WO2011009492A1

WO2011009492A1 - Selective aileron system

Info

Publication number: WO2011009492A1
Application number: PCT/EP2009/059584
Authority: WO
Inventors: Alexander Krüger
Original assignee: Krueger Alexander
Priority date: 2009-07-24
Filing date: 2009-07-24
Publication date: 2011-01-27

Abstract

The present invention relates to an aileron control system (100) comprising a coupling mechanism (108, 109) for mechanically and selectively transmitting a steering force from a steering part (106) to a subset of ailerons (105) out of a plurality of ailerons (104, 105).

Description

Selective Aileron System

The present invention is directed to a selective aileron system, in particular an aileron control system with features according to claim 1.

Ailerons are hinged control surfaces attached to the trailing edge of an airfoil, in particular a wing of for example a fixed-wing aircraft. Ailerons are used to control the aircraft in roll. Typically, two ailerons on two different wings, e.g. a left wing and a right wing, are interconnected so that one goes down when the other one goes up; the down-going aileron increases the lift on its wing while the up-going aileron reduces the lift on the other wing, producing a rolling moment about the longitudinal axis of the aircraft. An unwanted side- effect of aileron operation is adverse yaw, a yawing moment in the opposite direction to the turn generated by the ailerons. As an aircraft rolls, adverse yaw is caused primarily by the fore-aft tilting of the lift vectors on the left and right wings. The rising wing has its lift vector tilt back, producing an aft force component. The descending wing has its lift vector tilt forward, producing a forward force component. There is also often an additional adverse yaw contribution from a profile drag different between the up-aileron and down-aileron wing tips.

Adverse yaw may be partly compensated by the use of the rudder, which results in a side force on the vertical tail which creates an opposing favourable yaw moment. Another method is by differential ailerons, which have been rigged such that the down-going aileron deflects less than the upward-moving one.

DE 721 833 discloses a differential control for ailerons coupled to flaps, in which the actuation levers for flaps and ailerons are connected to one another via force-transmitting parts such that the ailerons may be actuated by themselves while when using both types of control surfaces as flaps, both types of control surfaces are actuated differentially, i.e. deflected differently. US 6,554,229 discloses an aircraft aileron system comprising two panels which are located at the rear portion of a wing, the panels being independently hinged at their leading edges. For roll control of an aircraft during cruise, the aileron panel on the one side only is deflected up while the aileron panel on the other side remains in its neutral position. Thus, adverse yaw or rotation about the vertical axis of the aircraft is avoided. Each of the ailerons can be modulated independently to deflect to any degree in order to provide the roll rate desired, or be deflected simultaneously for flight path control or airbrakes. However, this document does not give any description by what technical means such an operation of the aileron shall be achieved.

German airworthiness regulations for aerodynamically-steered ultra light aircraft (LTF-UL 2003) assume for the required values of operating force for control surfaces that a simple lever system, i.e. mechanical means, is used.

A problem to be solved by the invention may thus be stated as to provide an aileron control system by which adverse yaw may be avoided while simplifying compliance with airworthiness regulations.

This problem is solved by the subject-matter of the independent claims, the subject-matter of the dependent claims describing advantageous embodiments of the invention. Features of different embodiments of the invention may be combined among or between embodiments.

The present invention provides a selective aileron system, in particular an aileron control system comprising advantageously a coupling mechanism for mechanically and selectively transmitting a steering force from a steering part to a subset of ailerons out of a plurality of ailerons. The subset of ailerons comprises in particular only an active aileron, in particular at least one active aileron, more particularly only one active aileron out of a plurality of ailerons (particularly of active and inactive ailerons), in particular two ailerons.

Preferably, the transmission of the steering force is implemented by mechanically and selectively coupling the steering part with the subset of ailerons. Within the framework of this invention, the term of coupling denotes a stable connection, in particular a mechanical connection or producing a stable, in particular mechanical connection between parts of the aileron control system, especially for transfer of forces (in particular a steering force) and/or a movement of parts or components, respectively. A coupling may comprise a form fit, a force fit and/or a mechanical connection by other parts such as screws and/or bolts and/or nuts and/or nails and/or rivets supporting a stable and secure connection between components of the aileron control system.

An aileron control system is in particular meant to denote technical means for exerting physical control over aircraft control surfaces, in particular ailerons. The coupling mechanism is advantageously designed to comprise only mechanical parts and preferably no hydraulic, electronic or electric parts, in particular no hydraulic, electronic or electric parts for relay and/or amplification of (steering) forces between parts of the aileron control system. Thus, an actuation of ailerons by applying a steering impulse or input by e.g. a person such as a pilot becomes possible without using electronic devices such as for example a fly-by-wire system. The steering impulse or input is transformed by the aileron control system into the steering force. An active aileron in the context of this invention denotes in particular an aileron which is meant to be deflected and/or activated and/or actuated (by the steering force) in order to influence flight control or the state of movement of the aircraft, respectively. The steering force (impulse) is applied to the steering part in a direction denoted as a steering direction. So if the steering part is moved to the right, the steering direction shall be defined as a right steering direction; if the steering part is moved to the left, the steering direction shall be defined as a left steering direction. The anti-steering direction shall be defined as a left anti- steering direction in case of a right steering direction, and as a right anti- steering direction in case of a left steering direction. In case of a right steering direction, the aircraft is guided into a preferably right roll, in case of left steering direction, the aircraft is guided into a preferably left roll. The steering impulse is transferred as a steering force from the steering part by mechanical means to the active aileron. The active aileron thus in particular is located at the side of an aircraft which is located in the steering direction. According to the present invention, an active aileron belongs to a subset of ailerons out of a plurality of ailerons located on an aircraft. In particular, the number of elements of that subset is smaller than the total number (plurality) of ailerons on the aircraft, and the subset comprises only active ailerons. All elements of the subset of ailerons preferably lie on the same side of the aircraft or are built into the same wing, respectively. The terms of active aileron and subset of ailerons shall be used synonymously within the framework of this invention. The coupling mechanism transfers a steering force preferably only to the subset of ailerons and not to any ailerons which are inactive. An inactive aileron in the context of this invention denotes in particular an aileron which is meant to not be deflected or activated (by the steering force) in order to influence flight control or the state of movement of the aircraft, respectively. Rather, the inactive aileron shall not have any influence on the flight path. An inactive aileron shall remain in particular in its neutral position and is meant to not react to a steering force applied to the steering part. In particular, movement of the steering part into a steering direction is enabled without transferring a steering force to an inactive aileron.

Any frames, rails, rods, levers and other structural mechanical parts of the aileron control system may be made of or comprise a metal and/or an alloy (in particular a metal alloy). According to the invention it however is also possible to use wood or plastic materials for forming at least parts (in particular frames, rails, rods and/or levers) of the aileron control system. Any rods, rails or frames comprised by the aileron control system may be formed as flat and/or cuboid rods, however also round and/or cylindric rods may be used in accordance with the invention.

The steering part advantageously is part of the aileron control system and may for example be a joystick and/or a yoke and/or a control column and/or a control stick and/or a side stick. Thus, the steering part forms means for influencing flight control by in particular human operation. A movement of the steering part in the following refers to a movement of the upper end of the steering part, in particular a part of the steering part which is designed for human operation.

The steering part, in particular a middle portion of the steering part, may be advantageously pivoted on a steering pivot on a centre rod or rail, with a lower portion or lower end portion of the steering part extending below the centre rail. The steering pivot preferably comprises a screw connection or any other mechanical connection which enables movement of the steering part in a swinging manner to the left and the right, in particular a relative movement between the steering part and the centre rail.

The centre rail may on both of its ends be provided with an embedding part for embedding or attaching the aileron control system into or to structural parts of an aircraft, in particular the airframe. Advantageously, the aileron control system may be fixed to the aircraft by a stable mechanical connection (e.g. a force fit and/or a form fit). The aileron control system is preferably embedded into the aircraft or its airframe in the cockpit region such that the steering part may be operated by the pilot. The embedding part may for example comprise a clip and/or a tongue which engages into its counterpart on the airframe such as for example a groove or a hole.

A centre frame, in particular a rectangular frame (which may be quadratic in its outline) is attached by a fixed mechanical connection (e.g. a form fit and/or force fit and/or an adhesive bond) to the centre rail such that it extends above and below the centre rail (and/or to two different sides of the centre rail) and to both sides of the steering pivot. Advantageously, the centre frame extends to equal distances above and below the centre rail and left and right of the steering pivot position. Advantageously, the steering pivot is located at the geometric centre of the centre frame. Preferably, the embedding part is formed as a tongue which engages in a hole such that a swinging or rocking motion of the aileron control system or the centre frame, respectively, is made possible preferably around an axis in the longitudinal direction of the centre rail. The rocking motion therefore takes place in a direction which is preferably parallel to a longitudinal or fore-aft direction of the aircraft. This allows for movement of the steering part in a forward and backward direction. Cables or wires for actuating the elevators may be attached to an elevator connecting part, in particular a loop or hole formed on or in preferably a lower portion (more preferably, a centre lower portion) of the centre frame. Thus, a swinging motion of the centre frame (in particular, an upper part of the centre frame) in a rearward or forward direction will enable the respective actuation of the elevators in an upward or downward direction.

The aileron control system further advantageously comprises a pulley system comprising at least two rotational pulley parts and at least two pulling parts for actuating traction parts and thus transferring the steering force to the aileron. At favourably equal distance from the steering pivot position, two transmission levers are pivoted on transmission pivots on the centre rail in particular with their central portion such that both transmission levers in a neutral position extend approximately parallel to the longitudinal dimension of the steering part, in particular above and below the centre rail. The transmission levers may be pivoted in a cavity formed into the centre rail or may be attached to a side surface of the centre rail. The transmission pivots may be formed in a fashion equal or similar to the fashion of the steering pivot. At one of their ends, preferably at their upper end or in a region towards the upper end, each transmission lever is advantageously provided with a rotational pulley part or transmission rotational pulley part, in particular a wheel and/or pulley wheel, the radial direction of which being in parallel to the plane of the centre frame. A groove for guiding a cable or teeth for guiding chain along the circumference of the rotational pulley part may be formed into the circumference of the transmission rotational pulley part. The transmission rotational pulley part may thus be alternatively formed as a pinion or cogwheel, respectively.

Preferably, the transmission rotational pulley parts are mounted on a side surface of the transmission levers and point with their free diametric surface to different side of the centre frame plane. In particular, the radial plane of the transmission rotational pulley parts does not intersect or lie in a plane defined by components of the main frame. Thereby, any pulling part guided by the transmission rotational pulley part will not interfere with the centre frame.

According to one embodiment of the invention, a pulling part, in particular a chain and/or a rope and/or a cable, is lead around each transmission rotational pulley part, one end of the pulling part being attached by a fixed mechanical connection such as a screw connection or an adhesive bond to the steering part, in particular an upper region of the steering part. The other ends of the pulling parts are attached to traction parts for transfer of steering force to the aileron.

Advantageously, at least one, preferably two further rotational pulley parts or redirecting rotational pulley parts (which may be formed like the transmission rotational pulley parts) are mounted on the centre frame by equal or similar mechanical connections as mentioned above. The redirecting rotational pulley parts are preferably mounted on opposite sides of an upper rod or along an upper dimension of the centre frame (in particular a part of the centre frame which is close to the upper end of the steering part). The redirecting rotational pulley parts are preferably mounted on a side of the main frame which is in the half of the centre frame opposite to that half in which the transmission rotational pulley parts are located. These two halves of the centre frame may be delimited by the steering pivot and/or the longitudinal direction of the steering part in neutral position. Preferably, the axes of the redirecting rotational pulley parts (i.e. their pivots or redirecting pivots, respectively) have the same distance as the transmission pivots from the steering part when it is in neutral position. Therefore, both the transmission pivots and the axes of the redirecting rotational pulley parts, in particular redirecting pivots may lie on a straight line parallel to the longitudinal extension of the steering part when the latter is in neutral position. Other positions may be envisaged, they may necessitate adapting the overall geometry of the pulley system, though. The pulling parts are also guided around the redirecting rotational pulley parts which are thus located in the run of the pulling parts between the ends attached to the traction parts and the transmission rotational pulley parts.

The axes of the rotational pulley parts, in particular the location of the transmission pivots are preferably configured to be located at equal distance to the steering pivot and the location at which the pulling part running around the respective rotational pulley part is attached to the steering device. This supports a simple design and easy calculation of the dimension of the pulling parts. However, other locations of the transmission pivots may be envisaged when the position of the redirecting pivots is adapted.

The traction parts may have the form of actuation levers (which may in the framework of this invention also be denoted as actuators) which are pivoted advantageously on the centre rail in a manner equal or similar to the pivoting of the steering part and/or the transmission levers. The traction parts may also have the form of a direct connection (e.g. by wire) between a bell crank lever connected to the aileron (e.g. by wire) and the pulling part. The advantage of employing an actuation lever in favour of a direct wire connection is that a reset of the aileron is supported when moving the steering part from a left or right position to its neutral position if actuation levers are used. The actuation levers are pivoted preferably at each outer end or in an outer end region of the centre rail. The actuation levers also extend to two sides of the centre rail, in particular below and above the centre rail and/or on two different sides of the centre rail. At both end regions of the actuation levers, force-transmitting means such as rods, wires or cables are fixedly attached (e.g. by screw connections) which establish a transfer of steering force (e.g. via bell crank levers) to the ailerons. Depending on the mechanical switching of the bell crank lever and its connection to the aileron, the aileron is deflected in an upward or a downward direction relative to the wing surface when the steering part is moved in a steering direction pointing to the respective aileron. It is however usual that the aileron is deflected in an upward direction since the actual flight direction shall be in analogy to the steering direction of the steering part.

The lower end or the lower end region, respectively, of the steering part is preferably fitted with tongues or nipples which may slide in grooves or slots of two different slip levers which run between the lower end or lower end region of the steering part and the lower end or lower end region of the actuation levers. If the steering part is moved to one side, the slip lever on the respective side will be pulled, thus again pulling the lower end of the actuation lever. Then again, the cable leading to the aileron will be pulled and the aileron deflected. If the steering part is moved back into the neutral position, or the anti-steering direction, respectively, the pulling part will pull on the upper end of the actuation lever and move it back into neutral position, thereby imposing a force in the anti-steering direction on the cable attached to the upper end of the actuation lever. Thereby, the active aileron is moved back into neutral position or deflected less, respectively.

Preferably, the actuation levers are connected in their lower regions with the lower parts of the transmission levers (i.e. the end region of the transmission levers which are opposite to the ends provided with the transmission rotational pulley parts) guiding the pulling part responsible for pulling the other actuation lever in an anti-steering direction. The connection is achieved by interconnecting rods. The interconnecting rods are attached to the actuation levers and the transmission levers preferably by a stable mechanical connection which allows for a relative motion between the interconnecting rod and the levers (such as a screw connection). This way, the rod may remain in a horizontal position or position parallel to a lower rim of the centre frame despite its movement. This allows for a continuous movement of the levers through different positions despite the linkage between them. A left actuation lever is thus mechanically connected to a right transmission lever and a right actuation lever is connected to a left transmission lever. If the steering part is moved in a steering direction, the transmission lever will be turned around its pivot such that its upper end rotates in the steering direction. Thereby, application of a steering force on the inactive aileron or the inactive actuation lever, respectively, is avoided by giving way of the respective transmission rotational pulley part to a pulling force of the pulling part.

Preferably, the aileron control system comprises a decoupling part for decoupling the steering part from an inactive aileron or inactive ailerons. The decoupling part advantageously includes the interconnecting rods and the transmission pivots. Decoupling in this context denotes the loosening (interruption) of a connection, in particular a fixed and/or stable mechanical connection by which a force, in particular a steering force applied to the steering part, is transferred from the steering part to the at least one active aileron. Thus, decoupling refers to interrupting a transmission of the steering force from the steering part to the active aileron. Even in a decoupled state, physical contact between potentially steering force- transmitting parts and inactive ailerons may persist or exist, respectively. In this case, the actuation lever on the side of the inactive aileron is decoupled by decreasing the strain on the respective pulling part due to a position change of the respective transmission rotational pulley part. In summary, the ailerons are selectively coupled to the steering part such that only the aileron in the steering direction is actuated in response to a steering impulse or a steering force, the other aileron or ailerons remaining in their neutral positions. Thus, also the steering force is selectively transmitted from the steering part to the active aileron.

The aileron control system further advantageously comprises a locking part and/or locking mechanism for locking an inactive actuation lever (i.e. an actuation lever which is connected to an inactive aileron). An inactive actuation lever in the framework of this invention denotes an actuation lever which is connected to the cables or wires leading to an inactive aileron. The locking part preferably comprises a support part such as a flat plate or a pin extending from a lower part of the centre frame. Such a part may be formed on both sides of the frame close to the inactive actuation lever which is to be locked. Preferably, the actuation levers are connected at their lower ends or lower end regions to the lower end region of the steering part by a second mechanical connection. This connection preferably comprises a kinking rod (i.e. a rod with a joint enabling a kink, such as a screw connection linking two parts of the rod). A longer part of the kinking rod may be connected to the actuation lever by a screw connection enabling a relative movement between the actuation lever and the kinking rod. A shorter part of the kinking rod having T-shape or comprising three longitudinal rod parts, respectively, may be connected to both a lower region of the centre frame and the lower end region of the steering part. The connection to the steering part may be accomplished by a spring rod. A spring rod may be constructed as a rod which runs in a guide part of the steering part, the guide part being attached to the steering part by a screw connection or a similar mechanical connection such that relative movement between the spring rod and the steering part is allowed for. A spring may be fitted around the spring rod and attached to an end plate of the spring rod, the end plate being located close to the short part of the kinking rod. If the actuation lever is actuated, the kinking rod is kinked and the spring is compressed by contact with the guide part. If steering force is now reduced, the spring load will push the actuation lever back into its neutral position, this setup thus having the effect of a reset part for the steering part and the aileron position. If the aileron is inactive (i.e. is to remain in its neutral position), the spring load has the effect that the kinking rod is pressed onto the support part. When being pressed down onto the support part, the kinking rod displays a small kink angle of preferably a few degrees, for example an angle between 2° and 3° and/or of 2° or 3°. It is important that the kink angle is other than 0° or other than approximately 0° to support a stable locking of the actuation lever. Such a stable locking prevents the actuation lever from being moved as long as no steering force is exerted on it. The spring and the spring rod thus serve as a reset part for bringing the steering part and the remainder of movable parts of the aileron control system into a neutral position and holding it there at least as long as no steering force is applied.

Advantageously, transfer of steering force between the steering part and the actuator levers may be achieved by a further mechanical connection such as a for example a guide rod for each side (left and right) which is located between the preferably lower end or lower end region of the actuators and a lower end or lower end region of the steering part such that advantageously a maximum of leverage is provided for steering. The lower end or lower end region of the steering part may be coupled to the guide rod through a pin which runs in a hollow part and/or a guide and/or a groove of the guide rod. Thereby, a steering movement of the steering part to one side will not apply any steering force to the guide rod and the actuator associated with the anti-steering direction. Rather, only the guide rod associated with the steering direction will be pulled by the steering part due to the pin abutting the closed end of the guide of the guide rod. A fixed mechanical connection between the guide rods and the actuator levers may be achieved for example by a form-fit or force-fit connection such as advantageously a screw connection which allows for a relative movement between the coupled guide rods and actuator levers. When the steering part is moved out of its neutral position, the guide rod belonging to the steering direction is thus moved or pulled, respectively, and pulls on the lower part of the associated actuator lever which then actuates or deflects e.g. via a cable or wire connection and a bell crank lever the active aileron.

The aileron control system according to the present invention may be used in any aircraft, in particular fixed-wing aircraft such as general aviation aircraft and/or ultra light aircraft and/or aircraft models and/or gliders. A certain embodiment of the invention may also be used in model aircraft (e.g. remote-controlled model aircraft). Thus, an aircraft comprising the above- described aileron control system is also part of the invention.

A method of controlling an aileron is described as a further part of the invention. Preferably, controlling the aileron comprises the use of only mechanical parts of an aileron control system. Advantageously, only an active aileron is selectively coupled to a steering part, an inactive aileron or inactive ailerons remaining in their neutral positions. Thereby, a steering force from a steering part is mechanically and selectively transmitted to a subset of ailerons out of a plurality of ailerons.

Advantageously, the active aileron or the active ailerons is an aileron or are ailerons which are located on the wing on the inner side of a curve or a rolling manoeuvre through which a aircraft is meant to pass. Thus, a corresponding method of controlling an aircraft also is part of the invention.

Furthermore, inactive ailerons may be locked and/or arrested in their neutral position both when an active aileron is actuated and when no steering force, in particular no lateral steering force such as a left or right steering force is exerted on the inactive aileron and the inactive aileron remains in its neutral position.

The invention is described in more detail in conjunction with the following figures: Figure 1 shows a first embodiment of the invention for employment in model aircraft. Figure 2 shows an explosion view of a second embodiment of the invention. Figure 3 shows a second embodiment of the invention in a neutral position. Figure 4 shows a second embodiment of the invention in a steering position. Figure 5 shows a relaxation process in the second embodiment. Figure 6 is a view of the second embodiment when fitted into a cockpit.

Figure 1 shows a first embodiment of the aileron control system 100 in accordance with the invention which may be used in particular in model aircraft. However, also use in ultra light or other small fixed-wing aircraft may be envisaged.

A steering device formed as a sledge 106 may be guided by guiding rod 107 such that sledge 106 and/or its guiding part 106a glides or slides, respectively, on guiding rod 107. Fixedly attached to sledge 106 is an actuator or traction part formed as an actuator loop 108. Engaged into the actuator loop 108 are pull cables 109, 115 which have ends formed as open loops. The dimensions of actuator loop 108 are such that in neutral position no contact is made between pull cables 109, 115 and actuator loop 108 or at least no steering forces are exerted by actuator loop 108 onto pull cables 109, 115. Once sledge 106 is moved out of the neutral position into a steering direction A, contact is made between actuator loop 108 and the pull cable 109, 115 which is located on the opposite side of the setup of wings 101, 102. In order to support the identity of steering direction and movement direction of sledge 106, a mechanical device which converts movement directions may be coupled between a user (or a motor, such as an electric steering motor for model aircraft) and sledge 106. The respective pull cables 109, 115 will then pull (by movement in direction A) kink rods 110, 111 out of its neutral position which is fixed by spring 113. During steering, spring 113 is thus expanded and/or loaded. Kink rods 110, 111 may be kinked at the location of joints 112 which may comprise a screw connection loose enough for allowing relative movement of rods 110, 111. Aileron cable 114 will then deflect active aileron 105 into an upward position by pulling in direction B. The degree of deflection depends on how far sledge 106 is moved out of the neutral position and/or how far pull cable 109, 115 is pulled.

Since during the above-described operation no contact is made between the other pull cable (in the case shown, pull cable 109) and actuator loop 108, inactive aileron 104 remains inactive. Rest plates 103 are designed to support ailerons 104, 105 when they are in a neutral position. Once sledge 106 is moved back from the steering position in the direction of the neutral position, spring 113 will pull kink rod 110, 111 back into a neutral position, thereby reducing strain on aileron cable 114 which will allow activeaileron 105 to go back into neutral position supported by gravity and/or air drag on aileron 105.

Figure 2 depicts an explosion view of the aileron control system according to a second embodiment. The second embodiment describes an integral aileron control system 300 which may be embedded as a kit into an aircraft. No additional modifications will be necessary on the aircraft into which the kit is embedded besides for example providing holding or attaching parts, respectively, for holding or attaching the kit in or to a preferably structural part of the aircraft, respectively, in particular in or to its airframe and/or fuselage. A centre frame 302 serves as a main frame for the kit and as a support for all other parts of the aileron control system 300. A centre rail 303 comprises two sandwich walls 303a, 303b which are attached to the front and the back of the centre frame 302 by a fixed mechanical connection, e.g. by an adhesive bond or a force and/or form fit connection (such as a screw connection). The centre rail 303 provides the pivots for the actuator levers 305, the transmission levers 306 and the joystick 301 which are advantageously all sandwiched by the sandwich walls 303 a, 303b and are preferably mechanically coupled to the centre rail 303 through screw connections along axes (especially flexing axes or swinging axes 309, 310, 316) which allow for a relative movement between the transmission levers 306, the actuation levers 305, the joystick 301 and the centre rail 303. The sandwich walls 303a, 303b are held together by support rails 303c, 303d which run in the longitudinal direction of the sandwich walls 303a, 303b and are preferably inserted into end pieces 304b of the embedding tongue 304.

Preferably at the outer ends of the centre rail 303 are attached the embedding parts 304 which may take the form of a tongue or a screw (in particular, an embedding screw) 304a inserted into advantageously end pieces or screw thread parts 304b which again are sandwiched by the centre rail 303 or enclose a circumference of the centre rail 303 and may be fixed to the centre rail 303 by another screw connection. The transmission levers 306 are sandwiched by the centre rail 303 inside the circumference of the centre frame 302, the actuation levers 305 being preferably located between the sandwich walls 303 a, 303b near an outer end of the centre rail 303. The sandwich walls 303a, 303b may be held together by the embedding part 304 and two holding rails 303 c, 303 d. Preferably at an upper end of the transmission lever 306 is located a transmission cogwheel 307. At the vertical centre line of the centre frame 302, the joystick 301 is fed through an opening between the sandwich walls 303a, 303b. The joystick 301 preferably swings on a screw connection along a flexing axis 309, the screw being inserted through both sandwich walls 303a, 303b and the joystick 301. At a location of the joystick which is above the pulley wheel pivot axis 311 , a pulling part formed by a chain is fixedly attached to the joystick 301. The chain 303 is led around the cogwheel 307 and a redirecting cogwheel 308 which is located preferably at an upper rim of the centre frame 302 and on the other side of the vertical centre line or the longitudinal axis of the joystick 301 when viewed from the position of the cogwheel 307. The chain 303 is then laid back onto the side of transmission cogwheel 307 and coupled to the actuation lever 305 by a pull rod 301. A corresponding setup is located on the reverse front of the centre frame 302, the chain 303 however being coupled by a pull rod 314 to an actuation lever 305 which is associated with the other steering direction.

A locking or arresting mechanism is located at the lower region of the centre frame 302 and comprises a kinking rod with a longer part 309, a shorter part 320 and a kinking joint 321 as well as a abutment or locking plate 322 which is designed for abutting against the joint 321 or the neighbouring parts of longer part 319 and/or shorter part 320. The longer part 319 is preferably mechanically coupled to the actuator lever 305 by a screw connection along a flexing access 330 and the shorter part is preferably coupled to the lower region of the centre frame 302 by equivalent mechanical connection which allows for relative movement between the shorter part 320 and the centre frame 302. The locking plate 322 is advantageously located below any possible and/or envisaged position of the kinking rod. When the kinking rod abuts the locking plate 322, an angle α between the longitudinal axes of the longer part 319 and the shorter part 320 preferably measures a few degrees, more preferably between 2 ° (degrees) or 3 ° (degrees) or about 2 ° (degrees). It is preferable that the angle α at least is not equal to 0 ° (degrees). The shorter part 322 of the kinking rod is advantageously laid out in T-form such that at an additional lever part of the shorter part 320 a spring rod 324 may be attached by a mechanical connection such as a screw connection which allows for relative movement between the shorter part 320 and a spring rod 324. An actuator end plate may be located around the spring rod 324 between the connection to the shorter part 320 and the opposite end of the spring rod 324. A steering end plate 307 is preferably located around the spring rod 324 at an end region of the spring rod 324 which is inserted into a spring rod guide 326, spring rod guide 326 may take the form of two opposite plates with each a hole for guiding the spring rod 324. The spring rod guide 326 is attached to a lower end region of the joystick 301 such that a movement of the joystick 301 in a steering direction will compress the spring or locking spring 325, respectively, located around the spring rod 324 between the end plates 307 and 308 which is located on the other side, i.e. the side of the aileron control system 300 pointing towards the anti-steering direction. A corresponding setup is located at the reverse front of the centre frame 302 and mirrored with regard to the longitudinal axis of the joystick 301. A further advantage of the locking mechanism is that flying the aircraft on its back becomes possible without having the ailerons 104, 105 deflect due to gravity. The spring load of a spring mechanism or the springs 325, respectively, act in a direction contrary to the direction of gravity when the aircraft is flown on its back such that a deflection of ailerons 104, 105 without applying a steering force is inhibited or avoided, respectively. Thereby, involuntary deflection (i.e. a deflection which is not anticipated and/or desired by e.g. the human operator) of the ailerons 104, 105 is inhibited.

Furthermore, the lower end region of the joystick 301 comprises a pin 334 which protrudes preferably vertically out of the front and rear surfaces of the joystick 301 and may be inserted into steering part guides 323 of guide rods 333. The guide rods 333 are connected by a mechanical connection preferably comprising a screw connection along a flexing axis 330 to the actuator levers 305 which allows for relative movement between a guide rod 333 and an actuator lever 305. Corresponding guide rods and connections are again located on both frontal sides of the centre frame 302 while being preferably mirrored with regard to the longitudinal axis of the joystick 301. It is to be noted that the locking mechanism is located on a different lateral side of the centre frame 302 than the guide rod 333, i.e. if the locking mechanism is located on the left side of the centre frame 302, the guide rod 333 shall be located on the right side. On the other frontal side of the main frame 302, the locking mechanism is located at the rear of the guide rod 333 first described, and the guide rod 333 is located at the rear of the locking mechanism first described.

Interconnecting rods 317 are coupled between the lower end regions of the transmission levers 306 and the actuator levers 305, mechanical connections between the respective parts being achieved preferably by screw connections 318a, 318b which allow for relative movement as a connector part.

Figure 3 shows a frontal view of the aileron control system 300 according to the second embodiment in a neutral steering position. The neutral steering position in particular denotes a position of the joystick 301 which does not exert any steering forces on other parts of the aileron control system 300.

Aileron cables 331 and 332 are attached to the actuator levers 305 preferably at both end regions of each actuator lever 305. The aileron cables 331, 332 are designed for pulling on a belt crank lever or an equivalent mechanical device for moving an aileron, in particular an active aileron.

Figure 4 is a view of the aileron system 300 according to the second embodiment when a left steering force is applied. Joystick 301 is moved in left steering direction C, thus pulling on guide rod 333 which is connected to the left aileron. Consequently, the left actuator lever 305 is pulled at its lower part to the centre of the aileron control system 300 and exerts a force on the corresponding aileron cable 331 for deflecting the aileron. The locking mechanism is also pulled to the centre of the aileron system 300, thus unlocking the left actuator lever 305. By movement of the actuator 305, interconnecting rod 317 on the backside of the centre frame 302 as shown in Figure 4 is pushed in direction E to the centre of the aileron control system 300, thus tilting the right transmission lever 306 such that the cogwheel 307 attached to that transmission lever 306 is tilted towards the joystick 301, thereby setting free a certain length of the pulley chain 313 on the backside of the centre frame 302. Thus, the force is reduced or eliminated which would be exerted by joystick 301 on that pulley chain 313 if the corresponding transmission cogwheel 307 did not change its position to the centre of the aileron control system 300. The stress applied to pulley chain 313 is reduced or no stress is applied to it, respectively. In consequence, no steering force is applied to the right actuator lever 305 which thus remains in its neutral position. Since pulley chain 313 may be seen as a (direct) extension of aileron cables 331, 332, no force is then exerted onto the inactive ailerons. The other chain 313 is pulled by the connection to actuator lever 305 into directions D and F, the necessary chain length being set free by the left steering movement of the joystick 301. Consequently, the mechanism of cogwheels 307, 308 and transmission levers 306 also serves as a compensation part which compensates a movement of joystick 301 in a steering direction, such that parts of the aileron control system associated with the anti- steering direction are not actuated in response to the movement of joystick 301.

As shown in Figure 5, a movement of the joystick back into the direction G of the neutral position, will reverse the movement of the pulley chain 313 coupled to the left actuator lever 305 in directions H, L and K while turning the redirection cogwheel 308 and the transmission cogwheel 307 in a clockwise direction. The transmission cogwheel 307 which changed its position due to the left steering movement is brought back into the neutral position by the reverse movement of the left actuator lever 305 and the interconnecting rod 317. The load of spring 324 assists in moving the joystick 301 back into a neutral position, the locking mechanism, in particular the longer part 309 and the shorter part 320 as well as the joint 310 of the kinking rod is pushed down again and abut against the locking plate 322. The reverse movement of the chain 313 coupled to the left actuator 305 pulls the left actuator 305 back into neutral position. Figure 6 is a view of the aileron control system 300 according to the second embodiment when embedded or built-in to an aircraft cockpit 600. The embedding tongues 304 comprises screw thread parts 304a and screws 304b which are inserted partly into the screw thread parts 304a. Screws 304b are inserted to both lateral sides of the aileron control system 300 into corresponding parts of the airframe 601 which allow for a stable mechanical connection to the airframe 601. Preferably, the aileron control system 300 may be rotated and/or swung in a front and back direction along an axis in the longitudinal direction of centre rail 303 in order to apply a steering force to the elevator cable 602 for steering the elevator.

The aileron cables 331 and 332 are attached to the actuator levers 305 and lead through aileron cable channels 603 to the ailerons. The elevator cables 602 are attached to the elevator cable 309 preferably located to lower parts of the centre frame 302, in particular below the end position of the joystick 301.

List of reference signs

100 aileron control system

101, 102 wings

103 support plates

104 inactive aileron

105 active aileron

106 sledge

106a guiding part

107 guiding rod

108 actuator loop

109 pull cable

110 part of kink rod

111 part of kink rod

112 joint

113 spring

114 aileron cable

115 aileron cable

300 aileron control system

301 joystick

302 centre frame

303 centre rail

303a, 303b sandwich walls of centre rail 303

303c, 303d support rails

304 embedding tongue

304a embedding screw

304b screw thread part

305 actuator lever

306 transmission lever

307 transmission pulley wheel

308 redirection pulley wheel

309 steering pivot

310 transmission pivot

311 transmission pulley wheel axis 312 redirection pulley wheel axis

313 pulley chain

314 pull rod

315 flexing axis between actuator lever 305 and pull rod 314

316 pivot of actuator lever 305

317 interconnecting rod

318a flexing axis between interconnecting rod 317 and actuator lever 305

318b flexing axis between interconnecting rod 317 and transmission lever 306

319 longer part of kinking rod

320 shorter part of kinking rod

321 kinking joint

322 locking plate

323 steering part guide

324 spring rod

325 locking spring

326 spring rod guide

327 actuator end plate

328 steering end plate

329 elevator connecting loop

330 flexing axis between guide rod 334 and actuator lever 305

331 lower aileron cable

332 upper aileron cable

333 guide rod

334 steering pin

600 aircraft cockpit

601 airframe

602 elevator cables

603 aileron cable channel

A, B, C, D, E, F,

G, H , I, K, L, M movement directions

Claims

1. Aileron control system (100, 300) comprising a coupling mechanism (108, 109, 313, 107, 333, 334; 305, 306, 313, 323, 333, 334) for mechanically and selectively transmitting a steering force from a steering part (106, 301) to a subset of ailerons (105) out of a plurality of ailerons (104, 105).

2. The aileron control system (100, 300) according to the previous claim characterised by a decoupling part (317, 306, 313) for decoupling the steering part (106, 301) from an inactive aileron (104).

3. The aileron control system (100, 300) according to any one of the previous claims characterised by a locking part (111, 110, 112, 322, 324, 113, 106a; 319, 320, 321, 322, 324, 325, 326) for locking an inactive aileron (104).

4. The aileron control system (100, 300) according to the previous claim, wherein the locking part (111, 110, 112, 322, 324, 113, 106a; 319, 320, 321, 322, 324, 325, 326) comprises a spring mechanism (324, 325, 326) for inhibiting involuntary deflection of an aileron (104, 105).

5. The aileron control system (100, 300) according to any one of the previous claims characterised by an embedding part (304) for embedding the aileron control system (100, 300) into an aircraft.

6. The aileron control system (100, 300) according to any one of the previous claims characterised by a pulling part (313) for transferring a steering force from the steering part (106, 301) to the active aileron (105).

7. The aileron control system (100, 300) according to the previous claim characterised by a pulley system (307, 308, 313) comprising at least two rotational pulley parts (307) and at least two pulling parts (313).

8. The aileron control system (100, 300) according to the previous claim characterised in that the axis (311) of at least one rotational pulley part (307) is configured to be located at equal distance to a pivot (309) of the steering part (106, 301) and a location at which a pulling part (313) is attached to the steering device (301).

9. The aileron control system (100, 300) according to any one of the previous claims characterised by a reset part (113, 324; 324, 325) for resetting an actuated aileron (105).

10. The aileron control system (100, 300) according to any one of the previous claims characterised by a compensation part (109, 307, 313, 317; 306, 307, 313, 317) for compensating a movement of the steering part (106, 301).

11. Aircraft comprising an aileron control system (100, 300) according to any one of the previous claims.

12. A method of controlling an aileron wherein a steering force from a steering part (106, 301) is mechanically and selectively transmitted to a subset of ailerons (105) out of a plurality of ailerons (104, 105).

13. A method of controlling an aircraft comprising the method of claim 11 characterised in that only an aileron (105) on the inner side of a curve through which an aircraft is meant to pass is actuated.

14. The method according to any one of the two previous claims characterised in that an inactive aileron (104) is locked.