A method is provided for verifying proper operation of a left elevator tab disposed at an end portion of a left elevator of an aircraft and a right elevator tab disposed at an end portion of a right elevator of the aircraft. Because proper operation of the elevator tabs cannot be directly verified by existing aircraft instrument, the operation of the elevator tabs can be indirectly verified by analyzing flight data of the aircraft. After identification of a verification event, in which the elevator tabs move relative to the elevators, the positions of the left elevator and right elevator can be measured, and differences in the positions of the left elevator and right elevator can indicate proper operation of the left and right elevator tabs.

In an aircraft wing structure where space and weight considerations are a principal concern, there may be significant challenges in providing a moveable slat and/or a spoiler, particularly in combination with one another. A control device for an aircraft includes upper and lower flaps pivotably mountable adjacent to a slot in a wing behind a leading edge, wherein the control device is operable in a lift configuration to move the upper and lower flaps towards each other to abut opposing surfaces of the slot, to permit airflow along the slot.

A method is provided for verifying proper operation of a left elevator tab disposed at an end portion of a left elevator of an aircraft and a right elevator tab disposed at an end portion of a right elevator of the aircraft. Because proper operation of the elevator tabs cannot be directly verified by existing aircraft instrument, the operation of the elevator tabs can be indirectly verified by analyzing flight data of the aircraft. After identification of a verification event, in which the elevator tabs move relative to the elevators, the positions of the left elevator and right elevator can be measured, and differences in the positions of the left elevator and right elevator can indicate proper operation of the left and right elevator tabs.

Methods and apparatus to control a gap between movable aircraft wing components are disclosed. An example apparatus includes a body having a trailing edge and a leading edge. The leading edge is to be coupled to an aircraft wing. The trailing edge is to engage a flap of the aircraft wing. The body includes a structure located between the trailing edge and the leading edge. The structure is to engage the flap to maintain a distance between the body and the flap.

A method for providing a controllable side force to an air vehicle having a vertical stabilizer arrangement includes (a) selectively causing the vertical stabilizer arrangement to generate a first side force in a first side direction to provide the controllable side force, the first side force inducing a corresponding first yaw moment in a first yaw direction; and (b) selectively providing to the air vehicle a second yaw moment in a second yaw direction, the second yaw moment being induced by a force component of an auxiliary force applied to the air vehicle, the force component being in a force direction that is non-parallel with respect to the first side direction and the force component being spaced from a center of gravity of the air vehicle; wherein the second yaw direction is opposed to the first yaw direction. Also disclosed is a corresponding auxiliary yaw generating system.

A method for providing a controllable side force to an air vehicle having a vertical stabilizer arrangement includes (a) selectively causing the vertical stabilizer arrangement to generate a first side force in a first side direction to provide the controllable side force, the first side force inducing a corresponding first yaw moment in a first yaw direction; and (b) selectively providing to the air vehicle a second yaw moment in a second yaw direction, the second yaw moment being induced by a force component of an auxiliary force applied to the air vehicle, the force component being in a force direction that is non-parallel with respect to the first side direction and the force component being spaced from a center of gravity of the air vehicle; wherein the second yaw direction is opposed to the first yaw direction. Also disclosed is a corresponding auxiliary yaw generating system.

An aircraft wing with an array of moveably flight control surfaces is disclosed. Each flight control surface includes a trailing edge with a moveable tab attached to the flight control surface trailing edge. A flight control system coupled to a flight control surface drive system which moves the flight control surfaces; a tab drive system which moves the moveable tabs and one or more aircraft angle of attack sensors. The flight control system stores a set of angular deflections to deflect the tabs upwardly when the angle of attack reaches a threshold.

An aircraft wing with an array of moveably flight control surfaces is disclosed. Each flight control surface includes a trailing edge with a moveable tab attached to the flight control surface trailing edge. A flight control system coupled to a flight control surface drive system which moves the flight control surfaces; a tab drive system which moves the moveable tabs and one or more aircraft angle of attack sensors. The flight control system stores a set of angular deflections to deflect the tabs upwardly when the angle of attack reaches a threshold.

A control system of a hovercraft that includes one engine and one propulsion fan enclosed in a duct in which swivel side flaps are located is described. The control system includes, downstream of the duct, at least three rudders. Each of the rudders operates in the full range of angular position, regardless of the position of the swivel side flaps. A control method of such a hovercraft is also described.

A control system of a hovercraft that includes one engine and one propulsion fan enclosed in a duct in which swivel side flaps are located is described. The control system includes, downstream of the duct, at least three rudders. Each of the rudders operates in the full range of angular position, regardless of the position of the swivel side flaps. A control method of such a hovercraft is also described.