Research of the Influence of Main Rotor Blades on Loads Acting on the Helicopter Fuselage during an Emergency Landing

This paper considers the calculation models of a helicopter main rotor that allow estimating the influence of the elasticity of blades and the nature of their fastening on the results of strength analysis of the helicopter fuselage airframe during an emergency landing. An analysis was carried out of the influence of the horizontal hinge of the main rotor hub on the transfer of loads from the blades to the gearbox under emergency landing conditions. The values of the influence coefficient of blade masses on the vertical load acting on the main rotor shaft were determined for light, medium and heavy helicopters. An assessment was made of the influence of the main rotor rotation speed on the vertical force transmitted to its shaft.