NASA NACA-RM-L51I06-1951 Effects of horizontal-tail position area and aspect ratio on low-speed static longitudinal stability and control characteristics of a 60 degrees triangularable.pdf

1、I EFFECTS OF HORIZONTAL-TAIL POSTl?ION, AREA, I AND ASPECT RATIO ON LOW-SPEED STATIC LIONGITUDINAL STABIm, TICS OF A 60 TRIANGULAR-WING MODEL HAVING VARIOUS TRIANGULAR-ALL- MOVABLE HORJZONTAL TAILS By Byron M. Jaquet Langley Aeronautical Laboratory Laqley Field, Va. “ - “ . . WASHINGTON December 14,

2、 195 c . ., Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-.- REXZARm MEMORANDUM EFFECTS OF HORIZONTAL-TAIL POSITION, AEEA, AMD ASPECT RATIO, OW LOW-SPEED STATIC LONGITUDINAL STAB= I AMD COJYTROL CHARACTERISTICS OF A 60 TRIANGUIAR-WING MODEL HAmG VA

3、RIOUS TRIANWUR-ALIr “! MOVABLE EORIZOWTAL TAIIS By Byron M. Jaquet A low-speed investigation was made in the Langley st however, adequate longitudinal control is difficult to obtain for these airplanes with manually operated. controls. For example, constant-chord flap controls have good effectivenes

4、s at low speeds, but inherently have undesirably high hinge moments (references 1 and 2), and half-delta tip controls, which permit a wide choice of hinge- location for aero- aynamic balance, have low control effectiveness at low speeds (refer- ence 3). In another case, a canard was found to be virt

5、ually ineffective as a fixed trimming device at hfgh lift coefficients in a low-speed Y investigation of a canard tri-ar-wing arrangement (reference 4). III Great Britain1 by Lock, Paee, and Meikler, some promise has been indicated for all-movable .tails located behind the center of gravity although

6、 some instability was encountered near the stall. An all-movable tail, in addition to providing longitudfnal control, should overcome some of the other difficulties encountered wtth semitailless airplanes. The hori- zontal tail would provide additional damping in pitch, which is low for -triangular

7、wings. (reference 5), and perhaps eliminate the possibility of tumbling (a continuous pitching .rotation about the lateral axis) which is also associated with semitailless airplanes. . In addition, the center- of-gravity travel would not be as severely restricted for an airplane with horizontal tail

8、. l and not as a stabilizer. In the present .inyestigation (which is a part of a research grogram being conducted 3.n the Langley stability tunnel to 1- I .r lNot-generally available. * Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MACA 51106 3 det

9、ermine the suitabilitj. of various types of controls for trlangul v P 2 z a NACA RM 131106 root- chord, feet spanwise distance measured from and perpendicular to plane of symmetry, feet free-stream dynamic pressure, pounds per square-foot F) dynamic pressure at tail, pounds per. squ,are foot free-st

10、ream velocity, feet per second density of air, slugs per cubic foot tail length, feet- (distance between quarter-chord poitio of 2.31, R = 60, and modified NACA 65(,6)-006.5 airfoil sections parallel to the plane of symmetry. The Fuselage had a circular cross section and a fineness ratio of 7.38. Ad

11、ditional detaiis of the fuselage may be obtained from reference 6. Three of the hori- zontal tails had.the plan form and thickness ratio as the wing but had areas of 5, 10, and 15 percent of the wing area. An additional tail of aspect ratio 1.07, ,Arn, = 750, and an area of 5 percent of the wing. ar

12、ea was used for a few tests. The tails. -were supported by r- by 2-inch , Steel support atrube (one BtrrZt was used for each tail height) iounted on a 2.- by - 1 by 45-inch steel bar, the lower. surface of which was . parallel to but 1.5 inches above the fuselage center line. Pertinent model details

13、 .and tail locations are shown in figure 2 and details of the horizontal tails are - shown in figure 3. Tails I, 3, an however, the wing-fuselage maximum lift coefficikt is about 10 percent lower than that obtained previously. The lift and pitching-moment characteristics of the wing-fuselage and hor

14、izontal-tat1 configurations are .presented in figures 6 to 25. he static longitud- stability at trim decreases with an increase in trim lift coefficient for tail positiona above the wing-chord plane (figs. 6 to X) and figs.: 23 to 25) and increases with an increase in trim lift coefficient for tail

15、positions below the wing- chord plane ( figs. 21 and 22) - - paper is concerned with figwee 26 to 45. The lift-curve slope and Longitudinal Stability I f I I Effect of tail le-h and hewt. - For convenience the basic data at t.t ,= O0 of figures 6 to 22 have been replotted - in figures 26 and 27. Fro

16、m figures 26 and 27 it can .be seen that the wing-fuselage cdm- bimtion is stable through- the lift-coefficient range for the test . ceder-of-gravity position. The data. of figures 26 and 27 also indicate that addition of. the horizontal tail (10 percent of the wing area) to the wing-f (fig. 33) is

17、large. Conversely, an increase in (qt/q), at.moderate and high angles of attack can magnify the instability caused by high t values of .ace/ whereas, at lift coeffi- and thus the effects of aspect ratio and sweep-are fnseparable. 4 height, area, and aspect ratio on the control effectiveness paramete

18、r C . The position of the center of gravity for each configuration of figures 43 and 44 may be obtained from the table in the section elrtitled “Longitudinal Stability.“ The Centers .of gravity for the conffguratiogs of figure 45 are presented subsequently in this section. mcL * mit I Effect of tail

19、 length and height.- An increase in lift coefficient produces only small changes in tlie values of anh c up to I c=2, mi+. I about maximum lift coefficient for each model configuration (fig. 43) . The best tail poaition with regard to static longitudinal stability I through the lift-coefficient rang

20、e was = -0.06 and = = 200; whereas the maximuu pitching-moment effectiveness through the lift- coefficient range was obtained at = 0.50 and whereasat high lift coef- I i ficients the difference amounts to about 23percen-k .The position for maximum C, . is one, howeer, where severe instability occurs

21、 at it - t I. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-moderate lift ,coefficients. (See fig. 29.) A tail position of. -5 = 0.25 C . and height generally C . The value .of C, =it -% about direct proportion to summarized Fn f i;ure 44- Change a

22、 in tail produce only small changes in the value of increases wLth an increase in tail length in the tail length and increases slightly with an increase in tail-height. Trends similar to those of the- present paper were indicated in the prevfously mentioned British investigation oFa 45.triaar-wing m

23、odel- having a separate-all-movable tail. In that investigation, however, only two tail. lengths were investigated. Effect of tail area and aspect ratio. - The data presented in fig- ure 45 are also for c = -0.10 at CL = 0 -and the centers of gravity for the configurations are as follows : % Configu

24、ration I 1 Center of gravity (percent E) 1 I f I1 I 30.6 All-movable tails 33.5 . 36.5 29.6 I II Constant-chord flaps Tip controls 29.2 I 27.4 An increase in tail.area from 5 to 15 percent of the wing area causes a proportional increase in CLFt . and C (fig. 45(a) which are about constant up to maxi

25、rmun lift coefficient. Reducing the aspect rat-io of the 5-percent-area tail from 2.3lto 1.07 causes a decrease in CLi and Cm which is constant up to XTQUIQ lift coefficient. =t t it tr f Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-A comparison o

26、f the effectiveness at CL = 0 of the all-movable 3 tails of the present investigation with the constant-chord flaps of. reference 1 and the tip controls of reference 3 is presented in figure 45(b.) for C = -0.10. Each of the controls was tested -on a wing of identical geometry. The all-movable tails

27、 produce a Slightly smaller change in lift with control deflection C than the .tip controls (which ie desirable) and, as would be .expected, a much smaller change in lift with control deflection than the constant-chord flaps. From a standpolnt of pitching-moment effectiveness C .the u- . movable tai

28、ls Le about twlce as effective as the tip controls asd are *L Lit mit about 20 percent less effective than the constasrt-chord flaps. A low-speed inyestLgation of the static longitudinal stability and control characteristic of a 6oo triangular-wing model having various all-movable horizontal taile h

29、as indicated the followi.ng conclusions: I ? 1. At-high angles of attack large increases in the rate of change . of effective downwash angle with angle of attack caused large decreases - I in the static longitudinal stability of most of tk. configurations. The hfgh-forward and low-rearward tail posi

30、tions were least affected by changes in downwash angle with angle of attack and, consequently, these positions had the most favorable stability characteristice. 2. For one position, a,n Jacob H.: Low- Speed Static LongTtudind Stability and Control Characteristics of - RM L5lD20a, 1951. I. a 60 Trian

31、gular-Wing Model Having Half-Delta Tip Colrtrols. WA 4. Bates, William R. : Low-Speed Static Longitudinal Stability Character: istics of a Canard Model Having a 60 Triangular Wing and HorizoKtal Tafl. MACA RM L9Hl7, 194. 5. Gaodman, Alex, and Jaquet, Byron M.: Low-Speed Pttching Derivatives of Low-A

32、spect-Ratio Wings of Triangular and Modified Triangular Plan Forms WA RM L50C02, 1950. 6. Jaquet, Byron M., . and Brewer, Jack D. : Effects of Various Outboard and Central Fins on Low-Speed Static-Stability and Rolling Character- istics of a .Trimgdar-Wing Model- XACA RM 918, 1949. 7. Silverstein, A

33、be, and White, Janies A.: Wind-Tunnel Interference with Particular Reference to Off-Cerrter Positions of the Wbg and to the Dawnwash -at the Tail. NACA Rep. 547, 1936. 8. Gillis, .Clarence L., Polharmzs, Edward C., and Gray, Joseph L., Jr.: Charts for Determining Jet-Boundary Correctfons For Complet

34、e Models in 7- by 10-Foot Closed Rectangular Wind Tunnels. NACA ARR L5G31, 1945 9. Herriot, John G.: Blockage Corrections for Three-Dimensional-Flow Closed-Throat Wind Tunnels, With Consideration of the Effect of Compres = 0.25; - = 1.25. Provided by IHSNot for ResaleNo reproduction or networking pe

35、rmitted without license from IHS-,-,-I “ c Figure. 5. - Lift and pitching-momen% characteristics of - model components. I I Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-! I Angle of attack, E, deg k 0 o , U . . . . . Provided by IHSNot for ResaleN

36、o reproduction or networking permitted without license from IHS-,-,-. . . . . . . . . . . 1 #I .t Figure 7.- Longitudinal stability and control characteristics of a 60 triangular-wing model having a triangular all-mvable tail. %. . W iu Provided by IHSNot for ResaleNo reproduction or networking perm

37、itted without license from IHS-,-,-. . . -4 0 4 8 12 16 20 24 28 32 36 0 -.04 -.08 :I2 516 :20 24 Angle of attack, E, deg Pltchtng-moment coeffment, C, E i2 Figure 8.- Longitudinal stability vd control characteristics of a G 60 triangular-wing model having a triangular all-movable tail. H2- i d “ t

38、1 I Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-I OB .W 0 -.04 -.OB :12 516 720 :24 728 Angle of attack, E, deg Ptrmg moment coeffmn4 C, Figure 9. a. Longitudinal stability and control characterietlce of a . . 60 triangular-wing 4. I. UI lu Provi

39、ded by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-N cn I b I . . . . Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-. Angle of wftock, , deg Ptfchmg-moment meffmmt, C, I. Figure U.- Longitudlnal stability a

40、nd control characterlatics of a 60 triangulax-wing model having a triangular all-movable tail. %. 1 - - . Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-I An of attack, (X, deg Figure 12.- Longitudinal stability and control char&teristics of a 60 tr

41、iangular-vug We1 having a triangular all-movable tail. %. . I Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-I I I . Figurg 13 .- Longitudinal stability &d control characteristics of a 60 . triangular-wing model having a triangular all-movable tall. Q. . Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-