Download or read book V STOL Dynamics and Aeroelastic Rotor Airframe Technology Volume I State of the Art Review of V STOL Rotor Technology written by H. R. Alexander and published by . This book was released on 1973 with total page 133 pages. Available in PDF, EPUB and Kindle. Book excerpt: The aeroelastic phenomena associated with prop/rotor systems are discussed and classified. It is concluded that an acceptable technology exists in several areas, including wing/rotor divergence, whirl flutter, aeromechanical instability, and air and ground resonance. The technology is less successful in those areas where the flow through the rotor is significantly nonaxial, e.g., tilt-rotor transition regime and high-speed helicopter flight; also when forms of intermodal blade coupling exist due to finite deflections of the blades. It is believed that, in addition to collective deflections, finite cyclical deflections of the blades produce destabilizing coupling effects in some cases. Significantly large edgewise flow in combination with nonzero blade steady-state deflections is also seen to be destabilizing. A minimum-complexity methodology which may be expected to correlate with currently identified phenomena is defined. (Author).
Download or read book V STOL Dynamics and Aeroelastic Rotor Airframe Technology Volume 2 Description and Correlation of New Methodologies written by and published by . This book was released on 1972 with total page 323 pages. Available in PDF, EPUB and Kindle. Book excerpt: The blade loads analysis calculates rotor blade flapwise, chordwise, and torsional deflections and loads, together with rotor performance, control system forces, and vibratory hub loads. Articulated and hingeless rotors with 2 to 9 blades and large twist may be analyzed. The analysis considers coupled flapwise-chordwise-torsion deflections of the rotor blades. Boundary conditions for either articulated or hingeless rotors are applied and the solution is obtained by expanding the variables in a 10-harmonic Fourier series. Airload calculations include the effects of airfoil section geometry, compressibility, stall, 3-dimensional flow, unsteady aerodynamics, and nonuniform inflow. In the area of rotor loads, correlation of prop/rotor and helicopter rotor loads test data has been made with the fully coupled rotor loads and steady in-plane hub moments for prop/rotors and for alternating blade loads, pitch link loads, and airloads for helicopters. An unexpected discovery of this study was the sensitivity of the rotor derivatives to blade lead-lag motion when the frequency of this mode is near 1 per rev. This result was subsequently confirmed by test. The impact of the new prediction capabilities and possible refinement or development of design criteria through use of the analysis are discussed. The methods contained in this report are intended to be used by designers to calculate with improved accuracy, the dynamic and aeroelastic response characteristics of rotor powered V/STOL aircraft. The essential new feature of these methods is that the coupled flap-pitch-lag blade deflections are taken into account. These calculations are essential if a high level of confidence is to be had in the results.
Download or read book NASA Technical Paper written by and published by . This book was released on 1977 with total page 780 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book V STOL Dynamics and Aeroelastic Rotor Airframe Technology Volume III User s Manuals Computer Programs for Aeroelastic Stability Analysis and Aeroelastic Prop Rotor Loads Analysis written by A. K. Amos and published by . This book was released on 1972 with total page 263 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report provides user's instructions for two computer programs for aeroelastic stability analysis and for aeroelastic prop/rotor loads analysis. Each program is carefully described and explained, symbols and sign conventions are identified, and input and output data are presented. A sample program run for each analysis is then given. In addition, sample programs for some subroutines are provided. Notes and suggestions on program usage are presented. The methods contained in this report are intended to be used by designers to calculate with improved accuracy, the dynamic and aeroelastic response characteristics of rotor powered V/STOL aircraft. The essential new feature of these methods is that the coupled flap-pitch-lag blade deflections are taken into account. These calculations are essential if a high level of confidence is to be had in the results.
Download or read book Technical Abstract Bulletin written by and published by . This book was released on 1980 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book V Stol Dynamics and Aeroelastic Rotor Airframe Technology written by H. R. Alexander and published by . This book was released on 1973 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Whirl Flutter of Turboprop Aircraft Structures written by Jiří Čečrdle and published by Elsevier. This book was released on 2023-01-13 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt: Whirl Flutter of Turboprop Aircraft Structures, Second Edition explores the whirl flutter phenomenon, including theoretical, practical, analytical and experimental aspects of the matter. Sections provide a general overview regarding aeroelasticity, discussions on the physical principle and the occurrence of whirl flutter in aerospace practice, and experimental research conducted, especially from the 60s. Other chapters delve into analytical methods such as basic and advanced linear models, non-linear and CFD based methods, certification issues including regulation requirements, a description of possible certification approaches, and several examples of aircraft certification from aerospace. Finally, a database of relevant books, reports and papers is provided. This updated and expanded second edition covers new chapters including both analytical and experimental aspects of the subject matter. - Provides complex information on turboprop aircraft whirl flutter phenomenon - Presents both theoretical and practical (certification related) issues - Includes experimental research as well as analytical models (basic and advanced) of matter - Includes both early-performed works and recent developments - Contains a listing of relevant books and reports
Download or read book An Experimental and Analytical Investigation of Proprotor Whirl Flutter written by Raymond G. Kvaternik and published by . This book was released on 1977 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Journal of the American Helicopter Society written by American Helicopter Society and published by . This book was released on 2002 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Hingeless Rotorcraft Flight Dynamics written by Kurt H. Hohenemser and published by . This book was released on 1974 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: The state of hingless rotorcraft research and development in the NATO countries as of 1973 is described. The scope of this report is limited to flight dynamics (as defined in the Preface) since most of the hingeless rotorcraft problems have occurred in this area. In the Introduction, the special place of the hingeless rotorcraft within the family of rotorcraft is considered. The chapter on the history of hingeless rotorcraft describes the hingeless rotor research and development of the various rotorcraft manufacturers and the hingless rotor research at government laboratories and universities. A hierarchy of dynamic concepts from isolated blade dynamics to complete rotor/body dynamics is introduced. The effects of the basic rotor design parameters on flight dynamics are traced and certain hingeless rotorcraft problems are treated in some detail. A special chapter is devoted to the alleviation of hingeless rotor flight-dynamics problems by feedback control systems. Finaly, analytical modeling techniques, mathematical analysis techniques, and model and flight testing techniques for hingeless rotorcraft are discussed.
Download or read book Dynamics Control and Flying Qualities of V STOL Aircraft written by James A. Franklin and published by AIAA. This book was released on 2002 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt: Annotation This text presents the principles of dynamics and control for vertical, short take-off landing (V/STOL) aircraft. It is the first book of its kind. It is intended for graduate students and professionals in aeronautics who have knowledge of linear systems analysis, aircraft static, dynamic stability, and control. The text begins with a discussion of V/STOL aircraft operations. Control strategies, equations of motion, longitudinal and lateral-directional flying qualities in both hover and forward flight, wind and turbulence responses, and control augmentation and cockpit displays are covered. Specific examples of the YAV-8B Harrier and XV-15 Tilt Rotor aircraft are used to illustrate actual V/STOL dynamic and control characteristics.
Download or read book Aerodynamics of V STOL Flight written by Barnes Warnock McCormick and published by Courier Corporation. This book was released on 1999-01-01 with total page 356 pages. Available in PDF, EPUB and Kindle. Book excerpt: An extremely practical overview of V/STOL (vertical/short takeoff and landing) aerodynamics, this volume offers a presentation of general theoretical and applied aerodynamic principles, covering propeller and helicopter rotor theory for both the static and forward flight cases. Both a text for students and a reference for professionals, the book can be used for advanced undergraduate or graduate courses. Numerous detailed figures, plus exercises. 1967 edition. Preface. Appendix. Index.
Download or read book Recent Progress in V STOL Aircraft Technology written by and published by . This book was released on 1981 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Annual Index written by and published by . This book was released on 1981 with total page 942 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sections 1-2. Keyword Index.--Section 3. Personal author index.--Section 4. Corporate author index.-- Section 5. Contract/grant number index, NTIS order/report number index 1-E.--Section 6. NTIS order/report number index F-Z.
Download or read book Review of Basic Principles of V STOL Aerodynamics written by Richard E. Kuhn and published by . This book was released on 1961 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1991 with total page 1460 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Download or read book Comprehensive Helicopter Analysis A State of the Art Review written by and published by . This book was released on 1978 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt:
