1、RESEARCH MEMORANDUM WIND-TUNNEL INVESTIGATION OF HORIZONTAL TAILS. III - UNSWEPT AND 35O SWEPT-BACK PLAN FORMS OF ASPECT RATIO 6 By Jules B. Dods, Jr. Ames Aeronautical Laboratory Moffett Field, Calif. NATIONAL ADVISORY COMMITTEE FOR AERONAUTICS WASHINGTON December 17, 1948 Provided by IHSNot for Re
2、saleNo reproduction or networking permitted without license from IHS-,-,-NATIONAL ADVISORY COMMITTEX Fcm AER0muT1cs RESEARCH ME- W-L INVESTIGATION OF HORIZONTAL TAlIS. III -UNWEFTABD35 SWEPFBACKPLANFOOF ASEECT RATIO 6 By Jules B. Dads, Jr. The results of a wind,-tunnel investigation of the low-peed
3、aerodynamic characteristics of two semispan horizontal tails having unswept and 35O swept-back plan forms are presented. Each model had an aspect ratio of 6, taper ratio of 0.5, and the NACA 64AOlO section. The data presented supplement previously reported results of tests of models having the same
4、sections, taper ratio, . . and sweepback, but with aspect ratios of 3 and 4.5. Test results are presented for the models with and without standard roughness on their leading edges and with sealed and . unsealed radius-nose elevators. The major effects of sweepback, as measured tithe low-speed tests
5、of the two models having an aspect ratio of 6, were to reduce the rate of change of hingsment coefficient with angle of attack and with elevator deflection, and to reduce the elevator effectiveness. Roughness increased the maximum lift coefficient of the unswept tail, but practically no effect was n
6、oted for the swept-back tail. Removal of the elevator nose seal resulted only in small changes to the lift and hingsment parameters. INTRODUCTION A systematic investigation of the control-surface characteristics, particularly the hinge-moment parameters, of horizontal-tail surfaces has been undertak
7、en by the NACA to provide experimental results for a comparison with those parameters computed by lifting-surface theory. The investigation was to include a study of the effects Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-2 HACA RM No. A7O for th
8、e %nswept“ model and 35O for the swept-back model, as shown in figure 1. The HACA the aerodymmic center was shifted aft about 2 percent of the me811 8erCdynamic chord. The unswept lnodelwas statically unstable near eero lift coefficient fd.+e = 0.00161, uhile the swept+mck model was neutrally stable
9、, 8s shown in figures 4(c) and 9(c). !Fhe experimental results presented in figures 4(c) 8nd 9(c) also confirm the predictions of reference 6 that eat the stall. the static longitudinal stability of the unswept model would increase and that the swept-back model would be unstable. Effect of Standard
10、Roughness The effects of at8nd8x-d leading-edge roughness (elevator sealed) upon the lift and hing-ment coefficients 8re shown in figure 7 for the unswept model and in figure 12 for the swep+back model. Standmd roughness on the unswept model increased the maxi lift coefficient by 0.11 with the eleva
11、tor undeflected, aud by approximately the same amount with the elevstor deflected either down 4 or up 19. The68 incre8SeS were Obt8ined primarily because the stall occurred at a higher angle of 8tt8Ck. The presence of roughness also increased the 8ugle of attack at which the hinge- moment coefficien
12、ts diverged. The value of C of 4.0030 for the unswept model in the smooth condition was c to -0.0036 by the addition of standard -0.0104 to -0.0100. roughness, and Qe w8s ch8nged from Standsrd roughness on the swept-back tail had only small effects on the maximmlift coefficient for any elevator defl
13、ection. The EUIgle of attack at which the hinge-mment coefficients increased rapidly 88 extended slightly by roughness. The value of % (measured inthe linear range) for the sweR-t Jr.1 Wi?xGTmnel Investigation of Borizontal Tails. I -Unswept and 35 SweptGB8ck Plan Forms of Aspect Ratio 3. NACA RM No
14、. A7K24, 1947. 2. Dods, Jules B., Jr.: Wm+unnel Investigation of Horizontal Tails. II -Unswept and 35O Sweptaack Plan Form of Aspect Ratio 4.5. NACA RM No. A Modelwith%tmdmd Mod.el%mooth, elevator roughnes%;elewtor elevataf ee8I sealed eealed removed Unswept -0.0030 -0.0036 -0.0032 -,0104 - l 0100 -
15、.0109 .074 -075 0073 .050 .048 .049 m.68 -.64 -.67 Swept back 4.0028 -0.0028 -0.0027 -.0072 -A067 -Al074 0065 .066 -065 .034 .031 .033 -.52 o-.47 -.51 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-. . . . . Drawl 7 dllnensions in lnc es t.901 H 1.9
16、ol ft. +MS?-q t hlj unbnpr . Figure /.- Plan forms of th hodzontal tall moolds of ospec# rat/o 6. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-. .
17、(a) mee-puarter front view. mgwe e.- !Che unswept tall munted in the 7- by D-foot wind ttmnel. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-_(b) Thre
18、e+uartar rear view. Figure 3.- !Phe 350 nwepW.ack tail. muded In the 7- by N-foot tid tuO.ml. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-c HACA RM
19、No. A8830 19 . .8w d -6 1 ! ! ! ! ! -1 I I lo-PI I -1 I I IA-61 I I I I I Q -13 I I .9 I I I I 9 -/7 I I I I I I I Y/l I I I I /lr I I 1 1 1 A -./. Aspect ratio, 6; R,3.Ox/O? . Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-20 IWCA RM Ho. A8830 . .3
20、6 .32 .28 .24 ./6 N- .08 T .Q c .04 % 2 0 s s F -.04 I B $ -.08 -. 12 -./6 -.20 f / I I I I I I I I I”4 I I -20 -16 -12 -8 -4 0 4 8 I2 16 20 Ang/e of attack, Q, deg fb) Hinge-momenf coefficient. Figure 4.- Con/hued. Provided by IHSNot for ResaleNo reproduction or networking permitted without license
21、 from IHS-,-,-. NACA RM Ro. A8E30 21 . ,28 II 1 ( 1 I .24 ./6 ; -.04 s 2 -.OB 2 -. Q -. /2 -. 16 1 i i i”i i I -.24 -20 -16 EE -/2 -8 -4 0 4 8 12 16 20 0 -4 A -6 V -9 P -/I 4 -/3 V -f5 9 -17 b -20 A -25 Angle of u/tuck, a, deg . /cl Pitching-moment coefficlenf. Figure- 4 - Concluded. , Provided by I
22、HSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-22 ITACA RM Ho. A R, 3.0 x 10.6 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-24 IiACA RI4 No. A8H30 . .6 4 .2 0 I ! ! ! -.6 -.6 I i I i I -.6 :8 -LO P 9 -12 -4 0
23、4 8 I2 I6 20 24 28 32 Angh of oflock, a, tfeg fbl 8, -9:-l5;-20 lps. 6; I?, 3.0x 106 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-26 HACA RM Ho. A8H30 -./2 -./6 -.24 28 I I I I I I I I I I I I I I I I I I I I -4 0 4 8 12 16 20 24 28 32 Angle of ot
24、tock, a, deg (b) Hinge-moment coefficient . Figure Z - Conchded. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-KACA RM No. A R, 3.0x/O? Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-28 RACA RM No. A8E30 x0, 1 ( , , , , , , , , , , , , , , 1 ./6 0 Sealed 0 do ” Air t+l ./2 Q R, 3.0x /Of . Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
