A hinged propeller comprising a hub and one or more blades is disclosed. In various embodiments, a blade is connected to the hub via a hinge, wherein at least a substantial part of the blade has a longitudinal axis that is substantially parallel to a line extending radially from a center of the hub, and wherein the hinge has an axis of hinge rotation that is oriented at a non-zero acute angle to a line that is perpendicular, in a plane of rotation of the hub, to said longitudinal axis.

A hinged propeller comprising a hub and one or more blades is disclosed. In various embodiments, a blade is connected to the hub via a hinge, wherein at least a substantial part of the blade has a longitudinal axis that is substantially parallel to a line extending radially from a center of the hub, and wherein the hinge has an axis of hinge rotation that is oriented at a non-zero acute angle to a line that is perpendicular, in a plane of rotation of the hub, to said longitudinal axis.

A magnetic spacer system for a spinner of a rotorcraft includes a first ring of a plurality of magnets secured to the spinner and having an inner surface facing radially inward, and a second ring of a plurality of magnets secured to a nacelle of the rotorcraft and having an outer surface facing radially outward. The first and second rings of multiple magnets are arranged concentrically, and a portion of the inner surface of the first ring of a plurality of magnets and a portion of the outer surface of the second ring of a plurality of magnets have the same polarity to repel one another. In other aspects, the magnetic spacer system may be replaced by a low-friction system.

A magnetic spacer system for a spinner of a rotorcraft includes a first ring of a plurality of magnets secured to the spinner and having an inner surface facing radially inward, and a second ring of a plurality of magnets secured to a nacelle of the rotorcraft and having an outer surface facing radially outward. The first and second rings of multiple magnets are arranged concentrically, and a portion of the inner surface of the first ring of a plurality of magnets and a portion of the outer surface of the second ring of a plurality of magnets have the same polarity to repel one another. In other aspects, the magnetic spacer system may be replaced by a low-friction system.

A propeller blade having a blade body including a blade base, a blade tip, a pressure side surface, and, a suction side surface. Each of the pressure side surface and the suction side surface extend between the blade base to the blade tip. An end plate is provided on the blade body. The end plate is exposed to an airflow and positioned at the blade base. The end plate projects outwardly of at least a portion of one of the pressure side surface and the suction side surface.

Disclosed here are systems for detachable airframe components including detachable nose cones, propeller assemblies and motors. In some example embodiments, the assemblies include a nose cone with a connection receiver, a motor assembly with a rotatable section, where the rotatable section includes torque arms configured to secure with the nose cone connection receiver, and a propeller assembly, configured to connect to the nose cone.

Disclosed here are systems for detachable airframe components including detachable nose cones, propeller assemblies and motors. In some example embodiments, the assemblies include a nose cone with a connection receiver, a motor assembly with a rotatable section, where the rotatable section includes torque arms configured to secure with the nose cone connection receiver, and a propeller assembly, configured to connect to the nose cone.

A propeller blade having a blade body including a blade base, a blade tip, a pressure side surface, and, a suction side surface. Each of the pressure side surface and the suction side surface extend between the blade base to the blade tip. An end plate is provided on the blade body. The end plate is exposed to an airflow and positioned at the blade base. The end plate projects outwardly of at least a portion of one of the pressure side surface and the suction side surface.

An aircraft propulsion system comprises an engine, a propeller drive shaft drivingly engaged with the engine, a propeller for propelling an aircraft and a fan driving cooling air along a flow path in thermal communication with the engine. The engine may be an internal combustion engine or other engine type having heat rejection requirements and the fan may facilitate cooling of the engine. The propulsion system may have a pusher configuration.

A magnetic spacer system for a spinner of a rotorcraft includes a first ring of a plurality of magnets secured to the spinner and having an inner surface facing radially inward, and a second ring of a plurality of magnets secured to a nacelle of the rotorcraft and having an outer surface facing radially outward. The first and second rings of multiple magnets are arranged concentrically, and a portion of the inner surface of the first ring of a plurality of magnets and a portion of the outer surface of the second ring of a plurality of magnets have the same polarity to repel one another. In other aspects, the magnetic spacer system may be replaced by a low-friction system.