A flexible blade neck of a helicopter rotor blade is bridged by a torsion gid sleeve for the blade angle adjustments. The radially outer end of the blade neck and sleeve are rigidly connected to the wing section of the blade. The radially inner end of the blade neck forms a blade root which is secure to the rotor head or hub. Additionally, the radially inner ends of the blade root and of the sleeve are interconnected by a ball and socket arrangement permitting a universal movement between the sleeve and the blade neck, thereby decoupling sleeve movements from the blade neck and vice versa.