RU2728017C2 - Short take-off and landing aircraft - Google Patents

Abstract

FIELD: aircraft; machine building.SUBSTANCE: invention relates to the field of aircraft engineering, in particular, to development of cargo, passenger and multi-purpose aircraft of short take-off and landing, providing cargo-passenger transportation, rescue operations, and so forth in areas with underdeveloped aerodrome network and requiring shoulder transportation of more than 600…1000 km. In aircraft of short take-off and landing, comprising wing, fuselage, power plant and lines of fan-type propellers on deflectable flaps, for joint of wing with fuselage and arrangement of power plant additionally contains connecting fairing, made in form of small elongated profiled root wing with inclination angles of 10…60° of its lower and upper surfaces coupled with fuselage relative to horizontal plane, with relative profile thickness of 10…20 %. In the fuselage tail part there are two cantilevers forming V-shaped fins, and fuselage elevator, ahead of which there is an additional line of fan propulsors.EFFECT: proposed aircraft ensures high bearing properties of wing in interaction with power plant at take-off and landing modes, reduction of front drag on cruise modes of flight and provision of high level of weight perfection of aircraft.3 cl, 2 dwg

Description

The invention relates to the field of aircraft construction, in particular, to the development of cargo, passenger and multipurpose aircraft for short takeoff and landing, providing cargo and passenger transportation, rescue operations, etc. in areas with an underdeveloped airfield network and requiring a transportation shoulder of more than 1000 km (for example, in the Arctic and East Siberian regions).

Known aircraft An-28, developed by the OKB im. Antonov (see www.aviawiki.com \ antonov \ an-28) and its analogues (DO-228NG, DHC-6-400, L-410UVP-E20, C-212-400, etc.). In the standard version, the aircraft have a take-off run of 300 ... 400 m and a run length of 200 ... 300 m. Since the design case is an engine failure, the runway length required for them is 550 ... 900 m. The aircraft cruise at an altitude of up to 3 km at a speed of 300 … 400 km / h and have a maximum flight range (ferry) of 1300… 1800 km. The aircraft are made according to the normal aerodynamic configuration with a wing of high aspect ratio mechanized along the trailing edge. The power plant with turboprop engines (TVD) and relatively large-diameter propellers is located on a wing blown from the propellers. The aircraft contain a fuselage, which houses the cockpit, equipment, cargo and passenger cabin. The horizontal and vertical empennage is installed on the aft fuselage.

Also known are hybrid short take-off and landing aircraft containing engines of a hybrid power plant on the wings (RF patent No. 2577931 IPC В64С 29/00; 27/28 dated 20.03.2016)

The disadvantages of these aircraft are the large area of the washed surface, the large relative weight of the airframe and, as a consequence, the relatively low cruising speed (up to 400 km / h) and range (up to 1500 km). In addition, the take-off and landing distance is over 550 m.

There is a known project of the Onera Amhere aircraft (France, www.onera.fr \ Fiche_AMPERE_VA) with a distributed electric power plant, which uses 32 electric tunnel fans installed above the leading edge of the wing. The aircraft is designed for a flight range of 400 ... 500 km at a speed of 200 ... 250 km / h.

The disadvantages of this aircraft are low cruising speed and flight range.

Closest to the proposed invention is the Lilium vertical takeoff and landing aircraft project developed in Germany (see felix.schoefer@lilium.com). It is assumed that the aircraft will be equipped with an electric power plant, carry out vertical take-off and landing on a hard surface without additional special training and will provide flight at an altitude of up to 3 km at a speed of up to 300 km / h for a distance of up to 500 km. The aircraft has a tailless design and contains a wing, a fuselage, a power plant and a series of fan propellers on tiltable flaps. To balance the aircraft in the take-off and landing mode, electric fan lifting motors are used that are retracted into the nose of the fuselage in flight. The aircraft has an almost straight wing of moderate aspect ratio.

The disadvantages of this aircraft are low cruising speed and flight range.

As a result, these shortcomings do not allow effective use of these aircraft in areas with an underdeveloped airfield network with transportation distances of more than 1000 km (the round trip flight time is more than 7 hours).

The objective of this invention is the development of a highly efficient short take-off and landing aircraft with a distributed power plant, providing an increase in the cruise flight speed to 600 ... 750 km / h while reducing the required runway length to 300 ... 350 m and ensuring all-weather performance while maintaining high levels of safety and low costs for operation.

The technical result consists in achieving high bearing properties of the wing in interaction with the power plant at takeoff and landing modes, reducing drag at cruising flight modes and ensuring a high level of weight perfection of the aircraft.

The technical result is achieved by the fact that a short take-off and landing aircraft containing a wing, a fuselage, a power plant and a line of fan thrusters on tiltable flaps, for articulating the wing with the fuselage and placing the power plant, additionally contains a connecting fairing made in the form of a profiled root wing of low aspect ratio with tilt angles of 10 ... 60 ° of its lower and upper surfaces mating with the fuselage relative to the horizontal plane, with a relative profile thickness of 10 ... 20%, and in the aft fuselage there are two V-tail consoles and a fuselage elevator, in front of which there is an additional ruler fan propellers.

The technical result is also achieved by the fact that the flaps are made of two links with the ability to rotate the first link at angles of 0 ° -40 °, and the second link by ± 20 ... 30 ° relative to the plane of the first.

The technical result is also achieved by the fact that the line of fan propellers has a mechanical or electrical drive from a power plant.

The invention is illustrated in drawings, where FIG. 1 (a, b, c) shows a diagram of an aircraft, and Fig. 2 section A-A along the wing console.

The aircraft is made according to the normal aerodynamic configuration (see Fig. 1a, b, c), and contains a fuselage 1; wing consoles 2; connecting fairing 3 smooth articulation of the wing spars with the fuselage frames 13; power plant, including air intakes 5, turboshaft engines 6 and electric generators 7; fuselage elevator 10, tail line of fan thrusters 8, V-shaped empennage consoles 14, high-bearing surfaces 12. In Fig. 2, in section of the wing A-A, the lines of fan thrusters 15 on the deflected flaps 4 and the second link of flaps 11 are also shown.

The connecting fairing 3 of the articulation of the wing spars with the fuselage frames 13 is made in the form of a profiled root wing of low aspect ratio with inclination angles of 10 ... 60 ° of its lower and upper surfaces mating with the fuselage relative to the horizontal plane, with a relative profile thickness of 10 ... 20% and provides weight reduction power structure, volumes sufficient to accommodate the power plant, fuel and landing gear with a minimum increase in the area of the aircraft washed surface.

The flat tail section of the fuselage with the elevator 10, smoothly coupled with the rear inflow and consoles of the V-shaped empennage 14, provides pitch control, smooth continuous flow and balancing of the aircraft in cruise flight modes.

The deviation of the first flap link 4 (Fig. 2) with a line of fan propellers 15 at angles of 0 ... 40 ° is due to the need to achieve an acceptable level of aerodynamic quality in take-off and go-around modes during landing and, thereby, reduce the required thrust-to-weight ratio with a short takeoff run and, consequently, a decrease in the required power and weight of the power plant. The use of a jet-blown rotary second flap link 11 with deflection angles of ± 20 ... 30 ° relative to the plane of the first link provides a deviation of the thrust vector to control the values of the longitudinal and vertical forces in takeoff and landing modes with relatively small hinge moments.

The location in front of the fuselage elevator 10 (see Fig. 1a) of the line of fan propellers 8 increases the pitch control efficiency and provides an increase in the efficiency of the fans in cruising flight due to the suction of the boundary layer from the large washed fuselage area into the propellers. The use of a jet-blown fuselage elevator 10 with deflection angles of ± 20 ... 30 ° provides a deflection of the thrust vector to control the values of the longitudinal force and pitching moment in takeoff and landing modes with relatively low hinge moments.

Installed in the nose of the aircraft, high-bearing surfaces 12, which are extended during takeoff and landing and retracted during cruise flight, create a pitching moment comparable in magnitude with the diving moment from the flaps extended and, thereby, reduce the loss of lift for balancing by the tail. High-bearing surfaces can be made in the form of a multi-link wing of large curvature or in the form of hyper-bearing surfaces (RF patent No. 96114015, IPC В64С 9/00 20.04.1998).

Power supply of fan propellers 15 and 8 driven by electric motors is provided by a power plant that includes, along with electric accumulators, at least two driving electric generators 7, turboshaft engines 6 with air intakes 5 and exhaust nozzles. At the same time, in order to reduce the weight of electric accumulators, their capacity is limited by a supply of energy sufficient to power traction motors for 1 ... 2 minutes. if one of the turboshaft engines fails.

To increase the engine power in cruise flight at high speed, in front of the air inlet into the turboshaft engine, an additional fan 9 is installed, driven by the TVaD turbine.

To increase the permissible angle of attack under the influence of the calculated vertical gust of wind at takeoff and landing flight modes and the critical value of the Mach number in cruise flight, wing consoles 2 have a sweep angle along the leading edge of 30 ... 45 °. To maintain high efficiency of mechanization along the trailing edge, the sweep angle of the trailing edge should not exceed ± 15 °.

In some cases, to reduce the weight of the power plant, the line of fan motors can be mechanically driven by turboshaft engines.

The rest of the elements, units and systems are made on the basis of well-known principles and design methods.

Thus, the object and the technical result of the invention are achieved due to the proposed connecting fairing integrated with the fuselage and wing consoles, a line of fan propellers, a power plant with turboshaft engines, a fuselage elevator with a line of fan propellers, a swept wing of moderate aspect ratio, a pressurization fan of the TVAD. The simultaneous use of these features and their rational mutual arrangement ensures the achievement of high bearing properties of the wing in takeoff and landing modes, a decrease in frontal resistance in cruise flight modes and a high level of weight and aerodynamic perfection of the aircraft.

Computational and design studies show that, in comparison with the prototype, the aircraft, made in accordance with the proposed technical solutions, provides a take-off and run length of 200 ... 250 m, a cruising speed of 600 ... 750 km / h and a practical range of 2000 ... 2500 km at approximately the same costs for operation.

Claims (3)

1. A short take-off and landing aircraft containing a wing, a fuselage, a power plant and a line of fan thrusters on tiltable flaps, characterized in that for articulation of the wing with the fuselage and placement of the power plant, it additionally contains a connecting fairing made in the form of a profiled root wing of low aspect ratio with tilt angles of 10 ... 60 ° of its lower and upper surfaces mating with the fuselage relative to the horizontal plane, with a relative profile thickness of 10 ... 20%, and in the aft fuselage there are two consoles forming a V-shaped tail, and a fuselage elevator in front of which is located additional line of fan propellers. 2. A short take-off and landing aircraft according to claim 1, characterized in that the flaps are made of two links with the ability to rotate the first link at angles of 0-40 °, and the second link by ± 20 ... 30 ° relative to the plane of the first. 3. A short take-off and landing aircraft according to claim 1, characterized in that the line of fan propellers has a mechanical or electrical drive from a power plant.

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