A flap system driving a leading-edge flap between retracted and extended positions comprises a leading-edge flap, an actuator, first, second and third fixed links, first and second connecting links, and an auxiliary link. The first, second and third fixed links are rotatably supported on respective first, second and third structurally fixed points by respective first, second and third support joints. The first fixed link couples with an end of the first connecting link, which is coupled with a first flap joint at another end. The second fixed link rotatably couples with a central region of the first connecting link. The third fixed link rotatably couples with an end of the second connecting link, which is coupled with a second flap joint at another end. The second connecting link couples with the first fixed link through the auxiliary link, each at positions inside of the respective ends.

A vehicle, such as a micro-aerial vehicle or underwater vehicle, includes at least one lift structure, such as a low-aspect-ratio wing or a fin, respectively. The at least one lift structure comprises one or more alulas. A leading surface of each alula is (a) flush with a leading surface of the lift structure or (b) offset from the leading edge of the lift surface by up to approximately 10% of the chord length of the lift structure. The length of each alula is no more than approximately 20% of a lift structure length corresponding to the lift structure. In various embodiments, the alula is deflected or canted with respect to a plane defined by the lift structure. In an example embodiment, the alulas may be slid or translated along at least a portion of the span of the lift structure.

A vehicle, such as a micro-aerial vehicle or underwater vehicle, includes at least one lift structure, such as a low-aspect-ratio wing or a fin, respectively. The at least one lift structure comprises one or more alulas. A leading surface of each alula is (a) flush with a leading surface of the lift structure or (b) offset from the leading edge of the lift surface by up to approximately 10% of the chord length of the lift structure. The length of each alula is no more than approximately 20% of a lift structure length corresponding to the lift structure. In various embodiments, the alula is deflected or canted with respect to a plane defined by the lift structure. In an example embodiment, the alulas may be slid or translated along at least a portion of the span of the lift structure.

A wing for an aircraft, including a main wing, a slat, and a connection assembly movably connecting the slat to the main wing. The connection assembly includes an elongate slat track with a front end mounted to the slat and a rear end and an intermediate portion mounted to the main wing by a roller bearing, and includes a guide rail mounted to the main wing and a first roller unit mounted to the slat track rear end and engaging the guide rail. The roller bearing includes a second roller unit mounted to the main wing and engaging a slat track intermediate portion engagement surface. The slat track has an upper and lower flange and at least one web. The second roller unit is arranged in a recess between the upper and lower flanges and engages the engagement surface provided at the upper and/or lower flange.

A wing for an aircraft, including a main wing, a slat, and a connection assembly movably connecting the slat to the main wing. The connection assembly includes an elongate slat track with a front end mounted to the slat and a rear end and an intermediate portion mounted to the main wing by a roller bearing, and includes a guide rail mounted to the main wing and a first roller unit mounted to the slat track rear end and engaging the guide rail. The roller bearing includes a second roller unit mounted to the main wing and engaging a slat track intermediate portion engagement surface. The slat track has an upper and lower flange and at least one web. The second roller unit is arranged in a recess between the upper and lower flanges and engages the engagement surface provided at the upper and/or lower flange.

Certain aspects of the present disclosure provide techniques for an aerodynamic surface actuation system, including: a plurality of outer tracks, wherein each outer track of the plurality of outer tracks include: an inner roller channel; and an outer roller channel positioned above the inner roller channel; an aerodynamic surface connected to a carrier, wherein the carrier includes: a plurality of rollers configured to move within inner roller channels of the plurality of outer tracks; and a carrier rack; a plurality of fixed rollers mounted to a plurality of longitudinal structural elements in an aerodynamic structure, wherein the plurality of fixed rollers are disposed within outer roller channels of the plurality of outer tracks; and a plurality of fixed racks, wherein each fixed rack of the plurality of fixed racks is mounted to a longitudinal structural element of the plurality of longitudinal structural elements.

Certain aspects of the present disclosure provide techniques for an aerodynamic surface actuation system, including: a plurality of outer tracks, wherein each outer track of the plurality of outer tracks include: an inner roller channel; and an outer roller channel positioned above the inner roller channel; an aerodynamic surface connected to a carrier, wherein the carrier includes: a plurality of rollers configured to move within inner roller channels of the plurality of outer tracks; and a carrier rack; a plurality of fixed rollers mounted to a plurality of longitudinal structural elements in an aerodynamic structure, wherein the plurality of fixed rollers are disposed within outer roller channels of the plurality of outer tracks; and a plurality of fixed racks, wherein each fixed rack of the plurality of fixed racks is mounted to a longitudinal structural element of the plurality of longitudinal structural elements.

Flight control surface actuation systems including skew detection systems and associated methods. A flight control surface actuation system includes a skew detection system configured to generate a skew detection signal that represents a skew condition of a flight control surface. In some examples, the skew detection system includes a skew lanyard and a detection mechanism assembly (DMA) configured to detect a lanyard displacement of the skew lanyard and to generate an analog lanyard displacement signal. In some examples, the skew detection system includes a hybrid sensing actuator that includes an actuator output and an actuator output position sensor directly coupled to the actuator output. Methods of utilizing a flight control surface actuation system include detecting a skew condition in the flight control surface utilizing DMAs and/or hybrid sensing actuators.

A wing leading-edge device is disclosed having a slat body having a front side with a forward skin and a back side with a rearward skin, and at least a drive arrangement having at least one lug and a slat track, wherein the back side extends between an upper spanwise edge of the forward skin and a lower spanwise edge of the forward skin. The back side is defined by a continuously curved profile contour for receiving a fixed leading edge, and the at least one lug is at least partially arranged between the back side and the front side. The slat track is coupled with the first lug. The connection points to the slat body are shifted far forward to improve the load introduction and reduce moments acting on the drive mechanism.

A wing leading-edge device is disclosed having a slat body having a front side with a forward skin and a back side with a rearward skin, and at least a drive arrangement having at least one lug and a slat track, wherein the back side extends between an upper spanwise edge of the forward skin and a lower spanwise edge of the forward skin. The back side is defined by a continuously curved profile contour for receiving a fixed leading edge, and the at least one lug is at least partially arranged between the back side and the front side. The slat track is coupled with the first lug. The connection points to the slat body are shifted far forward to improve the load introduction and reduce moments acting on the drive mechanism.