1、RESEARCH MEMORANDUM TRANSONIC WIND-TUNNE L MEASUREMENTS OF STATIC LATE-R.A$ A-LTIECTIONAL STABILITY AND VERTICAL-TAIL LOADS F A MODEL WITH A 45O SWEPTBACK WING 4 By Joseph M. Hallissy, Jr. E z, Langley Aeronautical ?Laboratory . r I Langley Field, Va. ? PATIONAL +a ADVISORY COMMITTEE i I a I3 0 LLI
2、x FOR AERONAUTICS WASHINGTON May 17, 1956 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NACA RM L55TLL9 NATIOIQSL ADV Ey Joseph M. HallFssy, Jr. h investigation to deternine the vertical-tail loads ad airplsne characteristics in sideslip for a =ode
3、1 of a swept-wino fighter-tyye airplane WES conducted in the kzley 16-foot trmsonic tunnel 2% tio of 3.56, a taper ratio of 0.30, end utilized NACA 6k007 airfoil sections. The directional stability at a Mach nmber of 0.80 was approximately constat tr?_rough the test angle-of-=%tack ra-se. At higher
4、speeds, although kving a greater initis1 value tnan at a Mach number of 0.80, the directional stabili$y decreased with angle of attack, es did the vertical-teil loads. At subsozic sgeeds the directional stzbility for zero =?le of attack was found to be sonewhat less t very small angles of sideslis t
5、hm ai; =oderake angles. The load on the exposed vertical tail regresected between 60 and 80 percent of %he total tail contribiztion to side force, and the maxibum trzvel of the center of Sressure with angle of at%eck and Yach cumber was about 7 percerxk of -the height ugwmd end 14 percent of the cho
6、rd rearward. c Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-2 I NACA RM L55Ll.9 Therefore, wher?. a sGpersoniT-fis, including the tail-load coefficients, are referred to this center-of-gravity locatior- through the stability axes system. wing sgm-
7、 vertical-tail height from defined root chord, figure 2 wing xem aerodynamic chord local vertical-tail chcrd rolli-%-rconent Coefficient, Rol1i-w xonent SSb rclling-noment coefficient Cue to load on the exposed vertical tail, Tail rollirx nmxent qSb pitching-moaent coefficieat, Pitching mment ss E y
8、awing-mnert coefficient dLe to load on the exposed vertical Tall yewing nonerh qs-D side-force coefficien+, Side force ss Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NACA L55Ll-9 - 3 side-force coefficient due to load on the exposed verticsl tail
9、, Tail side force SS M free-strean Mach number a_ Tree-stream dpmj” p- ressure S tokal wing area a angle of atteck masured *on? the wFrg chord plme, deg P angle of siTS APlD DISCUSSION NACA RM L55IJ.9 Effebt of the Umealed Vertical-Tail Root 00 Airplarre Coezficients It was believed at the +,iEe of
10、the %ests tnat the small gap around the base of the verticd. teil cauld be left unseeled withaut adverse effects, and therefore, as indicated in the t2ble of tests, most of tce tests were rmce with no seal. Tne results, however, as shown in fig- -zes 5 and 6, incicate effects of appreciable mzgnitud
11、e. Figure 5 shows that at CL = Oo tne lack cf a seal resulted ir decreased (absolute) velues of all three lateral coefficients, and thus in the thrae sideslip derivatives. This was especially true for slrall axgles of sideslLp, the curves for tiie instmxented (unsealed) tafl behg eppreciably more fl
12、at- tened as they pass tbzough p = 0. The .laterel derivatives as detedned from the em5 points only (+?O c-d -50) are ?ovn in figure 6 for the two tail installations. The lcsaker- at 3O sideslip angle have been included in fi,gures 11 cd 12 with the total vertical-tail cozrtribu- tions to lateral md
13、 directfond stability. The latter, or“ coilrset include not 0- t?e lozds 02 the vertical tail but also the loads induced Sy the vertfcal tail on the fuselage znd otker pe3“;s of tke aiq1m-e. As witn the total tail con?zibutions MYp and 4lp, both CyA “B and Cnt decrease with angle of attack, especial
14、ly at the higher sseeds (fig. 11). Both nents that is, breaks in the curre caused by abrupt stalli-ng of one wing aze reduced. - the sepaation is better controlled and more graical-tail-fasele junctwe was ?lot sealed for nost of Yhe tests (tinzs in3roducin.g sone a_;a-titztive errors), the following
15、 conclusions are indicatetee for Aerosau-Lics, Tbngley Field, Va. , Nwmber 30, 1955. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-1. Zbnmu, Charles H. : Recent Stzbility end Aerodynmic Problem and Their Znplicztions as to Load Estimtion. NACA RM L
16、55Ella, 1955. 2. Krhn, Richad E., Halllssy, Joseph M., Zr., and Stone, Ralsh W., Jr. : A Disc:ussion of Recent Wind-Tms-el Sixdies 3elating to the Problem of Estim%ipg Vertical- and Horizontal-Tail Loads. IWCA IIM LELE, 1955 3. Rackel, Jack F., and Schmeer, Jazzes W. : The Aerodynamic Characteristic
17、s at Trmsooic Sseeds of a Xadel Xith a k5O Swestback Wing, Lrrcluding the Effec-L 05 Leading-Edge Slats and a Low Horizontal Tail. UCA RX L53J08, 1954. 4. Whitcon-Fuselage Combination and the Fuselage Alone Obtained ir- the Langley 8-oot Wan-sonic Tmel. MCA m L52X14, 1952. 7. Toi.hem.us, Ed-md C., e
18、nd Sleemzn, FJfllian C., Jr.: The Rolling-en-t. Figure 5. - Concluded. - Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-20 P Plain vertical tail (sealed) - - - - - Ins truxented vertical tail (unsealed) 0 - .4 -1.2 .80 .90 .95 1.00 1.05 Mach Number
19、Figure 6.- Zfect of urleealed verticzl-tail root on the airglace sideslip derivatives. a = oO. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-“ . I , , I u M 1.03 1.00 . 0 C P) - t *E .95 Y- *k- .- 0 P) 0 0) 0 P) 2 .90 c P cn BO -4 -2 0 2 4 6 8 IO 1
20、2 14 16 Sideslip anqle, ,6,deq (a) Side force. Figure 7.- Vertical-tail-off variation of lateral airplane coefficients with sideslip angle at u = 0. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Provided by IHSNot for ResaleNo reproduction or netwo
21、rking permitted without license from IHS-,-,-I I I . c c 0 .- WM E 103 W 0 0 .90 Sideslip nngle , p , deg (c ) Rolling moment. Figure 7. - Concluded. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-2L: Sideslip angle, p , deg (a) Vertical-tail latere
22、l force. Figure 8.- Variation of lateral forces md noclents with sideslip at on tke instrumented verticd tail (unsealed). a=O 0 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Sideslip ongle , p , deg (b) Vertical-tail yawing moment. Figure 8.- Cozti
23、nued. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-26 Sideslip angle , p , deg Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-FA 0.80 .90 .95 I .oo 1.03 Vertlccl rail on 0.80 M .90 .95 I .oo I .03
24、 M 0 80 .SO -95 =$3 I .oo I .03 M 0 80 .90 .95 I .oo I .03 %13 M 0.80 .90 .95 I .oo 1.03 .I M 0 0.80 0 .90 0 95 0 Czp 1.00 0 I D3 -.I 72 04 8 12 16 Ange of otrack, Vertical :ail ofi Q, deg Figure 9.- Veziation of sideslip derivatives with angle of attack. Unsealed verticel tail on and off. - i Provi
25、ded by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Vertlccl tal on 0 0 -2 -. 4 -6 -8 -8 I Ill Q 0 A 8 II 13 15 Cy0 a 0 4 8 II 13 15 U 0 4 8 II 13 15 number, Vertical tail off 0 0 0 0 0 0 -.2 -.4 -.6 -. 6 0 0 0 0 0 0 -. I -.e Figure 10.- Varietion of sideslip
26、 derivatives with Mach number. Unsealed vertical tail on and off. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-a I d r M RO 90 “- Toto1 varllcol toil contrlbutlon (vertlcol toll on-verflcol 1011 off), AGy ACnp or ACl “_ Meosured fa11 load, CnlP ,
27、or GI P B a 0 - “- “ “ “ - “. _ _.- - 1 “-7“. -. - - -.6 4 “ “ - .2 -. “ - -“-.“-. _“._“ .- “ “_ - - “- - .O c Angle of ottock, a, deg Figure 11.- Variation with angle of attack of unsealcd-vertical-.l;ain. contribution to the sideslip derivatives. E h D nl Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-