Abstract: A mounting system for mounting a blade to a rotor body includes a pitch control mechanism including an anchor and a pitch change rod extending radially outwardly from the anchor to join to a base of the blade. The anchor and the rod are rotatable about the longitudinal axis of the rod to vary the blade pitch. The pitch control mechanism further includes a torque-transmitting formation between the blade and the anchor such that pitch-varying torque can be transmitted to the blade through the torque-transmitting formation while allowing relative radial movement between the blade and the anchor. The system includes a primary bearing formation, which transmits blade centrifugal loads to the rotor body while accommodating variation of the blade pitch, and secondary bearing formation, which transmits pitch change mechanism centrifugal loads to the rotor body while accommodating rotation of the anchor and the rod during variation of the blade pitch.

Abstract: A propeller arrangement has a first propeller assembly providing a row of first propellers, and a second propeller assembly, rearward of the first propeller assembly, providing a row of second propellers. The first and second propellers are radially extendable and retractable. The propeller arrangement further has a control system for controlling the extension and retraction of the first and second propellers. The control system is arranged such that when the propellers of one of the first and second propeller assemblies extend, the propellers of the other of the first and second assemblies retract.

Abstract: A mounting system for mounting a blade to a rotor body includes a pitch control mechanism including an anchor and a pitch change rod extending radially outwardly from the anchor to join to a base of the blade. The anchor and the rod are rotatable about the longitudinal axis of the rod to vary the blade pitch. The pitch control mechanism further includes a torque-transmitting formation between the blade and the anchor such that pitch-varying torque can be transmitted to the blade through the torque-transmitting formation while allowing relative radial movement between the blade and the anchor. The system includes a primary bearing formation, which transmits blade centrifugal loads to the rotor body while accommodating variation of the blade pitch, and secondary bearing formation, which transmits pitch change mechanism centrifugal loads to the rotor body while accommodating rotation of the anchor and the rod during variation of the blade pitch.

Abstract: A propeller arrangement has a first propeller assembly providing a row of first propellers, and a second propeller assembly, rearward of the first propeller assembly, providing a row of second propellers. The first and second propellers are radially extendable and retractable. The propeller arrangement further has a control system for controlling the extension and retraction of the first and second propellers. The control system is arranged such that when the propellers of one of the first and second propeller assemblies extend, the propellers of the other of the first and second assemblies retract.