Abstract: An aircraft including a wing, the end of the wing having a wing tip device, wherein the wing tip device includes a moveable region that is rotatable, about an axis of rotation extending out of the plane of the wing tip device, between: (i) a high-altitude cruise configuration in which the moveable region extends downwardly below the wing; and (ii) a ground-operating configuration in which the moveable region extends rearwardly behind the wing such that the ground clearance of the wing tip device is increased.

Abstract: A morphing aerofoil comprising: a leading edge; a trailing edge; and upper and lower surfaces extending between the leading and trailing edges. An upper thermal actuation member is provided proximate the upper surface; and a lower thermal actuation member is provided proximate the lower surface opposite the upper thermal actuator. The upper and lower thermal actuation members have different thermal expansion coefficients and are positioned such that they cause the trailing edge to deflect when they expand or contract by different amounts in response to a change in ambient temperature, thereby changing a camber of the aerofoil.

Abstract: The invention relates to a flow state sensor (10) for detecting a flow state at a body (16) that may be impinged on by a flow (12). A flow state sensor (10) that is of a simple construction and that is simple to evaluate is characterized in accordance with the invention by at least one frequency detecting device (20) for detecting at least one predefined frequency characteristic of the flow state. The frequency detecting device (20) has at least one oscillation element (22; 22a, 22b, 22c) excitable to resonant oscillatory movement (30) by a flow (12) and having a resonant frequency or natural frequency adapted to the predefined frequency characteristic, especially corresponding to the predefined frequency characteristic. Uses of the flow state sensor (10) in a flow measuring device (62) and in a flow measuring method, and an advantageous production method for the flow state sensor (10) are also proposed.

Abstract: A method of monitoring the performance of an aerodynamic surface of an aircraft. The aircraft is operated during a non-perturbed measurement period such that the flow of air over the surface is at least partially laminar. A parameter is measured which is indicative of the drag of the surface during the non-perturbed measurement period to provide non-perturbed drag data. Air flow is perturbed temporarily over the surface in a perturbed measurement period so that it undergoes a transition from laminar flow to turbulent flow. The parameter is also measured during the perturbed measurement period to provide perturbed drag data. The degree of laminar flow during the non-perturbed measurement period can then be estimated in accordance with the difference between the perturbed drag data and the non-perturbed drag data. An ice protection system can be used to perturb the air flow.

Abstract: A wing comprising at least one aerofoil section and having a leading edge, a trailing edge, an upper surface and a lower surface, wherein a region within the aerofoil section immediately adjacent the leading edge is ventilated so as to establish a sub-static pressure in that region during flight. Also, a method of operating the wing.

Abstract: A shock bump (10) comprising a diverging nose (20) and a converging tail. The tail has at least one plan-form contour line with a pair of concave opposite sides (22, 23). The shock bump provides an improved shape with relatively low drag. Furthermore, the concave shape of the tail tends to promote the development of longitudinal vortices which can reduce shock induced buffet at certain operating conditions.

Abstract: An aerofoil is provided having an upper surface, a lower surface, a leading edge between the upper and lower surfaces at the front of the aerofoil, and a trailing edge between the upper and lower surfaces at the rear of the aerofoil. The leading edge has projection where it meets the lower surface of the aerofoil, and a cove between the projection and upper surface of the aerofoil. A flow vortex is formed in the cove which exhibits increasingly axial flow that retains flow attachment to higher angles of attack.

Abstract: A method of monitoring the performance of an aerodynamic surface of an aircraft. The aircraft is operated during a non-perturbed measurement period such that the flow of air over the surface is at least partially laminar. A parameter is measured which is indicative of the drag of the surface during the non-perturbed measurement period to provide non-perturbed drag data. Air flow is perturbed temporarily over the surface in a perturbed measurement period so that it undergoes a transition from laminar flow to turbulent flow. The parameter is also measured during the perturbed measurement period to provide perturbed drag data. The degree of laminar flow during the non-perturbed measurement period can then be estimated in accordance with the difference between the perturbed drag data and the non-perturbed drag data. An ice protection system can be used to perturb the air flow.

Abstract: The invention relates to a flow state sensor (10) for detecting a flow state at a body (16) that may be impinged on by a flow (12). A flow state sensor (10) that is of a simple construction and that is simple to evaluate is characterised in accordance with the invention by at least one frequency detecting device (20) for detecting at least one predefined frequency characteristic of the flow state. The frequency detecting device (20) has at least one oscillation element (22; 22a, 22b, 22c) excitable to resonant oscillatory movement (30) by a flow (12) and having a resonant frequency or natural frequency adapted to the predefined frequency characteristic, especially corresponding to the predefined frequency characteristic. Uses of the flow state sensor (10) in a flow measuring device (62) and in a flow measuring method, and an advantageous production method for the flow state sensor (10) are also proposed.

Abstract: A shock bump (10) comprising a diverging nose (20) and a converging tail. The tail has at least one plan-form contour line with a pair of concave opposite sides (22, 23). The shock bump provides an improved shape with relatively low drag. Furthermore, the concave shape of the tail tends to promote the development of longitudinal vortices which can reduce shock induced buffet at certain operating conditions.

Abstract: An aerodynamic structure comprising a series of shock bumps (3) extending from its surface. The shock bumps are distributed across the structure with a non-uniform spacing (d1, d2) between the centres and/or edges of adjacent bumps. The non-uniform spacing between the bumps can be arranged to give maximum wave drag alleviation for the minimum number of bumps as a function of the shock strength across the span, leading to minimum wing weight penalties for a given amount of wave drag alleviation.

Abstract: An aerodynamic structure comprising a shock bump (3) extending from its surface. The shock bump is asymmetrical about a plane of asymmetry, and the plane of asymmetry: passes through a centre (6) of the shock bump, is parallel with a principal direction of air flow over the structure, and extends at a right angle to the surface of the structure.

Abstract: An aerodynamic structure (1) comprising a series of shock bumps (3a, 3b, 3c) extending from its surface. The shock bumps are distributed along a line (7) with a smaller mean angle of sweep than an unperturbed shock (4) which would form adjacent to the surface during transonic movement of the structure in the absence of the shock bumps. Instead of being distributed along the line of the unperturbed shock, the shock bumps are distributed along a line which is less swept than the mean angle of sweep of the unperturbed shock. When the structure is moved at a transonic speed; a shock forms adjacent to its surface and the shock bumps perturb the shock (9) so as to reduce its angle of sweep.

Abstract: An aerodynamic structure comprising an array shock bumps (3, 10) extending from its surface, the array comprising: a first series of shock bumps; and one or more shock bumps positioned aft of the first series. Preferably at least one of the one or more shock bumps positioned aft of the first series is offset so that it is not positioned directly aft of any of the shock bumps in the first series. By providing an array of shock bumps instead of a single line, the first series of shock bumps and the one or more shock bumps positioned aft of the first series can be positioned to modify the structure of a shock which forms under a different respective condition.

Abstract: An aerofoil comprising: an upper surface; a lower surface; a leading edge between the upper and lower surfaces at the front of the aerofoil; and a trailing edge between the upper and lower surfaces at the rear of the aerofoil. The leading edge has a projection where it meets the lower surface, and a cove between the projection and the upper surface. A flow vortex is formed in the cove which exhibits increasingly strong axial flow that retains flow attachment to higher angles of attack. The aerofoil may comprise a main wing element or a flap. The novel geometry of the leading edge of the trailing aerofoil enables the leading aerofoil to be shaped in a way that reduces noise.