The use of composite materials in modern aviation has long been widespread. Combining various methods of design, assembly and testing allows to obtain parts and structures with high strength, reliability and durability. The purpose of this pilot study was to create a mathematical model of the composite rotor blade of a light multipurpose helicopter using an optimal combination of known solutions, as well as to perform static and dynamic tests of prototypes of the blade for model validation. The emphasis is on some of the solutions applied in the design of the blade, and their mapping in a mathematical model. The article describes the methodology and technological process of testing, including operational modal analysis as a promising method for assessing modal characteristics of a structure. The result of the study showed the adequacy of the applied mathematical model.