1、*. - “. -. NACA RESEARCH MEMORANDUM LOW-SPEED INVESTlGATION OF TKE EFFECT OF SEVEXAL FLAP AND SPOILER AILERONS ON THE LATERAL CHARACTZRJSTICS OF A 47.5 SWEPTRACK-WING - FVSELAGE COMBINATION AT A RJENOLDS NUMBER OF 4.4 x lo6 By Jerome Pasamanick and Thomas B. Sellers L Langley Aeronautical Laboratory
2、 Langley Air Force Base, Va. I NATIONAL ADVISORY COMMITTEE FOR AERONAUTICS WASHINGTON December 8, 1950 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-1 . I NACA RM LYJ20 LOW-SPEED INVESTIGATION OF TE3 EFFECT OF SEVERAL FLAP, AND SPOiXER DONS ON TEE
3、CHARACTERISTICS OF A 47.5 SWEPTBACK-WING - FUSELAGE CWINATIOH AT A RFYNOLIIS “BER OF 4.4 X lo6 By Jerome Pasdck and Thomas B. Sellers An investigation was mde in the Langley Azll-scale tunnel of- the low-speed lateral CharaCteriEtiC8 of a 47.5O sweptback-wfng - fiselage combination with several flap
4、 and spoiler aileron amaagements at a Reynolds number of 4.4 x lo6. The wing had an aspect ratio of 3.4, a taper ratio of 0.51, and NACA 641AU2 airfoil sections. The results indicated that the rolling effectiveness of small-span ailerons located inboard of the wing tips were greater than the effecti
5、veness of equal- span ailerons located at the wing tips. At lift coefficients near the stall, the aileron effectivenese of the model with thick trailing-edge contour ailerons was essentially the same as the aileron effectiveness .of the original contour ailerons. In general, the spoilers located in
6、the region of the plane of symmetry developed greater rolling moments than equal-span spoilers located at the wing tip. Increasing spoiler projection increased the . spoiler rolling moments and spoiler chordwfse location had no appreci- able effects on the rolling moments of the model at the angle o
7、f attack corresponding to 85 percent of the meudmum lfft. IMTROIXJCTION Latersl-control devices emispan stations. The flaps deflected The spoiler height8 *ea- tigated included projectiane of 2 percent, 5 percent, and 10 percent of the wing chord measured in thus, 17.8 percent of the spoiler TESTS Th
8、e tests were made on the six-component balance system of the - Langley full-scale tunnel at a Reynolds nmber of 4.4 x 10 and a Mach 6 number of approximately 0.07. Data were obtained at zero pw Over a range of angles of attack from small negative angles through maximum. - lie. RESULTS c All the data
9、 have been corrected for blocking effecta, stream dine- ment, and approximate wing-support interference. The drag and angle-of- attack data have been corrected for Jet-boundary effects (as determined from the straight-wing nethod of reference 6) but although the corrections for the effects of the Je
10、t boundary on the moment data have not been -plied they are considered neglfgible. The aileron-effectiveness pmameter Ctga was obtained by measuring the slopes of rolling-moment curve8 from 0 to ma . total aileron deflectL,an for several values of angle of attack below the maximum lift. All wing con
11、figurations, without ailerons or spoilers, elmibited small values of rolling-moment and yawing-mament coefficients 86.8 result of the slight irregularitfes of the model construction, model test mounting, and tunnel air flow. The data reported here have not been correctedfor the initial out-of-trim r
12、oll or yaw of the model when the controls were neutral. In order to facilitate the diacussian of results, the data are arranged in the following order of figures. Figure 4 presents the static Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-6 - NACA F
13、M L50J20 longitudinal characteristics of the model with and without flaps as obtained from reference 5. The effects of aileron span and trailing- edge thickness on the aileron-effectiveness parameter are presented in the summary curves of figures 5 and 6 .for the wing with and without flaps. Figure
14、7 shows the effects of spoiler span on the rolling characteristics of the plain- and flapped-wing configurations, and figure 8 presents a comparison between the estimated and measured rolling coefficients of the model with a partial-span spoiler. The rolling characteristics of a full- span spoiler w
15、ith various projection heights are given in figure 9 over a range of angles of attack. The effects of spoiler chordwise location on the lateral characteristics of the model having a partial-span spoiler are given in figure 10. Figure 11 compares the lateral characteristics of the model equipped with
16、 several ailerons and spoilers. The basic aero- dynamic characteristics of the model having ailerons of various spans, spanwise locations, and trailing-edge thicknesses are given in figures 12 to 15, and the basic spoiler data are presented in figures 16 to 18 for the plain- and flapped” configurati
17、ons. Figure 19 presents the effecta of a perforated partial-span spoiler on the aeroaynamic characteristics of the model. DISCUSSION OF RESULTS Aileron Control Characteristics Effect of aileron span and- spanwise location.- As might be expected, the results given in figure 5 show that the aileron-ef
18、fectiveness parameter C increased with aileron spas with the greatest value of 8, Z8a being obtained at the lowest angle of attack. The aileron effective- ness at the angle of attack corresponding to 85 percent of the maxinun lift coefficient, which shall be referred to throughout the discussion ina
19、smuch as it is usually considered the higheet landing approach lift coefficient, was approldmately 75 percent of the maximum value of C2 6a obtained for each wing configuration. For the plain wing at 0.8% Lmax the aileron effectiveness of equal-span ailerons 0.225 located at the wing tip or inboard
20、of the 0.779 -span station -8 -0.00024 or -0.00030, respectively. Tuft observations indicated the flow Over the rear and outboard sections of the wing to be unBteady with the effect being more pronounced near the wing tip. Increasing the aileron spas to 0.4% (outboard end located at the wing tips) r
21、esulted in a value of CzEa of c 3 2 -0.0009. This value is more than double the vdue of Cz Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-from the 0.2e - span aileron located at the wing tip. The increment of aileron effectiveness produced by each e
22、qual-span aileron (0.2251;) at the spanwise locations iwestigated can be added to produce a total Cz 6a for the 0.4% - span aileron at 0.85. At lower angles of attack, however, this procedure slightly overestimates the effectiveness of the 0.4% - span ailerons. The aileron effectiveness (-0.0001) at
23、 0.8sk of the 0.4% -span ailerons located on the aapped-wing corngumtione were essentially the aame as the results for the plaln wing. The results given in figures 12 to 14 show the variation of rolling- moment and yawing-moment coefficients to be linear with total aileron deflection for the model c
24、onfigurations tested. In general, aileron deflection produced adverse yaw for all wing configurations with the effect becoming more adverse with increasing lift coefficient and aileron deflection. The lift and pitching-moment characteristics were essentially unaffected by the deflection of the ailer
25、ons and the increment of drag coefficient (fig. 15) was srnall compared to the total model drag at a lift coefficient of approximately 0.85Chx. , Effect of aileron trailing-edge thickness.- The results given in references 7 and 8 show that inmrovements Fn the rolling characteristics at both high and
26、 low flight speeds of sweptback wings c thereby less lift and larger rolling moments would result. A method was outlined in reference 2 to estimate the rolling effec- tiveness of partial-span spoilers from the data of inboard and outboard spoiler segments. This method has been applied to a partial-s
27、pan spoiler used in the present investigation and the estimated results are compared in figure 8 to the measured rolling-moment coefficients of the 0.6$ -span plain spoiler. The results show good agreement between the estimated and measured values of Cl throughout the angle-of-attack range. Figures
28、16 to 18 show that the spoilers resulted, as was expected, in decreased- lift, increased drag, and unstable.pitching-moment trim shifts at the angles of attack investigated-. The unfavorable spoiler effects on the longitudinal characteristics increased with spoiler span and were greatest for the fla
29、pped-wing configurations. The tip-fixed spoilers produced favorable yawing characteristics throughout the angle- of-attack range for all spoiler span6 and wing configurations. The root- fixed spoilers, however, resulted in adverse y-aw for the smaller span spoilers with the greatest effects occurrin
30、g at the higher angles of attack and for the flapped“ configurations. Effect of spoiler projection.- For the basic wing configuration the rolling moments produced by the spoilers are nearly linear for spoiler projections up to about 0.05 (Mg. 9). For greater proJections up to O.lOc, the spoiler effe
31、ctiveness decreased and“the maximum value of C2 was attained at an angle of attack of 6.g0. At 16.1O, which is approxi- mately the angle corresponding to 0.8jCk, the rolling-mcanent coeffi- cient produced by the gpoiler was 77 percent of the maximum value obtained. Althou that 18, the rearward-locat
32、ed spoiler produced greater roll than the %-percent chordwise-located spoiler. Similar results were obtained on several 42O sweptback wings with NACA 641-112 airfoil sections and are reported in references 2 and 4. A few explo-tory testa were conducted to determine the effects of a perforated spoile
33、r on the aeroaynamic characteristics of the model with and without flaps. In general, the data of figure 19 indicate no appre- ciable differences in the lateral or longitudinal characteristics of the model at high lift coefficients with either the plain or perforated type of spoiler. As uas previous
34、ly noted, at the high angles of attack the spoilers were located in regions of disturbed flow and their effective- the perforated spoiler produced greater rolling moments than the plain spoiler uhen located at the 0.Wc station. The air flow through the perforations may have resulted in a greater det
35、rimental. effect on the L ness was limited. In the low and moderate angles of attack, however, Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-10 - NACA RM L50J20 section pressure distribution than the plain-type spoiler. The decreased drag, due to s
36、poiler perforation, resulted in less favorable yawing momenta at the low and moderate angles of attack; however, both types of spoilers produced adverse yaw at the stall. As a result of the decreased lift and drag in the angle-of-attack range below the stall, the perforated spoilers caused positive
37、longltudhal trim shifts for all configurations. Comparison of Ailerons and Spoilers In order to compare the lateral-control effectiveness of ailerons and spoilers, a brief comparison of the lateral-control characteristics of the model with an aileron (0.4% span) and two 0.10 * tip-fixed spoilers (0.
38、85% and 0.4% spm) is presented. It should be noted that there are no hinge-mknt data available and that a complete evalua- tion would require comparisons of such data. For the basic wing configura- tion, figure 11 shows that a totalaileran deflection of 48O would be required to produce rolling momen
39、ts comparable to those produced by the 0.85% -span spoiler between 70 and 14 angle of attack and greater rolling moments below and above this angle-of-attack range. If the aileron deflection angle was limited to 30, however, the rolling moments Of the spoiler configuration would be much greater than
40、 the rolling moments of the aileron throughout the angle-of-attack range. The rolling c moments produced by the ailerons may also be decreased as a result of the adverse yaw (fig. ll(b) wbich occurred for dl aileron-control deflection angles. For the confipration with extensible leading-edge flaps,
41、ccmbined with plain trailing-edge flaps, the rolling moments of a 0.85$ -span spoiler was greater than the rolling effectiveness of the half-span aileron at the largest deflection angle (56) investigated. A amaller span spoiler (0.9) was, therefore, considered and it can be seen that 32 of .aileron
42、deflection would produce rolling moments simflar to that of the partial-span spoiler throughout the angle-of-attack range. Com- parison based on an angle of attack corresponding to 0.8% , however, indicates that the spoiler rolling moment is approximately %= 5 percent lower than that for the aileron
43、 deflected 56O. The difference in rolling moment between the aileron and the epoiler may be reduced, inasmuch as the adverse yaw produced by the ailerons would effectively decrease the aileron rolling capabilitiee. J Provided by IHSNot for ResaleNo reproduction or networking permitted without licens
44、e from IHS-,-,-NACA RM 5020 - 11 CONCLUDING REMARKS The results of the Langley full-scale-tunnel investigation of a 47.5O sweptback-wing - fuselage combination with several lateral-control devices are summarized as follows: 1. The aileron effectiveness of small-span ailerons located inboard. of the.
45、 77.5percent-span station was greater than the aileron effective- ness of equal-span ailerons located at the wing tips. For largespan ailerons, the aileron effectiveness at 85 percent of the maximum lift was equivalent to the sumof the effectivenesa of the component aileron spans. 2. The aileron eff
46、ectiveness. of the model with the thick trailing- edge and original contour ailerons wae essentially the same in the high angle-of-attack range. The drag increments near the stall due to the thick ailerons were small. 3. n general, for the angles of attack investigated, spoilers located in the regio
47、n of the plane of symmetry developed greater rolling moments than equal-span spoilers located at the wing tip. The addition of the spoilers resulted in positive longitudinal trim shifts at the angles of attack investigated. . 4. Increasing spoiler projection increased the rolling moments through mos
48、t of the spoiler-projection range investigated. 5. The rolling moments produced bya partial-span spoiler located at the midspan were essentially independent of spoiler chordwise location at the angle of attack corresponding to 85 percent of the maxLmum lift. A perforated spoiler did not change the l
49、ateral or longitudinal charac- teristics of the model at the high angles of attack. 6. The comparison between aKLera and spoilers shows that large deflection angles of a half-span aileron would produce.rolling moments . equivalent to a moderate-span spoiler located in the region of the plane of symmetry. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,
