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Aviation aircraft will be subjected to a large number of complex random vibration loads during service， and its structure is prone to vibration fatigue，which leads to damage or even failure，which can cause serious losses. The stress intensity factor（SIF）solution method for cracked beams under random vibration loading is investigated，and a time-domain method based on Hudson's theory is proposed to estimate the vibration fatigue crack growth life by combining with the Paris formula. The theoretical analysis and vibration fatigue test are conducted on a typical cantilever beam as an object. The results show that the life prediction results of the proposed time-domain method based on the Hudson's theory is better than that of the experimental estimation results，which can verify that the method can effectively describe the random vibration crack growth behavior.

Ground vibration test is an important part of aircraft model development and strength verification. In aircraft ground vibration test，an appropriate excitation scheme can significantly shorten the test's period and improve the accuracy of mode identification. In this paper，QR decomposition based on the finite element model is used for global planning of exciter placement，and mode participation is introduced to evaluate the plan's exciting efficiency. The multivariate mode indicator function is used to optimize the exciting force vector for closely spaced modes. Finally，these methods are verified in a small general aircraft's ground vibration test，which significantly improves the test's efficiency and reduces the difficulty of closely spaced modes identification. The excitation scheme optimization method adopted in this article has high engineering application value.

Experimental modal analysis is a method of measuring the natural vibration characteristics of a structure through experiments. The analysis results are mainly used to modify the structural dynamic models and provide data support for structural dynamics，aeroelastic analysis and vibration control design. This article systematically reviews the research progress of experimental modal analysis methods at home and abroad，starting from two aspects：classic experimental modal analysis methods and modern modal analysis methods，and summarizes the basic principles of the two mainstream methods，the classic phase resonance method and the phase separation method， briefly introduces the experimental modal analysis methods developed in recent years，and summarizes the characteristics of different modal analysis methods. Finally，the current problems and possible future development trends of experimental modal analysis methods are given.

The ground vibration test of full-scale aircraft has the characteristics of multiple coordination units, complex system, long implementation time and high risk. Facing the need of efficient development of advance aircraft, it is necessary to improve the capability of the test by introducing the digital means. In this paper, the flow of ground vibration test in traditional mode is summarized, the elements of digital test are analyzed, and the digital test programme is constructed preliminarily. It is pointed that the current digital collaboration model has significant benefits in reducing experimental risks and improving experimental efficiency. In the future, it is necessary to further promote the integration of digital and real simulation and application platform development to promote the mature implementation of digitalization.

Hypersonic vehicle is subjected to severe aerodynamic load and aerodynamic heating during the flight.Thus structural dynamic stability and response caused by aerodynamic force and aerodynamic heating should be fully considered in the design process of structure,in hypersonic vehicles the thermal flutter is one of the key parts. In this paper,the development of thermal flutter research is reviewed,various existing methods for thermal flutter research are summarized,including thermal modal test,thermal flutter simulation analysis and wind tunnel test. On this basis,the research status and existing problems of ground flutter test,which can be used in the study of thermal flutter,are summarized,and the future development trend of ground thermal flutter test is prospected.