A cycloidal rotor system having airfoil blades travelling along a generally non-circular, elongated and, in most embodiments, dynamically variable orbit. Such non-circular orbit provides a greater period in each revolution and an optimized relative wind along the trajectory for each blade to efficiently maximize lift when orbits are elongated horizontally, or thrust/propulsion when orbits are vertically elongated. Most embodiments, in addition to having the computer system controlled actuators to dynamically vary the blade trajectory and the angle of attack, can also have the computer system controlled actuators for dynamically varying the spatial orientation of the blades; enabling their slanting motion upward/downward and/or backsweep/forwardsweep positioning to produce and precisely control a variety of aerodynamic effects suited for providing optimum performance for various operating regimes, counter wind gusts and enable the craft to move sideways. Thus a rotor is provided, which when used in a VTOL rotorcraft, will require lower engine power to match or exceed the operating performance of VTOL rotorcrafts equipped with prior art cycloidal rotors, this rotor also offers increased efficiency and decreased required power when used for generating the propulsive force for various vehicles or used as a fan.