Jl T•'t \\ (1 I ' ,\\~ t i ,, I ii\\ .. ['Ill •<- ..... I :i=- ~ - •-,.- - .. ~ I.J, - 1, I., ' • " ~ ~ ~ .I ~ I) I - :r . "'-.;:,~ l I 1:: I"\ ,. . V -~ -r' . .+ ' . ,~ ',(f i -~ u t 'f'. t i 1 ' ,t' I ,. l .,. '-'- _,_ ,-. ~ ' " - I, ' f-- r I .. C I h' 11 ·/ '/ 't Ir ~ I . .. Ii 11 • I I u- ' 0 I() I I r2 9- II s i I• II I/ 1, '7 Id' _, , A '} 1 ? ' t " If :, ,. V d- IA. J :2 •'-' I\. --f-- ,__ h 11 J ''1 1, ll. -,. I t .... I i I• I~ ' [] -- 1--,---1-- ' V " V \ ) L..,.. - ~ r--.... f-- _ _:::I::;, - I i- - - -· ,,.... -- ...... - - ··-·- ~ - i Ir - ·- '--- '-- ,_ ,___ , - NATIONAL ADVISORY '-- --· ' COIO411'TEE FOi AERONAUTICS ,__ I t I I- 1) ~ J~ ~ :.£ -= 1? 1,, .di? 4 ~ f--,- ..J .. I• - ,~ :, ,__ ,.... 1 'rv irn i nn 1:-,= irJ ,_ i I ,.,._f-- n ,.... I I I I I ! l l (b) Power condi t ion B [!u11 power (100 percent r pm) at sea level] Figu~e 36 . - Concluded. • • ••••• . ••• • •• • • • • ••••• • •••••• • MR No. L6F25 • • • • • •• ••• 1--t---1--1-.-+-+!-+-+-1--1- _ ,_ _ _ _,1__.__.__._ 1_ _,__ --t--1--1--1l--1f-.-f---1--1--1---1----1---.._l--1-~ ••• ~ ---- - • • • l,., I • •• -;p Ji I • ,__ - -1---1-~ - :--'- ~-!0--~-l--l _..___,__,___,_-',___,___,_ - __._. _ _.__, --+--t--J-t--i---t---t--t-f---i--+--4---1-1--+ - - - ••••••• • .L '--- '->-- t-- -+--+-+-'++-t---+-l--:-t--+-++-t--t-l-t-+-+-+ + -+-4~1-+-+--+ ---l---l----l--1 ,r .. ]~ - 14.. _, .~"--• I-- 1-- - ~i------_.,._ " j R= I- - r--1- - __ ,_ -- ,- --- I-- - - h------f-- - •-• ,___ ,__ ,_ ,___ ,,,.,. - ,__ _,_ -- L- L- -- 1-- -- •- ·- ·- ,__ ._ ,_ ,__ 1--i 1-- ,_ ,__ ,_ I I ,_ __ ,_ ,__ - ' L- •- --- ~ ,.._ - +--+--~-+-1--41 --1---,l---1--1----+---+-'·- ~1- t-..;--• --+--l- tf-- +--!--• ~ I ,__ ,__ l I I I-- -- -: f - ,__ _,__ I I I _,_ l It;' ~ 4- ,._ ~ '-- - 1-- ' --- ' ' . ,__ (a) Power condition A Udling powtlr (80 percent rpm) at st:a levdl; approximately full power (100 percent rpm) at 301 000 fee] Figur"' 37.- Pressure distribution over the top of the V-front canopy tested on the 1/5-scale c:odcl of the Republic ll.P-1:34 airplane . .. • ••• • • •• • • • • •••• • • MR No. L6F25 •-• ···•• • •• ••• ••• I i [. " I• -- ,,., .tt 1, ' ; • • • 7---t... --l~t-t-+--t----t---t--'--t--+• -t-t--lt-, t-f-i+-+-t--i--lt-t-+-.+-+-++-'-,r-+-+-+-,=+--++--4--!1 •• ••• • •-+- -- • ; + 10 I " 3- It r itr r ,;-,_ 1 • -- __ ,__ ..__ --'-- --r:- r,: I,. . ••••••• • - ~ ~ It j IL· ~- IJ:i: ~ ... :;:: : f I ) fl e 'I. < ~ -, t,,) .. ~ t!t It'!' -f fl;: Ir~, 10:: AT: •t I, • l .:, , --=Ii lih ~hnll • Ir,- lr11 1 r. IJ;.: .._ 1 g + " h. 1, • - :, i N\ailf • 1 !:. l E d: j < ,.. 't i•, Id IJ.:l t-i t; .. ,,_11 , N; r ::. r foJ :E 11: ,, = 1, l "+ ; ., 1, 1,, r :~ R":l7 L , / r-, 11 1, + .!+ ,, ' t 1,;, ~ l :. T r ! J ' ,. t .,. ' l • I / . ' l ,, --- ; I l .. ' l--+---+--+--+" ----l-c.+--+---"r+ "+-+--+-+--r-"f-j -t---l---,-!-l-l-'l----+-+--+----1'-"--l--+--+-+--1--4--l--+---4-'j\-4---4-4-C' -!•--l---+--+---=-l--<~ t• t l il ,. l i j f l ~ I ,, '• l t1 ,. r---. i-: ,. th F• I l l II" 1-, { I+' I t ~ "'"- If l • I . 11- t .. Ii ,l Ir ,, 1, " le · I· ' NATIONAL ADVISORY • COMMITTEE rot AEIIOIIAUTICS . '--- '--- 1 : . .i (b) Power condition B {Jull power (100 percent rp• ) at a a le•!iJ Figure 37.- Concluded. • •••• • • • • •• • •• •• • • • • • • MR No. L6F25 • •••• • • •••• • • ••• • • I ' • ••• ,_ ,~.,..,.,, ~ I • - - - - I// ('/ iii< /: v,.,la ••• i(>,O • • • h1 ff. ~I/', 0 tJ/J - I •••• • • Ir • ft ,::. ,,.. h •••••• IV•, v • • " ~ I L I r : It 11 I ,. I, J/ ' ;l'i rL l -1- ,, ,.,,. .I .,, a I f J, \I .... ~ 0 Tl, / , I). ~/ I ' I, , r} ;, ff ill ' D 8 ,? ? . 'I I ) ) \ I"\ 'v d 01 I V b ~~ 'j 1'A Ir \ \ h1 tfv-- / • !~7 , 'R I ~ \ I I Yl- ,, Ll 1/J IQ rn r ~~ l / .10 !"-1.- 1,· ,1,; :, ( / " I n If I> ill 0 ,. \ / JI> l I> 1 ~ ,::i I? i1 v ---r-:. I ? 1, It ' In , I+ J ,,, ,...- IL rn, h~ I::>. ,, ,,.. It t-Y1 ~ 1 In t.o l.11,. ·.," tnln. , IJI'. ,. ~· I I - (a) Power condition A lidling power (80 percent rpm) at sea level; approximately .full power (100 percent rpm) at 30,000 .feefil Figure 38.- Pressure distribution over the nose o.f the entrance duct of the 1/5-scale ~odel o.f the Republic XP-84 airplane. • •••• • • •• •• • •• •• • • • • • MR No. L6F25 • •••• • t •••• • •• • ' - >- • • • I ,-.. t- • •• -~ - - ~ • • •• l ,I r, ' I ,_ I 1 ••• - ,_ /, re, f{,:i• r ,")C 0 ~ 11 • • • .~ - ••• - n, If!: i11 ~ 'YI ;p I . . I ,.... • I I I • • ,- : ·- ; ,., I I - I ' - I ' ' I , -,{ II. /v ,w II t I I 0 n.11 I. '9 <1 ,v El 1 II ) ''l ,' \ ', .~ 8 ? 12 /Vi I ). . L 14 12 I I :~ "~ "), l:'5 I lL .. _ , ., ..." , \ - \ I : -- L.l. f" I - ' \ I.e.'- I l't... ,_h\ _c..J ~ ,,.. I> \ .u : ·;- ' ,..,, ~ I ' --- - \ _,_ I~ ~ ~ ... r I \ "'\ 1r - l"l;7 I \ "\ 1: - ' ~-->-- i', ' -, 5: ;-, II . ' ' ,- '<.J ,, ' - - 'I~ "; I ,....- l ,,, ll ,; I 1 ['-'->. ' " r T ~- I'-~ f r'-. .... ' ------t ,, r-, ~ I ' V - '- 1 ' ...,~ I I /_ >-I !l - - ,... [;:, ~ ' ~ !:l;f0> ' . . ~ f<::l _.:_ --n :I I [_.l -, L r~ , -""'~ .I ,...- ~I>' ,L (" IL "" (b) Power condition B [full power (100 ?ercent rpm) at sea leviij • Figure 38. - Concluded. IIATIOHAL ADVISORY COINTT£1 RII -.wTICS • •• •• •• •••• ••• • . ••• • •• • • • C • • • • • • • • • • ••• • •••• • •• • ••••• ••• • •• •-· • •• .. j I [ - Ji~ ·-·• ,i :!.1 • .. ~ . ]._ ' '. ±1, ,., " ~, 11 ~ 1 I rt ,. ,, J .. }i l:i i::r l ij n 1 :t. I j .. ~ ,., tl J ; ~ •· ~ ~t 1:.1 . ' fl• + • .. ' . NATIONAL ADVISORY rt COMMITTEl,. ~AUTICS z 0 l ' 1 l 1 Figure 39.- Critical Kach numbers ot two canopies tor the Republic XP-84 airplane, as •timated from pressure-distribution teats ot the 1/5-scale model. Powrer conditions A and B. • ~ • • ••• • •• • ••• • • •• • • • • • • • • •• • • • • • • •••• • • •••• ••• • • •••• • •• • • • •• • Figure 40.- Critical Mach numbers of the outside of the upper nose of the entrance duct of the Republic XP-84 airplane, as estimated from pressure-distribution tests of the 1/5-scale model.