1、NASA TECHNICAL|k.-ZNOTE NASA TN D-5153CASECOPF7 LETHE USE OF PILOT RATINGIN THE EVALUATION OFAIRCRAFT HANDLING QUALITIESGeorge E. CooperAmes Research CenterandRobert P. Harper, Jr.Cornell Aeronautical LaboratoryNATIONAL AERONAUTICS AND SPACE ADMINISTRATION WASHINGTON, D. C. APRIL 1969Provided by IHS
2、Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NASA TN D-5153THE USE OF PILOT RATING IN THE EVALUATION OFAIRCRAFT HANDLING QUALITIESBy George E. CooperAmes Research C
3、enterMoffett Field, Calif.andRobert P. Harper, Jr.Cornell Aeronautical LaboratoryBuffalo, N.Y.NATIONAL AERONAUTICS AND SPACE ADMINISTRATIONFor sale by the Clearinghouse for Federal Scientific and Technical InformationSpringfield, Virginia 22151 - CFSTI price $3.00Provided by IHSNot for ResaleNo repr
4、oduction or networking permitted without license from IHS-,-,-Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-TIlE USE OF PILOT RATING IN THE EVALUNIION OFAIRCRAFT HANDLING QUALITIESBy George E. CooperAmes Research CenterandRobert P. Harper, Jr.Corne
5、ll Aeronautical LaboratorySUb_v_kRYPilot rating scales and their use in assessing aircraft handlingqualities are reviewed historically, and objections that have been raised tolimitations of earlier scales are considered in the development of a revisedscale. Terminology used in the evaluation of hand
6、ling qualities is reviewedand new definitions are proposed to improve communication and internationalunderstanding. Of particular significance is the new definition of handlingqualities, which emphasizes the importance of factors that influence the selec-tion of a rating other than stability and con
7、trol characteristics.The experimental use of pilot rating is discussed in detail, with specialattention devoted to (i) clarifying the difference between mission and task,(2) identifying what the rating applies to, (3) considering the pilotsassessment criteria, and (4) defining the simulation situati
8、on. The importantelements of the report are then summarized in a suggested “Briefing Guide,“designed for guidance in planning and executing handling qualitiesexperiments.INTRODUCTIONThe widespread application of pilot rating scales in the evaluation ofaircraft handling qualities has confirmed their
9、basic utility, but has, at thesame time, exposed some weaknesses of the scales as originally proposed. Itwas therefore considered desirable to re-examine existing rating scales withthe purpose of developing a single improved scale and of clarifying its use inthe evaluation of handling qualities. In
10、response to an invitation from theFlight Mechanics Panel, AGARD, a paper entitled, “A Revised Pilot Rating Scalefor the Evaluation of Handling Qualities,“ was prepared and presented at theSeptember 1966 meeting (ref. i). A longer version of this paper (ref. 2) con-tains some additional explanatory d
11、iscussion of the use of pilot rating scales.Additional constructive criticism was then based on experience gained withthis revised scale.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-In general, the revised scale was preferred over earlier scales,
12、butconstructive criticism from manyresearch and development groups alsoindicated the need for additional changes or clarifying discussion. Diffi-culties, for example, were experienced with the semantics in that certainwords had rather different connotations in the United States, England, and inFranc
13、e. The purpose of this report, then, is to clarify and modify, as appro-priate, the material presented in references 1 and 2. Oneof the first objec-tives of the present report is to define precisely the basic terminology andexplain the new features in the scale. The report goes on to discuss the mor
14、eimportant factors that are considered by the pilot in the selection of a rat-ing or that will otherwise influence the rating. Throughout the discussion,attention is directed to the questions: (i) what is the pilot being asked torate?, and (2) how will the experimental results be used? The answers t
15、o bothquestions have important bearing on the interpretation of evaluations madebypilots with different backgrounds, experience, and points of view. The finalsection of the discussion is devoted to a review of certain other consider-ations that are helpful in the design of handling qualities experim
16、ents and tothe use of pilot rating. The important elements of the report are summarizedin a condensed“Briefing Guide“ for use in planning and executing handlingqualities experiments.DISCUSSIONOF HANDLINGQUALITIESClarification of TermsFor a pilot rating scale to be universally acceptable and consiste
17、ntlyapplied in the evaluation of handling qualities, the terminology must beeasily understood by all persons working in the field. Those terms requiringspecific attention are defined in appendix A, and several definitions are sug-gested that mayhelp clarify and standardize the terminology. Someof th
18、eterms suggested in reference 3 have been adopted in this report. Those mostsignificant to a discussion of handling qualities are examined in considerabledetail in the following paragraphs. Others are discussed as the need arises.Handling qualities.- The term “Handling Qualities“ requires a cleardef
19、inition in order to emphasize that it includes more than just stability andcontrol characteristics. Other factors that influence the handling qualitiesare the cockpit interface (e.g., displays, controls), the aircraft environ-ment (e.g., weather conditions, visibility, turbulence) and stress, theeff
20、ects of which cannot readily be segregated. Thus in most tests, handlingqualities are really being evaluated in the aggregate.In appendix A, “Handling Qualities“ is defined as “those qualities orcharacteristics of an aircraft that govern the ease and precision with whicha pilot is able to perform th
21、e tasks required in support of an aircraft role.“The generally accepted meaning of “Flying Qualities“ is similar to this defi-nition of “Handling Qualities,“ so only the latter term is used in thisreport.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-
22、,-Figure 1 illustrates the factors besides stability and control thatinfluence handling qualities. Here the primary elements of the pilot controlloop are arranged to illustrate their relationship to the operation of thepilot-vehicle combination. In addition to the pilot, the task, and thestability a
23、nd control characteristics, factors shownas influencing closure ofthe pilot control loops are the cockpit interface, the aircraft environment,and the pilots stress.HandlingqualitiesfactorsPilotcontrolloopsTaskt!TaskControl taskAuxiliarytasksI I I stobi,ity ICockpit AircraflI Pilot J interface J and
24、control I environmentcharacler islicsI I 1 II I,v,sua,nfoExterna I !Instruments JKinesthetlCinfo i JMotion cues ID_sturbances l._ PrincipalcontrolsFPi lot I I lcharacteristics ,ress ,., o,ectors tE_straction lSu_rprise from r I Normal ordisturbance j failure)or f_IEures J, ConfigurationWeRght, Massd
25、istributionstateDynamics offailureTaskperformance-IAircraft j_ Taskmovement performanceEnvironmenta IstateDay/NightweatherTurbulenceWind shearVislbdttyCrosswindetc,Altitude/speed, etcFigure i.- Elements of control loop that influence handling qualities.Mission.- The term “mission“ has been used in t
26、he United States ratherloosely, and may actually have several meanings, depending on how it is used.“Mission“ has been used to identify, in a general sense, the purpose orobjective for which an aircraft is built. It has also been used to designatea complete flight or sortie or even an undefined part
27、 of the flight. Byinference, this undefined part is usually the special flight phase duringwhich the primary assignment is carried out.To avoid this ambiguity, the terms “role,“ “flight“ or “sortie,“ “flightphase,“ and “flight subphase“ are defined for use in place of “mission“ (ormission element).
28、The continued use of “mission“ in relation to handlingqualities, however, makes it worthwhile to have an acceptable definition.One that has been suggested (ref. 4) is “the composite of pilot-vehicle func-tions that must be performed to fulfill operational requirements.“ In thepresent report, “missio
29、n“ is a general term used to convey this concept of“operational requirements,“ that is, the objectives or delineation of what itProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-is that the pilot-vehicle combination must be able to accomplish. As a rul
30、e,the mission objectives (required operations) are cited in more detail as theflight segment (flight phase or subphase) of interest becomesmore specific.The distinct differences intended between “mission“ and “task“ will beclarified in the following paragraphs.Task.- The term “task“ also has various
31、 connotations. We are concernedhere only with the pilots task, which includes controlling the aircraft aswell as associated functions, not directly related to controlling the aircraft,such as navigation and communications. A task in the sense that it is used inhandling qualities evaluations is defin
32、ed as “the actual work assigned a pilotto be performed in completion of, or as representative of, a designated flightsegment.“ In being representative of a flight phase, for example, the impor-tant pilot-vehicle functions required to fulfill the operational requirementsfor that flight phase would be
33、 represented in the task. Use of “task“ and“mission“ differs then, in that a task represents what the pilot is actuallyasked to do (as in a simulation task) while a mission refers to all opera-tional requirements the pilot-vehicle combination must be able to accomplishif the “intended use“ of the ai
34、rcraft is to be fulfilled.It is convenient to consider the complete task to be composed of (I) thecontrol task, and (2) auxiliary tasks. The control task requires actuationof the principal controls and the selectors as required. The auxiliary tasksinvolve the pilot in actions other than direct contr
35、ol of the aircraft.Fli_ht phase.- The terms “flight,“ “flight phase,“ and “flight subphase“denote the flight profile of an aircraft and its subdivision into convenientsegments. The delineation of aircraft role and the division of a completeflight into discrete segments for more definitive examinatio
36、n is illustratedin figure 2. Representative examples of what is meant by aircraft role, com-plete flight, flight phase, and subphase are given in this figure as well asin appendix A. A subphase is defined as “that part of a flight phase havinga single objective, and a single configuration or change
37、in configuration.“A subphase evaluation then would provide a direct correlation between aspecific set of stability and control parameters and pilot rating.In summary then, the role of an aircraft defines its intended use onlyin a general sense. The mission delineates this use in terms of specificobj
38、ectives, that is, the required operations of the pilot-vehicle combination.The task delineates those aspects of the mission that are work assigned to thepilot.Methods of Determining Aircraft Handling QualitiesThe relationship between stability and control parameters and the degreeof suitability of t
39、he airplane for the mission may be examined by:Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-FLIGHT IGround/deckFLIGHTPHASESROLE I The funchon which defines the intended use of lhe a_rcraftTakeoff Climb CruiseASpecialphasedeterminedby roleDescent A
40、pproach LondingSUBPHASES(TYPICAL)TASKTaxiing,(grourld orwater)CatapultpOSlhOn_ngConfmed areaposit IoniNgAccel - V Iv, - vRvR-VLOAbortedtakeoffI st Segment2 nd SegmentOther segments as requiredVOR tracMngE nroute climbAltitudehoidingAltitudechangeA ir - airtrackingDivebombingLow levelbombingRefueling
41、The actual work assigned Q pilot which is Io be performed _n designated fhght phasesE nroutedescentEmergencydescenlTerminalarea holdLocolizerCaplureGlide pathcaptureLStrackingWave offFlare tolouchdown0 ffsetcorrectionCrosswlndlandmgGrounddecelerationFigure 2.- The relationship between role, flight s
42、egments, and task.:!I. Theoretical analysis2. Experimental performance measurementa. Pilot iffputb. Pilot-vehicle output3. Pilot evaluationEach approach has an important part in the complete evaluation. Onemight ask, however, “Why is the pilot assessment necessary?“ The answer mustconsider the two a
43、lternatives, theoretical analysis and performance measure-ment. At present, the applicability of the mathematical analysis includingrepresentation of the human operator is restricted to the analysis of speci-fic simple tasks. Since the intended use (mission) is made up of severaltasks and several mo
44、des of pilot-vehicle behavior, it is difficult first todescribe accurately all modes analytically, and, second to integrate the qual-ity in the separate tasks into a measure of overall quality for the intendeduse. Theoretical analysis is fundamental to the analytical prediction ofhandling qualities,
45、 but cannot adequately treat the complex interactions thatare now investigated by means of experimental pilot evaluation.The attainment of satisfactory performance in fulfilling a designatedmission is, of course, a fundamental reason for our concern with handling qual-ities. Why, then, cannot the ex
46、perimental measurement of performance replacepilot evaluation? Why not measure pilot-vehicle output performance in theintended use? Isnt good performance consonant with good quality? Unfortu-nately, the answer to the latter question is “not always.“5Provided by IHSNot for ResaleNo reproduction or ne
47、tworking permitted without license from IHS-,-,-A significant difficulty arises here in that, first, the tasks selectedfor measuring performance may not demand of the pilot all that the real mis-sion demands, especially in terms of distractions, auxiliary tasks, and pilotstress. In the second place,
48、 pilot performance must also be measured andinterpreted so that the pilot-vehicle performance can be evaluated correctly.The pilot is an adaptive controller whose goal (when he is so instructed) isto achieve good performance. In a specific task, he is capable of attain-ing essentially the same perfo
49、rmance for a wide range of vehicle characteris-tics, at the expense of significant reductions in his capacity to assume otherduties and to plan subsequent operations. Significant differences in his taskperformance may not be measured when very real differences in mission suit-ability do exist. The pilots performanc
