manufactured by Trendak Aviation Company during the project “Research and development works on innovative construction of aircrafts of weight over 560 kilograms”. Discusses structural advantages of the new rotor hub connector according to other construction. Also were raised issues related to the load of the gyroplane rotor during the flight, in particular the load of rotor blades root, during a gyroplane break manoeuvre, according to conning angle of rotor hub connector. The disadvantages of using the structural dihedral angle in teetering rotors are also presented, focusing on the rotor aeroelastic instability so-called waving, which from the literature analysed is concerned only with two blades teetering rotors. Performed a coarse analysis in SMOG program, prepared at the Institute of Aviation for the analysis of helicopter and gyroplanes rotors. The stability analysis of the rotor for a number of structural dihedral angle and blades setting pitch was performed. Basis of this analysis the stability boundary were determined for the analysed gyroplane rotor with connector hub with positive coning angle of 2.8o. .

aircrafts of weight over 560 kilograms at the company Trendak Aviation”. The work outlines the basic properties of the gyroplane vibration and gives their sources. The research focused on the gyroplane main rotor vibration related inter alia to the rotor imbalance as well as rotor hub connector construction. Tested rotors consisted of three different types of gyroplane rotor blades and innovative universal hub connector with positive coning angle of 2.8º. The article summarized the basic properties of three types of gyroplane the rotor blade, marks advantages of use hub connector witch constructional dihedral angle. Discusses the principle of operation of measuring device, tests methodology starting from instrument calibration. The results of the measurements are shown in the graphs in polar coordinates. The vibration measurement is carried out in two axes, in x-axis, longitudinal, along the rotor radius and in y-axis, perpendicular to the x-axis, in the direction of the chord of the rotor blades.