Aeroelastic problems of Rotorcraft

In this chapter we will examine a number of aeroelastic phenomena associated with helicopters and other rotor or propeller driven aircraft. Certain areas have been selected for treatment to illustrate some significant stability problems which are associated with the design of helicopters. The approach to be followed employs simplified modelling of various problems such that physical insight into the nature of the phenomena can be obtained. In general a complete and precise formulation of many of the problem areas discussed is highly complex and the reader is referred to the literature for these more detailed formulations.

[1]  L. Goland,et al.  Dynamic Effects in Rotor Blade Bending , 1951 .

[2]  M. I. Young.  A Simplified Theory of Hingeless Rotors with Application to Tandem Helicopters , 1962 .

[3]  Richard K. Fisher,et al.  Rotor High Speed Performance, Theory vs. Test , 1970 .

[4]  Jaan Liiva,et al.  Dynamic Stall Of Airfoil Sections For High-Speed Rotors , 1969 .

[5]  Pei Chi Chou,et al.  Pitch-Lag Instability of Helicopter Rotors , 1958 .

[6]  R. A. Ormiston,et al.  A Study of Stall-Induced Flap-Lag Instability of Hingeless Rotors , 1973 .

[7]  Robert P. Coleman,et al.  Theory of self-excited mechanical oscillations of helicopter rotors with hinged blades , 1958 .

[8]  N. D. Ham,et al.  On the mechanism of dynamic stall. , 1972 .

[9]  R. A. Ormiston,et al.  Aeromechanical stability of soft inplane hingeless rotor helicopters , 1977 .

[10]  D. E. Cooper,et al.  Flight investigation of rotor/vehicle state feedback , 1975 .

[11]  R. E. Donham,et al.  Ground and air resonance characteristics of a soft in-plane rigid-rotor system , 1969 .

[12]  Robert M. Bennett,et al.  AN EXPERIMENTAL INVESTIGATION OF HELICOPTER STABILITY CHARACTERISTICS NEAR HOVERING FLIGHT USING A DYNAMICALLY SIMILAR MODEL , 1960 .

[13]  W. Earl Hall,et al.  Prop‐Rotor Stability at High Advance Ratios , 1966 .

[14]  W. J. McCroskey,et al.  Detailed aerodynamic measurements on a model rotor in the blade stall regime , 1971 .

[15]  Earl H. Dowell,et al.  Nonlinear equations of motion for the elastic bending and torsion of twisted nonuniform rotor blades , 1974 .

[16]  Norman D Ham,et al.  Helicopter Blade Flutter , 1973 .

[17]  R. T. Yntema,et al.  Simplified Procedures and Charts for the Rapid Estimation of Bending Frequencies of Rotating Beams , 1954 .

[18]  R. E. Hansford,et al.  Torsion-Flap-Lag Coupling on Helicopter Rotor Blades , 1973 .

[19]  Robert G. Loewy,et al.  Review of rotary-wing V/STOL dynamic and aeroelastic problems , 1969 .

[20]  David A. Peters,et al.  Application of the Floquet Transition Matrix to Problems of Lifting Rotor Stability , 1971 .

[21]  H. C. Curtiss.  Sensitivity of Hingeless Rotor Blade Flap-lag Stability in Hover to Analytical Modelling Assumptions , 1975 .

[22]  Leonard Goland,et al.  A Comparison of the Calculated and Observed Flutter Characteristics of a Helicopter Rotor Blade , 1957 .

[23]  K H Hohenemser.  Hingeless Rotorcraft Flight Dynamics , 1974 .

[24]  Norimichi Kawakami,et al.  Dynamics of an elastic seesaw rotor , 1977 .

[25]  Peretz P. Friedmann,et al.  Recent developments in rotary-wing aeroelasticity , 1977 .

[26]  H. C. Curtiss,et al.  Complex Coordinates in Near Hovering Rotor Dynamics , 1973 .

[27]  Peretz Friedmann,et al.  Aeroelastic Stability Of Complete Rotors With Application To A Teetering Rotor In Forward Flight , 1976 .

[28]  Kurt H. Hohenemser,et al.  Some Applications of the Method of Multiblade Coordinates , 1972 .

[29]  Alfred Gessow,et al.  Aerodynamics of the Helicopter , 1981 .

[30]  R. T. Lytwyn,et al.  The Influence of Blade Flapping Restraint on the Dynamic Stability of Low Disk Loading Propeller-Rotors , 1967 .

[31]  H. C. Curtiss,et al.  An experimental investigation of the flap-lag stability of a hingeless rotor with comparable levels of hub and blade stiffness in hovering flight , 1976 .

[32]  J. E. Burkam,et al.  Exploration of Aeroelastic Stability Boundaries with a Soft-in-Plane Hingeless-Rotor Model , 1972 .

[33]  Boeing,et al.  Airborne and Ground Resonance of Hingeless Rotors , 1971 .

[34]  L. Ericsson,et al.  Dynamic Stall of Helicopter Blades , 1970 .

[35]  Dewey H. Hodges,et al.  Linear Flap-Lag Dynamics of Hingeless Helicopter Rotor Blades in Hover , 1972 .

[36]  Troy M. Gaffey,et al.  The Effect of Positive Pitch-flap Coupling (Negative δ 3 ) on Rotor Blade Motion Stability and Flapping , 1969 .

[37]  D. H. Roberta. Hodges,et al.  Stability of elastic bending and torsion of uniform cantilever rotor blades in hover with variable structural coupling , 1976 .

[38]  W. Johnson,et al.  Dynamics of tilting proprotor aircraft in cruise flight , 1974 .

[39]  F. X. Caradonna,et al.  An Experimental Analysis of Dynamic Stall on an Oscillating Airfoil , 1974 .

[40]  F. J. Tarzanin,et al.  Prediction of Control Loads Due to Blade Stall , 1972 .

[41]  R. A. Ormiston.  Techniques for Improving the Stability of Soft Inplane Hingeless Rotors , 1974 .

[42]  F. P. Lentine,et al.  RESEARCH IN MANEUVERABILITY OF THE XH-51A COMPOUND HELICOPTER , 1968 .

[43]  D. K. Berrington.  Design and Development of the Westland Sea Lynx , 1974 .

[44]  Norman D. Ham,et al.  Dynamic Stall Considerations in Helicopter Rotors , 1968 .