A blade-fold bushing system includes a splined bushing comprising a first plurality of teeth, a castellated bushing comprising a second plurality of teeth and a shaft portion configured to coaxially fit within the splined bushing, and a lock bushing coaxially aligned with the castellated bushing. A support tool for use with a blade-fold bushing system includes an outer head comprising a third plurality of teeth configured to mesh with the first plurality of teeth of the splined bushing, and an inner head comprising a fourth plurality of teeth configured to mesh with the second plurality of teeth of the castellated bushing.

A blade-fold bushing system includes a splined bushing comprising a first plurality of teeth, a castellated bushing comprising a second plurality of teeth and a shaft portion configured to coaxially fit within the splined bushing, and a lock bushing coaxially aligned with the castellated bushing. A support tool for use with a blade-fold bushing system includes an outer head comprising a third plurality of teeth configured to mesh with the first plurality of teeth of the splined bushing, and an inner head comprising a fourth plurality of teeth configured to mesh with the second plurality of teeth of the castellated bushing.

A propulsion unit includes a motor rotor, propeller blades, and a pivot stop. The motor rotor spins about a central rotational axis. The propeller blades, including first and second propeller blades, each having a proximal base mounted to the motor rotor such that the propeller blades are rotatable about the central rotational axis. The second propeller blade is pivotally attached to the motor rotor to pivot about the central rotational axis independent of the motor rotor by a limited angle. The pivot stop mechanically limits an amount of pivoting of the second propeller blade relative to the first propeller blade.

An autogyro includes a frame and a rotor hub coupled to the frame. The autogyro also includes a connector coupled to the rotor hub and configured to couple the rotor hub to a ground-based pre-rotator device to rotate the rotor hub during a vertical take-off operation. The autogyro further includes a plurality of rotor blades coupled to the rotor hub, each rotor blade configured such that rotation of the rotor hub, during the vertical take-off operation, results in twisting the rotor blade from a first blade pitch distribution to a second blade pitch distribution.

A payload delivery device configured to deliver an aircraft deployed payload along a flight path to a predetermined landing destination includes a support member configured to be removably attached to the payload, a flight control and navigation system module configured to control orientation of the plurality of control surfaces while the payload is travelling along the flight path to the predetermined landing destination, a control surface assembly module including a plurality of control surfaces, a rotor assembly including a plurality of rotor blades having a central axis of rotation, and a collective control assembly module including at least one collective servomotor configured to control a plurality of control linkages connected to the plurality of rotor blades.

A payload delivery device configured to deliver an aircraft deployed payload along a flight path to a predetermined landing destination includes a support member configured to be removably attached to the payload, a flight control and navigation system module configured to control orientation of the plurality of control surfaces while the payload is travelling along the flight path to the predetermined landing destination, a control surface assembly module including a plurality of control surfaces, a rotor assembly including a plurality of rotor blades having a central axis of rotation, and a collective control assembly module including at least one collective servomotor configured to control a plurality of control linkages connected to the plurality of rotor blades.

A method of assembling a delivery payload assembly configured to be deployed from an aircraft and travel along a flight path to a predetermined landing destination includes attaching a tail-kit assembly to a first end of a payload, the tail-kit assembly including a rotor blade assembly including a plurality of rotor blades having a central axis of rotation, and a flight control and navigation system configured to control a collective pitch angle of each of the plurality of rotor blades of the rotor blade assembly, configured to control an axial thrust force of the rotor blade assembly, the axial thrust force being at an angle with respect to the central axis of rotation of the rotor blade assembly, and configured to navigate the delivery payload assembly along the flight path to the predetermined landing destination. The method further includes removing the tail-kit assembly from the payload after the payload is delivered to the predetermined landing destination.