A folding tail boom structure for a single rotor tail rotor helicopter

Abstract

This application relates to the field of aircraft structural design technology, and more particularly to a folding tail boom structure for a single-rotor helicopter with a tail rotor, including a fuselage, a tail boom, and a folding assembly disposed at the connection between the fuselage and the tail boom. The folding assembly includes a front folding frame and a rear folding frame, with the front folding frame fixedly connected to the tail of the fuselage and the rear folding frame fixedly connected to the front end of the tail boom. The front and rear folding frames are rotatably connected by at least one set of shoulder screws, forming a folding rotating pair. This invention provides a porous oxide film layer formed by phosphoric acid anodizing at the connection interface between the front and rear folding frames and the fuselage / tail boom, combined with structural adhesive bonding, riveting mechanical fixation, and end face screw locking, forming an interconnected four-fold fixing structure. At the same time, the porous oxide film layer significantly improves the roughness and chemical activity of the bonding interface, greatly enhancing the bonding strength and effectively solving the problem of loosening of traditional quick-release pin connections under heavy loads.

Description

Technical Field

[0001] This application relates to the field of aircraft structural design technology, and in particular to a folding tail boom structure for a single-rotor helicopter with a tail rotor. Background Technology

[0002] Single-rotor helicopters with tail rotors are widely used in forest firefighting, emergency rescue, and material delivery due to their simple aerodynamic layout and excellent hovering performance. The tail boom, as a key structural component connecting the fuselage and tail rotor, bears multiple functions, including transmitting tail rotor counter-torque, bearing aerodynamic loads, and supporting tail rotor installation. However, traditional tail booms often adopt a one-piece long beam structure, resulting in a large overall length and significant shortcomings in transportation, storage, and rapid deployment: firstly, long tail booms require large transport vehicles or dedicated hangars, increasing operating costs and space limitations; secondly, in emergency scenarios, helicopters need rapid relocation and deployment, and the inability to quickly disassemble or fold the tail boom severely impacts response efficiency.

[0003] To address these issues, the industry has proposed foldable tail boom solutions. For example, Chinese patent CN222005385U discloses a foldable tail boom quick-release support structure for a single-rotor helicopter, which uses support rods and ball bearing quick-release pins to achieve rapid assembly, disassembly, and folding of the tail boom. However, this solution is mainly suitable for small and lightweight UAVs, and its connection methods lack effective chemical interlocking and mechanical anchoring, resulting in significant issues with pin hole wear and loose connections, leading to insufficient durability. Summary of the Invention

[0004] This application provides a folding tail boom structure for a single-rotor helicopter with a tail rotor, which solves the technical problems of existing tail boom structures for ton-class single-rotor helicopters, such as large storage and transportation space, difficulty in rapid deployment, and prominent contradiction between structural strength and weight.

[0005] This application provides a folding tail boom structure for a single-rotor helicopter with a tail rotor, including a fuselage, a tail boom, and a folding assembly disposed at the connection between the fuselage and the tail boom. The folding assembly includes a front folding frame and a rear folding frame. The front folding frame is fixedly connected to the rear of the fuselage, and the rear folding frame is fixedly connected to the front end of the tail beam. The front folding frame and the rear folding frame are rotatably connected by at least one set of shoulder screws to form a folding rotary pair; After the connection interface between the front folding frame and the rear folding frame and the fuselage / tail beam is surface treated to form a porous oxide film layer, it is then bonded and fixed to the fuselage / tail beam with structural adhesive. The connection interface is also provided with multiple rivets and / or end face screws.

[0006] Preferably, both the front folding frame and the rear folding frame are made of aerospace-grade aluminum alloy; the porous oxide film layer is generated by phosphoric acid anodizing of the front folding frame and the rear folding frame, and the film layer thickness is 8-12μm.

[0007] Preferably, both the front folding frame and the rear folding frame are integrated hollow shell structures with a U-shaped notch at the top, and their overall outline is horseshoe-shaped to fit the curved surface of the fuselage. The outer periphery of both the front and rear folding frames is bent backward to form a sleeve ring perpendicular to its axis. The sidewall of the rear folding frame is provided with several weight-reducing holes circumferentially along its outline.

[0008] Preferably, the front folding frame is sleeved on the outside of the rear of the fuselage via the sleeve ring, and the inner end face of the front folding frame abuts against the cross-section of the rear of the fuselage; The rear folding frame is embedded in the inner side of the front end of the tail beam through the sleeve ring, and the inner end face of the rear folding frame abuts against the end face of the front end of the tail beam. The end faces of the front and rear folding frames are locked to the end faces of the rear of the fuselage or the front end of the tail beam by end face screws.

[0009] Preferably, the ferrule is fixedly connected to the fuselage / tail beam by a plurality of rivets arranged in a circumferential array; The rivets are arranged in a staggered pattern at a 45° angle on the outside of the sleeve ring. The rivets are made of titanium alloy, and an anti-corrosion gasket is provided between the rivets and the porous oxide film layer.

[0010] Preferably, there are two sets of shoulder screws, which are symmetrically arranged on opposite sides of the front folding frame and the rear folding frame. The shoulder screws on one side are detachable, while those on the other side are fixed, forming a single-sided rotational folding structure.

[0011] Preferably, one of the front folding frame and the rear folding frame is provided with an insertion flange, and the other is provided with a corresponding interlayer flange. The insertion flange is inserted into the interlayer flange in the flight state, and the shoulder screw is provided in the insertion flange and the interlayer flange.

[0012] Preferably, the system also includes flight-state locking screws, which are in four groups and symmetrically distributed around the front folding frame and the rear folding frame. The front folding frame and the rear folding frame are respectively provided with locking bosses for installing the flight-state locking screws.

[0013] Preferably, the body is provided with a tail beam fixing support for supporting the tail beam in the folded state, and the tail beam fixing support is provided with a buffer pad.

[0014] Preferably, the structural adhesive is an epoxy resin structural adhesive, the coating thickness is 0.2-0.5 mm, the curing temperature is room temperature, and the curing time is greater than or equal to 24 hours.

[0015] The beneficial effects of this application are as follows: The folding tail boom structure of the single-rotor helicopter with tail rotor of this application is constructed by setting a porous oxide film layer formed by phosphoric acid anodizing at the connection interface between the front folding frame and the rear folding frame and the fuselage / tail boom. Combined with structural adhesive bonding, mechanical fixing with rivets and end face screw locking, a four-fold fixing structure is formed. At the same time, the setting of the porous oxide film layer greatly improves the roughness and chemical activity of the bonding interface, which greatly improves the bonding strength compared with untreated aluminum alloy material, effectively solving the problem of loosening of traditional quick-release pin connections under heavy load.

[0016] Furthermore, a rotating pair is formed by the shoulder screws, which, together with the flight state locking screws, achieves dual-state locking. When folding, it is only necessary to remove the flight state locking screws and loosen one side of the shoulder screws to achieve 90° rotation folding, thus enabling rapid folding of the tail rotor. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 A planar schematic diagram of the folding tail boom structure of a single-rotor helicopter with a tail rotor provided in an embodiment of this application; Figure 2 This is a three-dimensional structural diagram of the folding component in this application; Figure 3 This is a schematic diagram of the installation structure of the front folding frame at the rear end of the fuselage in this application; Figure 4 This is a schematic diagram of the installation structure of the rear folding frame at the front end of the tail beam in this application; Figure 5 This is a schematic diagram of the mounting structure of the shoulder screw in the folding assembly in this application; Figure 6 This is a schematic diagram of the planar structure of the tail beam in the folded state in an embodiment of this application.

[0019] Figure label: 1. Body; 2. Tail beam; 3. Folding assembly; 31. Front folding frame; 32. Rear folding frame; 33. Socket ring; 34. Weight reduction hole; 35. Insertion flange; 36. Interlayer flange; 37. Locking boss; 4. Shoulder screw; 5. Tail beam fixing support; 6. Rivet; 7. End face screw. Detailed Implementation

[0020] The technical solutions of this application will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0021] The following is combined with Figures 1-6 This paper describes the folding tail boom structure of a single-rotor helicopter with a tail rotor provided in the embodiments of this application. The following example illustrates the application of this structure to the FWH-1500 light helicopter (maximum takeoff weight 1200kg). Its core load-bearing components are the front and rear folding frames made of aerospace-grade aluminum alloy. The supporting connecting components include titanium alloy rivets, hexagonal head screws, and anti-corrosion washers. The connecting medium is epoxy structural adhesive, and the surface of the aluminum alloy folding frame is coated with a phosphoric acid anodized oxide film. The material selection of each component is matched to the heavy load requirements of ton-class helicopters and the environmental adaptability requirements of aviation scenarios. By selecting aerospace-grade aluminum alloy that balances lightweight structure and high mechanical strength, it can effectively bear the counter-torque generated by the tail rotor and the aerodynamic load during flight. The titanium alloy rivets and hexagonal head screws have excellent shear and tensile strength and strong corrosion resistance, which can effectively adapt to the complex operating environment of helicopters.

[0022] Reference Figures 1-5 As shown in the embodiment of this application, the folding tail boom structure of a single-rotor helicopter with a tail boom is applied to the FWH-1500-ton class unmanned helicopter. It mainly includes a fuselage 1, a tail boom 2, and a folding assembly 3 disposed at the connection between the fuselage 1 and the tail boom 2, wherein: The folding assembly 3 includes a front folding frame 31 and a rear folding frame 32. The front folding frame 31 is fixedly connected to the tail of the fuselage 1, and the rear folding frame 32 is fixedly connected to the front end of the tail boom 2. Both the front folding frame 31 and the rear folding frame 32 are made of aerospace-grade aluminum alloy and are optimized according to the load transmission path of the fuselage. The stress areas are thickened, and the non-stress areas are designed with lightweight hollowing out to achieve the design goal of "strong load-bearing capacity and light weight".

[0023] Specifically, such as Figure 2As shown, both the front folding frame 31 and the rear folding frame 32 are integrated hollow shell structures with a U-shaped notch at the top. Their overall outline is horseshoe-shaped to fit the curved surface of the fuselage. The U-shaped notch not only reduces weight but also provides clearance for the helicopter's original drive shaft. The outer periphery of both the front folding frame 31 and the rear folding frame 32 is bent backward to form a sleeve ring 33 perpendicular to its axial direction, that is, the sleeve ring 33 extends along the longitudinal direction of the fuselage. The side wall of the rear folding frame 32 is provided with several weight-reducing holes 34 circumferentially along its outline. While achieving component weight reduction, it can also increase the overall amount of structural adhesive applied and the overall contact area between the structural adhesive and the rear folding frame, further enhancing its adhesion. In addition, in this embodiment, several end face weight-reducing holes are also provided at the end faces of the front folding frame 31 and the rear folding frame 32 to further reduce their own weight burden.

[0024] By using aerospace-grade aluminum alloy for the folding frame and employing lightweight designs such as weight-reducing holes and U-shaped notches, the overall weight is appropriately reduced while ensuring final strength. The thickness of the rear folding frame is less than that of the front folding frame, further optimizing the weight at the load-bearing end and reducing the burden on the folding pair.

[0025] In terms of assembly relationships, such as Figure 3 and Figure 4 As shown, the front folding frame 31 is fitted onto the outer side of the tail section of the fuselage 1 via a connecting ring 33, and the inner end face of the front folding frame 31 abuts against the cross-section of the tail section of the fuselage 1; the rear folding frame 32 is embedded into the inner side of the front end of the tail beam 2 via a connecting ring 33, and the inner end face of the rear folding frame 32 abuts against the end face of the front end of the tail beam 2. To ensure balance and reduce the load on the connection, the overall thickness of the rear folding frame 32 is less than the overall thickness of the front folding frame 31, thereby reducing the overall weight of the tail beam end, which bears the load, and thus reducing the load on the folding assembly.

[0026] In some specific embodiments, to achieve a high-strength connection, this embodiment employs a "quadruple fixation" technology. A porous oxide film layer is formed at the connection interface between the front and rear folding frames and the fuselage / tail beam after surface treatment. Specifically, the aluminum alloy folding frames undergo phosphoric acid anodizing treatment to generate a porous oxide film layer with a thickness of 8-12 μm. This forms a porous oxide film on the corresponding surfaces of the front and rear folding frames, enhancing the mechanical and chemical bonding with the structural adhesive. Subsequently, the frames are bonded and fixed to the fuselage / tail beam using structural adhesive, preferably epoxy resin. The adhesive thickness is 0.2-0.5 mm, the curing temperature is room temperature, and the curing time is greater than or equal to 24 hours.

[0027] The preparation of this phosphoric acid anodized film is achieved through a standardized process, which sequentially completes substrate degreasing, pickling, phosphoric acid anodizing, and post-treatment to ensure the uniformity of the film's pores, structural stability, and adhesive compatibility with epoxy structural adhesive. Specifically, the resulting oxide film has a thickness of 8-12 μm and is uniformly porous, which can significantly improve the surface roughness and surface chemical activity of the bonding surface of the folding frame. This allows the epoxy structural adhesive to fully fill the pores of the film and chemically bond with it, significantly improving its adhesive strength compared to aluminum alloy folding frames that have not undergone anodizing treatment.

[0028] In addition to the adhesive bonding, multiple rivets 6 and end face screws 7 are arranged at the connection interface. The sleeve ring 33 is fixedly connected to the fuselage / tail beam by several rivets 6 arranged in a circumferential array; the rivets 6 are arranged at a 45° angle and staggered on the outside of the sleeve ring 33. The rivets 6 are made of titanium alloy, and anti-corrosion washers are provided between the rivets 6 and the porous oxide film layer to avoid galvanic corrosion between the two; the end faces of the front folding frame 31 and the rear folding frame 32 are locked to the end faces of the tail of the fuselage 1 or the front end of the tail beam 2 by end face screws 7. This constitutes a quadruple fixing structure combining anodized film layer, adhesive bonding, rivets and end face screws, which effectively ensures the connection reliability under heavy loads.

[0029] By applying a porous oxide film layer formed by phosphoric acid anodizing at the connection interface between the front and rear folding frames and the fuselage / tail boom, combined with structural adhesive bonding, mechanical fixing with rivets, and end face screw locking, a four-fold fixing structure of "anodized film layer + adhesive bonding + rivets + end face screws" is formed. At the same time, the porous oxide film layer significantly improves the roughness and chemical activity of the bonding interface, making the bonding strength much higher than that of untreated aluminum alloy material. This effectively solves the problem of traditional quick-release pin connections being prone to loosening under heavy loads, thus meeting the load requirements of ton-class helicopters.

[0030] Specifically, the overall process of anodizing and post-treatment is as follows: Substrate cleaning: The aluminum alloy substrate of the folding frame is degreased using an alkaline degreasing agent at a temperature of 50°C for 10 minutes. It is then pickled with 15% phosphoric acid at room temperature to remove surface oil and oxide scale. Phosphoric acid anodizing: The cleaned folded frame is placed in a phosphoric acid electrolyte with a concentration of 20% and a temperature of 25℃. The current density is controlled at 1.5A / dm², and electrolysis is carried out for 20 minutes to generate a porous oxide film with a thickness of 8-12μm. Post-treatment: After rinsing with deionized water at 0.3 MPa pressure, the oxide film is sealed in boiling water for 15 minutes to improve its stability and ensure adhesion compatibility.

[0031] Bonding and bonding: Apply epoxy structural adhesive (approximately 0.2-0.5 mm thick) to the bonding surface of the anodized folding frame, position and bond it to the composite body using tooling, and cure at room temperature for 24 hours to form an adhesive layer; Rivet fixing: Rivets 6 are arranged in a staggered pattern on the outside of the folding frame at a spacing of 50mm and an angle of 45°. Mechanical reinforcement is achieved through a press riveting process. Anti-corrosion gaskets are used to isolate the contact surface between rivets 6 and oxide film to avoid galvanic corrosion. End face fixing: Through the pre-drilled screw holes on the end face, use hexagonal screws as end face screws 7 to lock the two folding frames to the main structure of the machine body, ensuring that the end faces fit together without gaps.

[0032] The excellent corrosion resistance of the phosphate anodized film, combined with titanium alloy rivets and anti-corrosion washers, can effectively isolate galvanic corrosion and adapt to harsh environments such as high altitude, cold, and high salt spray.

[0033] In some specific embodiments, such as Figure 5 As shown, the front folding frame 31 and the rear folding frame 32 are rotatably connected by two sets of shoulder screws 4, forming a folding rotary joint. The two sets of shoulder screws 4 are symmetrically arranged on opposite sides of the front folding frame 31 and the rear folding frame 32. One side of the shoulder screw 4 is detachable, and the other side is fixed, forming a single-sided rotating folding structure. During the folding operation, the fixed shoulder screw on one side serves as the rotation fulcrum, and the detachable side serves as the opening and closing end, rotating around the rotation fulcrum to fold the tail beam 2 and the fuselage 1.

[0034] One of the front folding frame 31 and the rear folding frame 32 is provided with an insertion flange 35, and the other is provided with a corresponding interlayer flange 36. In flight mode, the insertion flange 35 is inserted into the interlayer flange 36, and shoulder screws 4 are located in both the insertion flange 35 and the interlayer flange 36. This insertion structure enhances the structural rigidity and alignment in the unfolded state, achieving precise alignment and ensuring the coaxiality of the tail boom after folding.

[0035] To ensure flight safety, the structure also includes flight-state locking screws. There are four sets of flight-state locking screws, symmetrically distributed around the front folding frame 31 and the rear folding frame 32. The front folding frame 31 and the rear folding frame 32 are each provided with a locking boss 37 for installing the flight-state locking screws. During flight, the four flight-state locking screws are installed and tightened to the specified torque to achieve gapless fixation. During folding, the flight-state locking screws are removed, and the shoulder screw 4 on the detachable side is loosened, allowing the tail beam to rotate 90° around the fixed-side shoulder screw, achieving folding and storage.

[0036] A rotating pair is formed by the shoulder screw 4, which, together with the flight state locking screw, achieves dual-state locking. When folding, simply remove the flight state locking screw and loosen one side of the shoulder screw 4 to achieve 90° rotation folding, enabling rapid folding of the tail rotor. At the same time, the front folding frame and the rear folding frame achieve precise alignment through the cooperation of the insertion flange and the interlayer flange, and achieve gapless fixation through the flight state locking screw and the locking boss, eliminating displacement caused by flight vibration and ensuring the stability of tail rotor anti-torque transmission and flight safety.

[0037] In some specific embodiments, such as Figure 6 As shown, the fuselage 1 is provided with a tail beam fixing support 5 for supporting the tail beam 2 in the folded state. The tail beam fixing support 5 is provided with a buffer pad for absorbing vibration and impact during transportation.

[0038] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, 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, and therefore should not be construed as a limitation of this application.

[0039] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0040] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between components; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0041] In this application, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0042] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A folding tail boom structure for a single-rotor helicopter with a tail rotor, comprising a fuselage (1), a tail boom (2), and a folding assembly (3) disposed at the connection between the fuselage (1) and the tail boom (2), characterized in that: The folding assembly (3) includes a front folding frame (31) and a rear folding frame (32). The front folding frame (31) is fixedly connected to the tail of the fuselage (1), and the rear folding frame (32) is fixedly connected to the front end of the tail beam (2). The front folding frame (31) and the rear folding frame (32) are rotatably connected by at least one set of shoulder screws (4) to form a folding rotary pair; After the connection interface between the front folding frame (31) and the rear folding frame (32) and the fuselage / tail beam is surface treated to form a porous oxide film layer, it is bonded and fixed to the fuselage / tail beam by structural adhesive.

2. The folding tail boom structure of a single-rotor helicopter with a tail rotor according to claim 1, characterized in that, Both the front folding frame (31) and the rear folding frame (32) are made of aerospace-grade aluminum alloy. The porous oxide film is generated by phosphoric acid anodizing of the front folded frame (31) and the rear folded frame (32), and the film thickness is 8-12 μm.

3. The folding tail boom structure of a single-rotor helicopter with a tail rotor according to claim 2, characterized in that, The front folding frame (31) and the rear folding frame (32) are both integrated hollow shell structures with a U-shaped notch at the top, and their overall outline is horseshoe-shaped to fit the curved surface of the fuselage. The outer periphery of both the front folding frame (31) and the rear folding frame (32) is bent backward to form a sleeve ring (33) perpendicular to its axis; The sidewall of the rear folding frame (32) is provided with several weight-reducing holes (34) along its outline.

4. The folding tail boom structure of a single-rotor helicopter with a tail rotor according to claim 3, characterized in that, The front folding frame (31) is sleeved on the outer side of the rear of the fuselage (1) through the sleeve ring (33), and the inner end face of the front folding frame (31) abuts against the cross section of the rear of the fuselage (1); The rear folding frame (32) is embedded in the inner side of the front end of the tail beam (2) through the sleeve ring (33), and the inner end face of the rear folding frame (32) abuts against the end face of the front end of the tail beam (2); The end faces of the front folding frame (31) and the rear folding frame (32) are locked to the end face of the tail of the fuselage (1) or the front end of the tail beam (2) by end face screws (7).

5. The folding tail boom structure of a single-rotor helicopter with a tail rotor according to claim 4, characterized in that, The sleeve ring (33) is fixedly connected to the fuselage / tail beam by a number of rivets (6) arranged in a circumferential array; The rivets (6) are arranged in an alternating pattern at a 45° angle on the outside of the sleeve ring (33). The rivets (6) are made of titanium alloy and an anti-corrosion gasket is provided between the rivets (6) and the porous oxide film layer.

6. The folding tail boom structure of a single-rotor helicopter with a tail rotor according to claim 5, characterized in that, The shoulder screws (4) are in two sets, and the two sets of shoulder screws (4) are symmetrically arranged on opposite sides of the front folding frame (31) and the rear folding frame (32). The shoulder screws (4) on one side are detachable, and the other side is fixed, forming a single-sided rotating folding structure.

7. The folding tail boom structure of a single-rotor helicopter with a tail rotor according to claim 6, characterized in that, One of the front folding frame (31) and the rear folding frame (32) is provided with an insertion flange (35), and the other is provided with a corresponding interlayer flange (36). The insertion flange (35) is inserted into the interlayer flange (36) in the flight state, and the shoulder screw (4) is provided in the insertion flange (35) and the interlayer flange (36).

8. The folding tail boom structure of a single-rotor helicopter with a tail rotor according to claim 1, characterized in that, It also includes flight state locking screws, which are in four groups and symmetrically distributed around the front folding frame (31) and the rear folding frame (32). The front folding frame (31) and the rear folding frame (32) are respectively provided with locking bosses (37) for installing the flight state locking screws.

9. The folding tail boom structure of a single-rotor helicopter with a tail rotor according to claim 1, characterized in that, The fuselage (1) is provided with a tail beam fixing support (5) for supporting the tail beam (2) in the folded state, and the tail beam fixing support (5) is provided with a buffer pad.

10. The folding tail boom structure of a single-rotor helicopter with a tail rotor according to claim 1, characterized in that, The structural adhesive is an epoxy resin structural adhesive with a coating thickness of 0.2-0.5 mm, a curing temperature of room temperature, and a curing time of ≥24 h.

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