Modal analysis of an underwing search-light fairing

  • Jarosław Bednarz AGH University of Science and Technology in Cracow
  • Wojciech Lisowski AGH University of Science and Technology in Cracow
Keywords: modal analysis, experimental structural dynamics, mode shapes


Many applications of aircraft require using dedicated elements of equipment attached to the fuselage or wings. These elements change aerodynamic properties of the aircraft. They modify spatial mass distribution and local stiffness in the attachment place. Structural dynamics of the modified airframe is usually investigated with use of the numerical analysis techniques. Verification of results of such the analysis is carried out experimentally. The basic method of testing is the experimental modal analysis. In the paper, there is presented an exemplary application of the experimental modal analysis to testing of a modified airplane structure with a search-light covered by its fairing attached under a wing. The described experiments consisted of the ground as well as the in-flight tests. The paper reports description and results of the experiments.


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