Download or read book Flight Test Evaluation of Techniques to Predict Longitudinal Pilot Induced Oscillations written by Eileen A. Bjorkman and published by . This book was released on 1986 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this study was to determine if pilot induced oscillations (PIOs) can be predicted prior to flight using existing PIO prediction techniques. Two techniques to predict longitudinal PIO tendencies (Ralph Smith's theory and Roger Hoh's bandwidth method) were studied analytically using an existing PIO data base. Suggestions were made for both techniques to allow prediction of PIO rating. The two techniques were then applied to 18 aircraft/flight control system landing configuration. The 18 configurations were flight tested using a flared landing task with the USAF/Calspan variable stability NT-33A. Smith's theory correctly prediction the PIO tendencies and frequencies provided the configuration was not sensitive to the pilot model used. A suggested modification to Smith's theory correctly predicted PIO ratings within an average of 0.6 rating. A suggested modification to Hoh's bandwidth method predicted PIO ratings within an average of 0.5 rating. The limited data base was too small to draw any definite conclusions. Recommendations for further study included collecting more PIO data and using existing data bases and simulator studies to better define the two techniques and to gain physical insights into PIO mechanization. (Theses).
Download or read book Analysis of Longitudinal Pilot induced Oscillation Tendencies of YF 12 Aircraft written by Flight Research Center (U.S.) and published by . This book was released on 1975 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Flight Test Evaluation of Techniques to Predict Longitudinal Pilot Induced Oscillations written by Eileen A. Bjorkman (CAPT, USAF.) and published by . This book was released on 1986 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Prediction of Longitudinal Pilot Induced Oscillations Using the Optimal Control Model written by Steven W. Lindsey and published by . This book was released on 1989 with total page 194 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis evaluates the OCM in predicting handling qualities and PIO pilot ratings during the approach and landing task. Using two existing PIO databases, analytical prediction schemes were developed using the OCM. The prediction schemes used were flight path error and crossover frequency. The prediction schemes were applied to 12 different aircraft/flight control system landing configurations. The 12 configurations were flight tested using a USAF/Calspan variable stability NT-33A. The OCM was able to predict pilot handling qualities ratings (PHQR) accurately (within one pilot rating) 80% of the time. PIO ratings were accurately predicted 96% of the time. Due to a PIO rating problem in the original databases, the PIO prediction schemes were modified using flight test data. Additional flight test configurations should be flown to verify the revised flight path error and crossover frequency prediction schemes. Because of the subjective nature of PHQRs and PIO ratings, the flight test results varied between pilots. The correlation between multiengine pilots was better than with the fighter pilot. The crossover frequency prediction scheme was the most accurate predictor of pilot ratings, while the flight path error prediction scheme was slightly more accurate for PIO ratings. Both predictors agreed with classical control theory, showing correlation between flight path error, crossover frequency, and pilot/PIO ratings. The flight path error and crossover frequency rating prediction methods should be used as a tool in flight control system design. Variable stability aircraft; Flying qualities. (edc).
Download or read book Preliminary Flight Evaluation of the Stability and Control Derivatives and Dynamic Characteristics of the Unaugmented XB 70 1 Airplane Including Comparisons with Predictions written by and published by . This book was released on 1968 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Flight Testing Techniques for the Evaluation of Light Aircraft Stability Derivitives written by Frederick O. Smetana and published by . This book was released on 1972 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Pilot Induced Oscillation Research The Status at the End of the Century written by and published by . This book was released on 2001 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Stability and Control written by Courtland D. Perkins and published by Elsevier. This book was released on 2014-05-12 with total page 520 pages. Available in PDF, EPUB and Kindle. Book excerpt: Flight Testing, Volume II: Stability and Control focuses on the development of adequate flight test techniques for the appraisal of stability and control characteristics and flying qualities of airplanes. This book discusses the flying quality requirements, longitudinal motions, and flight determination of stick-fixed neutral points. The determination of aerodynamic parameters from steady maneuvering, desirable control characteristics in steady flight, and various forms of lateral control surfaces are also elaborated. This publication likewise covers the measurement of maximum lift coefficient, emergency anti-spin devices, and concept of the altitude-Mach number flight envelope. This volume is recommended for design, development or research engineers, test pilots, and instrumentation personnel interested in airplane stability and control.
Download or read book Influence of Display and Control Compatibility on Pilot induced Oscillations written by Marvin C. Waller and published by . This book was released on 1981 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Analysis of a Coupled Roll spiral mode Pilot induced Oscillation Experienced with the M2 F2 Lifting Body written by Robert W. Kempel and published by . This book was released on 1971 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the 16 glide flights of the M2 -F2 lifting body vehicle, severe lateral pilot-induced oscillations occurred on three occasions in the low - angle of -attack, final-approach, preflare situation. These oscillations were analyzed qualitatively to determine the type and similarity and by a systems analysis to determine the root cause. The analysis was complemented by a piloted simulator study, which verified the results. The systems analysis revealed the presence of a coupled roll-spiral mode which caused the pilots to generate a closed-loop lateral instability in the low-angle -of -attack, preflare flight region. A systems analysis, a piloted simulator study, and flight data showed that the addition of a fixed center fin lessened the pilot-induced-oscillation tendencies in the critical flight region.
Download or read book A Limited Flight Test Investigation of Pilot Induced Oscillation Due to Elevator Rate Limiting HAVE LIMITS written by and published by . This book was released on 1997 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The report presents the results of a limited flight test investigation of pilot-induced oscillation (PIO) due to elevator rate limiting. The objective of this effort was to gather in-flight and ground-based simulation data on longitudinal PIO tendecies due to elevator rate limiting. Preliminary, ground-based simulation was conducted at the USAF Test Pilot School (TPS) from 1 March to 9 April 1997. Nine sorties, totaling 12.8 flight hours, were flown in the NT-33A aircraft. Additional ground-based simulation was conducted at the Flight Dynamics Directorate, Wright-Patterson AFB, Ohio, on 25 April 1997. The USAF TPS was the responsible test organization.
Download or read book Development and Evaluation of a Performance Modeling Flight Test Approach Based on Quasi Steady state Maneuvers written by and published by . This book was released on 1984 with total page 430 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Influence of Display and Control Compatibility on Pilot induced Oscillations written by Marvin C. Waller and published by . This book was released on 1981 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Flight Investigation of Longitudinal Short Period Frequency Requirements and Pio Tendencies written by Dante A. DiFranco and published by . This book was released on 1967 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt: The results of a flight test program to investigate longitudinal short period frequency requirements and PIO (pilot-induced oscillation) tendencies are presented and discussed. Short period frequency requirements were investigated with a damping ratio of approximately 0.7 at three fixed values. PIO tendencies were investigated with various values. The feel system dynamic characteristics were held essentially constant throughout the program. A variable stability T-33 airplane was used as an in-flight simulator. Each configuration was evaluated as a fighter in 'up and away' flight. The evaluation pilots commented on each configuration and rated each numerically. An analysis of pilot ratings and pilot comments was made, and these in turn were related to various handling qualities parameters. In the analysis and interpretation of the handling qualities results, feel system dynamics and pilot-selected stick force gradients were also important considerations. (Author).
Download or read book Identifying the Pilot in Pilot induced Oscillations written by David G. Mitchell and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Theory for Longitudinal Short Period Pilot Induced Oscillations written by Ralph H. Smith and published by . This book was released on 1977 with total page 141 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report presents a theory for longitudinal, short-period, pilot-induced oscillations (PIO). The theory explains how the airplane's pitch attitude and normal acceleration modes can couple with pilot dynamics to produce large-amplitude, uncontrollable oscillations. The effects of control system dynamics and feel system nonlinearities are encompassed by this theory. It is concluded that an airplane's potential for PIO can be determined based entirely on linear systems analysis; the prediction of fully-developed PIO frequency and amplitude requires that all significant nonlinearities be considered. The theory postulates that PIO can develop either as a result of closed loop control of pitch attitude or from abrupt control or atmospheric inputs of size sufficient to excite a lightly damped, dominant, stick-free airplane mode. A number of PIO case histories are examined; it is shown that these confirm the proposed theory. The implications of the theory to flight test and to simulation are discussed. A generalized definition for PIO is given which permits distinctions to be made between pilot-vehicle system oscillations due only to attitude control and those due to attitude plus path control modes. It is suggested that the theory can be easily extended to the study of lateral-directional PIO. A bibliography of PIO source material is included with this report. (Author).
Download or read book Prediction of Longitudinal Pilot Induced Oscillations Using the Optimal Control Model written by Steven W. Lindsey (CAPT, USAF.) and published by . This book was released on 1990 with total page 382 pages. Available in PDF, EPUB and Kindle. Book excerpt:
