DE7802077U1 - TAILLESS PLANE - Google Patents

Description

The innovation concerns a tailless aircraft with elliptical wings or approximated by rectangles and / or trapezoids elliptical wings. In particular, it also relates to flying wing aircraft that do not have a vertical tail unit and no horizontal stabilizer, i.e. no vertical and horizontal stabilization surfaces.

The tailless aircraft to which the innovation relates, can be both gliders and powered airplanes. There are also none for the type of construction Restrictions. For example, the wings can be in open or closed timber construction, in rib construction, with or without a spar, as a planked hard foam core or Made of full glass fiber reinforced plastic with self-supporting Wing shells with or without spar, made of deep-drawn, pressed or injection-molded wing shells made of thermoplastic or duroplastic Be made of plastics. Although the innovation is preferably applicable to model airplanes, exist no difficulties or restrictions, the innovation too

apply to manned aircraft.

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Since a tailless aircraft does not have a separate horizontal stabilizer, the profiles and wing outlines of a tailless aircraft must be given special careful consideration be selected for the creation of stability. On the other hand, compromises always have to be accepted when building aircraft because, for example, every outline shape in construction, in aerodynamics / in flight mechanics and in statics is and has disadvantages. It is known, for example, that with a so-called "elliptical wing" a favorable reduction

x reduction of the induced drag is achieved. An "elliptical wing" or wing with an "elliptical profile" is a wing outline in which the application of the product of the local lift coefficient (C _A ) and the local depth (t) over the half-span of the wing takes the form of a quarter-ellipse supplies. Further details on these calculations can be found, for example, in "Aerodynamics of pure subsonic flow" by F. Dubs. However, since the construction of a purely elliptical wing poses great structural difficulties and the production of wings with such outlines is very expensive, it has proven to be advantageous and customary to use a trapezoid, a double trapezoid, several trapezoids or a combination of a rectangle and a or

) to approximate several trapezoids. In particular, the double trapeze a good approximation of the elliptical profile and can be considered an optimum with regard to the construction difficulties, the sash weight, the damping of the tendency to tilt to the side, etc. with delivery of the lowest additional resistance. Calculations for this can be found, for example, in: "The influence of the aerodynamic design parameters on the performance of Gliders "by Professor E. Thomas, published in Aerocurier. In the case of a double trapezoidal or rectangular-trapezoidal profile, which approximates an elliptical profile, is essentially the elliptical surface equal to the area approximated by trapezoids and rectangles.

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It is now known to design tailless plug tools in such a way that that they have a high flight performance, i.e., for example, in a speed range low rate of descent and have a large glide ratio, or on the other hand to be designed so that they have the highest possible flight stability. So For example, for stable flight, a more or less strong twisting of the wing in wing ground plans with a sweep or the use of profiles with a positive moment coefficient be necessary with weak or non-swept wing ground plans, while on the other hand, high flight performance is more likely to be necessary straight wings without sweep and with high aspect ratio can be achieved.

It is therefore the object of the invention to create a brushless aircraft with high stability, which nevertheless has high flight performance achieved. The wing geometry should still be simple despite its delivery of the highest degree of flight stability allow good approximation of the elliptical wing.

This task is accomplished by a tailless aircraft of the type described above Type solved in which the local wing depth in each case on the fuselage side over at least 10% of the length of the wing half-span is enlarged compared to the local depth corresponding to the elliptical profile, the strongest Widening is more than 10% and the wing area widened in this way essentially steadily into the rest of the exact area or approximated elliptical profile passes.

The surface depth thus increased on the fuselage side according to the invention the wing provides high flight stability. On the other hand, as stated above, the product of the local buoyancy s coefficient and the local depth is decisive for the elliptical curve shape or its linear approximations by increasing the local surface depth, profiles with lower local lift coefficients are used, whereby nevertheless the product from the local surface depth and approximately the

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corresponds to elliptical lift distribution. In particular, it is possible to use airfoil profiles that have both enable high flight performance as well as great flight stability.

It is particularly preferred that the length of the widened airfoil area be 10 to 50% of the half span. An even more preferred range is 25 to 30% of the half span.

It has also proven to be beneficial, the wing depth at the point of greatest widening about 110 to about 180%, preferably 120 to 150%, of the locally corresponding equivalent theoretical ellipse depth.

Particularly optimal flight performance is achieved in these areas with high flight stability.

It is still beneficial to have the area of greatest widening to be arranged in each case directly near the fuselage. The wing thus receives its greatest depth at its point of attachment Hull.

In tailless aircraft, the wings are often designed in the shape of an arrow, as the arrow shape is connected, among other things allows a certain flight stability with a twist. On the other hand, there are often less favorable lift distributions than have to be accepted with an equal-sized, unswept wing, it is particularly desirable also to stabilize such a "swept" aircraft. Therefore, a particular embodiment of the invention is that in a tailless aircraft with positive or negative swept wings up to about 10 positive or negative Sweep the respective local wing depth on the fuselage side over at least 10% of the length of the wing half-span compared to the corresponding swept elliptical profile corresponding local depth is enlarged, the

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strongest broadening is also more than 10%. Here, the term "arrow" is used in general Meaning used: namely, there is no arrow when the t / 4 line (i.e. the line that connects those points with each other connects, which is measured at 25% of the local wing depth from the edge of the nose) runs at right angles to the longitudinal axis of the aircraft; the arrow is positive when the The t / 4 line is at an acute angle to the longitudinal axis of the aircraft and the arrow is negative if the t / 4 line runs forward at an acute angle to the longitudinal axis of the aircraft.

In any case, any arrow that is present is given by the invention Widening of the wing close to the fuselage of the aircraft ^ a remarkably increased stability. Predominantly the rotation of the aircraft around the transverse axis is stabilized here.

C On tailless aircraft, usually the elevator is

f and the aileron combined in one flap at the end of the wing

intended. The ailerons prevent or serve to turn around

the longitudinal axis and are opposed to rotation about the longitudinal axis; set knocked out. Should the flaps be used as elevators, however

. to prevent rotation or to rotate around the transverse axis

are used, the two flaps are either both moved up or both down. Now with the tailless one Aircraft according to the invention, the stability against rotation around the transverse axis essentially in the middle area of the flight equipment, i.e. near the fuselage, it has proven to be useful to use the flaps to control the position around the transverse axis relocate to this area as well. Therefore, after a pre-

ferred embodiment of the invention, the elevator independently

j; provided by the aileron as a second flap on the wing near the fuselage, so that the aircraft has a total of four flaps, namely two ailerons and two elevators.

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These independent elevators further improve stability and flight performance during flight maneuvers.

Studies on the airfoil profiles have shown that the tailless aircraft according to the invention preferably has wing cross-sections which are laminar profiles.

Particularly preferred are wing cross-sections, the laminar profiles with "S-lay" are and preferably have positive moment coefficients.

A particularly advantageous laminar profile is, for example FX O5-H-126 developed by F.X. Viortmann in "Experimental Investigations on new laminar profiles for gliders and helicopter "described in newspaper for flight science 1957 is.

For the modification in a laminar profile with S-lay has in particular the profile FX 62-K-131/17 proved to be advantageous, that of D. Althaus in the Stuttgart profile catalog (Techn. University of Stuttgart, self-published).

It is particularly useful to choose laminar profiles that have a positive moment coefficient, since profiles with a positive moment coefficient largely have a righting force Experienced. The position of the pressure point moves forward with increasing speed, and if the pressure point is in front of The center of gravity is, the force has a straightening effect, so that returning moments result and thus overall a stable one Flight behavior.

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Another improvement of the aircraft according to the invention, whose wing cross-sections are laminar profiles, consists in that the wings at their rear end each have auxiliary wings that rearward over the trailing edge of the wing protrude and are attached to the wing, leaving an air gap between the wing and auxiliary wing.

The air flowing under the wing flows to the largest Part through the gap between the wing and the auxiliary wing, while the remaining part of this flow together with additional air flows under the auxiliary wing. This creates additional lift on the auxiliary wing. Overall it will on the one hand, the flow around the wing is stabilized and, on the other hand, the flight stability is increased overall.

In a particularly preferred embodiment, the auxiliary wing is adjustable attached to the wing.

Advantageous adjustment options for the auxiliary wing are, on the one hand, a rotation of the auxiliary wing about its attachment point on the bracket that connects it to the wing, and / or on the other hand, a displacement of the auxiliary wing in the direction of Wing depth forward or aft.

With model airplanes it will be in view of the construction difficulties however, it generally proves to be expedient to provide a fixed bracket between the auxiliary wing and the wing, the optimal flow conditions with particularly preferred speed ranges for the aircraft and desired angles of attack is adapted.

By attaching an auxiliary wing to the wing, the flow conditions at the trailing edge of the wing be optimized in such a way that wings with laminar profiles can be used without an S-shaped profile outlet. Since the The trailing edge of a wing, which is elongated towards the S-profile outlet, is usually relatively thin, so that the flaps are difficult to open can be attached and are also relatively unstable, this has the advantage of having the flaps on a laminar profile without an S-shaped

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To make the profile outlet mechanically more stable. Of particular note is still that by this arrangement of auxiliary wings behind or under the actual wing profile an additional improvement in flight stability and flight performance is achieved.

In general, with regard to the selection and modification of the profiles, it should be noted that from the "Stuttgarter Profilkatalog" (Technical University of Stuttgart, self-published) Laminar profiles with a negative moment coefficient can be selected can be suitably improved by attaching auxiliary wings. On the other hand, conventional laminar profiles can also be used are selected, which are designed by modifying the profile run-out in such a way that the profile is positive Receives moment coefficients or at least becomes pressure point fixed.

If you want to move from the trimmed normal position to higher or lower flight speeds, the position of the pressure point changes relative to the center of gravity. In order to compensate for the resulting lift moments, the moment coefficient must be set by positive or negative flaps- >. can be adapted to the new desired flight speed. In the case of flap deflections for the area of the slightest sink, an additional wing restriction occurs in the area of the elevator flap, whereby the product of the wing depth times the local lift coefficient is even better adapted to the equivalent value of the elliptical wing, so that in;. Area of the greatest induced resistance optimal values | be achieved and therefore very good sink rate of \ aircraft.

On the other hand, positive elevator deflections to achieve higher flight speeds both cause a reduction the positive moment coefficients and thus a reduction in flight stability in high-speed flight as well as an increase the total drag caused by the flap deflections and the then less favorable elliptical lift distribution.

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Another embodiment of the invention therefore provides not to achieve the change in torque to achieve another higher airspeed by flap deflections, but by shifting the center of gravity to the position of the pressure point position suitable for the desired speed.

Result, both the flight stability at higher speeds remains _λ speeds always positive and the induced cons-V was as small as possible. There is also no increase in the total resistance due to positive valve deflections. This shift in the center of gravity therefore significantly improves flight performance over the entire speed range.

In order to effect a correction of the center of gravity, according to a further embodiment of the invention inside the Aircraft ballast moved to shift the center of gravity. § In particular, a device for shifting ballast is in the

* Inside the aircraft, preferably inside the fuselage,

Ί provided.

Depending on the type; of the ballast to be moved is the Device designed differently. For example, aircraft-internal drive, control and regulating devices can be used as ballast.

directions are shifted. Because these are already within des Flugzeuqs existing devices moved as ballast inserting additional weights can be avoided.

In model airplanes, the mentioned propulsion, Control and / or regulating devices, preferably mounted on a slide, by means known per se, such as, for example Servomotors with corresponding transmission elements, such as racks, rubber wheel clutches, etc., is moved.

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- 10 In the case of manned aircraft, it is also possible to use the

Move pilot seat with the pilot. Devices for moving seats are well known, usually the seat is provided in its lower part with runner-like lugs that move in rails. With other displacement devices rollers run in rails. Such devices and the necessary adjustment options are known per se to the person skilled in the art and need not be elaborated further here.

If the aircraft weight allows it, external ballast can also be carried and be moved. All of these types of ballast can be relocated or moved either individually or in combination will,

However, there is the even and continuous controlled movement of solid objects requires the use of relatively expensive precision equipment and, moreover, the displacement of control and drive devices, which are necessary for the operation of the aircraft, with the risk of faulty Working of these devices is connected, it is preferred according to a further advantageous embodiment of the invention, that liquid volumes are shifted between tanks. By attaching liquid tanks, the location of the center of gravity can be determined easily and precisely. For example, by pumping the liquid from one tank to another the center of gravity shifted evenly and continuously in a simple manner. In this case, means known per se, such as liquid pumps, which are controlled by the pilot by hand or, in the case of model airplanes, remotely, the liquid from one or more tanks pump into another or several others.

The center of gravity is shifted forward to achieve high flight speeds. This reduces the angle of attack and corrected so that high speed ranges can be achieved. This makes it possible to achieve particularly high high-speed flight performance to achieve with high stability. In addition, the various speed ranges lose their influence

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on flight stability.

The possibility of shifting the center of gravity can also be used to advantage during take-off and landing. When For example, the airspeed for landing is greatly reduced by moving the center of gravity backwards correcting the position of the aircraft and increasing stability.

The devices for shifting the center of gravity are therefore special Can be used with advantage in tailless or flying wing aircraft, as the stabilization is provided by conventional tail units partially or completely omitted. Even if the tailless aircraft according to the present invention by the wing extension already has improved stability near the fuselage, so it is but the additional improvement in stability is of great advantage.

With gliders there is a common type of take-off in that the airplane is pulled up with the help of a long line. The release device for manned gliders or The high-start hook on model gliders is generally at an angle of about 30 ° in front of the center of gravity on the underside of the runipf attached. In the case of a tailless aircraft, especially a flying wing aircraft, the damping and stabilizing effect If the tail unit is missing, the device is the device in a tailless aircraft designed as a glider according to the present invention for pulling up the aircraft, preferably in the form of two release devices or two high-start hooks Models formed, each symmetrical on both sides of the longitudinal axis and each with a short distance from the overall center of gravity are arranged.

It is particularly preferred that the two release devices or high-start hooks each at the point under a wing are arranged near the fuselage, which is approximately the smallest distance to the

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Overall focus. Short distances to the Overall center of gravity observed in both the vertical and the horizontal plane. The two fastening devices for the upper end of the high take-off line are therefore each on one wing half near the fuselage, so that a results in the smallest possible distance to the overall center of gravity. By the double design and the described arrangement of the fastening device a safe pulling up is guaranteed for the upper end of the line. The stability of the tailless Airplane will pull up compared to that conventionally simple fastening device noticeably increased. In particular, rotations around the longitudinal axis and around the vertical axis of the aircraft is greatly reduced due to the double design of the fastening device.

To achieve a good seal of the wing / fuselage transition it proves to be advantageous to attach the wing to its fuselage side To provide the end with a projecting lug extending along the wing chord, which is inserted into a groove fits in the fuselage and engages in this, the shape of which corresponds to the approach shape so exactly that the wing through this fit can be used adjusted with respect to the fuselage. The attachment of the wing by means of such a trained Approach in a groove in the fuselage is preferably designed to be detachable. For smaller model airplanes that can no longer be dismantled are to be, a permanent attachment, for example by gluing, is also possible.

For a releasable fastening of the approach in the groove, fastening devices known per se, such as, for example, can be used Bolts, can be used.

The length of the approach on the wing is preferably as possible chosen large in order to achieve a good, tight fit. On the other hand, in a tailless aircraft with the inventive Widening of the wing near the fuselage that

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Elevator according to a particular embodiment of the invention is provided separately from the aileron on the trailing edge of the wing near the fuselage, in this case the length of the Approach limited, as the elevator must remain movable.

In the case of larger model aircraft, it is preferable for the wing to be attached to the fuselage by means of additional strips or struts is attached, which extend from the interior of the wing to the interior of the fuselage and also by means of Usual fasteners, such as bolts, screws, snaps, split pins, etc. are fastened inside the fuselage. Through this For large wing half-spans, a more secure attachment of the detachably attached wing to the fuselage is guaranteed, while the adjustment is essentially by approach and groove takes place.

The invention will now be explained in more detail by means of exemplary embodiments with reference to the accompanying drawings.

In the drawings show:

FIG. 1 shows a tailless aircraft according to the invention in plan view;

FIG. 2 shows the wing of a tailless aircraft of another embodiment of the invention with swept wings, also in plan view;

Figures 3 and 4 are cross sections through the wing in Figure 1 along the lines A-A and B-B (enlarged);

Figure 5 shows a preferred laminar for Nurflügelflugzeuge with S-lay, the positive Moi tentenbeiwert has;

FIG. 6 shows a cross-sectional view of a wing with a laminar profile in combination with an auxiliary wing;

FIG. 7 shows another embodiment of a tailless aircraft according to the invention with a separate elevator in plan view;

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FIG. 8 shows a side view of a model glider airplane with two high-start hooks according to the invention;

Figure 9 is a cross-sectional view of the aircraft according to Figure in a plane perpendicular to the longitudinal axis and through the Vertical axis;

FIG. 10 shows a section through the attachment point of a wing on the fuselage in a model airplane Airplane according to the invention in elevation and

FIG. 11 shows a section through the attachment point of a wing on the fuselage, which is shown in FIG Top view.

The tailless model airplane shown in FIG. 1 has hydrofoils 1 in which an elliptical profile _{is approximated by two trapezoids T 1} and T ″. In the area of the fuselage-side trapezoid T. the wing depth t is locally increased over more than 10% of the half-span H by more than 10% of the local depth (or depth of the trapezoid T ..) corresponding to the elliptical profile. Such a widening extends up to part of the half-span, which is denoted ^{in Figure 1 with H} _Verqr.

Due to the increased wing depths in the fuselage area, the tailless aircraft shown in FIG. 1 has better stability than a conventional aircraft whose wing outline is given by the double trapezoid T ₁ , T ″.

In the example shown, the t / 4 line runs at a right angle to the longitudinal axis of the aircraft, so that the The aircraft has an arrow 0 overall.

In Figure 2, however, is the wing of a tailless aircraft shown in plan view, in which the elliptical profile

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is approximated by a rectangle R and a trapezoid T ^ and the has a negative arrow, as the t / 4 line runs forward at an acute angle to the longitudinal axis. According to the invention this wing is widened near the fuselage. the The cross-sections of the airfoils shown in FIGS. 3 and 4 along the lines A-A and B-B explain this broadening. On the outside of the wing, at section line B-B, that shown in Figure 4 is actual Airfoil profile equal to the profile that is related to V borrowed the chord for an unbroken wing. In Figure 3 is the actual profile according to section A-A compared to the profile, which corresponds to the wing depth of the conventional elliptical profile approximated by a rectangle R, widened. While the outer line corresponds to the actual airfoil profile, the profile that the Would correspond to a rectangle approximation, drawn inside. It can be seen that the wing chord t versus the depth t ,,, i.e. the equivalent depth of the elliptical profile or the approximation of the elliptical profile is enlarged by more than 10%.

/ The airfoil profile shown in Figure 4 is a laminar profile, whose profile outlet is modified to be S-shaped. The same profile is shown in Figure 3 on the wing cross-section A-A used. Slight modifications to the profile due to the sash curtain and the like, however, are possible and lie within the scope of the invention.

A particularly preferred profile for a flying wing aircraft is shown in FIG. Another preferred embodiment of such a profile is a modification of the profile FX 62-K-131/17, that of D. Althaus in the Stuttgart profile catalog loc. has been specified, which has an S-runout and a positive moment coefficient.

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Figure 6 shows a laminar profile as a cross section through one Wing of a tailless plug stuff according to the invention, on the trailing edge of which the profile of an auxiliary wing can be seen is. The auxiliary wing 2 is connected to the wing 1 via a bracket 3, leaving an air gap between the wing 1 and the auxiliary wing 2 connected.

Figure 7 shows another embodiment of a brushless · aircraft according to the invention in plan view. On the wings 1, which are widened in the fuselage area according to the invention, flaps serving as ailerons 4 are provided at the outer end, while additional elevators 5 are provided on the trailing edge of the wings in the widened area near the fuselage. These elevators are thus in,; located in the area that is essential to flight stability | contributes. |

Figure 8 shows a side view of a model airplane as a glider f trained aircraft according to the invention in a view

, from the wing tip approximately in the direction of the transverse axis of the aircraft |

on the fuselage 6. A high-start hook 7 is located on the;

Underside of the wing 1 at the smallest distance to (

Main emphasis. A line 8 that forks is with your i?

hung one end in this high-start hook 7. The other |

The end is covered by the body 6, below the other support |

flügelis 1 attached to the symmetrically corresponding point. '

FIG. 9 shows a reduced cross-sectional view of the aircraft according to FIG. 8 in a plane passing through the vertical axis and runs perpendicular to the longitudinal axis. The two high-start hooks 7 are each on the underside of the wing 1 in the shortest distance to the center of gravity.

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At appropriate places, manned gliders Notching devices may be provided.

Finally, FIG. 10 shows the attachment point of a wing 1 on the fuselage 6 in section as an elevation. The wing 1 is with a projection 9 is provided which extends in the direction of the depth of the wing. This approach has an end face Profile which is essentially the same as the hollow profile of a groove 10 in the fuselage. When inserting the approaches s 9 in the groove 10 is 'thereby the position of the wing 1 with respect to the fuselage 6 achieved. If the model airplane, for example dismantled for transport, is to be assembled, the Wing 1 with the extension 9 inserted into the groove 10 and by means of known fastening means such as bolts, Snapper, screws or the like attached. In the example shown, a bolt 11 was through the side wall of the

Groove, the projection 9 and the second side wall of the groove 10 pushed through.

A strut 12 which is fixed in the hull 6 and protrudes through an opening in the side wall of the groove 10, \ takes over the bending forces of the wing. 1

FIG. 11 shows a section through the attachment point of the hydrofoil on the fuselage according to Figure 10 in section in plan view. The approach 9 is pushed into the groove 10 and fastened by means of bolts. The length of the approach 9 extends approximately from the nose edge of the wing to the approach of a flap 5, which as Elevator is used. This flap is freely movable up and down.

Such a releasable attachment for wings of model airplanes on the fuselage provides excellent centering

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tion and adjustment of the wing, a fixed mounting of the wing on the fuselage. Especially when producing the The wing and the fuselage made of glass fiber reinforced plastic (GRP) is a precise coordination of the attachment profile on the groove profile possible.

7802077 06.Ό7.78 y

Claims (16)

1. Tailless aircraft with elliptical wings or elliptical wings approximated by rectangles and / or trapezoids, characterized in that the local wing depth is in each case on the fuselage side over at least 10% of the length of the wing half-span (H) compared to the local area corresponding to the elliptical profile Depth is increased, with the strongest broadening being more than 10% and that broadened in this way The wing area merges essentially steadily into the rest of the exact or approximate elliptical profile. 2. Aircraft according to claim 1, characterized in that the length of the widened airfoil region (H _Verbt) 10-50%, preferably 25 - 30% <j _e r is semi-span. 3. Aircraft according to claim 1 or 2, characterized in that the wing depth on the Place of greatest widening about 110 to about 180%, preferably 120 to 150% of the locally corresponding, equivalent theoretical ellipse depth. 4. Tail-less aircraft with positive or negative swept arrows Airfoils, characterized in that the respective local airfoil depth is equal to the corresponding local wing depth of the unswept The wing of the aircraft according to claim 1, 2 or 3 is. 7802077. 06.07.78 April 3, 1978 Dr.HS / DD PA - 2 Dieter Paff New pages 2 and 2a of the protection claims 5. Aircraft according to one of claims 1 to 4, characterized in that the wing cross-sections Laminar profiles are. 6. Aircraft according to claim 5, characterized in that the wing cross-sections are laminar profiles with S-runout, the positive moment coefficients own. 7. Aircraft according to claim 5, characterized in that the wing cross-sections are laminar profiles and the wing (1) at their rear end each have auxiliary wings (2) that protrude to the rear over the trailing edge of the wing and are released an air gap between the wing (1) and auxiliary wing (2) are attached to the wing. 8. Aircraft according to one of claims 1 to 7, characterized in that on each wing (1) an elevator (5) independent of the aileron (4) is provided, which is located near the fuselage and at least partially is located within the area of the widened wing chord. - 2a - 7302077 07/06/78 - 2a - 9. Aircraft according to one of claims 1 to 8, characterized in that there is a in its interior Device for ballast displacement contains, which is a movable by means of a servomotor carriage, which is in a Rail is guided, includes. 10. Aircraft according to claim 9, characterized in that the pilot's seat and / or in-flight drive, control and regulating devices are fixedly _{attached to the carriage of the device for ballast displacement un} g. 11. Aircraft according to one of claims 1 to 8, characterized in that it is in its interior
contains a device for ballast displacement, which contains at least two communicatingly connected liquid tanks and a liquid feed pump mounted in the connecting line. 7802077 07/06/78 12. Brushless aircraft trained as a glider according to one of claims 1 to 11, characterized in that there are two release devices or Hochstartaken (7), which are symmetrical on both sides of the longitudinal axis and each with a short Distance to the overall center of gravity (5) are arranged. 13. Aircraft according to claim 12, characterized that the two release devices or high start hooks (7) each at the point under one Hydrofoils are arranged near the fuselage, about the least Distance to the overall center of gravity (5) corresponds. 14. A brushless aircraft designed as a model aircraft according to any one of claims 1 to 13, characterized in that that the wing (1) has at its fuselage end a protruding shoulder (9) extending along the depth of the wing, which engages in a groove (10) in the fuselage (6) for a releasable fastening, the shape of which corresponds exactly to the shape of the attachment, that the wing (1) is adjusted by this fit with respect to the fuselage (6). 15. Airplane according to claim 14, characterized in that that the projection (9) can be fastened in the groove (10) by means of bolts (11). 16. Aircraft according to claim 14 or 15, characterized that the wing (1) is attached to the fuselage (6) by means of additional strips or struts (12) which protrude from the interior of the wing into the interior of the fuselage and by means of conventional fasteners, such as bolts, screws, snaps, split pins are attached inside the hull. 7802077 07/06/78