1、Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-1. Report No. NASA CR-1783 4. Title and Subtitle FULL-SCALE WIND TUNNEL TESTS OF A LOW-WING,SINGLE- ENGINE,LIGHT PLANE WITH POSITIVE AND NEGATIVE PROPELLER THRUST AND UP AND DOWN FLAP DEFLECTION 7. Auth
2、or(s) E. Seckel and J. J. Morris 9. Performing Organization Name and Address Princeton University Princeton, New Jersey 12. Sponsoring Agency Name and Address National Aeronautics and Space Administration Washington, D. C. 20546 2. Government Accession No. I 5. Report Date August 1971 6. Performing
3、Organization Code 8. Performing Organization Report No. Princeton U. Report No. 922 10. Work Unit No. 736-01- 10-01-00 N A S 1-9443 11. Contract or Grant No. 13. Type of Report aRd Period Covered Contractor Report 14. Sponsoring Agency Code 3. Recipients Catalog No. I 17. Key Wprds (Suggested by Aut
4、hor(s) Low-wing light plane Forward and reverse thrust Up and down flap deflection Full-scale tunnel tests 18. Distribution Statement Unclassified U n limited 16. Abstract Full-scale wind-tunnel data for a low-wing single-engine light airplane, with up and down flap deflections and a range of negati
5、ve through positive propeller thrust, are presented. The data are analyzed to determine the effects of flap deflection, propeller thrust and angle- of-attack on the aerodynamic characteristics of the airplane. Longitudinal and lateral - directional static stability, control, and trim characteristics
6、 are considered in some detail. 19. Security Classif. (of this report) 20. Security Classif. (of this page) Unclassified Unclassified 21. NO. of Pages 22. Price* 154 $3.00- For sale by the National Technical Information Service, Springfield, Virginia 221 51 Provided by IHSNot for ResaleNo reproducti
7、on or networking permitted without license from IHS-,-,-Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-FOREWORD The authors wish to acknowledge with thanks and admiration the part in this project of the wind-tunnel staff at Langley Research Center,
8、NASA. Messrs. Marion 0. McKinney, Jack Paulson, and Marvin P. Fink produced the needed data in the wind-tunnel tests; and by their interest, patience, and guidance, helped educate the participating group of Princeton students, The Princeton Department of Aerospace and Mechanical Sciknces stu- dents
9、who assisted the Langley staff in the wind-tunnel test program were C. W. Staley, P. W. Howard, and R. C. Hubenet, graduate students; and H. W. Davis, P. S. Basile, and W. K. Woodrow, seniors The analysis of the aerodynamic data has been largely done as Inde- pendent Work by two groups of seniors: P
10、. S. Basile, G. F. Kline, S. F. Gripper; and H. W. Davis, J. J. Morris, P. E. Griffin. The authors greatly appreciate and freely acknowledge the importance and advantage of all this student participation. The wind-tunnel test project, including analysis of the test data, is Phase I of a larger proje
11、ct involving extensive automatic control installa- tions and other modifications to another aircraft of the same type, and ultimately flight tests on flying qualities for landing. is supported at Princeton University by Langley Research Center under Contract No. NAS 1-9443. The technical monitor for
12、 LRC is Mr. Harold Crane. The whole program iii Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SUMMARY Full-scale wind-tunnel data for a low-wing, single-engine, light plane, with up and down flap deflections and negative through positive propeller
13、thrust, are presented. flap deflection, thrust and angle -of -attack on the longitudinal and lateral- directional static stability, control eff ectivene s s, and trim char aot er istic s. These data are analyzed to determine the effects of Although the interacting effects of these variables are stro
14、ng and some- times irregular, the factors limiting the use of large negative thrust are probably loss of elevator effectiveness for longitudinal characteristics and rudder effectiveness for directional characteristics. V Provided by IHSNot for ResaleNo reproduction or networking permitted without li
15、cense from IHS-,-,-Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-*TABLE OF CONTENTS FOREWORD iii SUMMARY V LIST OF SYMBOLS ix INT R OD U C T IO N 1 2 4 5 6 6 7 Maneuvering Stability, Nm 8 9 10 11 11 The Light Single -Engine Airplane The Wind -Tunne
16、l Program 2 Wind -Tunnel Data Reduction and Aerodynamic Parameters . Pitching Moment Stability, Trim and Control, Cm vs CY and 6e Stabilizer Effectiveness, Cm for two it, and Tail-off Elevator and Stabilizer Effectiveness as a Function of Power Effective Downwash Angles 7 Static Trim, Cm vs CL Direc
17、tional Stability, Cn vs $ Rudder Effectiveness, Cn vs 6, 9 Dihedral Effect, C4 vs $ Roll Control, C4 vs 6, C 0 NC LUSIO NS REFERENCE 12 TABLES 13 FIGURES 27 vii Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Provided by IHSNot for ResaleNo reproduct
18、ion or networking permitted without license from IHS-,-,-LIST OF SYMBOLS cD cL c aC / a$; per degree aC / a6a; per degree Pitching moment coefficient , per degree Static stability derivative; -. - . acnl a6 Tail effectiveness; - acm , per degree a it Static stability derivative Yawing ,mo,ment coeff
19、icient Directional stability; - 8% ; per degree a$ acn Rudder effectiveness; - ; per degree 36 r T Thrust coefficient ; - Aileron deflection angle; degrees qs Elevator deflection angle; degrees Flap deflection angle; degrees Rudder deflection angle; degrees Tail incidence angle; degrees ix Provided
20、by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-a Angle of attack; degrees do / da T.O. , L/D qt S D c. g. Nnl degrees Angle of sideslip; degrees Downwash angle; degrees Downwash factor Horizontal tail off Lift to drag ratio Tail efficiency Wing area or prope
21、ller disk area; ft” Propeller diameter Elevator effectiveness; Cmg/ Cm. Dihedral angle; degrees Center of gravity position It Maneuver point Position of center of gravity on mean aerodynamic chord Airplane density factor; - m psc Distance from c. g. to horizontal tail; ft Mean aerodynamic chord; MAC
22、; ft I X. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-FULL-SCALE WIND TUNNEL TESTS OF A LOW-WING, SINGLE-ENGINE, LIGHT PLANE WITH POSITIVE AND NEGATIVE PROPELLER THRUST AND UP AND DOWN FLAP DEFLECTION By Edward Seckel and James J. Morris Princeto
23、n University INTRODUCTION Early in 1969, it was proposed by Princeton University to equip a light single -engine aircraft for variable stability with separate control of lift and drag by a modified lift-flap and a blade pitch control propeller. The special flap would be the standard flap unit, but w
24、ith the hinge position altered, and provision for up as well as down deflections. In con- tour and shape, the flap being the same as the aileron, the new hinge posi- tion was chosen for convenience to be in line with the aileron hinge (see Fig- ure 2). hinge brackets, attachments , and the installat
25、ion. This expedient detail would greatly simplify the detail design of The blade pitch propeller was to be used for automatic control of thrust to simulate arbitrary drag properties, including large drag, low L/D vehi- cles. This would involve large amounts of negative thrust, and rapid changes of t
26、hrust due to automatic command of the propeller pitch angle. It was anticipated that both the up-and-down flap and the negative thrust propeller would cause complicated and unpredictable aerodynamic ef - fects which would interfere with their proper use in simulation unless at least major interferen
27、ce phenomena could be identified quantitatively by wind- tunnel test data. of NASA that the airframe, with the modified flap and propeller, would be tested in the Full-Scale Tunnel to furnish the required data. motor was to be installed by the wind-tunnel staff to facilitate power control in the tun
28、nel, and simplify general operating procedures. Accordingly, it was agreed with Langley Research Center An electric Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-The wind-tunnel program was done in August and September of 1969, with a group of grad
29、uate and undergraduate Princeton students assisting the wind-tunnel staff. A very complete and definitive set of aerodynamic data data was obtained, as would be required ultimately in the flight program. The Princeton students, of course, benefitted tremendously by the experi- ence and contact with
30、research operations and personnel at LRC. During the academic year 1969-70, a group of students at Princeton extensively analyzed the wind -tunnel data to find basic aerodynamic para- meters of the airplane and the various special controls. is scarcely complete - in fact, it will probably continue f
31、or special effects through the life of several flight projects - but the substantial results so far achieved are presented in this report. This data reduction The Light Single -Engine Airplane The dimensional and typical inertial properties of the aircraft are shown in Figure 1 and Table 1. accompan
32、ying large -scale drawing of the outboard flap section. Details of the modified flap are shown in the The Wind -Tunnel Program The wind-tunnel tests involved some 365 runs - each “run“ consisting of readings over a complete range of angle of attack from -4 to 22 degrees. Among the 365 runs, there we
33、re variations in tail incidence (i ), including t tail-off; elevator angle (6 ); flap deflection (6 ); thrust coefficient (T I), including propeller-off; aileron deflection (6 ); rudder angle (6 ); and side slip angle (6). e f C a r A table of runs is given in Table 2 for detail reference. The scope
34、 and shape of the tests conditions can better be appreciated, however, by a short description of the test program. 2 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-The sets of conditions for the longitudinal parameters can best be de- For a flap ang
35、le of zero degrees, 66 runs were made scribed in two parts. using all combinations of 6 values of T I (nominally .215, .095, 0, -. 05, -. 13, -. 175), 2 values of i (55 ), tail-off, and 5 values of 6 -10 , -17 , -23 for i -5 and 11.3, Oo, -10 , -20 , -30 t t For flap angles of rt20 , *30, 132 runs w
36、ere made using all combinations of 3 values of T (nominally -215, 0, -. 175), 5 values of 6 (17.9O, Oo, -10 , -17 , -23O), 2 values of i C 0 (17.9O, Oo, for i = +5 ). e 0 0 0 0 0 0 0 0 t 0 C e 0 0 (*5O), and tail-off. t For aileron characteristics runs (cy from -4 to 22 degrees) were made (24.4O, 12
37、.2, Oo, -8.8 , -18. 8 ) at 6e = 6 = 6 =$ = 0 0 for five values of 6 T = 0, and i = -5 . Runs were also made for three values of 6 12.Z0, Oo), at 2 values of 6 a rf 0 (24.4, a =$ = T = 0. 0 C t (f30) for i = -5 , 6 = 6 er C f t The scope of the wind tunnelruns to determine the effect of yaw angle and
38、 rudder inputs is more complex than that for the longitudinal or aileron runs. to indicate combinations of $ and 6 represents runs for 3 values of T I (nominally .215, 0, -. 175) for 6f = 0. The + represents runs for 4 values of T (nominally 095, -. 05, -. 09, -. 13), also for 6 = 0. Finally, the 0
39、represents runs for 3 values of T (nominally .215, 0, -. 175) and 4 values of 6 In all of these, i =-5, 6 =6 =O. t ea The combinations are shown in the matrix below using three symbols for different T and 6f. The X r C C C C 0 f (f20, *30 ). f 0 0 6r (deg) 13.2 7 0 -9 -17.5 15 X X 10 X x -to X 5 X $
40、 0 X xto xto X -5 X -10 X xto X -15 X X X 3 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-In the actual tests the remote control of propeller blade pitch angle was rather inaccurate and inconsistent - so that between runs at the same nominal T ther
41、e were considerable variations of actual T I. The true values of T were deduced in the data reduction by subtracting the overall effective C (with propeller operating) from a corresponding CD read in runs with the propeller removed. greatly complicated certain aspects of the data reduction, as expla
42、ined in the next section. C C C D prop off The variations of T within runs C Wind -Tunnel Data Reduction and Aerodynamic Parameters The reduction of the basic wind-tunnel data is described and discussed in the following paragraphs. ures 3 through 20. The results are presented graphically in Fig- Lif
43、t curve, CL vs a. - Lift curves, CL vs cy , for the five flap de- flections tested, and for positive, negative, and zero thrust coefficients are shown in Figures 3 a, b, c. thrust are about what might be expected. tically the same as for 20 deflection, separation occurs on the bottom surface, limiti
44、ng the negative lift increment. the flap at negative deflections. be, like those of a typical Frise aileron. The lift increments due to flap deflection and up flap is prac- 0 The lift for 30 0 0 up flap, and it may be concluded that for 30 up This may be caused prematurely by the protruding nose of
45、The shape is, and characteristics ought to The lift curves of Figure 3, discussed above, are derived from fair- ings of the test data points presented in Figures 16 (a to e). done in carpet fashion, with the independent carpet variables cy and T I. This was to facilitate the plotting and interpolati
46、ons necessitated by varia- tions in T from nominal, constant values. scatter can be appreciated by observing the data points in the carpets. Some scheme like this was quite necessary in order to regularize T in the final The latter are C The magnitude of the T C C C 4 Provided by IHSNot for ResaleNo
47、 reproduction or networking permitted without license from IHS-,-,-data presentation. The scheme, however, is not really feasible near Lmax area, the curves of Figure 16 are less precise and shown dotted to indicate reduced confidence. and the stall, where the lift curves are quite irregular. In tha
48、t Pitching Moment Stability, Trim and Control, C vs (Y and 8 The longitudinal static stability and trim of the light single -engine air - m e craft are presented in the various parts of Figure 4, with Cm a function of r and 6 . The graphs are presented in carpet style, to facilitate interpola- tions. up and 17.9 deg down for i = -5 for i = 4-5 . There are fifteen of these carpets, for five flap deflections and three thrust coefficients. e In the test program, t
