WO2011056082A2

WO2011056082A2 - Aircraft

Info

Publication number: WO2011056082A2
Application number: PCT/PL2010/000110
Authority: WO
Inventors: Edward MARGAŃSKI
Original assignee: Marganski Edward
Priority date: 2009-11-09
Filing date: 2010-11-05
Publication date: 2011-05-12
Also published as: PL389502A1; EP2499042A2; WO2011056082A3

Abstract

The object of the invention is an aircraft provided with a device for creating a constant moment in relation to the axis of rotation of an additional control surface placed at the front of the aircraft at an as large as possible distance from the centre of gravity of the aircraft. The aircraft is characterised in that the control of the aerodynamic vertical force (7) is effected by deflecting control elements (3) pivotably mounted on the rotation axis (4), the deflection of said control elements causing rotation of a balance and control surface (1) mounted rotatably on axis (2), wherein the axis (2) is mounted perpendicularly to the plane of symmetry (5) of aircraft (6) forward of the resultant aerodynamic vertical force (7) generated by the balance and control surface (1).

Description

Aircraft

The object of the invention is an aircraft provided with a device for creating a constant moment in relation to the axis of rotation of an additional control surface placed at the front of the aircraft at an as large as possible distance from the centre of gravity of the aircraft.

The Polish patent specification no. 20191 1 describes a method of control of a flying aircraft of required degree of stability, wherein movable control surfaces placed at the front of the airframe at a large distance forward of the centre of gravity, on which control surfaces a constant aerodynamic force is applied, which force is independent of the angle of attack of the airframe, of the setting angle of the movable control surface and of other configuration parameters of the airframe, are acted upon by means of connections of electrical and/or hydraulic control elements, as the result of which a defined deflection of the control element corresponds to a defined force acting on the movable control surface, wherein the movable control surface is suspended on a transverse axis located forward of the resultant aerodynamic force acting on the movable control surface, and wherein a constant adjustable moment set by the pilot is applied to the transverse axis or wherein the deflection of the movable control surface is changed in order to attain a constant, adjustable by the pilot, pressure difference at selected points of the upper and lower side of the movable control surface.

In that invention the moment applied caused positioning of the additional control surface under a resultant angle in relation to the undisturbed stream of air, providing thereby generation of a vertical force that was essentially dependant only on the controlled moment.

The aircraft according to the invention provided with a control surface that generates controlled vertical force independent of the angle of attack of the aircraft and its configuration, is characterized in that the vertical force is controlled by deflecting control elements mounted pivotably on the rotation axis of the balancing and control surface, which deflection causes tilting of the balancing and control surface mounted rotatably on the axis, whereas the said axis is mounted perpendicularly to the plane of symmetry of the aircraft.

The application of the technical solution according to the invention based on a mechanical system enables in a simple and instant manner changing of the aeroplane balance and its control in the pitch plane, in contrast to solutions wherein a constant controlled moment is applied to the axis of the balance and control surface. In this latter case there is an additional mechanism, which requires additional power supply and in a simple embodiment does not ensure the response time adequate for the use thereof for aircraft control, but is sufficient for aircraft balancing.

In the solution according to the invention it is also possible to use smart composites, which enable combining the control surface with control elements into a complete whole, and deflecting of the control surface is effected by controlled deformation of the surface or of part of it. Example embodiments of the invention are shown in drawings, wherein Fig. 1 represents a top view of an aircraft provided with movable control elements placed along an axis perpendicular to the plane of symmetry of the aircraft, Fig. 2 represents a side view of an aircraft provided with movable control elements placed along an axis perpendicular to the plane of symmetry of the aircraft, Fig. 3 represents a top view of an aircraft provided with movable control elements placed along an axis oblique to the plane of symmetry of the aircraft, Fig. 4 represents a side view of an aircraft provided with movable control elements placed along an axis oblique to the plane of symmetry of the aircraft, Fig. 5 represents a top view of an aircraft provided with movable control elements placed along an axis parallel to the plane of symmetry of the aircraft, Fig. 6 represents a side view of an aircraft provided with movable control elements placed along an axis parallel to the plane of symmetry of the aircraft, Fig. 7 represents an example embodiment of the mechanical steering of the balance and control surface.

In the proposed solution according to the invention no moment is applied to the axis of rotation 2 of the balance and control surface 1 , instead a moment is generated on the balance and control surface 1 itself due to providing the said surface with control elements 3, the deflection of which changes the deflection of the balance and control surface 1 conducing to the change in the angle of attack thereof, and in consequence to the change of the force generated thereby. It can be assumed that this additional moment can be generated aerodynamically in three ways.

To illustrate the above, Fig. 1 and Fig. 2 show an example embodiment of the invention, wherein control elements 3 are placed on axis 4 perpendicular to the plane of symmetry 5 of an aircraft 6. In this solution, when the additional balance and control surface 1 is freely suspended on axis 2 and the profile thereof is symmetrical and with the same configuration of control elements 3 deflected on axis 4 locked in position zero, the system practically does not generate any lift, and consequently does not change the balance of the aircraft and its stability in practical application. Deflecting the control elements 3 by a defined angle changes the angle of attack of the balance and control surface1, and generates thereby a constant force independent of the angle of attack of the aircraft 6 and of the configuration thereof. In other words the force as described above is applied to axis 2 of rotation of the balance and control surface Λ, and the moment required to balance this force acting on an arm defined by the position of the lift on the balance and control surface 1 in relation to the axis 2 of rotation thereof is balanced by the force generated by the control elements 3.

This same effect of aircraft controllability by attaining a constant moment can be achieved by mounting control elements 3 directly on the trailing edge of the balance and control surface 1 as shown in the example embodiment illustrated in Figs. 3 and 4.

Due to friction in the suspension of the balance and control surface 1 in relation to axis 2, a relatively large distance between the point of application of the resultant force generated by the balance and control surface 1 and the axis 2 of rotation thereof is advantageous. The shape of the additional surface alone defined by sweep and taper ratio, position of the axis of rotation and geometry of the control element 3 and position of its axis 4 of rotation must be well optimised. This optimisation applies mainly to the possibility of generating maximum force on the balance and control surface1 under the maximum possible deflection of the control element 3. The third possible way of attaining a constant moment for controlling the aircraft, particularly in the case of the additional balance surface of high sweep and aspect ratio, is shown in an example embodiment illustrated in Figs. 5 and 6. In this case the role of the control element 3 is assumed by the cut off external part of the additional control and balance surface 1 itself. This external part of the control and balance surface Λ upon deflecting it in relation to the basic part thereof generates a moment equal to the force generated by the control elements 3 multiplied by the arm a equal to the distance between axis of rotation 2 of the control and balance surface Λ and the axis of rotation of the control elements 3. All three example embodiments satisfy the basic requirements, and the choice thereof depends on the aerodynamic and structural optimisation for a particular application.

Despite the differences between the example embodiments, they all satisfy the basic condition that the deflection of the control elements 3 by the pilot fulfils the main condition that the force generated by the deflection of this element on the control and balance surface Λ depends on the pilot's will and is independent of the angle of attack of the aircraft 6 and its configuration, and thereby has no impact on its stability.

It should be noted that the deflection of the control elements 3 in relation to the control and balance surface 1 may be effected by direct mechanical steering and also by means of various types of mechanical, electromechanical, hydraulic or pneumatic servo-mechanisms.

Claims

An aircraft provided with a control surface placed prominently forward of the aircraft's centre of gravity, the said surface generating a controlled aerodynamic vertical force independent of the angle of attack of the aircraft and of its configuration, characterised in that the control of the aerodynamic vertical force (7) is effected by deflecting control elements (3) pivotably mounted on the rotation axis (4), the deflection of said control elements causing rotation of a balance and control surface (1) mounted rotatably on axis (2), wherein the axis (2) is mounted perpendicularly to the plane of symmetry (5) of aircraft (6) forward of the resultant aerodynamic vertical force (7) generated by the balance and control surface (1).