An active wing extension includes a body portion substantially parallel to a wing of an aircraft, as if it were an extension of the wing. The body portion is attachable to an aircraft wing and includes multiple controllable airflow modification devices coupled thereto. By virtue of having multiple controllable airflow modification devices, the wing extension is capable of adjusting control surfaces of the multiple controllable airflow modification devices in response to in-flight conditions, to reduce wing loads, improve wing fatigue characteristics, increase range, and/or increase efficiency.

An aircraft has a pilot compartment and a power source, apparatus adapted to control attitude and direction, apparatus adapted to vary power of the power source, sensors sensing at least altitude, airspeed, power level, and aircraft attitude, a CPU coupled to a data repository, to the sensors and to actuators adapted to change the flight attitude and direction and to vary power, and safe flight envelope data and conditions stored in the data repository defining flight conditions at boundaries of safe and unsafe operation. The CPU monitors the sensors while the aircraft is in operation, determines if flight status is outside the safe flight envelope, and if so, drives appropriate actuators to manipulate the apparats adapted to control flight attitude and direction and/or the apparatus adapted to vary power of the power source in a programmed manner until the flight status is within the safe flight envelope.

Aspects relate to aircraft and methods of use for aerodynamic control with winglet surfaces. In an aspect an exemplary aircraft includes a first wing having a first winglet at a distal end of the wing, wherein the first winglet comprises at least a first control surface at a first trailing edge of the first winglet and a second wing having a second winglet at a distal end of the wing, wherein the second winglet comprises at least a second control surface at a second trailing edge of the second winglet.

An active winglet includes a body portion substantially parallel to a wing of an aircraft, as if it were an extension of the wing. The body portion is attachable to an aircraft wing and includes a controllable airflow modification device coupled thereto. By virtue of having a controllable airflow modification device, the winglet is capable of adjusting a control surface of the controllable airflow modification device in response to in-flight conditions, to reduce wing loads, increase range, and/or increase efficiency.

An arrangement of lifting surfaces including a primary lifting surface having a flexural axis extending in the spanwise direction of the lifting surface, a root, and a tip. A first tip device is attached to the tip and has a first lifting surface. A second tip device is attached to the tip and has a second lifting surface. A control system is coupled to the first and second tip devices for moving the first and second lifting surfaces relative to the tip and/or for actively controlling circulation of the first and second lifting surfaces. The control system is operable to change a value of torque effective at the primary lifting surface about the flexural axis. Also, a method of controlling an arrangement of lifting surfaces.

An aircraft wing is disclosed having a root end, a tip end, a span extending between the root end and the tip end, a leading edge, a trailing edge and a chord extending between the leading edge and the trailing edge, and including a main fixed wing portion having an inboard portion adjacent the root end, and an outboard portion adjacent the tip end. A wing tip device attached to the tip end of the wing; and a movable flight control surface connected at the outboard portion of the main fixed wing portion and having a leading edge, a trailing edge and a chord extending between the leading edge and the trailing edge. A ratio of the local chord length of the movable flight control surface to the local chord length of the wing varies in the spanwise direction.

An arrangement of lifting surfaces including a primary lifting surface having a flexural axis extending in the spanwise direction of the lifting surface, a root, and a tip. A first tip device is attached to the tip and has a first lifting surface. A second tip device is attached to the tip and has a second lifting surface. A control system is coupled to the first and second tip devices for moving the first and second lifting surfaces relative to the tip or for actively controlling circulation of the first and second lifting surfaces. The control system is operable to change a value of torque effective at the primary lifting surface about the flexural axis.

A fluid foil has a main fixed portion and a tip portion movably mounted at a tip end of the main fixed portion. The main fixed portion has an upper surface and a lower surface, and the tip portion has an upper surface and a lower surface. The fluid foil is operable in: a) a first configuration in which the upper surface of the tip portion is angled downwardly with respect to the upper surface of the main fixed portion; and b) a second configuration in which the tip portion is rotated upwardly with respect to the first configuration such that the upper surface of the tip portion and the upper surface of the main fixed portion are substantially continuous surfaces. The movement of the tip portion with respect to the main fixed portion is exclusively passively actuated by movement of the foil with respect to a surrounding fluid.

A method of retrofitting a wing of a fixed wing aircraft is disclosed including the steps of providing an existing aircraft wing with a main fixed wing portion, and the main fixed wing portion having a tip end and an existing movable flight control surface connected adjacent the tip end. The existing movable flight control surface is then removed from the main fixed wing portion, and a wing tip device and movable flight control surface are selected as a pair to replace the existing movable flight control surface, with the selected movable flight control surface having an aerodynamic surface of different shape to the shape of the flight control surface removed from the wing. The selected wing tip device and movable flight control surface are then fitted to the main fixed wing portion.

An active wing extension includes a body portion substantially parallel to a wing of an aircraft, as if it were an extension of the wing. The body portion is attachable to an aircraft wing and includes multiple controllable airflow modification devices coupled thereto. By virtue of having multiple controllable airflow modification devices, the wing extension is capable of adjusting control surfaces of the multiple controllable airflow modification devices in response to in-flight conditions, to reduce wing loads, improve wing fatigue characteristics, increase range, reduce torsional loads, alleviate flutter, and/or increase efficiency.