Download or read book Analysis and Correlation of Helicopter Rotor Blade Response in Variable Inflow Environment Ser 50405 written by K. D. Hilzinger and published by . This book was released on 1965 with total page 109 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Analysis and Correlation of Helicopter Rotor Blade Response in a Variable Inflow Environment written by Raymond G. Carlson and published by . This book was released on 1965 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt: The program was conducted to determine the ability to predict Helicopter rotor response with a combined analysis based on the Sikorsky aeroelastic analysis and the Cornell Aeronautical Laboratory variable inflow analysis. The Sikorsky analysis is a fully coupled flatwise-edgewise-torsional dynamic analysis modified to incorporate refinements in rotor trim and airload calculation and to adapt it for use with the variable inflow analysis. Analytical results were compared with available flight data for steady level flight of the H-34 at 41, 70, and 112 knots with a neutral center of gravity (C.G.), and 73 knots with aft C.G., as well as the HU-1A at 113 knots with neutral C.G. Fairly good correlation with test data was obtained. The analysis gave better correlation of blade air loads and bending moments than had been obtained from constant inflow analysis. In particular, more realistic values were obtained for the higher harmonic root-shear forces needed to define airframe response. While further improvement can be obtained by refinement of the variable inflow analysis, the combined analysis developed for the program provides an improved design tool for rotor blade evaluation. (Author).

Download or read book Technical Abstract Bulletin written by and published by . This book was released on with total page 684 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Monthly Catalog of United States Government Publications written by and published by . This book was released on 1965 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Investigation of Helicopter Control Loads Induced by Stall Flutter written by P. J. Arcidiacono and published by . This book was released on 1970 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: An analytical study was conducted to determine if available unsteady normal force and moment aerodynamic test data could be used in conjunction with existing helicopter rotor aeroelastic and variable inflow analyses to provide a method for predicting the stall flutter response of a helicopter rotor blade. For this purpose, incompressible unsteady aerodynamic data for an NACA 0012 airfoil executing pure sinusoidal pitching motions were employed. To apply such data under rotor blade operating conditions where multiharmonic motions and velocity variations exist, the data were expressed as functions of instantaneous section angle of attack, angular velocity, and angular acceleration. In addition, scaling procedures were developed in an attempt to account for the effects of compressibility. Limited application of the resulting analysis to define the aeroelastic characteristics of several blade designs showed that significant self-excited torsional oscillations of the stall flutter type could, in fact, be predicted for certain combinations of flight conditions and blade designs. Correlation studies, to evaluate the ability of the analysis to predict control loads, were performed with CH-53A maneuvering flight test data and with level flight test data from the NH-3A (S-61F). (Author).

Download or read book U S Government Research and Development Reports written by and published by . This book was released on 1965 with total page 616 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Influence of Dynamic Inflow on the Helicopter Vertical Response written by and published by . This book was released on 1986 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Investigation of Helicopter Control Loads Induced by Stall Flutter written by Peter J. Arcidiacono and published by . This book was released on 1970 with total page 179 pages. Available in PDF, EPUB and Kindle. Book excerpt: An analytical study was conducted to determine if available unsteady normal force and moment aerodynamic test data could be used in conjunction with existing helicopter rotor aeroelastic and variable inflow analyses to provide a method for predicting the stall flutter response of a helicopter rotor blade. For this purpose, incompressible unsteady aerodynamic data for an NACA 0012 airfoil executing pure sinusoidal pitching motions were employed. To apply such data under rotor blade operating conditions where multiharmonic motions and velocity variations exist, the data were expressed as functions of instantaneous section angle of attack, angular velocity, and angular acceleration. In addition, scaling procedures were developed in an attempt to account for the effects of compressibility. Limited application of the resulting analysis to define the aeroelastic characteristics of several blade designs showed that significant self-excited torsional oscillations of the stall flutter type could, in fact, be predicted for certain combinations of flight conditions and blade designs. Correlation studies, to evaluate the ability of the analysis to predict control loads, were performed with CH-53A maneuvering flight test data and with level flight test data from the NH-3A (S-61F). (Author).

Download or read book Aeorelastic analysis for helicopter rotor blades with time variable nonlinear structural twist and multiple structural redundancy mathematical derivation and program user s manual written by Richard L. Bielawa and published by . This book was released on 1976 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Calculation of Flight Vibration Levels of the AH 1G Helicopter and Correlation with Existing Flight Vibration Measurements written by and published by . This book was released on 1990 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Government Reports Announcements written by and published by . This book was released on 1965 with total page 1170 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book U S Government Research Development Reports written by and published by . This book was released on 1965-12 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Government Reports Announcements Index written by and published by . This book was released on 1965 with total page 914 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Analytical Investigation of the Effects of Blade Flexibility Unsteady Aerodynamics and Variable Inflow on Helicopter Rotor Stall Characteristics written by E. D. Bellnger and published by . This book was released on 1971 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Bibliography of Scientific and Industrial Reports written by and published by . This book was released on 1965-11 with total page 1246 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book NASA SP written by and published by . This book was released on 1962 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Radius of Action of Aircraft written by Mary Tornich and published by . This book was released on 1940 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: