RU2764311C1 - Aircraft with vertical takeoff and landing and/or vertical takeoff and landing with shortened run - Google Patents

Abstract

FIELD: aviation.

SUBSTANCE: invention relates to the field of aviation, in particular, to designs of aircrafts with vertical or shortened takeoff and landing. The aircraft comprises a fuselage, wings located in the "tandem" arrangement, vertical tail, landing gear, a control system, a power unit, a propelling plant (PP). The PP consists of at least 8 lifting screws controlled by the speed of rotation, wherein each screw is rotated by a separate electric engine, and at least one cruise screw for creating a horizontal driving force, rotated by a cruise engine. The fuselage has a flattened power frame consisting of beams and spars. The lifting screws have the same diameter in the range of 1.5 to 2.8 m.

EFFECT: increase in the payload of at least 20% of the mass of the aircraft is provided with simultaneous increase in the range and duration of horizontal flight, for at least 5 hours.

12 cl, 8 dwg

Description

The present invention relates to aircraft (hereinafter referred to as aircraft), in particular to aircraft with the possibility of vertical takeoff and landing (VTOL) and / or with the possibility of vertical takeoff / forced landing with a short run, designed to transport people or goods.

Currently, one of the most common types of VTOL aircraft is a helicopter. Helicopters are used for vertical takeoff and landing. The helicopter is able to land and take off anywhere where there is a suitable site. However, to ensure takeoff and landing, these aircraft require a large diameter main rotor (HB) that creates lift. The angular velocity of rotation of the helicopter LP is significantly lower than the angular velocity of the power plant shaft, which leads to the use of heavy transmissions between the LP and the engine. Moreover, the large diameter of the HB requires a control system and careful selection of the landing site to prevent the blades from colliding with obstacles. Helicopters are also exposed to significant vibration loads. For these reasons, helicopters have a complex design. The reaction moment HB must be balanced either by the tail rotor or another main rotor, which further increases the structural complexity of the aircraft.

Another well-known type of VTOL aircraft are convertiplanes. This type of aircraft combines vertical takeoff and landing with the possibility of horizontal flight due to the rotation of the propellers from vertical to horizontal and the presence of wings that create lift in horizontal flight. However, complex and cumbersome mechanical systems for controlling the change in the position of the propellers lead to an increase in the complexity and weight of the aircraft, as well as greater labor intensity of maintenance. When landing, careful selection of a large obstacle-free area is required.

Other well-known VTOL aircraft are aircraft using either turbojet engine (TRD) thrust to support the aircraft during takeoff and landing (for example, Yak-141, Boeing X-32 JSF), or using turbojet engine thrust in combination with high-speed duct fan thrust, providing vertical takeoff and landing (for example, Lockheed-Martin X-35). The speed of the jet created by a turbojet engine or a lifting high-speed duct fan that provides lift is from 870 km / h for a lifting fan and up to 2200 km / h for a turbojet engine, while the temperature of the descending jet of a jet engine can reach 680 ° C. These types of aircraft can take off and land only from sites with a solid surface. The air flow control of these aircraft complicates their design and operation, and also requires a prepared landing site with a solid surface.

Thus, there is a need to create VTOL aircraft that are less complex in design, more reliable, with less requirements for a landing site, while still being suitable for transporting people or goods. To solve these problems, various VTOL aircraft have been developed, some of which are listed below.

Known VTOL aircraft (US 10414491 B2, IPC B64C 27/20, B64C 29/00, publ. 09/17/2019), having a cargo or passenger compartment attached from below to an integral wing, containing several engines that rotate a set of propellers, at the same time, under the integral wing on the pylons, a propulsion power plant is located, consisting of two engines.

The disadvantages of this arrangement is the need for large landing gear, creating additional aerodynamic drag and having a significant mass, while in the case of retractable landing gear, despite the reduction in aerodynamic drag, the mass of such landing gear will be even greater.

In addition, changing the position of the screws from horizontal to vertical requires a mechanical system, which is complex and can be significant in weight. The failure of such a mechanical system could render the aircraft uncontrollable.

Known multi-rotor aircraft (US 2020115045 A1, IPC B64C 29/00, B64D 27/24, publ. 04/16/2020) using only electric motors for movement, or with a hybrid power plant, using both electric motors and internal combustion engines (ICE) for movement ), made according to the tandem scheme with the upper location of the front and rear wings, which create most of the lift in level flight, and with the longitudinal placement of the lifting screws, which create most of the lift required by the aircraft during takeoff and landing, mounted on pylons attached to fixed wings. The aircraft has two longitudinal connecting beams, to which the passenger or cargo compartment is attached, in addition, the aircraft is controlled by automation.

The disadvantage of this solution is the difficulty of ensuring the strength of the developed spatial structure of the aircraft if you want to make it light, in addition, the entire mass of the wings, propellers and connecting elements rests on the passenger (cargo) compartment. This compartment must withstand all the loads that come to it and transfer them when landing on the chassis devices. As a result, the execution of both the landing gear and the passenger (cargo) compartment will be larger and heavier, and the large distance between the wings, propellers and landing gear will complicate the design due to the large number of attachment points. Also, the location of the propellers placed in the channels in the immediate vicinity of the leading edge of the aircraft wings leads to instability of the oncoming air flow, which leads to a decrease in the lift generated by the wings, as well as to a deterioration in controllability.

Known VTOL aircraft with a fixed wing (US 8636241 B2, IPC B64C 15/02, publ. 01/28/2014), containing a glider, including the fuselage and reverse sweep wings, trapezoidal front horizontal tail, rear horizontal tail sweep, two gas turbine engines that create thrust along the building horizontal of the apparatus and driving electrical generation devices, a plurality of electric fans that create lift, while the aircraft takes off, lands and hovering thanks to electric lift fans, and uses gas turbine engines to fly forward.

The disadvantage of this solution for a high-speed apparatus of this layout is the difficulty of placing high-power take-off propellers in the wing profile of small thickness.

An aircraft is known (US 8393564 B2, IPC B64C 27/22, published on March 12, 2013), which includes a fuselage, front and rear wings connected to the fuselage, several rotors located along the right and left sides of the fuselage, for lifting and controlling during takeoff, level flight, and landing, with two or more propellers to provide thrust for level flight.

This aircraft was chosen as a prototype, since it solves the identified problems of other VTOL aircraft as fully as possible, but it also has a drawback: in order to perceive and transfer the load to the chassis from the wings, takeoff and sustainer propellers and their power plants, for example, when landing, the fuselage and landing gear must have significant strength and, consequently, mass. This, in turn, leads to a decrease in the carrying capacity of the aircraft. With insufficient strength, the fuselage will collapse and the crew or payload will die.

Thus, at present, there is a need to create VTOL aircraft to ensure efficient and safe cargo and passenger transportation using unprepared or small runways, with the possibility of simplifying the aircraft design.

The aim of the invention is to create an efficient, safe and simple multi-rotor VTOL capable of using unprepared or small runways.

The technical result to which the invention is directed is the creation of a VTOL aircraft with an improved carrying capacity, namely with a payload of at least 20% of the total mass of the aircraft, while increasing energy efficiency, range and duration of horizontal flight, namely at least 5 hours, through the use of the shape and design of the fuselage.

The claimed technical results are achieved by creating an aircraft containing a fuselage, wings, vertical tail, landing gear, control system, power plant, propeller group, consisting of at least 8 takeoff propellers controlled by rotation speed, each of which is driven by a separate a take-off electric motor, and at least one main propeller for creating a horizontal driving force driven by a main engine, while the aircraft has a tandem arrangement of wings, and the fuselage has a flattened power frame, while the take-off propellers have the same diameter in the range 1 .5-2.8 m.

The power frame of the fuselage has a structure with transverse spars and longitudinal beams, reinforced profiles, and metal alloys and composite materials are used as materials for structural elements.

The fuselage contains through channels, within which the propeller group is fully integrated to create a vertical lifting force, while the through channels of the propeller group are made with the possibility of overlapping with airtight dampers, and the dampers are made in the form of pivotally mounted two-element flaps.

The propeller group for creating vertical lift is located in two parallel longitudinal rows.

Also, the wing consoles are fixed on the power frame of the fuselage from the side of the side fairings.

The vertical tail is attached to the power frame in the rear of the fuselage and protrudes upwards.

In this case, the sustainer engine is mounted on a motor mount mounted on a load-bearing frame in the rear of the fuselage.

The fuselage contains a passenger and/or cargo compartment, while the fuselage may additionally contain a crew cabin.

The essence of the invention and its advantages in relation to the prototype are disclosed in more detail in the context of the following description of the embodiment, given by way of illustration and with reference to the attached figures, in which:

Fig. 1 is an isometric front view of a VTOL aircraft;

Fig. 2 is an isometric rear view of the VTOL aircraft;

Fig. 3 - view of the VTOL device;

Fig. 4 - top view of VTOL aircraft;

Fig. 5 is a bottom view of the VTOL aircraft with open channel blocking devices during the vertical takeoff and landing phase;

Fig. 6 is a bottom view of the VTOL aircraft with closed channel blocking devices during the horizontal phase of flight;

Fig. 7 is a diagram of the direction of action of forces arising during level flight;

Fig. 8 is a diagram of the direction of the forces that occur during vertical takeoff and landing.

On FIG. 1-3 shows the longitudinal axis of symmetry O, as well as the vertical axis Y. The axis of symmetry O runs from the rear of the aircraft to the front of the aircraft.

On FIG. 1 and 2 shows an isometric view of a VTOL aircraft (1) containing a fuselage (3), as well as two wings containing front consoles (4), (6) and rear consoles (5), (7). The fuselage (3) contains a propeller group (VMG), which consists of eight electric motors (26) with take-off propellers (8) located in the respective through channels (9), as well as a motor mount (19) (see Fig. 3), on which has a sustainer engine (10) and a sustainer propeller (11).

The fuselage (3) contains a passenger and/or cargo compartment (2), which is located and extended along the axis of symmetry O, while smoothly connected with the upper (12) fuselage skin (3).

In another embodiment, the fuselage (3), in addition to the passenger and/or cargo compartment (2), additionally contains a cabin with a crew.

Compartment (2) has a streamlined shape, that is, it has a rounded cross-section and smooth bends, which give the least drag when air flows around the aircraft.

On FIG. 3 shows how passengers are accommodated in compartment (2).

The power frame of the fuselage (3) has a beam-spar design with transverse spars (27) and longitudinal beams, reinforced profiles (28) (see Fig. 3). The surface of the fuselage (3) consists of the upper (12) and lower (13) skin sections, side fairings (14), (15), as well as front (16) and trailing (17) edge fairings. The edge fairings (16), (17) have smaller transverse dimensions than the longitudinal dimensions of the fairings (14), (15).

On FIG. 4 it can be seen that the edge fairings (16), (17) are made rounded, however, they can be made straight or swept. Also, the edge fairings (16), (17) are profiled to reduce the resistance of the oncoming air flow during the horizontal flight of the aircraft.

The fuselage (3) has a flattened power frame with skin. Simplified, the shape of the fuselage can be represented in the form of a parallelepiped. Another version of the fuselage (3) can be a load-bearing frame with skin, while the upper section (12) of the skin is convex in the direction of the Y axis, and the lower section (13) forms a horizontal plane. The fuselage (3) may have other versions of the streamlined shape. That is, the fuselage (3), together with the power frame and skin, has a streamlined shape that reduces drag and is able to create additional lift, reducing the required area of the wings, thereby reducing drag and increasing the range and duration of horizontal flight, namely at least 5- ty hours, compared to other multi-rotor VTOL aircraft. Also, due to the streamlined shape of the fuselage (3), the energy efficiency of the VTOL aircraft increases, since this allows you to increase the range and duration of the horizontal flight of the VTOL aircraft without the need to increase the amount of aviation fuel. Sections (12), (13) of the skin are smoothly connected with the side fairings (14), (15), as well as with the fairings of the front (16) and rear (17) edges of the fuselage (3).

The presence of a strong fuselage (3) provides a rigid relationship between the wing consoles (4)-(7), VMG, main engine (10), thereby perceiving and distributing the loads that the aircraft is subjected to in flight, due to the shape of the fuselage (3) and power frame. The claimed design of the fuselage (3) makes it possible to achieve the shortest distance between the wing consoles (4)-(7), VMG, main engine (10) and landing gear (24), thereby reducing the dimensions of the VTOL aircraft, and also allowing to get rid of attachment points and simplify construction. Due to this, the weight of the VTOL aircraft decreased, which in turn made it possible to increase the carrying capacity. Empirically, it was found that the value of the VTOL payload with this configuration of the fuselage (3) can reach 20% of the total mass of the VTOL aircraft.

Also, the fuselage structure (3) can absorb the energy of a collision with the ground during an emergency landing due to its deformation, reducing the injury to the crew.

The fuselage (3) has through channels (9) for eight takeoff propellers (8) of the VMG. The channels (9) are built into the fuselage (3) and arranged vertically. The channels (9) are located symmetrically with respect to the longitudinal vertical plane of symmetry of the aircraft, thus their two-row arrangement minimizes the overall dimensions of the aircraft and sets the shape of the fuselage (3). The channels have the same dimensions, namely not less than 1.4 m and not more than 2.9 m, and are round. Each channel has a toroidal top edge. The channels serve to protect the take-off propeller blades (8) from collision with various objects, which allows this VTOL aircraft to use areas less prepared for take-off and landing than conventional runways, and also reduce aerodynamic drag.

The placement of the take-off screws (8) VMG in the fuselage (3) allows you to use a lighter design of the wing consoles (4)-(7).

In FIG. 5 and 6 it can be seen that the through channels (9) are equipped with airtight hinged shutters (18), which can be sliding and simultaneously folding in pairs in the transverse direction two-element flaps. The dampers (18) prevent air from flowing through the VMG channels during level flight, allowing to reduce drag and increase the carrying capacity of the fuselage (3).

Side fairings (14), (15) of the fuselage (3) hide the attachment points of the consoles (4)-(7) from the oncoming air flow.

The wing consoles (4)-(7) are fixed on the fuselage load-bearing frame (3) from the side of the side fairings (14), (15). The removal of the wing consoles (4)-(7) of the aircraft on the side fairings (14), (15) of the fuselage (3) reduces the influence of the operating VMG on them, which makes it possible to reduce their geometric dimensions, thereby reducing their weight.

This layout of the wings (tandem) makes it possible to abandon the presence of a horizontal tail, which in turn leads to a decrease in the weight and dimensions of the aircraft, respectively, an increase in carrying capacity, and also increases its energy efficiency in level flight.

In FIG. 7 illustrates the forces that occur in level flight, where G is the force of gravity directed downwards, and F1 are the lift forces created by the wings, opposing the force of gravity G.

For the production of aircraft structural elements, metal alloys and composite materials can be used.

On the power frame in the rear part of the fuselage (3), symmetrically about the axis O, closer to the fairing of the trailing edge (17), the motor frame (19) is attached, shown in Fig. 3. A main engine (10) with a main propeller (11) is rigidly fixed on the motor mount (19). The motor mount (19) perceives the forces and moments created by the propeller (11) during the horizontal flight of the aircraft.

Wing consoles (4)-(7) are made with elevons (20). Elevons (20) allow you to control the roll and pitch of the aircraft.

In the preferred design of the VMG aircraft, it consists of eight take-off propellers (8) with blades, each of which is mounted on the hub (25) of a separate power plant in the form of a take-off electric motor (26), while the take-off electric motors (26) are supported by pylons (21), mounted on reinforced nodes of the walls of the through channels (9) of the fuselage (3).

Take-off propellers (8) have a fixed pitch with vertically located rotation axes, forming a row consisting of 4 take-off propellers (8), while the rows are arranged symmetrically with respect to the longitudinal vertical plane of symmetry. The take-off propellers (8) of the VMG are fully integrated within the respective through channels (9). The take-off propellers (8) have the same diameters in the range of 1.5-2.8 m. It has been experimentally established that the stated take-off propeller diameter range (8) allows for vertical take-off with a payload of at least 20% of the total aircraft mass, with the takeoff speed reaches 5 m/s.

The relatively small dimensions of the VMG make it possible to have a smaller moment of inertia of the rotating screw, and, consequently, a shorter response time to the control signal of the control system.

The use of a large number of take-off propellers (8) makes it possible to use the possibility of an emergency landing in case of failure of several of them (up to 2 propellers).

In FIG. Figure 8 illustrates the forces that occur during vertical takeoff and landing of an aircraft, where G is the force of gravity directed downward, and F2 are the lift forces created by the VMG, counteracting the force of gravity G. The takeoff propellers (8) are located with an offset relative to the compartment (2), so that their air jets do not collide with the surface of the compartment. Thus, all created moments and forces arising during the operation of the VMG are perceived by the elements of the fuselage (3). Changes in lift are achieved by changing the speed of rotation of the take-off propellers (8).

In the claimed invention, the VMG is located symmetrically with respect to the center of mass of the aircraft. The balancing of the aircraft is achieved by a complete balancing of the masses of all onboard systems. The crew (in the corresponding variant of the fuselage design) is located in the compartment (2) in the region of the center of gravity.

The number of takeoff propellers (8) of the VMG rotating in one direction is equal to the number of propellers rotating in the opposite direction. Therefore, the reactive moments resulting from the rotations of these screws cancel each other out.

The hub (25) of each takeoff propeller (8) is connected directly to the takeoff motor shaft (26), respectively, the angular velocity of the shaft and the corresponding takeoff motors (26) is the same.

The aircraft contains at least one electric storage battery located in the fuselage (3) (not shown).

Any existing or prospective engines can be used as a main engine (10) of an aircraft, for example: internal combustion engines, electric motors, jet, turbojet, turboshaft, etc.

On the power frame in the rear of the fuselage (3) is mounted vertical plumage (22), (23), which protrudes upwards near the trailing edge fairing (17). Vertical plumage (22), (23) with rudders provide directional control and course stability of the aircraft.

Also, the fuselage (3) contains, in the preferred design, six landing gear legs (24) protruding downward.

The electrical remote control system of the aircraft contains actuators (IM) (not shown) for controlling the elevons (20) and rudders.

For the operation of the onboard control system, the aircraft has a set of sensors.

LA VTOL contains a system of manual and automatic control (not shown). These systems are well known and will be described below.

The aircraft is controlled through the interface of the on-board computer (not shown) connected to the takeoff motors (26) of the takeoff propellers (8), the main engine (10), the elevon IMs (20), rudders and other subsystems of the aircraft.

The on-board computer of the aircraft regulates the traction forces of each of the take-off propellers (8) by changing the angular speeds of rotation. The on-board computer controls the individual traction forces in such a way that the aircraft can lean forward, backward (in pitch) or sideways (in roll). To increase or decrease the flight altitude, it is necessary to jointly increase or decrease the thrust of all take-off propellers (8) through purposeful changes in angular velocities. The total reactive moment of the takeoff propellers (8) relative to the vertical axis of the aircraft can act in a clockwise direction, or in a counterclockwise direction. The control of the aircraft relative to the vertical axis (along the course) is carried out by changing the magnitude and direction of the total reactive moment of the VMG.

The transfer of the aircraft from the mode of vertical takeoff to horizontal flight upon reaching a predetermined altitude is carried out by the appearance of the propulsion force of the propulsion engine (10). Gradual reduction of takeoff propeller thrust (8) begins after gaining sufficient speed to create the necessary lift force by wing consoles (4)-(7). After reaching sufficient bearing capacity of the wing consoles (4)-(7), the take-off propellers (8) stop and their channels (9) are blocked by airtight dampers (18). The aircraft enters the vertical landing mode after the airtight dampers (18) are opened and the take-off propellers (8) begin to rotate with an increase in the thrust they create to a level sufficient to balance the weight of the aircraft and a further decrease in the horizontal flight speed.

Thus, the on-board computer provides vertical takeoff or landing, hovering, as well as transitional modes, when the aircraft needs to switch from vertical takeoff mode to horizontal flight mode and vice versa for vertical landing.

A typical aircraft flight profile assumes vertical takeoff and landing. In the event of a forced or emergency landing, the device can land on an aircraft with sliding on a skid landing gear.

Claims (12)

1. An aircraft containing a fuselage, wings, vertical tail, landing gear, control system, power plant, propeller group, consisting of at least 8 take-off propellers controlled by rotation speed, each of which is driven by a separate take-off electric motor, and at least one main propeller for creating a horizontal driving force driven by a main engine, characterized in that the aircraft has a tandem arrangement of wings, and the fuselage has a flattened power frame, while the take-off propellers have the same diameter in the range 1, 5-2.8 m. 2. The aircraft according to claim. 1, characterized in that the power frame of the fuselage has a design with transverse spars and longitudinal beams, reinforced profiles. 3. The aircraft according to claim 1, characterized in that metal alloys and composite materials are used as materials for structural elements. 4. The aircraft according to claim 1, characterized in that the fuselage contains through channels, within which the propeller group is fully integrated to create vertical lift. 5. The aircraft according to claim 1 or 4, characterized in that the propeller group for creating vertical lift is located in two parallel longitudinal rows. 6. The aircraft according to claim. 4, characterized in that the through channels of the propeller group are made with the possibility of overlapping airtight dampers. 7. The aircraft according to claim 6, characterized in that the dampers are made in the form of hinged two-element flaps. 8. The aircraft according to claim 1, characterized in that the wing consoles are fixed on the fuselage power frame from the side of the side fairings. 9. The aircraft according to claim. 1, characterized in that the vertical tail is fixed on the power frame in the rear of the fuselage and protrudes upward. 10. The aircraft according to claim 1, characterized in that the sustainer engine is mounted on a motor mount mounted on a power frame in the rear of the fuselage. 11. The aircraft according to claim 1, characterized in that the fuselage contains a passenger and/or cargo compartment. 12. The aircraft according to claim 11, characterized in that the fuselage additionally contains a cockpit.

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