A blade for cycloidal rotor or propeller is provided with means to dynamically change within each revolution: its relative pivot point location along chord, extend or retract trailing edge, make actuated or passive turns of trailing edge flap, dynamically control stiffness of at least the flexible trailing edge, open or close strips covering much of blade surface area to allow flow through the blade. These features will enable the control system to continually adjust each blade to its immediate operating environment along the orbit.

A blade for cycloidal rotor or propeller is provided with means to dynamically change within each revolution: its relative pivot point location along chord, extend or retract trailing edge, make actuated or passive turns of trailing edge flap, dynamically control stiffness of at least the flexible trailing edge, open or close strips covering much of blade surface area to allow flow through the blade. These features will enable the control system to continually adjust each blade to its immediate operating environment along the orbit.

Embodiments are directed to systems and methods for providing a control link for an aircraft in which the control link comprises an impact-resistant structure with a redundant load path. The control link has an inner structure that is sized to carry the anticipated load of the flight control system and to meet all safety factors. The control link also has an outer structure that is sacrificial and configured to absorb impact damage during operation, thereby protecting the inner structure. The outer structure is also designed to carry the anticipated load of the flight control system on its own, independent of the inner structure, and to meet all safety factors. If the outer structure fails, the inner structure allows for continued safe operation of the flight control system. The space or cavity between the inner and outer structures may be filled with a material, such as a closed-cell foam, to improve the impact resistance of the outer structure.

A tip gap monitoring system for a ducted aircraft having a proprotor system including a duct and a plurality of proprotor blades includes sensors coupled to the proprotor system. The sensors are configured to detect one or more parameters of the proprotor system to form a plurality of sensor measurements. The tip gap monitoring system also includes a flight control computer in data communication with the sensors. The flight control computer includes a tip gap measurement module configured to determine a tip gap distance between the duct and the proprotor blades based on the sensor measurements.

A tip gap control system for a ducted aircraft includes a flight control computer including an inner duct surface control module configured to generate an inner duct surface actuator command and a proprotor system in data communication with the flight control computer. The proprotor system includes a duct having active inner duct surfaces movable into various positions including a retracted position and an extended position. The proprotor system also includes proprotor blades surrounded by the duct and one or more actuators coupled to the active inner duct surfaces. The one or more actuators move the active inner duct surfaces between the various positions based on the inner duct surface actuator command, thereby controlling a tip gap between the proprotor blades and the duct.

A tip gap control system for a ducted aircraft includes a flight control computer including a blade length control module configured to generate a blade tip actuator command and a proprotor system in data communication with the flight control computer. The proprotor system includes a duct and proprotor blades surrounded by the duct. Each of the proprotor blades includes an active blade tip movable into various positions including a retracted position and an extended position. The tip gap control system also includes one or more actuators coupled to the active blade tips. The one or more actuators move the active blade tips between the various positions based on the blade tip actuator command, thereby controlling a tip gap between the proprotor blades and the duct.

Rotary electric engines, aircraft including the same, and associated methods. A rotary electric engine includes a nacelle, a fan configured to generate thrust, a stator operatively coupled to the nacelle, and a rotor operatively coupled to the fan. The fan includes a plurality of fan blades. The rotor includes a plurality of rotor magnets operatively coupled to respective blade tips of the fan blades. The stator includes a plurality of field coils configured to produce a magnetic interaction between the field coils and the rotor magnets to rotate the fan. In examples, the stator is configured to rotate each field coil relative to the nacelle. In examples, an aircraft includes one or more rotary electric engines pivotally mounted within engine mount regions. In examples, a method of operating an aircraft includes operating one or more rotary electric engines in a vertical lift configuration and in a forward flight configuration.

A proprotor system for a ducted aircraft includes a duct and proprotor blades surrounded by the duct. Each proprotor blade is rotatable about a respective pitch change axis. The proprotor blades are configured to change collective pitch about the pitch change axes. The proprotor blades are extendable along the pitch change axes into various positions including a retracted position and an extended position. The proprotor blades change between the retracted position and the extended position based on the collective pitch of the proprotor blades, thereby controlling a tip gap between the proprotor blades and the duct.

One embodiment is a rotor system comprising a rotor duct; at least one rotor blade, wherein the at least one rotor blade comprises an outboard end; a tip extension mechanism affixed at the outboard end of the at least one rotor blade, wherein the tip extension mechanism comprises at least one shim, the at least one rotor blade with the tip extension mechanism affixed thereto comprising an extended rotor blade; and a blade tip affixed to an outboard end of the extended rotor blade, wherein the blade tip is affixed to the extended rotor blade via at least one removable fastener.

The invention relates to a blade (3) of a fan (1) of a turbomachine having a structure made of a composite material comprising a fibrous reinforcement (5) obtained by three-dimensional weaving and a matrix in which the fibrous reinforcement (5) is embedded, the fibrous reinforcement (5) comprising first strands (9) having a predetermined elongation at break, a portion of the fibrous reinforcement (5) further comprising second strands (10) having an elongation at break higher than that of the first strands (9).