The present invention provides a stiff in-plane and/or soft in-plane rotor head for a rotorcraft. The invention includes a vertically extending rotor shaft, a center hub disposed on the rotor shaft for conjoint rotation therewith, and a plurality of outer hubs at the opposite ends of the center hub coupled thereto through a mechanical attachment for conjoint rotation therewith, such that the outer hub is also capable of an angular range of teetering and/or lead-lag movement relative to the center hub. A plurality of rotor blades is coupled to the rotor shaft through the center hub and outer hubs by a constant velocity joint that enables the blades to be rotated in a common plane about the axis of the rotor shaft while controlling the respective pitches of the blades such that any other relative in-plane and out-of-plane movements of the blades during rotation is allowed.
