1、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-,-,-NOTICETHIS DOCUMENT HAS BEEN REPRODUCEDFROM THE BEST COPY FURNISHED US BYTHE SPONSORING AGENCY. ALTHOUGH
2、 ITIS RECOGNIZED THAT CERTAIN PORTIONSARE ILLEGIBLE, IT IS BEING RELEASEDIN THE INTEREST OF MAKING AVAILABLEAS MUCH INFORMATION AS POSSIBLE.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-REPORT 927.APPRECIATION AND PREDICTIONOF FLYING QUALITIESBy WI
3、LLIAM H. PHILLIPS/_ Langley Aeronautical Laboratory_ Langley Air Force Base, Va.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-National Advisory Committee for AeronauticsHeadquarters, 1724 F Street NW., Washington 25, D. C.Created by act of Congress
4、 approved March 3, 1915, for the supervision and direction of the scientific studyof the problems of flight (U. S. Code, title 50, sec. 151). :Its membership was increased from 12 to 15 by actapproved March 2, 1929, and to 17 by act approved May 25, 1948. The members are appointed by the President,a
5、nd serve as such without compensation.JEROME C. HUNSAKER, SC. D., Massachusetts Institute of Technology, C_airmanALEXANDER WETMORE, So. D., Secretary, Smithsonian Institution, Vice Chairman:HoN. JO_N R. ALXSON, Assistant Secretary of Commerce. DONALD L. PUTT, Major General, United States Air Force,D
6、ETLEV W. BRONK, PH.D., President, Johns Hopkins University. Director of Research and Development, Office of the Chief ofKARL T. COMPTON, PH. D., Chairman, Research and Development Staff, Materiel.Board, Department of Defense. JOHN D. PRICE, Vice Admiral, United States Navy, Vice Chief ofEDWARD U. CO
7、NDON, PH. D., Director, National Bureau :of“ Naval Operations.Standards. ARTHUR E. RAYMOND, SC. D., Vice President, Engineering,JAMES H. DOOLITTLE, SC. D., Vice President, Shell Union Oil Douglas Aircraft Co., Inc.Corp. FRANCIS W. REICHELDERFER, Se. D., Chief, United StatesWeather Bureau.R. htl. HAG
8、EN, B. S., Director of Engineering, Allison Division, HON. DELOS W. RENTZEL, Administrator of Civil Aeronautics,General Motors Corp. Department of Commerce.WILLIAM LITTLEWOOD, M. E., Vice President, Engineer!ng , HOYT S. VANDENBERG, General, Chief of Staff, United States AirAmerican Airlines, Inc. /
9、 :_: :i . : : : Force.THEODORE C. LONNQUEST, Rear Admiral, United States Navy, THEODORE PI WRIORT, SC. D., Vice President for Research,Deputy and Assistant Chief of the Bureau _)f Abronautics Cornell University., ._ . ., .: . j lj_tHvon L. DRYDEN, PH.D., Di?ector JoHN F. VICTORY, LL. M., Executive S
10、ecretary “iJOHN W. CROWLEY, JR., B. S., Associate Director for Research E.H. CHAMBERLIN, Executive Officer _:HENRY J. REID, D. Eng., Director, Langley Aeronautical Laboratory, Langley .Field, Vs. l_S_ITH J. DEFR_,NCE, B. S., Director, Ames Aeronautical Laboratory, Moffett Field, Calif.EDWARd) R. SHA
11、RP, SC. D., Director, Lewis Flight Propulsion Laboratory, Cleveland Airport, Cleveland, OhioTECHNICAL COMMITTEESAERODYNAMICS OPERATING PROBLEMSPOWER PLANTS FOR AIRCR2tFT INDUSTRY CONSULTINGAIRCRAFT CONSTRUCTIONCoordination of Research Needs of Military and Civil AviationPreparation of Research Progr
12、amsAllocation of ProblemsPrevention of Duplicationi Consideration of InventionsLANGLEY AERONAUTICAL LABORATORY LEWIS FLIGHT PROPULSION LABORATORY AMES AERONAUTICAL LABORATORY _,_ Langley Field, Va. Cleveland Airport, Cleveland, Ohio Moffett Field, Calif.i Conduct, under unified control, for all agen
13、cies of scientific research on the fundamental problems of flight/ ,OFFICE OF AERONAUTICAL INTELLIGENCEWashington, D. C.Collection, classification, compilation, and dissemination oj scientific and technical information on aeronauticsnProvided by IHSNot for ResaleNo reproduction or networking permitt
14、ed without license from IHS-,-,-CONTENTSPage PageSUMMARY . 1 DISCUSSION OF TYPES OF CONTROL-SURFACEINTRODUCTION . 1 BALANCE:LONGITUDINAL STABILITY AND CONTROL CHAR- Importance of Control-Surface Balance . 17ACTERISTICS IN STRAIGHT FLIGHT: Plain Control Surface . 17STABILITY CHARACTERISTJCS IN STRAIG
15、HT FLIGHT _. 1 Balance Characteristics . 17Requirements and Definitions 1 Overhanging or inset_hinge balance . 17Methods of Obtaining Static Longitudinal Stability._ 2 Unshielded horn balance 17Dynamic Longitudinal Stability 3 Balancing tab . 17EFFECTS OF PROPELLER OPERATLON ANn POWER ON Beveled-tra
16、iling-edgebalance _ _ 18STABILITY - 3 Sealed internal balance . _ . 18Single-Engine Airplanes . 3 Other types of control-surface balance “ 18Multiengine Airplanes 5 Comparison of Various Balancing Devices . 18Jet-Propelled Airplanes . 6 DIRECTIONAL STABILITY AND CONTROLCONTROL CHARACTERISIICS IN STE
17、ADY FLIGHT . 6 CHARACTERISTICS:/ DETERMINATION OF NEUTRAL POINTS FROM FLIGHT DIRECTIONAL TRIM CHARACTERISTICS 19TESTS 9Stick-Fixed Neutral Point . 9 Requirements . _ . 19Directional Trim Characteristics for Single-EngineStick-Free Neutral Point 9 Airplanes . 20EFFECTS OF COMPRESSIBILITY ON TRIM AND
18、STABILITY_ 10 CHARACTERISIICS IN STEADY SIDESLIPS 22Effects of Compressibility on Various Airplane Corn- Requirements 22ponents . 10 Directional stability and control characteristicsExamples of Effects of Compressibility 11in sideslips_ = 22Reasons for Compressibility Effects 11 Pitching moment due
19、to sideslip . 22Dive-Recovery Flaps . 11 Side-force characteristics 22EFFECTS OF STRUCTURAL AND CONTROL-SURFACE DIS- Discussion of Equilibrium of an Airplane in a Steady_ORTION ON LONGITUDINAL STABILITY II.LONGITUDINAL TRIM CHANGES DUE TO POWER ANDFLAPS_ 12 Sideslip : 22Requirement 12 Typical Defici
20、encies in Sideslip Characteristics . 22Contributions of Various Airplane Components to theReasons for Trim Change with Flap and Power Con- Directional Stability 23dition , 12LANDING AND TAKE-OFF CHARACTERISTICS. 12 Directional stability of the fuselage . “ 23Requirement for Landing Characteristics 1
21、2 Propeller yawing moments 23Requirements for Take-Off Characteristics . 13 Wing yawing moments . 24Discussion of Ground Effect . 13 Yawing mon_ents from the vertical tail . 24LONGITUDINAL STABILITY AND CONTROL CHAR- Design Considerations for Prevention of Rudder Lock_ 24ACTERISTICS IN ACCELERATED F
22、LIGHT: Dihedral Effect 25Relations between Longitudinal Stability in Straigh t and in Requirements . 25Accelerated Flight 13 “ Definition of effective dihedral_ . 25Calculation of Stick Forces in Accelerated Flight _ 14 Influence of wing location, power, and sweepbackon effective dihedral 25Effects
23、of pitching the whole airplane to a higherangle Measurement of effective dihedral in flight 26of attack 14Effects of curvature of the flight path . 14 AILERON CONTROL CHARACTERISTICS:.Discussion of Factors Influencing Stick Forces in Accel- Requirements for Satisfactory Aileron Control . 27erated Fl
24、ight_ _ 15 Typical Aileron Control Characteristics . 27Distinction between Turns and Pull-Ups 15 Calculation. of Rolling Effectiveness 28Requirements for.Elevator Control in Accelerated Flight_ 15 Amount of Aileron Balance Required for SatisfactoryExamples of Stick .Force in Accelerated Flight on Di
25、fferent CharActeristics . 29Types of Airplanes . 15. Notes on Aileron Balance, Prise Ailerons, and Spoilers 30Means of ()htaining “Satisfactory Elevator Control Forces Adverse Aileron Yaw . 31in Steady Maneuvers . 15 Requirement for Limits of Yaw due to Ailerons . _ 31Stick Forces in Rapid Pull-Ups
26、16 Rolling Maneuvers in Accelerated Flight 31llProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-. IV CONTENTSPage Pa_STALLING CHARACTERISTICS: WIND-TUNNEL TESTS AND CALCULATION PROCE-Requirements forSatisfactoryStallingCharacteristics 32 DURES FOR DET
27、ERMINATION OF FLYING QUAL-DiscussionofTypicalStallingCharacteristics 32 ITIES ContinuedInfluence of Various Design Factors on Stalling Charac- SIMULATION OF POWER CONDITIONS Continuedteristics 32 , ; Selection of Model Propeller Blade Angle . 3Flight Conditions Leading to Inadvertent Stalling 33 Pre
28、paration of Operating Charts . 3Ground Looping . 33 Simulation of Propeller-Idling Condition 3CONTROL-FREE STABILITY OR SHORT-PERIOD WIND-TUNNEL TESTS FOR LANDING AND TAKE-OFF“OSCILLATIONS: CHARACTERISTICS 3Requirements for Longitudinal Motion_ 33 Wind-Tunnel Tests Employing a GroUnd Board . - 3Infl
29、uence of Design Factors on Short-Period Longitudinal . Simulation of Power for Take-Off Condition_-_ _2 “ 3Oscillations . : 34 Wind-Tunnel Test Procedure for Take-Off Condition_ 3Requirements for Lateral Motion 34 Computation of Ground-Reaction Moments . $Influence of Design Factors on Lateral Oscil
30、lations . 34 -Tricycle landing gear . _ . 3Relation between Rudder, Aileron, and Elevator Short- “Conventional landing gear . 3Period Oscillations - 35 DETERMINATION OF NEUTRAL POINTS_. - 3WIND-TUNNEL TESTS AND CALCULATION PROCE- Stick-Fixed Neutrai Point . “ _.DURES FOR DETERMINATION OF FLYING QUAL
31、- Stick-Free Neutral Point . _. _-_ 4ITIES:INTRODUCTION _ . L . 35 CONCLUDING REMARKS CONCERNING SELECTIONSIMULATION OF POWER CONDITIONS . - : 35 OF AIRPLANE CONFIGURATION TO SATISFY THECriterions of Similitude . 35 FLYING QUALITIES REQUIREMENTS . 4Variation of Thrust in Flight 35 APPENDIX-SYMBOLS_
32、_ . 4Calculation of the Variation of Thrust Coefficientwith Lift Coefficient for a Specific Airplane 36 REFERENCES . 4i. - . . .Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-,- REPORT 927APPRECIATION AND PREDICTION OF FLYING QUALITIESBy WILLIAUH. P
33、HILLIPSSUMMARY Different sets of specifications for satisfactory handlingcharacteristics have been prepared by various agencies as aThe material given in this report summarizes some oJ the result of the work done by the NACA. The requirementsresults of recent research that will aid the designers oJ
34、an for satisfactory flying qualities stated in this report do notairplane in selecting or modiJying a configuration to provide form a complete set and are not taken directly from anysatisfactory stability and control characteristics. The require- of the previously published specifications, but they
35、includements oJ the National Advisory Committee Jor Aeronautics for the more important requirements that should, in general, besatisJactory flying qualities, which speciJy the important sta- met by all types of airplanes. For more complete flying-bility and control characteristics of an airplane fro
36、m the pilots qualities specifications, references 2, 3, and 4 should bestandpoint, arc used as the main topics of the report. A dis- consulted.eussion is given o.f the reasons .for the requirements, o.f the The original lectures on wind-tunnel procedure and.factors involved in obtaining satisfactory
37、 flying qualities, ando.f the methods used in pred.wting the stability and control control-surface hinge-moment characteristics were preparedcharacteristics o.f an airplane. This material is based on by Mr. I. G. Recant and Mr. T. A. Toll, respectively, and thelecture notes.for a training couise .fo
38、r research workers engaged corresponding sections of the present report were basedupon the material prepared by these two members of thein airplane stability and control investigations. Langley Aeronautical Laboratory staff.INTRODUCTION A list of symbols is included as an appendix.In recent years, e
39、xtensive flight, wind-tunnel, and theo- LONGITUDINAL STABILITY AND CONTROLretieal investigations of the stability and control character- CHARACTERISTICS IN STRAIGHT FLIGHTistics of airplanes have led to an improved understanding ofthis subject and. to better correlation between the results of STABIL
40、ITYCHARACTERISTICSIN STRAIGHT.FLIGHTthese three research methods. The present report summa- REQUIREMENTSANDDEFINITIONSrizes the more important aspects of this field of research andpresents information that will aid the designers of an air- An airplane is required to be statically longitudinallyplane
41、 in selecting or modifying a configuration to provide stable with stick fixed or free in flight conditions in whichsatisfactory stabi.lity and control characteristics. The it is likely to be flown for long periods of time, and in thematerial given in this report is based on lecture notes for a landi
42、ng-approach and landing conditions. The meaningcourse, first given in 1942, that was intended to train re- of this requirement is explained in the following sections.search workers engaged in airplane stability and control First, the concept of trim and the concepts of static andinvestigations, dyna
43、mic stability are considered.The flying qualities of an airplane are defined as the An airplane is trimmed longitudinally in steady flight withstability and control characteristics that have an important stick fixed when it is in equilibrium, that is, when the re-bearing on the safety of flight and
44、on the pilots impressions sultant force on the airplane is zero and the pitching momentof the ease of flying an airplane in steady flight and in is zero. An airplane is trimmed in steady flight with stickmaneuvers. Most of the available knowledge of flying free when, in addition to the above conditi
45、ons, the stickqualities has been obtained from flight tests made by the force is zero. The methods of obtaining trim are to adjustNACA since 1939 on approximately 60 airplane-s of alltypes, the pitching moment to zero by means of the elevatorsIn these tests, recording instruments were used to obtain
46、 and to adjust the stick force to zero by either a trim tab, anquantitative measurements of control movements, control adjustable stabilizer, an auxiliary airfoil near the tail, or anforces, and airplane motions while the pilots performed cer- adjustable spring in the control system. Of these device
47、s,tain specified maneuvers. The results of many of these the trim tab is by far the most common.tests have been published as NACA Wartime Reports. In order to determine whether an airplane is stable, itReference 1 is a typical example of this type of report, first must be trimmed. Stability is relat
48、ed to _the behaviorFrom the fund of “information accumulated in these tests, of an airplane after it is disturbed slightly from the trimmedit has been possible to prepare a set of requirements for condition. Stability is referred to as stick-fixed or Stick-satisfactory handling qualities in terms of
49、 quantities that free stability, depending upon whether the control is heldmay be measured in flight or predicted from wind-tunnel fixed in its trim position after the disturbance or is left free.tests and theoretical analyses. When an airplane meets these The behavior of an airplane after such a disturbance mayrequirements, the airplane is fairly ce
