PILOT RATING TECHNIQUES FOR THE ESTIMATION AND EVALUATION OF HANDLING QUALITIES

Abstract : Although rating scales of varied forms have been widely used to estimate and evaluate handling qualities over the past decade, a number of deficiencies in both method and data base have been apparent. The investigation was aimed at overcoming many of these deficiencies by attempting to resolve the difficulties experienced with rating scales themselves, and by extending and adding to already existing relationships between ratings and pilot/vehicle system parameters. Rating scales have come under increasing criticism for problems such as wording ambiguity, the dual mission character of some scales, the nonuniformity in the distribution of descriptors across the scale, and the misuse of scales which has occurred when ratings have been averaged. Psychometric methods provide an approach to these problems, and were used to scale several phrases descriptive of vehicle handling qualities. Thus, quantitative characteristics were derived for contemporary scales through the use of the Method of Successive Intervals. An experiment was conducted which added to available data relating Cooper ratings and pilot/vehicle parameters, and which also tested some potential alternate scale candidates. The correlation results indicate that ratings are probably based on performance and the degree of difficulty experienced in maintaining the performance. The difficulty is most easily represented by the pilot equalization required and the vehicle stick characteristics.