Investigation of dynamic stresses of tail beam of an MI‐8 helicopter

Abstract Results of theoretical and experimental research of stresses in the skin of a tail beam of an Mi‐8 helicopter at resonant dynamic loading are discussed in this paper. It is shown that resonant tests of the object with an appropriate choice of configuration of internal and external constraints are one of the most effective and economical ways to achieve the necessary result. It is also obvious that the choice of a configuration for the complex dynamic system should be solved on the basis of a careful preliminary analysis of expected dynamic properties. First of all, the research that was performed shows the very significant effect of the elasticity of internal and external constraints on the dynamic properties of real aircraft components at full‐scale dynamic testing. On other hand, it is shown that the correct modelling of a complex elastic system and its constraints allows one to adequately describe the dynamic properties of the real structure and to obtain good coincidence with experimental data.