There is provided a strut assembly for a wing of an aircraft. The strut assembly has a strut having an outboard end, an inboard end, and an elongate body. The outboard end is coupled to the wing of the aircraft, and the inboard end is coupled to a fuselage of the aircraft. The strut assembly further has at least one tensioner member having a first end coupled to the strut. The strut assembly further has a first fitting element having a through opening receiving a first portion of the strut and a bearing surface facing inboard. The strut assembly further has a second fitting element having a through opening receiving a second portion of the strut and a bearing surface facing outboard. The at least one tensioner member maintains tension in the strut, to keep the strut taut and in tension, to prevent or to minimize drooping of the strut.

A blade or wing element includes a plurality of ribs (20) rotatable and/or slidable with respect to one another whereby to vary the aerodynamic configuration of the blade or wing element by causing a twist thereof. A blade or wing or blade or wing assembly, including such a blade or wing element is disclosed, as well as an aerodynamic apparatus such as an aircraft, or a wind turbine. A method of assembling a blade or wing element is also disclosed.

A blade or wing element includes a plurality of ribs (20) rotatable and/or slidable with respect to one another whereby to vary the aerodynamic configuration of the blade or wing element by causing a twist thereof. A blade or wing or blade or wing assembly, including such a blade or wing element is disclosed, as well as an aerodynamic apparatus such as an aircraft, or a wind turbine. A method of assembling a blade or wing element is also disclosed.

Systems and methods for operating control surfaces of an aircraft. The method involves receiving, by an aircraft control system from one or more sensors, deflection information related to a shape and motion of an aircraft, and decomposing, by the aircraft control system, the deflection information into a detected modal state including a first known mode having a first mode strength. The method may further involve determining, by the aircraft control system, a first modal compensation based on the first mode strength, and identifying, by the aircraft control system, a desired control corresponding to a second known mode. The method may yet further involve determining a first control response for a control surface having a first modal weight and a second modal weight, based on the first modal compensation and the first modal weight, and determining a second control response for the control surface based on the desired control and the second modal weight. The method may still further involve generating a control command for the control surface based on the first control response and the second control response.

Systems and methods for operating control surfaces of an aircraft. The method involves receiving, by an aircraft control system from one or more sensors, deflection information related to a shape and motion of an aircraft, and decomposing, by the aircraft control system, the deflection information into a detected modal state including a first known mode having a first mode strength. The method may further involve determining, by the aircraft control system, a first modal compensation based on the first mode strength, and identifying, by the aircraft control system, a desired control corresponding to a second known mode. The method may yet further involve determining a first control response for a control surface having a first modal weight and a second modal weight, based on the first modal compensation and the first modal weight, and determining a second control response for the control surface based on the desired control and the second modal weight. The method may still further involve generating a control command for the control surface based on the first control response and the second control response.

A wing segment for an aircraft includes a first skin element with a material having anisotropic characteristics and a rib element arranged between leading and trailing edges of the wing segment. The first skin element is attached to the rib element such that deformation of the skin element results in a twist of the wing segment with respect to a main extension direction of the wing segment. The wing segment further includes a control unit to control deformation of the skin element in order to adjust the twist of the wing segment to achieve a predetermined twist of the wing segment.

A wing segment for an aircraft includes a first skin element with a material having anisotropic characteristics and a rib element arranged between leading and trailing edges of the wing segment. The first skin element is attached to the rib element such that deformation of the skin element results in a twist of the wing segment with respect to a main extension direction of the wing segment. The wing segment further includes a control unit to control deformation of the skin element in order to adjust the twist of the wing segment to achieve a predetermined twist of the wing segment.

An airplane wing assembly includes a wing, a winglet and a connection element. The wing has a wing box. The wing box is located at a wing tip of the wing and the winglet is connected with the wing by the wing box. The connection element includes a butt joint rib, which is assembled with the wing box, and a center connection, which is assembled with the winglet. The butt joint rib has a first shearing pin hole and a second shearing pin hole, into which are press fitted a corresponding first and a second shearing pin respectively to form interference fit. The center connector has a first sleeve hole and a second sleeve hole.

An airplane wing assembly includes a wing, a winglet and a connection element. The wing has a wing box. The wing box is located at a wing tip of the wing and the winglet is connected with the wing by the wing box. The connection element includes a butt joint rib, which is assembled with the wing box, and a center connection, which is assembled with the winglet. The butt joint rib has a first shearing pin hole and a second shearing pin hole, into which are press fitted a corresponding first and a second shearing pin respectively to form interference fit. The center connector has a first sleeve hole and a second sleeve hole.

A wing-twist aircraft having a wing, an actuation system, a sensor, and/or a controller. The wing may have a wingspan that extends to a wing tip. The wing may further include a spar aligned in a span-wise direction, wherein at least one rib is operatively coupled to the spar. The actuation system may be configured to torsionally rotate the spar, which, in turn, torsionally rotates (pivots) the at least one rib coupled to the spar, thereby twisting the wing. The sensor may be configured to measure a characteristic of the wing, while the controller may be configured to command the actuation system to torsionally rotate the spar based at least in part on input from the sensor.