A small aircraft hard landing detection system

Abstract

This utility model relates to the field of aircraft safety inspection technology, specifically disclosing a hard landing detection system for small aircraft, including a corresponding landing gear, a stroke detection mechanism, a controller, and a display. The landing gear has a sleeve and a shock absorber fitted inside the sleeve, and a piston rod that can move axially linearly within the sleeve. The stroke detection mechanism is used to detect the axial linear displacement data of the piston rod of the corresponding landing gear within the sleeve. The controller is used to acquire the detection data of each stroke detection mechanism and output it to the display. The display is arranged in the cockpit of the small aircraft. This utility model uses a position sensor to detect the axial linear displacement position of the landing gear piston rod within the sleeve. By detecting the out-of-bounds position signal of the piston rod during landing, the position sensor can effectively determine whether the aircraft has experienced a hard landing, providing guidance for maintenance personnel to inspect the aircraft. It is simple and easy to implement.

Description

Technical Field

[0001] This utility model relates to the field of aircraft safety detection technology, specifically a small aircraft hard landing detection system. Background Technology

[0002] A hard landing refers to a landing situation where the vertical acceleration of an aircraft exceeds design limits upon touchdown. This typically manifests as an excessive descent rate or an overly abrupt touchdown attitude. It can have significant impacts on the aircraft's structure, systems, and subsequent operations, including direct and hidden damage such as landing gear overload, wheel hub damage, brake assembly damage, landing gear-fuselage connection structure damage, fuselage damage, wing damage, and engine damage. Therefore, understanding hard landing situations is directly crucial to aircraft safety and flight safety.

[0003] Large passenger aircraft have sophisticated onboard flight data acquisition systems. By analyzing and calculating this flight data, they can effectively determine the likelihood of a hard landing. Of course, this is based on a complex flight data acquisition system, as well as specialized theoretical knowledge and accumulated experience.

[0004] However, small aircraft have a relatively simple design structure, especially trainer aircraft used for civil aviation flight training. They do not have the complex flight data acquisition system carried by large passenger aircraft, making it difficult to effectively grasp the situation of heavy landings, and relying entirely on the subjective experience and judgment of maintenance personnel. Utility Model Content

[0005] The technical objective of this utility model is to provide a simple small aircraft hard landing detection system that can effectively monitor the hard landing situation of aircraft, especially for small aircraft, particularly trainer aircraft used for civil aviation flight training, in view of the special characteristics of the above-mentioned aircraft hard landing and the shortcomings of the existing technology.

[0006] The technical objective of this utility model is achieved through the following technical solution: a small aircraft hard landing detection system, including the landing gear of a small aircraft;

[0007] The landing gear has a sleeve connected to a corresponding position on the fuselage, a shock absorber sleeve inside the sleeve, a piston rod that can move axially linearly inside the sleeve, and a wheel that can be rotatably mounted at the bottom end of the piston rod and located outside the sleeve.

[0008] The detection system also includes a stroke detection mechanism, a controller, and a display;

[0009] The stroke detection mechanism is used to detect the axial linear displacement data of the piston rod of the corresponding landing gear within the sleeve;

[0010] The controller is used to acquire the detection data of each stroke detection mechanism and output it to the display.

[0011] The displays are arranged in the cockpit of the small aircraft.

[0012] Furthermore, the stroke detection mechanism has at least one position sensor arranged on the sleeve for detecting the axial linear displacement position of the piston rod within the sleeve;

[0013] The position sensors are arranged at the maximum stroke position of the piston rod under normal landing conditions, and are used to detect the piston rod exceeding the limit position signal during landing and feed it back to the controller.

[0014] Furthermore, the stroke detection mechanism includes a piston support, a transmission arm, a sliding block, a sleeve support, and a position sensor;

[0015] The piston support is fixedly connected to the piston rod and extends radially outward, and is located outside the sleeve in both normal landing and hard landing conditions;

[0016] The sleeve support is fixedly connected to the sleeve and extends radially outward, with its upper and lower positions corresponding to the piston support.

[0017] The sleeve support has a linear groove with a strip structure in the vertical direction, and the linear stroke distance of the linear groove corresponds at least to the maximum stroke of the piston rod between the normal shutdown state and the hard landing state.

[0018] The lower end of the transmission arm is hinged to the piston support, and the upper end of the transmission arm is hinged to the sliding block, with the sliding block passing through the linear groove of the sleeve support. When the landing gear is in a normal stop state, the sliding block connected to the transmission arm is at the bottom of the linear groove; when the landing gear is in a hard landing state, the sliding block connected to the transmission arm is at the top of the linear groove.

[0019] The position sensor is arranged on the sleeve support, in the middle of the linear slide groove, and at the maximum stroke position of the piston rod in the normal landing state.

[0020] Alternatively, the stroke detection mechanism includes a piston support, a transmission arm one, a transmission arm two, a sliding block, a sleeve support, and a position sensor;

[0021] The piston support is fixedly connected to the piston rod and extends radially outward, and is located outside the sleeve in both normal landing and hard landing conditions;

[0022] The sleeve support is fixedly connected to the sleeve and extends radially outward, with its upper and lower positions corresponding to the piston support.

[0023] The sleeve support has an arc-shaped curved groove in the vertical direction, and the curved stroke distance of the curved groove corresponds at least to the maximum stroke of the piston rod between the normal shutdown state and the hard landing state.

[0024] The lower end of the first transmission arm is hinged to the piston support, and the upper end of the first transmission arm is hinged to the second transmission arm.

[0025] The upper end of the transmission arm two is hinged to the sliding block, and the sliding block is installed in the curved groove of the sleeve support; when the landing gear is in a normal stop state, the sliding block connected to the transmission arm two is at the bottom of the curved groove; when the landing gear is in a hard landing state, the sliding block connected to the transmission arm two is at the top of the curved groove.

[0026] The position sensor is arranged on the sleeve support, in the middle of the curved slide groove, and at the maximum stroke position of the piston rod in the normal landing state.

[0027] Furthermore, the position sensor is an optical position sensor or an ultrasonic position sensor.

[0028] Furthermore, the detection system includes the left main landing gear, the right main landing gear, and the nose landing gear of the small aircraft;

[0029] A corresponding travel detection mechanism is arranged on the left main landing gear;

[0030] A corresponding travel detection mechanism is arranged on the right main landing gear;

[0031] The front landing gear is equipped with a corresponding travel detection mechanism;

[0032] The travel detection mechanisms on each landing gear are independent of each other.

[0033] Furthermore, the displays are arranged in the area between the PFD display and the MFD display in the cockpit of the small aircraft.

[0034] Furthermore, the small aircraft is a trainer aircraft used for civil aviation flight training.

[0035] Furthermore, the small aircraft in question is a Cessna 172R.

[0036] The beneficial technical effects of this utility model are as follows: The above technical solution addresses the unique characteristics of aircraft hard landings and landing gear structures by using position sensors to detect the axial linear displacement of the landing gear piston rod within the sleeve. Specifically, position sensors are arranged at least at the maximum stroke position of the piston rod under normal landing conditions. These sensors detect any out-of-bounds position signals of the piston rod during landing, effectively determining whether a hard landing has occurred and providing guidance for maintenance personnel during aircraft repairs. The design of this technical solution is simple, can be modified for existing small aircraft, and is suitable for small aircraft, especially trainer aircraft used for civil aviation flight training. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of one structure of the landing gear of this utility model.

[0038] Figure 2 This is a schematic diagram of another structure of the landing gear of this utility model.

[0039] Figure 3 This is a block diagram illustrating the control principle of this utility model.

[0040] The symbols in the diagram have the following meanings: 1—Left main landing gear; 11—First position sensor; 2—Right main landing gear; 21—Second position sensor; 3—Front landing gear; 31—Third position sensor; 4—Controller; 5—Display; 6—Wheel; 7—Piston rod; 8—Sleeve; 9—Stroke detection mechanism; 91—Piston support; 92—Drive arm; 921—Drive arm one; 922—Drive arm two; 93—Sliding block; 94—Sleeve support; 95—Linear slide; 96—Position sensor; 97—Curved slide. Detailed Implementation

[0041] This utility model relates to the field of aircraft safety inspection technology, specifically a heavy landing detection system for small aircraft. The main technical solution of this utility model will be described in detail below with reference to several embodiments. Embodiment 1, in conjunction with the accompanying drawings, is... Figure 1 and Figure 3 The technical solution of this utility model will be clearly and thoroughly explained; Embodiment 2 is illustrated in conjunction with the accompanying drawings. Figure 2 and Figure 3 The technical solution of this utility model is clearly and in detail explained; although other embodiments are not shown in separate drawings, their main structure can still be referred to the drawings of Embodiment 1 or Embodiment 2.

[0042] It should be noted that the accompanying drawings of this utility model are schematic, and unnecessary details have been simplified to clarify the technical purpose of this utility model, so as to avoid obscuring the technical solution contributed by this utility model to the prior art. In addition, the expressions such as "about" and "basically" regarding quantity or fit relationship in the following text mean that reasonable assembly errors and processing errors are allowed in the industry, and do not literally describe absolute quantity or fit relationship.

[0043] Example 1

[0044] See Figure 1 and Figure 3 As shown, this utility model is a heavy landing detection system for small aircraft, especially civil aviation flight training aircraft, and more specifically for Cessna 172R aircraft. It includes the left main landing gear 1, the right main landing gear 2, the front landing gear 3, the controller 4, and the display 5 of the small aircraft.

[0045] The three landing gear sets mentioned above have the same hard landing detection structure, but they are independent of each other. The following description of the detection structure will not specifically distinguish which landing gear set it refers to.

[0046] See Figure 1 As shown, the landing gear has a sleeve 8 connected to a corresponding position on the aircraft fuselage (such as the front landing gear position, the left main landing gear position, or the right main landing gear position), a piston rod 7 fitted within the sleeve 8 with a shock-absorbing structure and capable of axial linear displacement within the sleeve 8, and a wheel 6 rotatably mounted at the bottom end of the piston rod 7 and located outside the sleeve 8. It is known that when the aircraft lands or is parked on the ground, the wheel 6 contacts the ground; to accommodate cushioning, the piston rod 7 is fitted within the sleeve 8 with a shock-absorbing structure.

[0047] Therefore, the axial linear displacement position of the piston rod 7 within the sleeve 8 will change due to the impact, specifically:

[0048] Assuming the aircraft is parked normally on the ground, the relative position of piston rod 7 within sleeve 8 is the normal parking zero position;

[0049] When an aircraft is impacted during a normal landing, the relative position of piston rod 7 within sleeve 8 will rise relative to the normal parking zero position. Therefore, the highest relative position of piston rod 7 within sleeve 8 during a normal landing is set as the critical position for normal landing.

[0050] When an aircraft experiences a hard landing on the ground, the relative position of piston rod 7 within sleeve 8 will shift upward relative to the normal landing critical position, thus exceeding the normal landing critical position. It is evident that the normal landing critical position is the critical point for determining whether an aircraft has experienced a hard landing. By monitoring the relative position of piston rod 7 at this position, it is possible to determine whether the aircraft has experienced a hard landing.

[0051] Based on the aforementioned positional change of the piston rod 7 within the sleeve 8 due to impact, the stroke of the piston rod 7 within the sleeve 8 can be categorized as follows:

[0052] The travel range between the normal parking zero position and the normal landing critical position is the normal landing indication zone. If the axial relative position of the piston rod 7 in the sleeve 8 is within the normal landing indication zone, it indicates that it has not been subjected to a heavy landing impact and is relatively safe in the case of a heavy landing. Other routine or necessary checks can be performed during the aircraft inspection.

[0053] The travel range above the normal landing critical position is the hard landing indication zone. If the axial relative position of the piston rod 7 in the sleeve 8 is within the hard landing indication zone, it indicates that the aircraft has been subjected to a hard landing impact. During the aircraft inspection, the parts damaged by the hard landing need to be carefully inspected.

[0054] In order to determine the axial relative position of the piston rod 7 of the landing gear within the sleeve 8, a stroke detection mechanism 9 is provided on the basis of the landing gear structure. The stroke detection mechanism 9 has a piston support 91, a transmission arm 92, a sliding block 93, a sleeve support 94, and a position sensor 96.

[0055] Specifically, the piston support 91 is fixedly connected to the piston rod 7 and extends radially outward. The connection position of the piston support 91 on the piston rod 7 is always outside the sleeve 8, that is, whether in normal landing or hard landing, it is outside the sleeve 8 and will not interfere with the axial linear displacement of the piston rod 7 inside the sleeve 8.

[0056] The sleeve support 94 is fixedly connected to the sleeve 8 and extends radially outward, forming a vertically corresponding fit with the piston support 91 below. A linear groove 95 with a strip-shaped structure is formed on the vertical direction of the sleeve support 94. The direction of the linear groove 95 is consistent with the direction of the piston rod 7 within the sleeve 8. Moreover, the linear stroke distance of the linear groove 95 is slightly greater than the maximum stroke of the piston rod 7 between the normal stop state and the hard landing state—that is, the stroke distance between the normal parking zero position and the highest position of the hard landing. Based on the aforementioned positional changes of the piston rod 7 within the sleeve 8 due to impact, the bottom of the aforementioned linear groove 95 is the normal parking zero position. Using the normal parking zero position as a reference, the normal landing critical position is set at the middle position of the linear groove 95.

[0057] The lower end of the transmission arm 92 is hinged to the piston support 91 via a hinge shaft, and the upper end of the transmission arm 92 is hinged to the sliding block 93 via a hinge shaft. The sliding block 93 is installed in the linear groove 95 of the sleeve support 94 and can slide up and down along the linear groove 95 under the drive of the transmission arm 92.

[0058] When the landing gear is in the normal parking state, the sliding block 93 connected to the drive arm 92 is at the bottom position of the aforementioned linear slide groove 95 - that is, the normal parking zero position.

[0059] When the landing gear is in the normal landing state, the sliding block 93 connected to the drive arm 92 is in the normal landing indication area of ​​the aforementioned linear slide 95.

[0060] When the landing gear is in a hard landing state, the sliding block 93 connected to the drive arm 92 passes the normal landing critical position and is at the top position of the aforementioned linear slide 95 - that is, the aforementioned hard landing indication area.

[0061] The position sensor 96 is an optical position sensor or an ultrasonic position sensor. The position sensor 96 is arranged on the aforementioned sleeve support 94, located at the normal landing critical position in the middle of the aforementioned linear slide 95, that is, at the maximum stroke position of the piston rod 7 under normal landing conditions. The operating power of the position sensor 96 is drawn from the aircraft power supply system nearby, or directly provided by the controller.

[0062] The stroke detection mechanism 9, composed of the above-mentioned structure, detects the axial linear displacement data—that is, the position signal—of the piston rod 7 of the landing gear (such as the left main landing gear 1, the right main landing gear 2, or the front landing gear 3) within the sleeve 8. The detection result is fed back to the controller 4, which converts the detection signal from analog to digital and outputs it to the display 5. The display 5 is located in the cockpit of the small aircraft for the pilot to view and control intuitively.

[0063] Since this invention is particularly suitable for civil aviation flight training aircraft, the intuitive viewing of the display 5 should cater to both trainees and instructors. Therefore, the display 5 is preferably located in the area between the PFD display screen and the MFD display screen in the cockpit of a small aircraft, and can be directly fixed by the panel fixing screws in this area.

[0064] like Figure 3As shown, to monitor the landing gear status of each landing gear of a small aircraft, the stroke detection mechanism 9, as described above, is configured for each landing gear. Specifically, one set of stroke detection mechanisms 9 is configured for the left main landing gear 1, one set for the right main landing gear 2, and one set for the front landing gear 3. These three sets of stroke detection mechanisms 9 share the same controller 4, thus differentiating the position sensors of the stroke detection mechanisms 9 for different landing gears. The position sensor 96 of the stroke detection mechanism 9 configured for the left main landing gear 1 is defined as the first position sensor 11 in the system; the position sensor 96 of the stroke detection mechanism 9 configured for the right main landing gear 2 is defined as the second position sensor 21 in the system; and the position sensor 96 of the stroke detection mechanism 9 configured for the front landing gear 3 is defined as the third position sensor 31 in the system. They respectively feed back corresponding detection signals to the controller 4.

[0065] In other words, the left main landing gear 1 is equipped with a corresponding travel detection mechanism 9, the right main landing gear 2 is equipped with a corresponding travel detection mechanism 9, and the front landing gear 3 is equipped with a corresponding travel detection mechanism 9, so that the travel detection mechanisms 9 on each landing gear are formed independently.

[0066] Example 2

[0067] The rest of the content of this embodiment is the same as that of embodiment 1, except that:

[0068] See Figure 2 As shown, the stroke detection mechanism 9 has a piston support 91, a transmission arm 1 921, a transmission arm 2 922, a sliding block 93, a sleeve support 94, and a position sensor 96.

[0069] Among them, the piston support 91 is fixedly connected to the piston rod 7 and extends radially outward, and is located outside the sleeve 8 in both normal landing and hard landing states;

[0070] The sleeve support 94 is fixedly connected to the sleeve 8 and extends radially outward, with its upper and lower positions corresponding to the piston support 91;

[0071] The sleeve support 94 has an arc-shaped curved groove 97 in the vertical direction, and the curved stroke distance of the curved groove 97 is slightly greater than the maximum stroke of the piston rod 7 between the normal shutdown state and the hard landing state.

[0072] The lower end of transmission arm 921 is hinged to piston support 91, and the upper end of transmission arm 921 is hinged to transmission arm 922.

[0073] The upper end of the transmission arm 922 is hinged to the sliding block 93, and the sliding block 93 is installed in the curved groove 97 of the sleeve support 94. When the landing gear is in the normal parking state, the sliding block 93 connected to the transmission arm 922 is at the bottom of the curved groove 97 - that is, the normal parking zero position. When the landing gear is in the normal landing state, the sliding block 93 connected to the transmission arm 922 is in the normal landing indication area of ​​the curved groove 97. When the landing gear is in the hard landing state, the sliding block 93 connected to the transmission arm 922 crosses the normal landing critical position and is at the top position of the curved groove 97 - that is, the hard landing indication area.

[0074] The position sensor 96 is arranged on the sleeve support 94, in the middle of the curved slide 97, at the normal landing critical position in the middle of the curved slide 97, that is, at the maximum stroke position of the piston rod 7 in the normal landing state.

[0075] Example 3

[0076] The rest of the content of this embodiment is the same as that of embodiment 1 or embodiment 2, except that:

[0077] The position sensors of each travel detection mechanism are designed in multiple ways. These position sensors are arranged sequentially along the travel height in the hard landing indication area, with the normal landing critical position as the reference. By using the position signals detected by different position sensors at different travel heights, the magnitude of the impact force during hard landing can be directly determined. The closer to the normal landing critical position, the smaller the impact force, and vice versa.

[0078] The above embodiments are only used to illustrate the present invention and are not intended to limit it.

[0079] Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications can still be made to the above embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the present invention.

Claims

1. A heavy landing detection system for a small aircraft, including the landing gear of a small aircraft; The landing gear has a sleeve (8) connected to the corresponding position of the fuselage, a shock absorber sleeve inside the sleeve (8) and a piston rod (7) that can be axially linearly displaced inside the sleeve (8), and a wheel (6) that can be rotatably mounted at the bottom end of the piston rod (7) and located outside the sleeve (8). Its features are: The detection system also includes a stroke detection mechanism (9), a controller (4), and a display (5); The stroke detection mechanism (9) is used to detect the axial linear displacement data of the piston rod (7) of the corresponding landing gear in the sleeve (8); The controller (4) is used to acquire the detection data of each stroke detection mechanism (9) and output it to the display (5); The displays (5) are arranged in the cockpit of the small aircraft.

2. The small aircraft hard landing detection system according to claim 1, characterized in that: The stroke detection mechanism (9) has at least one position sensor (96) arranged on the sleeve (8) for detecting the axial linear displacement position of the piston rod (7) within the sleeve (8). The position sensor (96) is arranged at the maximum stroke position of the piston rod (7) under normal landing conditions, and is used to detect the out-of-bounds position signal of the piston rod (7) during landing and feed it back to the controller (4).

3. The small aircraft hard landing detection system according to claim 2, characterized in that: The stroke detection mechanism (9) has a piston support (91), a transmission arm (92), a sliding block (93), a sleeve support (94), and a position sensor (96). The piston support (91) is fixedly connected to the piston rod (7) and extends radially outward, and is located outside the sleeve (8) in both normal landing and hard landing states; The sleeve support (94) is fixedly connected to the sleeve (8) and extends radially outward, with its upper and lower positions corresponding to the piston support (91). The sleeve support (94) has a linear groove (95) with a strip structure in the vertical direction, and the linear stroke distance of the linear groove (95) corresponds at least to the maximum stroke of the piston rod (7) between the normal shutdown state and the hard landing state. The lower end of the transmission arm (92) is hinged to the piston support (91), and the upper end of the transmission arm (92) is hinged to the sliding block (93). The sliding block (93) is inserted into the linear groove (95) of the sleeve support (94). When the landing gear is in a normal stop state, the sliding block (93) connected to the transmission arm (92) is at the bottom of the linear groove (95). When the landing gear is in a hard landing state, the sliding block (93) connected to the transmission arm (92) is at the top of the linear groove (95). The position sensor (96) is arranged on the sleeve support (94), in the middle of the linear slide (95), and at the maximum stroke position of the piston rod (7) in the normal landing state.

4. The small aircraft hard landing detection system according to claim 2, characterized in that: The stroke detection mechanism (9) includes a piston support (91), a transmission arm one (921), a transmission arm two (922), a sliding block (93), a sleeve support (94), and a position sensor (96). The piston support (91) is fixedly connected to the piston rod (7) and extends radially outward, and is located outside the sleeve (8) in both normal landing and hard landing states; The sleeve support (94) is fixedly connected to the sleeve (8) and extends radially outward, with its upper and lower positions corresponding to the piston support (91). The sleeve support (94) has an arc-shaped curved groove (97) in the vertical direction, and the curved stroke distance of the curved groove (97) corresponds at least to the maximum stroke of the piston rod (7) between the normal shutdown state and the hard landing state. The lower end of the first transmission arm (921) is hinged to the piston support (91), and the upper end of the first transmission arm (921) is hinged to the second transmission arm (922). The upper end of the transmission arm two (922) is hinged to the sliding block (93), and the sliding block (93) is inserted into the curved groove (97) of the sleeve support (94); when the landing gear is in a normal stop state, the sliding block (93) connected to the transmission arm two (922) is at the bottom of the curved groove (97); when the landing gear is in a hard landing state, the sliding block (93) connected to the transmission arm two (922) is at the top of the curved groove (97); The position sensor (96) is arranged on the sleeve support (94), in the middle of the curved slide (97), and at the maximum stroke position of the piston rod (7) in the normal landing state.

5. The small aircraft hard landing detection system according to claim 2, 3 or 4, characterized in that: The position sensor (96) is an optical position sensor or an ultrasonic position sensor.

6. The small aircraft hard landing detection system according to claim 1, characterized in that: The detection system includes the left main landing gear (1), the right main landing gear (2) and the front landing gear (3) of the small aircraft. The left main landing gear (1) is equipped with a corresponding travel detection mechanism (9); The right main landing gear (2) is equipped with a corresponding stroke detection mechanism (9); The front landing gear (3) is equipped with a corresponding travel detection mechanism (9); The travel detection mechanisms (9) on each landing gear are independent of each other.

7. The small aircraft hard landing detection system according to claim 1, characterized in that: The display (5) is located in the area between the PFD display screen and the MFD display screen in the cockpit of the small aircraft.

8. The small aircraft hard landing detection system according to claim 1, 6 or 7, characterized in that: The small aircraft in question is a training aircraft used for civil aviation flight training.

9. The small aircraft hard landing detection system according to claim 8, characterized in that: The small aircraft in question is a Cessna 172R.

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