RESEARCH MEMORANDUM - NASA · RESEARCH MEMORANDUM INVESTIGATION AT HIGH SUBSONIC SPEEDS OF THE STATIC LONGITUDINAL AND LATERAL STABIIJTY CHARACTERISTICS "I .. OF TWO CANARD AIRPLANE

RESEARCH MEMORANDUM

INVESTIGATION AT HIGH SUBSONIC SPEEDS OF THE STATIC

LONGITUDINAL AND LATERAL STABIIJTY CHARACTERISTICS

" I ..

OF TWO CANARD AIRPLANE CONFIGURATIONS t

By William C. Sleenian, Jr.

Langley Aeronautical Laboratory 2.' Langley Field, Va.

4.'

is 8"

= . :q NATIONAL ADVISORY COMMITTEE FOR AERONAUTICS

WASHINGTON December 3, 1957

Restriction/Classification Cancelled

https://ntrs.nasa.gov/search.jsp?R=20050019253 2020-03-03T00:08:05+00:00Z

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NACA RFI ~ 5 7 ~ 0 8

I?!~TVESTIC-P?TION AT HIGH SUBSONIC SPEZDS OF THE STATIC

O F TWO CANARD ARPI-JLNE COIWIGiiEwTIONS

By William C. Sleeman, Jr.

The present irwestigation w a s conducted i n the Lmgley high-speed 7- by 10-foot t m e l t o d e t e r d n e the s ta t ic longi tudina l and lateral stebil- i t y cha rac t e r i s t i c s et high subsonhc speeds of two canard airplane configurations previously tested a t supersonic speeds. The %ch nmber range of this icvestigation extended from 0.60 t o 0.94 ea& a I ; l u r i m m angle-of- attack range of -2O t o 2k0 was obtained at the lmest test Mach number. Two wTng plan forms of e q w l area were studied i n the present tes ts ; oce w a s a 60° de l t a k-ing and the other was a trapezoid wing hzving en espect r a t i o of 3, t ape r r a t io of 0.143, and EI-I unswept SO-percect-chord =ne. The cmard control had e trapezoicial plan form and i ts area was approximtely 11.5 percent of the vir?? area. The m o d e l also hed a low-aspect- ra t io highly swept ve r t i ca l t a i l azla twin ventral f ins.

The longitudinal control chmacterist ics of the mdels were consist- ent w i t h past experience a t l o w speed on cmard configurat ions in %hat stallilzg 03 the caznsd surfece occurred at moderate and high control Oeflections for notierate values of angle of attack. This s t a l l i n g could impose appreciable limitations on the nzxirnun trim-lir ' t coefficient a t ta inable . The control effectiveness and maxinun value of t r i m l i f t was significactly increased by zddition of a body f h p having a conical shape and located s l ignt ly behip-d the carlard surface on the bottom of the body.

Addition 03 t h e canard surfece a t 0' deflection had r e l a t ive ly l i t t l e e f fec t on overa l l d i rec t iona l s tab i l i ty of the delta-wing con-pigur&tion; however, deflection of the canard surface from Oo t o loo hed E. lmge favorable effect 02 di rec t ione l s tab i l i ty a t high zngles of a t teck f o r both the trapezoid- m d iielta-wing configurations.

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?resent in te res t in canard airplane configurations arises frm- ;potential perfomance benefits possible a t sGgersonic speeds i n cozrspari- son t o conver;tional tail-reamard an6 tailless airplane designs. The canard arrangeaer,t also offers a solu-kion to p rob lem of balance which are becodng nore aczte wit'n the design trend towzrti =are rearwzrd engine p1acercer.t End accompqying rezrward center-of-gravity Position, partic- ularly for mltiengine arrangerients. Tne nain problez encomtered in the pas t for cenzrl! configzrations was associatee with s t a l l i ng of the canard s.mface vhich severely l i d t e d the alloxable center-of-gravity t r ave l an5 -cke m m i m u n trix l i f t of K?e airplzne . (See ref. 1. ) This problem as well as tne 5ireetional stability d i f f i cd l t i e s fotrnO for some canard configurations icdicated the existence of sorce formidable subsonic problem, and the potent ia l rewards t o be gdned a t subsor;lc speeds by Lsing canard controls did n o t n e r i t s o h t i o n of these problem. The aforementioF-ed supersonic performace ber-efits offer a? effective stimulus to reneved e f fo r t an I"inbi??-g solutions for t i e known lov-speed groblem agd for emloring the general aeroQnmic characteristics of cenzrd airplane configurations a t susersonic speeds.

Arr e-erirr-erital study has been con&xted a t su2ersonic speeds of sone generalized airplane cor-figurations which use canard surfaces for longitudinal control. Soxe of the resu l t s of khis strzdy are presented i n reference 2 and include longitudiml and lateral stabil i ty character- i s t i c s obtained a t Mach numbers of 1.41 and 2.01 for two canard airplane configzat ions &vir-g a 60° delta wing a-6 an aspect-ratio-3 trapezoid wing. Tce coafigurations of reference 2 were selected on the basis of available Fr-formtion as a concept of a gooa supersonic airplane configura t ion heving mhinux changes i n aerodynazdc chwacter i s t ics ikon subsonic to susersonic speeds. It woLzid therefore aypem desirable-in obtaining subsonic infoxation on &n advanced generalized cacard xodel t o use the seme conf igwat ims which were tested a t supersonic sseecs.

We present investigatim was conEucted i n the Langley high-speed 7- by 10-foot tunnel w i t h the mdels of reference 2. Longitudinal and l a t e ra l s t ab i l i t y cha rac t e r i s t i c s vith and without the canard surr'ace aeflecteci were abtained over e Mach number range fron 0.60 t o 0.94 en6 a aax iu -mgle -o f -a t t ack range fron approximtely -2O t o 2k.O a t t h e lowest t e s t Xkci number. In aCdition t o tests of the complete model configurations, assorted 'DreaMown tests were Z S e t o d e t e d n e e f f e c t s of addition of canard surfaces, the vertical tail, ma the ventral f ins . Sone br ie f tests were =de w i t h a bow f l ap &n12 a canard flap i n a t t e q t s to increase the maximam angle of a t tack for which the model could be trimd in p i tch .

NACA RII ~ 5 7 ~ 0 8 3

Lzter.11 s t a b i l i t y r e s u l t s of this imrestigation ere referred t o the bcdy axis system whick i s shown i n figure 1 together w i t h an indic&ion of positive Girections of forces, noxents, and =gular deflections of the Eodel. The l i f t and &rag character is t ics :resented a t zero sideslip are, respectively, norm1 zr?d p a r a l l e l t o the re la t ive wind as shown i n the side viev or" t l e model in f i g m e 1. Moxect coeff ic iects are given about the reference ceDter shown i n figure 2 (located on the body center lice a t body s ta t ion 25). This position corresponds to a location 17.8 percent nem a e r o d y n d c chard ahead E d 7.75 gercent m e a aeroaynunic chord behind the leading edge of the nean z e r o d y n d c chord f o r the trapezoid wing and de l ta wing, respectively.

pitching-moment coefficiect , Pitching moment qSE

Cl rolling-xomext coezficient, Rolling moment

G b

cn yawing-moment coefficient, Y&.-wing m m n t

qSb

cy la teral-force coeff ic ient , Leteral force ss

? air density, slugs/cu f t

S wing area (including aree inside body), sa_ f t

b wing span, ft

4 NACA RI~I ~ 5 7 ~ 0 8

a argle of a t teck of fuselage center line, deg a

F angle cl' sideslip, deg

SC de f l ec t io l mg le of cmarc surface (poEitive wi th t r a i l i n g edge do-m), deg

Subscripts :

9 denotes gartial derivative of a coefficient w i t h respect t o s i d e s l b ; f o r examgle, Cnp = acn

t denotes effect due to addi t ion or' ver t ica l t a i l

M O D 3 D E S C R E T I O N

The basic model configurations tested ere shown in f igure 2 with SOTE of the perticent nodel dimensions. Details of the model geometry are given i n table I and coordinates or' the body are given as table 11.

Two low-asgect-retio-Xing glm f o r m of current interest were tested Y

OE t he s a e boEy t o study t i e character is t ics of two cmard airplane configurations having a highly swept de l ta wing and a trapezoid wing of l o w s-xeep. The 60' Celt& wing haE an Etsgect ratio of 2.31 and g. raxCnun thick- cess of 4 Fercent of the wing chord. The trapezoid wing hac5 an aspect r a t i o of 3, t ape r r s t i o of O.lb.3, and an mswept 80-percent-chord l i ne (28.82O sveepback af .Yge quarter-chord line). The maxirmm thickness of t?"e trapezoid wing was 4 percent of the wing chord also. Both of t i e wings tested were mcie or' s t e e l and had hexagonal a i r fo i l sec t ions with

edge. seniasex argles n o r d t o the leading edge act2 n o m 1 t o t h e trailing

The canara control surface which hzd hexagonal a i r fo i l sec t ions (see f ig . 3) of the same descrl2Cion as for tine wings w a s remotely controlled over a def lect ion rmge frolr Oo t o 15".

TITO a1iri l iary devices (see f ig. 3) were studied as possible meam for obtaining positive pitching-mment irrcrexents t o aid the canard surface is. providing t r i d 9 - g moxerks a t kigh angles or" attack. The body nose f l ap -was a conical segnent 'having a radiirs equal t o the body radius

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a t the f lap leading edge. ?&e canard f l a p was a weOge which sinulated a s p l i t Flag deflected TO0.

The node1 w i t h the trapezoid w i n g w s s modified for part of t'ce investigztion by adding a 5-inch-long cylir_drical extension to the bzse of t h e o r i g i n a l b o u . (See f i g . 2.)

Tests

The present investigation was conducted In the Lmgley high-speed 7- by 10-foot tunnel over e. ,Mach number reage from 0.60 t o 0.94. The everage t e s t Reynolas n-mher based 0x1 the mean zerodyn&c chord w a s agprouimtely k . 5 x 10 f o r t h e delta 'ding and 3 .3 x 10 for the trapezoid xing a t 31 = 0 .go.

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The nodelwcs mounted on a six-cmgonent internal strain-gage balance of the sa.^ descriptioc as t h a t used i n t h e tests of reference 2 end the belence was supported by a variable-angle sting. Longitudinal stability c k r a c t e r i s t i c s were investigated a t zero sideslip thoughost the angle- of-attack range with the Mech number and canard deflection held constant. La tera l s tzb l l i ty der iva t ives of th i s inves t iga t ion were obtained from tests conducted tkrough the angle-of-attack raage with the mo6el a t fixed sideslip angles of *bo. The naxirnm range of anzle of a t tack extended from approximtely -2O t o 2 4 O a t the lovest test Mach number. Some Uni t ed tests were cor-ducted t'nxough a rmge of sideslip aagles from -bo t o l 2 O w i t h the mdel angle of' at-lecb held constant.

Corrections

Jet-bour-dary correc-lions to t he ang le s of a t tack 2nd drag coefzici- eDts de t edced f rou r e fe rence 3 were added t o t'ne data. Blockege corrections zpplied to t'ne Mach r"Ders were Oeternined from reTerence 4. Drag coefficients have been corre.cted f o r a srnall tiznnel-buoyancy effect acii corrections have also been applied t o the drag coefficients suc3 that the base-pressure cocdltions correspond t o free-stream static pressure.

The ar-gles of a t tzck an& s ides l ip of the model have been corrected for defiectiorz OF the balance acd stlng izzder load.

3ACA RM 1.57~08

The effect of the canard on the aerodynaxic charac te r i s t ics in p i tch 5

oI' the delta-xing mdel is presented in f i g a e 4. Effects of cmard deflection on the model wi th the delta a d trzpezoid wings are giver- i n figures 5 azd 6, respectively, and ef fec ts of a b d y nose f lap md canard f l a p a r e s'nom in f i gu re f o r the rrodel w i t h the iielta wing. The e f fec ts of the vent ra l f ins 03 l ong i tud ina l cbac te r i s t i c s fo r t he iielta-wing con2igur&,tion are shorn i n figure 8, an2 ef fec ts of tlrle 5-ir,ch-&fter%ody extension for tbe node1 wit'n the trapezoid wing are show- in f i gu re 9.

Lateral s tabi l i ty der ivat ives of tke model witn the deltz wing which show ef fec ts of the cmard swface, canard deflection, and ve r t i ca l t a i l &re presented. in figures 10 aii 11. Figure 12 ?resents the effects of both the v e r t i c a l t a i l enE the ventral f ins on the l a t e r a l s t e b i l i t y derivazives or' the trapezoi6-uing configpration. AerodynarnLc cimracter- i s t i c s i n s i d e s l i ? showing ef fec ts of the canard sLLrI?ace and canard deflection are presenteC in figsre 13 fo r t'ce &elta-wing cocfiguration.

The v a r i a t i m w i t h Mach nuzber of the longitudinal and direct ional stakili-by a t zero l i f t , of dninun drag coefficient, ar-d of maximan lift- i k a g rzt.io i s gresented in l i gxe 14. LongituZinal chracter is t ics for trin conditions tzroughaut the lift range are given i n figuse 15. Pitcking-monent results are presented in f igure 16 an6 these r e su l t s show ef fec ts of s t a t i c mg2 .3 on t he con t ro l ch rac t e r i s t i c s of the Eodels. Increnental effects or" the canard surface Etnd canard deflection on l a t e ra l s t aa i i i t y p snmete r s fo r t he delta-wing model are presented in f igure 17. Sffects of t'ce verrtral fins on overal l d i rect ional stzbil- i t y and ef fec ts of canard dePlection on the t a i l contribution t o direc- t i o z a l s t a b i l i t y a r e s:?own i n f i g w e 18.

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DISCLESION

I? Cesirable airplzr-e arrengexent would heve the center of gravity located such that tlle fu7-l l i f t i ng cepab i l i t i e s of the wing can be rea l ized in f l igh t with the a i rp lane t r imed et the most forward posit ion of the center of gravity end be no less than neutrally stable with the center of" gravity i n the r e m o s t p o s i t i o n . The cmarci airplane zrrange- nent therefore should typically have a nore forward center-of-gravity position thzn tailless or tail-rearward eirglanes BS r e su l t of the 6estabilizilzg contribution of the canard surface. For exaqle , addi t ion of %he camrd surface to the present delta-wing configuratfon caused a destabi l iz ing s ta t ic nzrgin shift of ap2roximxxtel.y 10 Dercer-t E ( f ig . 4) v through the test Y!ch nmber range. The rather foriard location 03 the reference cezter of gravity for Yle present mdels colnciCed w i t h the

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Eoment center used in the results Tor refereme 2 and does r,ot neces- sarily indicate an optimum center-of-gravity location which would depelld. on both longitudinzl and d i r e c t i o m l stebility and control. T'ne r e su l t s smmarizeb in figure lk show that t'ce low-l i f t s ta t ic =gin was quite large for both wi,ng slan f o r m at a Mach nurdber of 0.60 md increased =bout 3 percent 'c es the bbch number increzsed t o 0.94. The high level of lozgi tudina l s teb i l i ty sham in figure 14 would be excessive for an aircrar't designed t o f l y a t supersonic as well as subsonic speeds and the rroment reference would heve t o be sh i f ted rearw&,rd for appl ics t ion of the present data t o such an arrmgement.

Loagitudinal Stability C"-Ccteristics

Conkrol effectiveness of the basic models.- Effects of canard deflec- t i o n on the longitudinal stability c h r a c t e r i s t i c s of the nodel with the del-La and trapezoid wings are p resen te s i n figures 5 m d 6, respectively, and tria longitudinal chexecteristics obtained from figures 5 and 6 are s w m r i z e d i n figme 13 f o r the lowest and highest test Mach numbers. The r e su l t s of figure 15 show tha t the n a x i m u n lift coefficient for which the n d e l could be t r i m e d with Tie cenzrd surface deflected l5O w z s a l i t t l e greater than 0.30 a% M = 0.60 for both wing p l m f o r u s and decreased to approximte ly 0.20 a t M = 0.94.

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P Reasons f o r t he low values of naximun t r i m lirt coeEicients obtained a re qpa ren t f ron the pitching-moment curves of figures 5 and 6 which show a re la t ive ly high static m g i n and the occurrence of s t a l l i n g of the cmard surfece at the highest deflection angles. In the ebsence of bow and wing induced upwash, the cward angle of a t teck vould be ecykL t o the sirplzne angle of a t tack plus the deflection angle, aGd, therefore, a t high initiel defleckions, stalling of the canard surface would be q e c t e d t o occur at r e l a t ive ly low e i rp lme angles of attack.

In o rde r t o assess the canmd control character is t ics for mre rea- soneble values os" s t a t i c -gin, the h t a of figures 5 and 6 have been referred t o different moment-center locations an6 those results are given i n f i g u r e 16. T??e pitching moments presented i n figare 16 are f o r low- lift s t c t i c Illargios of 5 and 10 percent or' the nean aerodymm5.c chord fo r 6, = Oo. These r e su l t s shov that the r r a x i m t r i m lift vas exbended by reciucing the s t ab i l i t y ; however, there m s very l i t t l e control effectiveness cbove a l i f t coefficient of approximately 0.7 fo r either the delta- wing or the trapezoid-wing Eodel. The problem of the minun airplm-e t r i m lift be iw l imi t ed by s t a l l i n g of the canard was not encountered i n the tests at supe66onic sceeds" ( r e f . 2) because of ' the ber-eficial effects of susersonic Kich number on m?irmm lift, c k z a c t e r i s t i c s . It appears, thererore, that f o r e configuretion having a smll t r a s o n i c aer0Q-c- center shift, the problem of canard c o ~ t r o l e r f e c t i v e n e s s will l i e sri- w i l y i n the subsonic region rather than supersonic.

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A comparison of pitching-moneni; resuLts far t:ne delta-wir!! and trapezoid-whg models >resented in f igures 5 and 6 S~OTV-S some differences which skc'clld be explzined. The values of pitching noxent a t zero l i f t ( f ig s . 5 EEL 6) shm t h a t a larger pitchiag-xornent coefficient ves pro- duced by a given cmtrol i ief lect ion on %he trapezo2.d-ving rcodel tha~~ for the delta-wing model. $,%en interference i s neglecteL, the camrd surface s'r_oul& be expected t o provide the sarce moment regardless of which wing i s 3ehin2 it, and t h i s mment shodd trir- the cozfigJre.tion having t i e lowest sta-Cic =gin t o <he k-igher t r i m - l i e mlue. Tne two wing plan Zorms had the SECT^ area; kowever, the man aerodymdc chcrd for the C e l t z . wing vas Epprosimtely 26 percent greater t:mn tha t for the trap- ezoiC wing, and C3is differezce i s ref lected in the differences ir. canard effectiveness at zero l i f t &n-d in the camrd cor-tribution t o longitudinel s+,abiiity. No% all the differences iz control effectiveness md rraxinun trix lift can be at t r ibuted t o differences in the reference len&n used ir_ the coefficlents; hawever, mxt of the differences shown for the two wing plan foms can be at t r ibuted to t3is source.

Auxiliwy control devices.- Several xeens h v e been s tudied in the gast for increasing the l i f t ing capabi l i t ies of canzrd scrfaces a t low speeEs such as acdition of leadill@;-edge slats acd various ty-pes of trailing-edge flzps. (See r e f . 1.) These devices EZLC recent; clevelop- ments +n E-ie use of bolmd&ry-lz.yer cantrol offer promising means for rzaSeris l ly iacresskg the l i f t ing casa 'oi l i t ies of a canard surface at low speeds. Another a-psroach to the problen of at ta ining t r i m a t nigh L i f t coe4ficier-ts is that of re l ieving the canard surface of the bulk of the xonents t o be trim& by use of' auxiliary trim??zg devices. Some l i r l i t e3 t e s t r e su l t s were o-atained w k t h E body f l a p (shown i n f i g . 3) used ES a device t o provide a posit ive pitchFng-monent increment. Test resl;l-Ls obtained x i t h this f lap for t he delta-wing nodel ( f ig . 7) at e. hhch m&er of 0.60 show khat an appreciable increlzent in pitching- rcornent coefzicient resulted from the addition of the f lap . Eear zero l i f t , -LIIFs increxellt we8 apsroximtely equal to the increznent which would 5 e obtaineC wi th the basic canerd surfsce Oeflected 7". The mi- 111m l i f t coe2ficient st which the model coi;l& be trimmed w i t h a canard slxface deflected 10' w&s increased frm 0.30 t o 0.55 by addLtion of the body flap. A benefit of the bo- f lap, in edc i t ion t o the besic incre- Tent a+, zero lift, wzs the increase in control efzectiveness at high l i f t coefficients. The drag increTer:t of the body f l a p shun i n flgure 7 szggests that it would be suFted only 2s an zis! i n trimming fo r Low- speed f l i gh t .

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I n addikion t o the body fla?, sore r e su l t s were obtained u i t h a YO0 wdge attached t o the czmrd surface as shm- i n figure 3 which simu- la ted a spl i t f1.q derlected 300. Addition of this sinLLa.ted cmard f lap provided mprecia'cle gains i n t r i m l i f t coeff ic ient ( f ig . 7) over the I

besic arrangement; however, t h i s f lzg w a s nuch less e f fec t ive than the . bciy f lap. Of course Ir-uch more effective carard f lap 3sranger:ents a re

d

NACA RM L57J08 9

SossibLe, such as e single or double s lo t ted flap; however, a l l these devices loed tfie canard more heavily rather than provide z t r i m i n g noment tha t would be independent of the canard.

Effect of vez t r a l f i n s and extended afterbody.- Effects of the ven- t r a l f i n s on the longitudillel characterist ics et the lowest and higbest t e s t Yach nurzber are given in f igure 8 w-d show essent ia l ly no e l f e c t of tb-e vent ra l f ins on the longi tudina l s tab i l i ty of the delta-wing model. The lack of asprecisble effects of the vent ra l f ins on either longitudi- na l or d i rec t iona l s t ab i l i t y ( f i g . 18) probably results 2rom the f a c t thzt the center of area of the vent ra l f ins i s loczted. close t o the mment reference.

Tests were -de w i t h an extended afterbody on the trapezoid-wing configdrstion i n order t o es tabl ish the subsonic s tabi l i ty level for st?l evaluation of e f f ec t s of afterbody extensioz on t'ne aerodynamic-center s h i f t i n going from subsonic t o supersonic speeds. The ?resent tests showed essent ia l ly no e f fec t of the afterbody extension 02 longitudinal sta'oility a t low and moderste l i f t coefficients. (See f i g . 9. )

Lzteral Stabi l i ty Character is t ics

Effects of canerd swface snd cznard deflectioc on laterel s t a b i l i t y derivatives.- ETfects of addition of the canard surface and canard deflec- t i o n on t h e s t a t i c h t e ra l stability derivatives of the delta-wing nodel are presented i n figure 10 and ir-crenents obtained from 2i-e l0-sre s-amzrized i n f i g u r e 17 f o r a Mach nm-ber of 0.60. These r e s u l t s show very l i t t l e e f fec t on 6 i r ec t iona l s t ab i l i t y of adding the caa rd su r f ace at Oo deflection at low st?ld moderate angles of aktack. For angles of attack greater t h m 15O et M = 0.60, the d i r ec t iona l s t ab i l i t y was s1ighti.y higher with the canard surface on. Deflection of the cemrd surface t o loo had l i t t l e effect 02 d i rec t iona l s t ab i l i t y izp t o m. angle of a t tack of Bo; however, above this alzgle of ettack, significant increases in d i rec t iona l s tab i l i ty occur red when the deflection was increased from Oo t o loo. (See f ig . 17.) Addi-Lion of the canard SUT- face caused large negative increnerrbs i n t o occur at moderate and

hlgh engles of' Ettack wi th the raxi$m effect occwring a t l5O. The r e su l t s of f igure 17 icdicate furt'iermore that these ef fec ts due t o addi- t i o n of the cm-z;rd surface were associated with interact ion on the wing rather than on the ver t ica l t a i l inesnuch es negative increments i n C

would not be q e c t e d t o eccompany gositive increments of Cyyp vhich came IYom E, ver t i ca l t a i l located above the rol l reference axis .

c z P

2P

The teil-or '? results presented in figures 11 2nd 12 show tmt some of the beneficial effects of deflecting the canard surface a t mderete

10 KACA Rl4 ~ 5 7 ~ 0 8

angles of a t tack can be a t t r i bu ted t o E small reduct ion in the ins tab i l i ty of t'ne wirg-body-cenard configuration. Zven wi th the cenard surface uniie- f lected, a small redxct ion in instabi l i ty with increasing angle of a t tack occurred w i t h the delta-wing configuration, and the trapezoid-wing model I

became directionally stable withoLt t i e t a i l a t high angles 02 a t tack ( f ig . 12). These ta i l -off ckaracter is t ics do zot follov the trends enccuntered on mny swept-wing"bo6y configarations whic3 generally show szbstatial i x r e a s e s i n d i r e c t i o n a l i n s t e b i l i t y a t noderately hi& angles of a t t ack? (For example, see refs. 5 an6 6.) The ta i l -off d i rect ional s tab i l i ty ckarac te r i s t ics of t'ne preser-t models are Sel ieved to be, appre- cFably influenced by two favorable effects not generally present on con- ventiozal mrangeLr.ents. O m of these cmfigurat ion effects i s the absence cf an efter'bo&y behind the wing imsnuch as re fereme 6 shows 2. favor&ble e f fec t of remving t k e afterbody- of a swept-wing-body arrangement. The other favorable effect i s believed t o occur a t the nose of the nodel and is mni les ted by a "strake effect" of %ne canard surface. The strake efTect w a s Tound in reference 7 from s r ~ l l horizontal strakes on a body nose xhic'n a l te red the forebo- flow s-dfficier"bly t o make a highly unstable s7cept-wing-boe arrangezerit becone d i rec t ioml ly s tzb le a t nigh angles. The sua11 favorable effect of cans& def lect ior , for the tail-off configura t ion (figs. 11 ar-6 12, 1.1 = 0.60) cppears t o be furtker manifestation of the s t rake effect as indica%e& by the occ'zrence of posi t ive incremnts ir, both C: and CyB with posit ive increrrmts in control deflection. n3

The largest favorable effect of camrd Zeflectioc was on the t a i l coctr ibut ion to direct ional stability vhich i s s m i r l z e d i n figure 18. T'Aeee resu l t s show that @ins Ettribrtxble t o canard deflection were realized for both wing p k n f o r m and t k a t tie gains were such Kore pro- nounced f o r the Celt&-ving model vkic'n had a greater t a i l contribukion a t hi& angles of a t tack w i t h the canard swface deflected 10' t'nm at zero angle of attack. O n t he ot'ier :?and, -the t a i l coctribution t o dcrec- t i o m l s t a b i l i t y w i t h t'ne trapezoid wing decreased ragidly v i t h mgle of a t tack and becene negative 5-5 high angles. Reasons lor the differences in var ia t ions 03 tail contrLbutions with angle of a t tack For the two wizg plan form have not been establis3ed; however, it i s possible t h a t re la t ive ly minor differences in gemefry, such a s wing root leadiFS-edge location oc the body or exposed root chord length, had an FmportarrL ef fec t on tile flow a t the ve r t i ca l ta i l .

The exper'irnextal directiozai stabil i- ly resul-bs of the present study a t high subsonic speeds me in general agreeaent w i t ' s lox-speed r e su l t s obtained i n the p a s t i n f o r c e t e s t s i n the Langley rfree-flight t m z e l . (For e x w l e , see re3. 8 which presents resul ts la- a canard model having a 60' del ta wing. ) The resGlts of reference 8 Ciemonstrste t'mt &ding a camrd smface deflected 15' has a favorable efiect om the tail-off conTiguration and also increases the ver t ical- ta i l coztr ibut ion to the d i r e c t i m a l s t a b i l i t y a t low an6 moderate angles of attack.

NACA RM ~57508 - 11

Effect of cmerd s u f a c e and camr& deflection on aeroQnmic character is t ics in s idesl ip . - AerodynanLc character is t ics ol" the delta- wing model w i t h aDd without the canard surface are giver? i n figme 13 for angles or" at tack of anproximately Oo ecd and for a Yach nuioer of 0.60. The only s i g n i f i c a t e f f e c t s of the canard surface or canard deflection for an mgle of a t tack of approxiuately 0' was a nose-ap pitchilzg Eoaent md an increese in e f fec t ive diheEral which accompanied e. canzrd del"1ection of loo. At an angle of sttack approxinately 12.3' , an z-ppreciable nonlifiear variatiorz or" rolling-norrent coeflicient wi th sideslip angle occurred when the carlard surface w e s off . Tits f a c t indicated tha t a region of negative effective aihedral existed between mgles of s ides l ip of 51°. Addition of the caaard caused the var ie t ion t o becone l inear up t o bo uld geve the la rge cega t ive incremnt in C

a l so shown In the derivatives of f igure 17. 2P

The var ia t ion 'of L i f t , drag, and ~itching-noment coefficients w i t h sideslip presented i n figure 13 shows l i t t l e change i n lift and drag; however, a t an mgle of a t tack of apnroximlately 12.5O, the configuration w i t h the carard surface deflected loa shared a moderate var ia t ion of pitching-rnoxe-n-t coefr'icicnt w i t h sideslip angle.

The resulks of an investigation et high subsonic speeds of the s tEt ic longi tudiml m d lateral s t ab i l i t y c3a rac t e r i s t i c s of t w o c w r d airplane configurations are summrized in the followirq observations:

1. The longi tudiml control character is t ics indicated tkt s t a l l i n ! of the camrd surface a t ht-gh Oeflection angles (loo t o 1-5O> occ-mred zt re la t ive ly lo7$ model angles of et3ack which could inpose appreciable l imitat ions 011 t he mutinml t r i m lFft coeff ic ient -zttaicable f o r a longi- tudinelly stable configuration.

2. Significant itnpovetxents i n control effectivecess and maximum value 03 t r i m l i f t coefficient were ob-lained Tram d d i t i o n of a body f l ap having a conics1 shape, located slightly behin& the canard on tkke bottom of the body.

3. Addition 02 the canard surface a t Oo iieflection had l i t t l e e f fec t 011 overa l l d i rec t iona l s tab i l i ty of the Cielta-wing model, whereas deflec- t i o n of' the canard surface t o 10' had a k g e favorable effect on direc- t i o n a l s t a b i l i t y a t 3igh angles of a t tack fo r both the trapezoid- and delts-wing configurations tested.

12 NACA RM ~ 3 7 ~ 0 8

4. T'nere xere mrked d i f fe rences in overe l l d i rec t iona l s t sb i l i ty of %he delta-wing and trzpezoid-wing models w i t h the canard surface deflected LOo. DFrect ioml s tabi l l ty of t5e delte-wing model was greater a t high angles c~f a t tack thas &t t i e Lowest apsles, whereas the complete - model w i t k t 3 e t r q e z o i j . wing becme directiozally unstable at e xoder- e te ly 3igh mgle in spite 0: $he a2arernentioRed bell-efits of canard CeTlection.

Lmgley Aeromutical Ldcoratory, Netlor?al A6visox-y Comittee for BeronaxLFcs,

sangley Field, Va., September 17, 1957.

NACA E4 L57J08

REFEZENCES

1. Jobnson, Joseph L., Jr.: A Study of the Use or" Various Hi&-h--Lift Devices 02 the Horizontal T a i l of a Cmsrd Airplane Model ss E Kerns of I x r e e s i n g t'ne Allowable Center-of-Gravity Travel. N4CA RM ~521a83, 1953.

2. Driver, Corcelius: Longitudinal smi Leteral S tab i l i t y end Corr-Lrol Chsrscter is t ics of Two C m r d Airplane Configurations a t Yich Nwbers of 1.41 end 2.01 . K4CA RV ~ 5 6 ~ 1 9 , 1957.

3. Gillis, Clsrence L . , Polhasus, Edward C . , and G r z y , Joseph L . , Jr . : C h a r t s f o r Determining Jet-Boundary Correctiocs for Conplete Models i n 7- by 10-Foot Closed. Rectangular Wind Tunnels. NACA lWB L-123, 1945. (Fornerly NACA ARR Ls31.)

4. Herriot, JoBn G. : Slockge Corrections for T1.lree-DFnensional-Flo~J Closed-Throat Wind T-mels, With Consideration of Vie Effect of Compressibili-ty. NACA Rep. 995, 1950. (Supersedes NACA RM ~ 7 ~ 2 8 . )

5 . Fev, Albert G., Jr.: Investigation 2% High Subsonic Speeds of the S t s t i c La te ra l and Direct ional Stebi l i ty and Tail-loeds Character- i s t i c s of s. Model Baviog e. Eighly Tapered Swept Wing of Aspect Retio 3 .snd Two Horizoatsl-Tail Positions. NACA RM L56E29, 1936.

6. Polhmus, Edwara C., and S g r e e m , Kenneth P.: Subsonic Wind-Tunnel Investigakion of the Effect of Fxe lage Af'te-rbody on Directional S t ab i l i t y of: Wing-Fuselage Combinetion6 a t High h g l e s of 4"t;taclc. NACA TN 3896, 1956.

7. Sleemr?, Willian C., Jr.: Investigctioa a t Bigh Subsonic Speeds or" the Effects of Various Borizontsl Fuselage Forebody Fins on the Direct ioml md Longi tudinal Stabi l i ty of a Cozglete Mofiel %vil.lg a 45' Sweptback Wir!!. K4CA RM L5&-25, 1957. Y

8. Bates, Willim R.: Low-Speed Static Lateral Stabil i ty CharacterLstics of a Csnard Model Eaving e 60' Triangular Wing and Iiorizoctal T a i l . XACA E4 LgJI2, 1949.

14

3ody : Xaximuc? Biazeter. i n . . . . . . . . . . . . . . . . . . . . . 3-50 Len&.h. i n . . . . . . . . . . . . . . . . . . . . . . . . . . 37.00 Bese area. sq in . . . . . . . . . . . . . . . . . . . . . . . 9.582 Tineness r e t i o . . . . . . . . . . . . . . . . . . . . . . . 19.57

Trapezoid wing: Bgalz. i n . . . . . . . . . . . . . . . . . . . . . . . . . . . 25.72 Chord at bw-Xing ic tersect ion. in . . . . . . . . . . . . . 13.25 Area. sq f5 . . . . . . . . . . . . . . . . . . . . . . . . . 1-53 Aspect racio . . . . . . . . . . . . . . . . . . . . . . . . 3 Tagerracio . . . . . . . . . . . . . . . . . . . . . . . . . 0.143 Yhic:kness r & t i c . . . . . . . . . . . . . . . . . . . . . . . 0. 04 hfezc geometric c k o r ~ . in . . . . . . . . . . . . . . . . . . . L0.184 Sweeg argLe of le.=&tzg ebge. deg . . . . . . . . . . . . . . 38.67 &-ee> &@e or" trailiY4 edge. deg . . . . . . . . . . . . . . -11.3 Leading-e&ge half-mgle. mrml t o L .E.. keg . . . . . . . . 5

5 n Lrailing-edge hlf-mg1e. n o r r l t o T.E., de@; . . . . . . . . . Delce -%ing:

Spar. i n . . . . . . . . . . . . . . . . . . . . . . . . . . . 22.56 Chord az bow-ving in5ersection. 2- . . . . . . . . . . . . . 16.51 Keen geometrlc c?-ord. in . . . . . . . . . . . . . . . . . . . 13 . 027 Area. sq f t . . . . . . . . . . . . . . . . . . . . . . . . . 1-53 Aspect rc t io . . . . . . . . . . . . . . . . . . . . . . . . . 2 3 1 Thickness ratio . . . . . . . . . . . . . . . . . . . . . . . 0.036 Ledirg-edge klf-engle. n o ~ r . 1 t o L.Z., deg . . . . . . . . 5 Trailing-edge half-angle. n o r m l t o T.E., deg . . . . . . . . 5

CEnarc? : Cree ( t o t a l t o body cenzer 1Lr.e). sa_ in . . . . . . . . . . . 25.35& Ares. eaosed (eack cazwa). sq i n . . . . . . . . . . . . . . 6.7b2 Spm. emcse3. in . . . . . . . . . . . . . . . . . . . . . . 2. 25 Mean geozetric c.1ord. i n . . . . . . . . . . . . . . . . . . . 3-33 Za%ic of t o t a l ctirard ares t o t c t a l wiog exea . . . . . . . . 0.115

?krtical tai l : Area. expose&. sq PC . . . . . . . . . . . . . . . . . . . . 0.279 S g m . exposed. i n . . . . . . . . . . . . . . . . . . . . . . 4.25 Aspect ratio . . . . . . . . . . . . . . . . . . . . . . . . 0.439 Sveep of lee3ing edge. <e@; . . . . . . . . . . . . . . . . . 70 Sectioll . . . . . . . . . . . . . . . . . . . . . . . . 3/1.6-i~. slab LeeCing-edge i-&lI".mgle. zormsl t o L.E., aeg . . . . . . . . 5

Ven'crel f ins: k e a . each fi?.. eqosed. sq f+, . . . . . . . . . . . . . . . 0.13 Spa?. emosed. i n . . . . . . . . . . . . . . . . . . . . . . 2.25 Aspect r e t i o . . . . . . . . . . . . . . . . . . . . . . . . 0.271 Sweep of leaCing edge. deg . . . . . . . . . . . . . . . . . 63 Sveep of t r e i l i n g edge. deg . . . . . . . . . . . . . . . . . -77.5 LeeCing-edge helr".acgle. n o r r z l t o L.E., CeE; . . . . . . . . 5 Trailing-eQe ?xilf.zngle. ?loma1 t o I .3.. deg . . . . . . . . 5

.

Body s ta t ion

0 * 297 .627 - 956

1.285 1.615 1 943

2.605 2 936 3 267 3 598 3 - 929 4.260 4 592

2 -275

4 = 923 5 0255 5 -581 5 920 6.252 6 - 583 18.648 37 -000

RaCius

.a24 865 -903 .940 .958 996

1.020

1-07? sectioz 1.75

0 .076 .156 -233 307

$378

509 573 .627 .682

k h 4 5

-732 .780

16

Y Lateral force \

NACA RM L57J08

L I f l

A i pJ Yowmg moment

i

i Z

Figure 1.- Body reference axes showing posit ive directions of forces, moments, snd angular deflections.

A NACA RM ~57508

Figure 2.- General a,rr.zngenent of the basic model configuration showing the delta-wing and trapezoid-wing plan forns tes ted. (All d b n - sions are in inches.)

t-2/45 A

260 =&dto spreoder rod

Body flap Center mwnthg bracket

Figure 3. - Details of the body nose flap and simulated canard sp l i t flap tested on with the delta wing.

F P

ul I? 4

the model 2 03

I

25

20

J5

10

-a

c1

8: - 5 4

0

25

%O

15

IO

5

0

-5

.30

.25

-20

.I5

.IO

b b

6 0

0

.30

-25

.20

.I 5

.I 0

.05

0

-4 72 0 .2 4 .6 .8 ID L2 L i f f coefficient ,C' Li f t coef f ic ient ,G

Figure 4,- Effect of the canard surface on the longitudinal characteristics of the delta-wing configura.tion.

.I 0

.05

0

N 0

+s s E a E I

c CI

-..I" -4 -2 0 2 4 .6 .8 IO I2

h z a

0

0

0

-05

"IO

45

-113

-25

4' -5 0 5 IO I5 20 25 30

Li f t coef f ic ient ,C, Angle of attack , Q , deg

Figure IC. - Concluded.

I 9

Y '

"

r I

-30

I

25

20

I5

I O

b 2 . 5

b ,

x 0 * 2 0 P

0

-4 72 0 .2 4 .6 .8 I ! ! 12 -4 -.2 0 .2 4 .6 .8 I ! ! 12 L i f t meffIclent,CL LiFt coefflcient,CL

Figure 5.- Effcct of canard deflection on the longitudinal characteristics of the delta-wing configuration.

25

-20

.I5

. 10

.I! 5

0 .IO

.05

0

I :LJ -4 -2 0 2 4 .6 .8 ID I2

L i f t wef f ic ienf ,CL

10

05

0

:05

-IO

45

120

-25 -5 0 5 IO 15 20 25 30

Angle of offack, 0 , deg

Figure 5. - Continued.

.J 5

.I 0

-05

0

I IO

.05

0

YO5

-.IO

7 2 0 -4 72 O .2 4 ,6 .8 JD L i f t coefficient,CL

.J 5

.I 0

-05

0

I

Figure 5. - Concluded..

e; d 03

-5 0 5 JO 15 20 Angle of attack, Q , deg

w N

25

20

I5

lo 'b 8: PI - 5

0

0

30

25

.20

I5

.IO

05

0 3 9

0 .20

.I 5

0 .IG

.05

0

-4 -2 0 .2 4 .6 .8 I ! ! L 2 L i f t coefficient,CL

-9 12 0 .2 4 .6 .8 I! L 2 Lift weff icient,CL

Figure 6.- Effect of canard deflection on the longitudinal characteristics of the trapezoid-wing 03 configuration.

\

I c I I *

Figure 6. - Continued.

:*y4 :2 0 2 4 .6 .8 ID 12 L i f l coeffment ,CL

-5 0 5 10 15 20 25 30 Angle of attack, (I, deg

." -4 72 0 .2 4 .6 .8 ID -5 0 5 10 I5 20

L i f t mefficient,CL Angle of attack, u , deg

. I .

L

-0 P b

.rC

r, r,

B a x a Y h 4 T

25

20

15

IO

5

0

0

0

30

25

-20

.I5

.IO

05

0

0

0

30

25

.m

.I 5

.I 0

0

-4 -2 0 2 4 .6 -8 I.. L? L I f f coefficlent,CL

tc VI 4

0 4 [x,

F ' @ m e 7.- Effect of body nose flap and canard del-ta-wing conf igurE

flap on the longitudinal characteristics of ltion. M = 0.60.

.I5

io

D5

0

IO

05

0

.05

"IO

-15

-113

'2% -.2 0 2 4 .6 .8 ID I2 L I f f coefficienf ,C,

.I 5

.I 0

.05

0

I O

05

0

705

-.IO

-f 5

432

-.a -5 0 5 IO 15 20 25 30 Angle of affack, 0 , deg ul I?

4

8 Figure 7.- Concluded. (Flagged syllibols indicate 6, = 1.0'. ) a3

b 4

I I

25

%O

15

lo b

c

P - 5

4 I I 1

F

-4' -.2 0 2 4 .6 .8 fD I2 L i f t mefficient,C'

-4 72 0 .2 4 .6 .8 10 l2 L i f t coefficienl,CL

Pigurc 8.- Effect of the ventral fins on the longitudinal characteristics of the delta-wing configuration.

I O

05

0

0

0

0

-05

-.IO

-I5

- 2 3 , -5 0 5 IO /5 20 25 30 Angle of attack, u , deg

I I

”

I b

I 1

"_ 1 b

25

20

15

IO

b

b

P . 5

0

0

0

30

25

20

.I5

.IO

8 F -.- 05

0 .30 c,

9, D c,

.25

9 ?

0 .a

.I 5

0 .IO

-05

0

-4 72 0 2 4 .6 .8 ID 12 L i f f coefficient ,CL

Figure 9.- Effect of >-inch extension of the fuselage af'terbody on the longitudinal characteristics of the trapezoid-wing configurakion. 6, = Oo.

I

w P

”

-dw -4 72 0 .2 4 -6 .8 IO 12 L i f t mefflcienf ,C,

0

0

-5 0 5 IO 15 20 25 .?Q Angle of attack, a, deg

Figure 9.- Concluded.

I I

I 1

I

01

1 1

01

0 c%

- 01

Q02

001

crib

-001

001

0

-001

-002

-.Om

“004

0 CY b

-Dl

-02

002

,001

crib 0

- OOf

m1

0

-003

-004

-5 0 5 10 15 20 25 30 Angle of ottock,u, deg

-5 0 5 10 I5 20 At?g/e of attack, u , deg

.- .”

I * ;

P E

Figure 10.- Effect of the canard surface and canard de:rlection on the lateral s tab i l i ty derivaAives of the del-ta-wing conSiguration.

34

or

mr

0

0

403

NACA Ri ~57~08

-5 0 5 10 15 20 -5 0 5 10 15 20 Angle of ottuck, a, deg Ang/e of ottock, (I, deg

Figure 10.- Concluded.

1 I I

-5 0 5 IO I5 20 25 30 Angle of attack, 0,deg

-5 0 5 IO 15 20 Angle of affack, a , deg

Figure 11.- Effect of the verbical ta i l on the lateral stability dcrlvatives of the delta-wing configuration with the ventral fins removed.

01

0

-01

-02

002

.00 /

0

-001

.001

0

~ 0 0 1

cia ,002

-.004

01

0

- O/ - 02

002

DO/ .. '9 a

- oo/

.oo/

0

-.oo/

-.m3

-004

0

-O/

-02

.002

%! 0

-DO/

.oo/

0

-. 001

-m

-003

-.m4

NACA RM L57J08

-5 0 5 lo 15 20 Angle of ottock, f , deg

-5 0 5 lo 15 20 Angle of ottock, Q , deg

Figure 11. - Concluded.

Dl

0

701

002

.001

-002

.m3

.m2

001

0

002

I b

-5 0 5 IO I5 20 25 3 ~~

-5 0 5 10 15 20 Angle O f Uf fUCk, u,dq Angle of oftuck, a , deg

Figure 12.- Etfcct of both the vertical tail and ventrd. f i n s on the lateral stability derivatives of the trapezoid-wing configuration.

NACA RM L57J08

Angle o f aftuck, a, deg Ang/e of attack a deg


C n

Figure 13. - EPfcct of the canard surface and canard deflection on the aerodynamic characteristics in sideslip of the delta-wlng configuration. M = 0.60.

- 4 -2 0 2 4 6 8 IO I2 I4 -4 -2 0 2 4 6 8 IO 12 I4

Angle of stdesllp, /, deg Angle of sldesltp,/, deg

(a) a = 0’.

I I

-4 -2 0 2 4 6 8 io 12 14

Angle of sideslip, a, deg

-4 -2 0 2 4 6 8 f0 12 f4

Angle of sideslip, ,8, deg

(b) a = 12.2'.


I , L

6A NACA RM ~ 5 7 ~ 0 8

8

6

.002

0

.04

.02

0

41

Figure 1k.- Variation of stat ic longi tudinal and d i r ec t iona l s t ab i l i t y parmeters, lnfninuzli drag coefficient, and ~lraxFnu?l? lir”t-dreg r a t i o w i t h Mach nmber.

42

20

'p lo

0

- R L

06

-04

02

0

M = 0.60 M =0.94

10

5

0

NACA RE: L57JO8

-. / 0 .l 2 .3 0 .I .2 3 r i m / f f t coefficient, C,

Figure 15.- Variation of longitudinal characteristics for trim condi- t ions of the complete rr;odels h v f n g the delta wing and the trapezoid wing.

.

.IO E static morgin for & = 0"

l.

91 4

0 0

8 ; A 15 OBE stotic morgin fw &=OO

.. Y

12 0 .2 4 B 4 10 12 -2 0 .2 4 .6 .8 10 I.2 L i f t coefficient, C, L I f f coeffklent, C,

Figure 16.- Pitching-moment characteristics of the models showing control effectiveness of the canard with two values of low-lift static margin. M = 0.60.

!a

P i5

I w c

44

A

0

-.oo/

0

NACA RM L57J08

lncremenf due to conord "- Increment due to /Oocanord

deflectton

-004

Angle of otfock, a, deg

Figure 17.- Increments i n l a t e r a l stability derivatives due t o the canard surface and canard deflectior, for delta-wing configuration.

L

A

n

.

D

.Om

002

031

0

7001

.003

002

.oo/

0

.

.oo/

0

,001

Angle o f affock,a, d !

Figure 18.- ETfect of canard deflection on the %ail contribution to direct ional stzbil i ty for the delta-ving and trapezoid-wing models and ef fec t ol" the ven t r a l f i n on the d i rec t ionz l s tab i l i ty Tor the delta-wing configuration. M = 0.60.

Documents

RESEARCH MEMORANDUM - NASA · RESEARCH MEMORANDUM INVESTIGATION AT HIGH SUBSONIC SPEEDS OF THE STATIC LONGITUDINAL AND LATERAL STABIIJTY CHARACTERISTICS "I .. OF TWO CANARD AIRPLANE