A method for designing an aircraft takeoff assist device

Abstract

The application belongs to the technical field of aircraft power device design, and particularly relates to a design method of an aircraft take-off assisting device. The take-off assisting device is installed at the lower part of an aircraft. The design method comprises: designing a power module, a connecting module, a control module and a supporting walking module for the take-off assisting device, wherein the power module is used for providing power for the take-off assisting device; the connecting module is used for connecting and separating the take-off assisting device and the aircraft; the control module is used for controlling the take-off assisting device; and the supporting walking module is used for supporting the take-off assisting device to walk. The application increases the acceleration of the aircraft during take-off acceleration taxiing, shortens the take-off runway, and improves the take-off performance of the aircraft. In addition, the process of enhancing the take-off performance does not increase the empty weight and aerodynamic resistance of the aircraft. Finally, the design constraint of the airborne engine related to the take-off performance is solved, and the airborne engine can be optimized and designed according to the requirements of high-speed flight.

Description

A design method for an aircraft takeoff assist device Technical Field

[0001] This application belongs to the field of aircraft power plant design technology, and specifically relates to a design method for an aircraft takeoff assist device. Background Technology

[0002] Fixed-wing aircraft require runway support for takeoff. At the runway's takeoff line, the aircraft increases engine throttle and releases the brakes, increasing its takeoff speed. Once the aircraft reaches the designated speed, it sequentially lifts off the nose wheel and then the main wheels.

[0003] The takeoff length of an aircraft must meet the runway length requirements; that is, the equilibrium takeoff length cannot exceed the runway length. If the equilibrium takeoff length exceeds the runway length, the aircraft's weight needs to be reduced to ensure the new weight condition allows the equilibrium takeoff length to meet the runway length requirements. Reducing the takeoff weight leads to a decrease in payload or fuel, thus reducing the aircraft's mission capabilities. Conversely, increasing the takeoff weight leads to an increase in payload or fuel, thus improving the aircraft's mission capabilities. In conclusion, improving an aircraft's takeoff performance will improve its mission capabilities.

[0004] Improving takeoff performance during aircraft design is currently very difficult. This is mainly due to the challenges of enhancing aerodynamics, strict weight control, and the potential for imbalance between the aircraft and its engine.

[0005] Improving aerodynamic performance is challenging. The main aerodynamic parameter affecting aircraft takeoff performance is lift characteristics, and there are many constraints on improving lift characteristics in civil aircraft design. Firstly, noise requirements limit the design of lift-enhancing devices; secondly, newly developed blended wing-body passenger aircraft have weak longitudinal control capabilities, making it difficult to use efficient lift-enhancing devices. Therefore, progress in improving lift characteristics in civil aircraft is not significant.

[0006] Weight control is stringent. The primary parameter affecting an aircraft's takeoff acceleration is engine thrust, and there are currently many constraints on increasing engine thrust in civil aircraft. Under the same thrust-to-weight ratio, higher engine thrust results in higher engine weight, which in turn increases the aircraft's empty weight and reduces its fuel economy. Therefore, it is difficult for aircraft to surpass competitors by selecting engines with significantly higher thrust.

[0007] Engine-flight mismatch. An aircraft's cruise performance is positively correlated with its aerodynamic efficiency. Higher aerodynamic efficiency results in lower drag under the same cruise flight conditions, leading to better fuel economy. Therefore, improving aerodynamic efficiency during cruise flight is a design goal for engineers. However, engineers face a mismatch between aerodynamic and propulsion design parameters when trying to improve cruise aerodynamic efficiency. Specifically, increasing cruise aerodynamic efficiency requires relatively less cruise thrust to meet cruise flight requirements; if classic propulsion parameters are used, cruise thrust will be excessive, and the advantages of reduced cruise thrust will not be fully realized. Conversely, using smaller propulsion parameters will correspondingly reduce takeoff thrust, failing to meet takeoff range requirements.

[0008] To improve the overall performance of an aircraft, it is necessary to enhance its takeoff and cruise performance. Cruise performance can be improved by increasing aerodynamic efficiency, while takeoff performance can be improved by increasing takeoff thrust. Therefore, under various design constraints, one of the key requirements is to increase takeoff thrust without significantly increasing the aircraft's empty weight; another is to increase takeoff thrust without increasing cruise drag; and yet another is to increase takeoff thrust in line with the cruise thrust design point.

[0009] Therefore, it is desirable to have a technical solution to overcome or at least mitigate one of the aforementioned defects of the prior art. Summary of the Invention

[0010] The purpose of this application is to provide a design method for an aircraft takeoff assist device to solve at least one problem existing in the prior art.

[0011] The technical solution of this application is:

[0012] A design method for an aircraft takeoff assist device, wherein the takeoff assist device is installed on the lower part of the aircraft, and the design method includes:

[0013] The takeoff assist device is designed with a power module, a connection module, a control module, and a walking support module, wherein,

[0014] The power module is used to provide power to the takeoff assist device;

[0015] The connection module is used to connect and disconnect the takeoff assist device from the aircraft.

[0016] The control module is used to control the takeoff assist device;

[0017] The walking support module is used to support the walking of the takeoff assist device.

[0018] In at least one embodiment of this application, the aircraft includes a central body, wings, onboard engines, and landing gear, wherein,

[0019] The wings include a left wing and a right wing, which are symmetrically arranged on the left and right sides of the central body of the aircraft, respectively.

[0020] The airborne engines include a left airborne engine and a right airborne engine, which are symmetrically arranged on the upper part of the central body of the aircraft.

[0021] The landing gear includes a nose landing gear, a left rear landing gear, and a right rear landing gear, which are respectively arranged in the lower part of the central body of the aircraft.

[0022] In at least one embodiment of this application, the power module includes an aircraft engine, an intake unit, and an exhaust unit.

[0023] In at least one embodiment of this application, the air intake unit ensures that the air entering the aircraft engine is free of impurities.

[0024] In at least one embodiment of this application, the exhaust unit ensures that the exhaust flow from the aircraft engine does not damage the aircraft.

[0025] In at least one embodiment of this application, the control module includes:

[0026] The driving direction control unit is used to control the driving direction of the takeoff assist device;

[0027] Throttle position control unit, used to control the throttle position of the takeoff assist device;

[0028] The brake control unit is used to control the brakes of the takeoff assist device.

[0029] In at least one embodiment of this application,

[0030] Once the takeoff assist device establishes a connection with the aircraft, the aircraft gains access to operate the takeoff assist device.

[0031] In at least one embodiment of this application,

[0032] When the takeoff assist device is disconnected from the aircraft, the takeoff assist device regains its own operating authority.

[0033] In at least one embodiment of this application, the walking support module includes:

[0034] The support unit is connected to the takeoff assist device;

[0035] Tires are mounted at the bottom of the support unit;

[0036] A braking unit is mounted on the tire.

[0037] In at least one embodiment of this application, the takeoff assist device is used as follows:

[0038] The aircraft increases all throttle and releases the brakes at the takeoff line, and the aircraft accelerates its taxiing.

[0039] If an engine fails before the critical engine failure speed, the pilot reduces all throttle, opens the spoilers, applies the brakes, and aborts takeoff.

[0040] If no engine fails before the critical engine failure speed, the pilot reduces the throttle of the takeoff booster before lifting the nose wheel speed, and disconnects the aircraft from the takeoff booster after the acceleration of the takeoff booster is less than the acceleration of the aircraft.

[0041] The takeoff assist device brakes and decelerates, increasing the distance between the aircraft and the takeoff force.

[0042] The aircraft completed the takeoff operation according to the standard takeoff procedure.

[0043] The invention has at least the following beneficial technical effects:

[0044] The aircraft takeoff assist device design method of this application provides a power layout design that balances aircraft takeoff performance and cruise performance, achieving the goal of improving takeoff performance while maintaining the improvement in cruise performance. This application increases the aircraft's acceleration during takeoff acceleration roll, shortens the takeoff field length, and improves the aircraft's takeoff performance; secondly, the process of enhancing takeoff performance does not increase the aircraft's empty weight or aerodynamic drag; finally, it removes the design constraints of the airborne engine related to takeoff performance, allowing the airborne engine to be fully optimized according to the requirements of high-speed flight. Attached Figure Description

[0045] Figure 1 is an isometric view of an aircraft equipped with a takeoff assist device according to one embodiment of this application;

[0046] Figure 2 is a front view of an aircraft equipped with a takeoff assist device according to one embodiment of this application;

[0047] Figure 3 is a side view of an aircraft equipped with a takeoff assist device according to one embodiment of this application;

[0048] Figure 4 is a top view of an aircraft equipped with a takeoff assist device according to one embodiment of this application.

[0049] Figure 5 is a bottom view of an aircraft equipped with a takeoff assist device according to one embodiment of this application.

[0050] Figure 6 is a side view of a takeoff assist device according to one embodiment of this application;

[0051] Figure 7 is a front view of a takeoff assist device according to one embodiment of this application.

[0052] in:

[0053] 1-Aircraft central body; 2-Wing; 3-Airborne engine; 4-Aircraft; 5-Landing gear; 6-Takeoff assist device; 7-Takeoff assist device housing; 8-Power module; 9-Control module; 10-Tire; 11-Brake module; 12-Support unit. Detailed Implementation

[0054] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The described embodiments are some, but not all, embodiments of this application. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application. The embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0055] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this application.

[0056] The present application will now be described in further detail with reference to Figures 1 to 7.

[0057] This application provides a design method for an aircraft takeoff assist device 6, which is installed on the lower part of the aircraft 4. The design method includes:

[0058] The takeoff assist device 6 is designed with a power module 8, a connection module 9, and a walking support module.

[0059] Power module 8 is used to provide power to takeoff assist device 6;

[0060] The connection module is used to connect and disconnect the takeoff assist device 6 from the aircraft 4;

[0061] The control module 9 is used to control the takeoff assist device 6;

[0062] The walking module is used to support the walking of the takeoff assist device 6.

[0063] The aircraft takeoff assist device design method of this application includes a takeoff assist device 6, which is a self-propelled device equipped with an aircraft engine 8, also referred to as a takeoff vehicle. The power module 8 consists of the aircraft engine and its associated intake and exhaust units. The connection module is responsible for connecting and disconnecting the takeoff vehicle from the aircraft 4. The control module 9 is responsible for operating the takeoff vehicle, including driving direction, throttle position, and brake control. The support module includes a support unit 12, tires 10, and a brake unit 11. Before takeoff, the takeoff assist device 6 connects to the aircraft 4, and the aircraft engine on the device assists the aircraft 4 in accelerating. Before the aircraft 4 lifts its nose wheels, the throttle of the device is reduced, and the device is disconnected from the aircraft 4. Afterward, the aircraft 4 takes off, and the takeoff vehicle uses the brakes to decelerate.

[0064] Specifically, as shown in Figures 1-5, the aircraft 4 includes a central body 1, wings 2, airborne engines 3, and landing gear 5. The wings 2 include a left wing and a right wing, symmetrically arranged on the left and right sides of the central body 1, respectively. The airborne engines 3 include a left airborne engine and a right airborne engine, symmetrically arranged on the upper part of the central body 1, respectively. The landing gear 5 includes a nose landing gear, a left rear landing gear, and a right rear landing gear, respectively arranged on the lower part of the central body 1. In this embodiment, the aircraft 4 adopts a blended wing-body layout, and the takeoff assist device 6 is also applicable to aircraft with a conventional layout.

[0065] As shown in Figures 6-7, in a preferred embodiment of this application, the power module 8 includes an aircraft engine, an air intake unit, and an exhaust unit. The air intake unit ensures that the air entering the aircraft engine is free of impurities, and the exhaust unit ensures that the exhaust jet from the aircraft engine will not damage the aircraft 4. The design of the power unit 8 for the takeoff vehicle ensures that the air entering the aircraft engine is free of impurities, and the exhaust unit ensures that the exhaust jet from the aircraft engine will not damage the aircraft. The aircraft engine requires a high thrust-to-weight ratio and small geometric dimensions. There are no strict requirements on the fuel consumption rate of the aircraft engine; the requirement is that the thrust of the aircraft engine in takeoff mode matches the capability requirements of the aircraft's takeoff range length.

[0066] In a preferred embodiment of this application, the control module 9 includes: a driving direction control unit for controlling the driving direction of the takeoff assist device 6; a throttle position control unit for controlling the throttle position of the takeoff assist device 6; and a brake control unit for controlling the braking of the takeoff assist device 6. The takeoff vehicle control authority is allocated as follows: when the takeoff assist device 6 establishes a connection with the aircraft 4, the aircraft 4 acquires the operating authority of the takeoff assist device 6, including steering, throttle, and braking; when the takeoff assist device 6 disconnects from the aircraft 4, the takeoff assist device 6 regains its own operating authority and can perform operation and shutdown operations according to its own needs.

[0067] In a preferred embodiment of this application, the walking support module includes: a support unit 12 connected to the takeoff assist device 6; a tire 10 mounted on the bottom of the support unit 12; and a braking unit 11 mounted on the tire 10.

[0068] It is understood that in this embodiment, one takeoff booster device 6 is installed on the aircraft 4, and designs with two or three takeoff booster devices 6 are also applicable. One aircraft engine, or two or three aircraft engines, can be installed on the takeoff booster device 6.

[0069] The aircraft takeoff assist device design method of this application, the takeoff assist device 6 is used as follows:

[0070] Aircraft 4 increases all throttle (including the onboard engines of aircraft 4 and the aircraft engines on takeoff booster 6) and releases the brakes at the takeoff line, and aircraft 4 accelerates and rolls.

[0071] If an engine fails before the critical engine failure speed, the pilot reduces all throttle, opens the spoilers, applies the brakes, and aborts takeoff.

[0072] If no engine failure occurs in aircraft 4 before the critical engine failure speed, the pilot reduces the throttle of takeoff booster 6 before lifting the nose wheel speed, and disconnects aircraft 4 from takeoff booster 6 after the acceleration of takeoff booster 6 is less than the acceleration of aircraft 4.

[0073] Takeoff assist device 6 brakes and decelerates, increasing the distance between itself and aircraft 4;

[0074] Aircraft 4 completed the takeoff operation according to the standard takeoff procedure.

[0075] The aircraft takeoff assist device design method of this application firstly increases the aircraft's acceleration during takeoff, shortens the takeoff field length, and improves the aircraft's takeoff performance. Secondly, increasing the takeoff acceleration does not increase the aircraft's empty weight or aerodynamic drag. Finally, it removes the design constraints on the airborne engine related to takeoff performance, allowing the airborne engine to be fully optimized according to the requirements of high-speed flight.

[0076] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A design method for an aircraft takeoff assist device, wherein the takeoff assist device (6) is installed on the lower part of an aircraft (4), characterized in that, The design method includes: designing a power module (8), a connection module, a control module (9), and a walking support module for the takeoff assist device (6), wherein the power module (8) is used to provide power to the takeoff assist device (6); the connection module is used to connect and disconnect the takeoff assist device (6) from the aircraft (4); the control module (9) is used to control the takeoff assist device (6); and the walking support module is used to support the walking of the takeoff assist device (6). The takeoff assist device (6) is used in the following manner: the aircraft (4) increases all throttle and releases the brakes at the takeoff line. The aircraft (4) accelerates and rolls; if an engine failure occurs before the critical engine failure speed, the pilot reduces all throttle, opens the spoilers, applies the brakes, and aborts takeoff; if no engine failure occurs before the critical engine failure speed, the pilot reduces the throttle of the takeoff booster (6) before lifting the nose wheel speed, and disconnects the aircraft (4) from the takeoff booster (6) after the acceleration of the takeoff booster (6) is less than the acceleration of the aircraft (4); the takeoff booster (6) brakes and decelerates, increasing the distance between itself and the aircraft (4); the aircraft (4) completes the takeoff operation according to the normal takeoff procedure.

2. The design method for an aircraft takeoff assist device according to claim 1, characterized in that, The aircraft (4) includes an aircraft central body (1), wings (2), airborne engines (3) and landing gear (5). The wings (2) include a left wing and a right wing, which are symmetrically arranged on the left and right sides of the aircraft central body (1). The airborne engines (3) include a left airborne engine and a right airborne engine, which are symmetrically arranged on the upper part of the aircraft central body (1). The landing gear (5) includes a front landing gear, a left rear landing gear and a right rear landing gear, which are arranged on the lower part of the aircraft central body (1).

3. The design method for an aircraft takeoff assist device according to claim 1, characterized in that, The power module (8) includes an aircraft engine, an intake unit, and an exhaust unit.

4. The design method for an aircraft takeoff assist device according to claim 3, characterized in that, The air intake unit ensures that the air entering the aircraft engine is free of impurities.

5. The design method for an aircraft takeoff assist device according to claim 4, characterized in that, The exhaust unit ensures that the jet stream from the aircraft engine does not damage the aircraft (4).

6. The design method for an aircraft takeoff assist device according to claim 1, characterized in that, The control module (9) includes: a driving direction control unit for controlling the driving direction of the takeoff assist device (6); a throttle position control unit for controlling the throttle position of the takeoff assist device (6); and a brake control unit for controlling the brake of the takeoff assist device (6).

7. The design method for an aircraft takeoff assist device according to claim 6, characterized in that, Once the takeoff assist device (6) establishes a connection with the aircraft (4), the aircraft (4) obtains the operating authority of the takeoff assist device (6).

8. The design method for an aircraft takeoff assist device according to claim 7, characterized in that, When the takeoff assist device (6) is disconnected from the aircraft (4), the takeoff assist device (6) regains its own operating authority.

9. The design method for an aircraft takeoff assist device according to claim 1, characterized in that, The walking support module includes: a support unit (12) connected to the takeoff assist device (6); a tire (10) installed at the bottom of the support unit (12); and a brake unit (11) installed on the tire (10).

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