Hover-capable aircraft and method of transporting a load suspended from the aircraft

Abstract

An aircraft (1) configured to be able to hover is described, comprising a fuselage (2), a support element (13, 55) adapted to support a load (10, 51), made of elastically deformable material and constrained on the fuselage (2), the support element (13, 55) being movable to an operating position in which it is at least partially disposed outside the fuselage (2) and supports the load (10, 51), the aircraft (1) comprising a sheath (20, 60) which surrounds the support element (13, 55) disposed in the operating position, the sheath (20, 60) being configured to limit the elastic return of the support element (13, 55) in the event of breakage of the support element (13, 55) disposed in the operating position.

Description

[0001] Cross-references to related applications

[0002] This patent application claims priority to European Patent Application No. 20176645.8, filed on May 26, 2020, the entire disclosure of which is incorporated herein by reference. Technical Field

[0003] The present invention relates to a hovering aircraft, particularly a helicopter or a thrust-reversing aircraft.

[0004] The present invention also relates to a method for transporting a load suspended on the aircraft. Background Technology

[0005] Hovering aircraft are advantageous for recovering and / or transporting people or goods in emergency situations and / or in hard-to-reach locations, such as recovering shipwrecked persons or unloading materials in inaccessible areas.

[0006] More specifically, according to the first known scheme, the aircraft includes a winch supported by a fixed structure of the aircraft and rescue equipment (such as a carrying strap or stretcher) suspended on a steel cable that moves through the winch.

[0007] More precisely, the aircraft includes openings adapted to allow occupants to enter and exit the fuselage, which are formed on the side of the fuselage itself and engaged by a hatch during normal flight operations.

[0008] To facilitate recovery, the hatch is brought into position through the open passageway. The rescue equipment is first lowered, and then raised along with the personnel and / or items to be recovered.

[0009] At this point, the rescue equipment can be manually or using appropriate tools to pass through the opening back into the aircraft's fuselage.

[0010] During the descent and ascent of the rescue equipment, the free length of the steel cable increases and decreases accordingly.

[0011] According to another known design, the aircraft includes a center-of-gravity hook that is connected to the fuselage via a rope at the center of gravity.

[0012] Center-of-gravity hooks are used to transport loads outside the fuselage, especially for large and / or heavy loads that need to be unloaded in hard-to-reach areas.

[0013] In general, using a center of gravity hook requires a professional to attach the load to the hook while the aircraft is hovering.

[0014] The load is unloaded either electronically or manually by operating it directly on the hook.

[0015] A typical application of the center of gravity hook is to transport water buckets filled with water to be released in a fire area.

[0016] In the use of the center of gravity hook, the length of the rope remains substantially constant.

[0017] In the event of breakage, the steel cable in the first known solution or the rope in the second known solution elastically rebounds straight up, i.e. towards the helicopter.

[0018] Said elastic rebound creates the risk of the steel cable or rope hitting the aircraft, in particular the rotors of the aircraft.

[0019] Said hit obviously threatens the safety of the aircraft itself.

[0020] It is perceived in the art the need to limit the risk of the steel cable or rope hitting the aircraft in the event of breakage.

[0021] More specifically, it is perceived in the art the need to limit the elastic rebound of the steel cable or rope and to change as little as possible the structural characteristics of the steel cable or rope itself, i.e. not to weaken the steel cable or rope itself and not to change its stiffness.

[0022] Furthermore, it is perceived in the art the need to limit said elastic rebound and to maintain as much as possible the possibility of easily checking the steel cable or rope itself.

[0023] It is also perceived in the art the need to limit said elastic rebound without excessively increasing the weight of the aircraft.

[0024] With particular reference to said further known solution provided with a center of gravity hook, it is perceived in the art the need to limit the elastic rebound of the rope and at the same time to enhance the protection against atmospheric agents and to reduce the risk of damage due to the hit against objects with sharp edges.

[0025] US 4,005,852 describes a winch recovery device of a helicopter capable of emitting a warning signal in the event of failure.

[0026] US 1,019,600 and GB 2613646A describe helicopters equipped with a center of gravity hook.

[0027] CN109878732A discloses a sampling unmanned aerial vehicle, which aims to improve the efficiency of sampling and reduce the work intensity of geologists. The sampling unmanned aerial vehicle comprises an unmanned aerial vehicle body, a lifting mechanism and a grabbing mechanism. The lifting mechanism comprises a first electromagnet, a first armature, a first sleeve, a first push-pull member and a first elastic member. One end of the first sleeve is fixed to the unmanned aerial vehicle body, and the other end is provided with a first fixing member. The first electromagnet is arranged in the first sleeve, and the first armature is slidingly nested in the first sleeve. The first armature is arranged opposite to the first electromagnet, one end of the first push-pull member is connected to the first armature, and the other end of the first push-pull member is provided with a sliding part which is movable through the first fixing member. The first elastic member is arranged between the first armature and the first fixing member, and the first armature is configured to be powered at the first electromagnet. The first armature is configured to drive the first push-pull member to move towards the first electromagnet.

[0028] CA2370897A discloses a helicopter wear line cover plate for protecting and separating a load bearing cable for lifting a load suspended from a helicopter from a non-load bearing cable for controlling release of the load, comprising: a pair of elongate flat side member connected to each other in a longitudinal direction along two attachment lines to form a first tube between the side members; a first attachment member attached to one side member near a first edge; and a second attachment member attached to the other side member away from the first edge. When the first and second attachment members are attached to each other, the side members form a second tube parallel to the first tube and separated from the tube by one side member, and the diameters of the first and second tubes are large enough to allow the cable to move freely longitudinally within the first and second tubes when the first and second attachment members are attached to each other. SUMMARY

[0029] The object of the present invention is to provide a hovering-capable aircraft that can meet at least one of the above needs in a simple and economical manner.

[0030] The above objects are achieved by the present application, which relates to an aircraft configured to be able to hover, comprising a fuselage and a support element adapted to support a load, made of elastically deformable material and constrained to said fuselage, said support element being movable to at least one operating position in which it is at least partially disposed outside said fuselage and supports said load, said aircraft further comprising a sheath which surrounds said support element when, in use, said support element is disposed in said operating position, said sheath being configured to limit the elastic return of said support element in the event of breakage of said support element in said operating position, said aircraft comprising a winch, which is operatively connected to said support element, and a box for housing said winch, said winch being operable to move said support element between at least one said operating position, in which said support element projects outside said box and supports said load, and a storage position, in which said support element is inside said box. Said sheath comprises at least a first ring, which is fixed to said box, a second ring, which is fixed to one end of said support element disposed on one side of said load, and at least one flexible element, which is interposed between said first ring and said second ring and has a first length when said support element is in at least one said operating position and a second length, which is smaller than said first length, when said support element is in said storage position.

[0031] Optionally, said aircraft has one or more of the following characteristics:

[0032] Said sheath has a first length in said operating position, which is greater than a second breakage length of said support element in the presence of a load parallel to a first extension axis of said support element in said operating position, said second breakage length being the sum of a nominal length of said support element in the absence of said load and an amount of elastic deformation of said support element due to said load in the event of breakage of said support element;

[0033] Said sheath has a first breakage load, which is smaller than a second breakage load of said support element, said first breakage load being less than one fifth of said second breakage load;

[0034] Said sheath has a preferential breakage portion at one end thereof disposed on one side of said fuselage and opposite said load;

[0035] When said support element is in said storage position, said first ring is disposed inside said box at a first distance from said second ring, when said support element is in said operating position, said first ring and said second ring are disposed outside said box and at a second distance, which is greater than said first distance;

[0036] said flexible element is arranged in an extended configuration, in which it is elongated along said first extension axis and extends outside said box, with said support element in at least one said operating position, or in a folded configuration, in which it is folded on itself transversely to said first extension axis, is partially housed inside said box and has a length smaller than in said extended configuration, and / or said flexible element is crossed by said support element and is configured to allow contact with said support element when arranged in said extended configuration;

[0037] said flexible element is shaped to define at least one pair of eyelets symmetrical with respect to said first extension axis when said support element is in said storage position;

[0038] said aircraft comprises at least one first storage element and at least one second storage element interposed between said first ring and said second ring, said first and second storage elements being axially spaced from each other when said support element is in at least one said operating position and one is housed inside the other when said support element is in said storage position, said flexible element being axially interposed between said first and second storage elements when said support element is in at least one said operating position and radially interposed between said first and second storage elements when said support element is in said storage position;

[0039] said aircraft comprises a first flexible element axially interposed between said first ring and said first storage element when said support element is in at least one said operating position, said first flexible element being radially interposed between said first storage element and said box when said support element is in said storage position;

[0040] said first and second storage elements taper from said second ring towards said first ring, said first storage element being interposed between said first ring and said second storage element, said first and second storage elements each comprising a first surface and a second surface axially facing each other, said first surface having an extension greater than said second surface, said first surface of said first storage element being greater than said first surface of said second storage element, said second surface of said first storage element being greater than said second surface of said second storage element;

[0041] The aircraft comprises a first module formed by a respective said first storage element and a respective said first flexible element; a second module formed by a respective said second storage element and a respective second flexible element, the first module and the second module being axially spaced apart from each other and axially interposed between the first ring and the second ring when the support element is in at least one said operating position, the first module and the second module being axially abutted to each other when the support element is in the storage position;

[0042] The flexible elements are made of fabric or plastic material;

[0043] The aircraft is a helicopter or a convertiplane or a drone.

[0044] According to the present application, there is also provided a method of transporting a load suspended on the above-mentioned aircraft capable of hovering, comprising the steps of: i) connecting a support element to the aircraft and to the load to be transported, the support element being elastically deformable; ii) connecting a sheath to at least the load independently of the support element, the sheath surrounding the support element and being configured to limit the elastic return of the support element in the event of breakage of the support element; and iii) keeping the sheath at least partially slack during breakage of the support element, the method comprising a further step iv) of tensioning the sheath following the step iii) by action of the load until breakage of the sheath.

[0045] Optionally, the method comprises a further step v) of keeping the sheath slack and the support element tensioned during the usual steps of transporting the load.

[0046] According to the application, there is also provided a vehicle configured to be able to hover, comprising: a fuselage; and a support element adapted to support a load, made of elastically deformable material and constrained on said fuselage, said support element being movable to at least one operating position in which it is at least partially disposed outside said fuselage and supports said load, said support element being a cord comprising first ends opposite each other, one of which is connected to a first connector connected to said fuselage and the other of which is connected to a second connector connected to said load, so as to maintain said load at a fixed distance from said fuselage when said cord is disposed in said operating position, said vehicle further comprising a sheath which, in use, surrounds said support element when said support element is disposed in said operating position, said sheath comprising second ends opposite each other, independently of said first ends of said support element, one of which is connected to said first connector and the other of which is connected to said second connector, said sheath being configured, in use, to limit the elastic return of said support element in the event of breakage of said support element in said operating position, said sheath having a first length greater than a second breakage length of said support element in the presence of a load parallel to a first extension axis of said support element in said operating position, so as to maintain said load suspended on said sheath, which in use remains relaxed and intact, when said support element breaks in use, said second breakage length being a maximum breakage length reached by said support element in use under the action of said load, said sheath having a preferential breakage portion at one of its second ends disposed on one side of said fuselage and opposite said load.

[0047] Optionally, said vehicle has one or more of the following characteristics:

[0048] said maximum breakage length being the sum of a nominal length of said support element in the absence of said load and an amount of elastic deformation of said support element in use in the event of breakage of said support element due to said load;

[0049] said sheath having a first breakage load smaller than a second breakage load of said support element, said first breakage load being less than one fifth of said second breakage load;

[0050] said vehicle is a helicopter or a convertiplane or a drone. BRIEF DESCRIPTION OF DRAWINGS

[0051] In order to better understand the present application, a preferred embodiment is described below by way of non-limiting example and with reference to the attached drawings, in which:

[0052] Figure 1 is a perspective view of a vehicle able to hover according to the application, comprising a load lifting / lowering device;

[0053] Figure 2 is an extremely enlarged perspective view of the aircraft of Figure 1 , in which the lifting / lowering device is in the raised position and some parts have been removed for the sake of clarity;

[0054] Figure 3 is an extremely enlarged perspective view of the lifting / lowering device of Figure 1 and 2 in the lowered position;

[0055] Figure 4 shows some details of Figure 3 further enlarged;

[0056] Figure 5 is an extremely enlarged cross-section along the line V-V of Figure 2 ;

[0057] Figure 6 is a perspective view of the aircraft of Figures 1-5 , in which the center of gravity hook is in the first operating position and some parts have been removed for the sake of clarity; and

[0058] Figure 7 shows the center of gravity hook of Figure 6 in the second operating position. DETAILED DESCRIPTION

[0059] With reference to the attached drawings, reference 1 indicates an aircraft capable of hovering, i.e. of flying at constant height and zero speed.

[0060] The aircraft 1 is, in the example shown, a helicopter.

[0061] Alternatively, the aircraft 1 can be a convertiplane or a drone / UAV.

[0062] With reference to Figure 1 , reference 1 indicates, in particular, a helicopter which essentially comprises:

[0063] a fuselage 2;

[0064] a main rotor 3 located at the top of the fuselage 2 and rotatable about a first axis; and

[0065] an anti-torque rotor 4 located at one tail end of the fuselage 2 and rotatable about its own second axis transversal to the first axis.

[0066] More in detail, the fuselage 2 comprises a pair of sides 5a, 5b defining respective openings 6a, 6b for access to the fuselage 2.

[0067] The fuselage 2 also comprises a head 7 and a tail 8.

[0068] A longitudinal axis X of the helicopter 1 from the head 7 to the tail 8 can be identified.

[0069] A further axis Z orthogonal to the axis X and arranged vertically can also be identified when the helicopter 1 is on the ground or in the normal flight configuration.

[0070] The helicopter 1 also comprises a transport device 9 for transporting a load 10, for example a recovery basket or a harness or a stretcher.

[0071] In Figures 1-5 In the example shown, the transport device 9 is adapted to allow the load 10 to be raised into the fuselage 2 or lowered towards the ground.

[0072] In more detail, the transport device 9 comprises:

[0073] a box 11 which projects in a cantilevered manner from the sides 5a, 5b outside the fuselage 2;

[0074] a winch 12 housed inside the box 11; and

[0075] a cable 13 wound on the winch 12 and sliding in the vertical direction and provided with a hook 14 for supporting the load 10.

[0076] The box 11 comprises:

[0077] a cylindrical portion 16 having an axis parallel to the axis X of the helicopter 1; and

[0078] a cylindrical portion 17 which projects in a cantilevered manner from the portion 16 parallel to the axis Z and is open below.

[0079] In particular, the portion 17 is open below and symmetrical with respect to the axis Z to allow the cable 13 to be unwound / wound.

[0080] The cable 13 extends along an axis A.

[0081] The cable 13 is also movable in sliding along the vertical direction between:

[0082] a storage position (in which it is completely wound on the winch 12 inside the portion 17 of the box 11 and the hook 14 is directed towards the opening 16); and Figure 2 a plurality of working positions (one of which is shown in

[0083] ), in each of which it at least partially projects outside the box 11 to have a respective free length along the axis Z arranged vertically in use. Figure 3

[0084] ​It should be noted that in the following description, expressions such as "above", "below", "upwards", "downwards" and the like refer to one of the working positions of the cable 13 with the axis A parallel to the axis Z.

[0085] The hook 14 is provided at an end 15 of the cable 13 opposite the winch 12.

[0086] In each working position, the end 15 is at a respective first height. In the storage position, the end 15 is at a second height higher than the first height.

[0087] In other words, the cable 13 lowers with respect to the fuselage 2 as it moves from the storage position towards each working position and raises with respect to the fuselage 2 as it moves from each working position towards the storage position.

[0088] In more detail, the cable 13 is provided in the storage position when the load 10 is hoisted on the fuselage 2 or when the load 10 is provided outside the fuselage 2 for being lowered.

[0089] On the contrary, the cable 13 is provided in the respective working position when the load 10 provided on the ground is connected to the hook 14.

[0090] The cable 13 also comprises a cylindrical element 18 provided near the hook 14.

[0091] The cable 13 is made of elastically deformable material.

[0092] In the example shown, the cable 13 is a steel cable.

[0093] In the event of breakage of the cable 13 provided in one of the lowered operating positions, the portion of the cable 13 connected to the winch 12 elastically returns upwards and towards the fuselage 2 of the helicopter 1.

[0094] The helicopter 1 comprises a sheath 20 which, in use, surrounds the cable 13 when the latter is provided in one of the working positions; the sheath 20 is configured to limit the elastic return of the cable 13 in the event of breakage of the cable 13 provided in one of the working positions.

[0095] In this way, the sheath 20 prevents the cable 13 from hitting and possibly damaging the fuselage 2 and the rotors 3, 4 of the helicopter 1 during its elastic return upwards.

[0096] In more detail, the sheath 20 extends along an axis B parallel to the axis Z and can move between:

[0097] a fully extended position (A), in which it projects outside the box 11; and Figure 3 a fully retracted storage position (B).

[0098] In the fully extended position (A), the sheath 20 is configured to elastically deform in the event of breakage of the cable 13 provided in one of the working positions.Figure 5 ), wherein it has a smaller length than the extended position and is partially housed inside the box 11.

[0099] The sheath 20 is arranged in the fully extended position when the cable 13 is in the working position corresponding to the maximum free length outside the box 11.

[0100] Conversely, the sheath 20 is arranged in the contracted position when the cable 13 is in the storage position.

[0101] In this way, after the rupture of the cable 13 arranged in one of the operating positions, the elastic return of the sheath 20 is less than the elastic return of the cable 13. Therefore, the cable 13 remains housed in the sheath 20.

[0102] Preferably, when the cable 13 is in one of the operating positions, the free length of the cable 13 outside the box 11 is less than the free length of the sheath 20.

[0103] In this way, in whichever operating position, the length of the sheath 20 is greater than the maximum rupture length of the cable 13 in the event of a situation leading to the rupture of the cable. By way of non-limiting example, the maximum rupture length of the cable 13 is indicated as the sum of the nominal length of the cable 13 without the load 10 and the amount of elastic deformation due to the load 10 in the event of rupture of the cable 13 itself.

[0104] In this way, when the cable 13 ruptures, the sheath 20 remains substantially intact and in place. This allows the cable 13 to be kept during the elastic rebound.

[0105] After a few minutes from the rupture, the cable 13 stops the elastic rebound. The cable 13 remains inside the sheath 20, with the load 10 still attached thereto.

[0106] Subsequently, the load 10 lengthens the sheath 20 to its maximum length, until it ruptures.

[0107] With reference to Figures 2-5 , the sheath 20 has a tubular shape along the axis B.

[0108] The sheath 20 substantially comprises:

[0109] a plurality of rings 21, 22, 23, 24; and

[0110] a plurality of flexible elements 25a, 25b, each interposed between a pair of rings 21, 22, 23, 24 consecutive to each other along the axis B.

[0111] In the example shown, the rings 21, 22, 23, 24 lie on respective planes parallel to each other and orthogonal to the axis B.

[0112] As will be described in greater detail below, each flexible element 25a, 25b is arranged:

[0113] a fully extended position in which it is elongated along the axis B when the sheath 20 is arranged in a fully extended position; Figure 5 ) ; or

[0114] a storage position in which it is folded on itself symmetrically with respect to the axis B when the sheath 20 is arranged in a retracted position.

[0115] The rings 21, 22, 23, 24 are preferably made of a self-lubricating material, so as to reduce wear in the event of any contact between the rings 21, 22, 23, 24 and the cable 13.

[0116] The sheath 20 further comprises a plurality of storage elements 30a, 31a, 32a; 30b, 31b, 32b carried by the respective rings 23, 24.

[0117] The storage elements 30a, 31a, 32a; 30b, 31b, 32b extend above the respective rings 23, 24 and inside the respective flexible elements 25a, 25b arranged above them.

[0118] The storage elements 30a, 31a, 32a; 30b, 31b, 32b are spaced apart from each other along the axis B and are interposed between respective pairs of rings 23, 24 consecutive to each other.

[0119] In the example shown, the number of storage elements 30a, 31a, 32a is three and the number of storage elements 30b, 31b, 32b is also three.

[0120] The storage elements 30a, 31a, 32a; 30b, 31b, 32b are shaped as truncated cones coaxial to the axis B and crossed by the cable 13.

[0121] The storage elements 30a, 31a, 32a; 30b, 31b, 32b taper from the hook 14 towards the box 11, i.e. upwards from the bottom.

[0122] More specifically, each storage element 30a, 31a, 32a; 30b, 31b, 32b comprises: Figure 4 ) :

[0123] a head surface 35 connected to the respective ring 23, 24;

[0124] a head surface 36 shaped as a circular crown having a smaller diameter than the surface 35 and axially opposite to the surface 35; and

[0125] a lateral truncated-cone surface 37 extending axially between the surfaces 35, 36.

[0126] Each storage element 30a, 31a, 32a; 30b, 31b, 32b is tapered in particular from the respective surface 35 towards the respective surface 36.

[0127] More particularly, the surfaces 35, 36 are shaped as circular crowns through which the cable 13 passes.

[0128] The diameter of the surfaces 35, 36 of the storage elements 30a, 30b is greater than the diameter of the surfaces 35, 36 of the storage elements 31a, 31b.

[0129] The diameter of the surfaces 35, 36 of the storage elements 31a, 31b is greater than the diameter of the surfaces 35, 36 of the storage elements 32a, 32b.

[0130] The distance between the surfaces 35, 36 of the storage elements 30a (30b) along the axis B is greater than the distance between the surfaces 35, 36 of the storage elements 31a (31b) along the axis B.

[0131] The distance between the surfaces 35, 36 of the storage elements 31a (31b) along the axis B is greater than the distance between the surfaces 35, 36 of the storage elements 32a (32b) along the axis B.

[0132] The sheath 20 further comprises Figure 4 and 5 :

[0133] a module 40 formed by the rings 21, 23, the respective flexible element 25a and the respective storage elements 30a, 31a, 32a; and

[0134] a module 41 formed by the rings 24, 22, the respective flexible element 25b and the respective storage elements 30b, 31b, 32b.

[0135] The transition of the sheath 20 from the fully extended position to the retracted position causes the arms 27 of the flexible elements 25a, 25b to contract axially and the rings 21, 22, 23, 24 contiguous to each other to approach axially. Conversely, the storage elements 30a, 31a, 32a; 30b, 31b, 32b substantially maintain the same frustoconical shape during said transition.

[0136] With reference to Figure 3 the fully extended position of the sheath 20 shown, the rings 21, 22, 23, 24 are spaced apart from each other along the axis Z.

[0137] The flexible elements 25a, 25b are elongated parallel to the axis Z and each interposed between a respective pair of rings 21, 22, 23, 24 contiguous to each other.

[0138] The rings 21, 22 define respective axial ends of the sheath 20 opposite to each other.

[0139] More precisely, the first flexible element 25a arranged above intervenes between the portion 17 of the box 11 and the ring 21.

[0140] The second flexible element 25a is arranged immediately below the above-mentioned first flexible element 25a arranged above and intervenes between the ring 21 and the ring 23 arranged below.

[0141] The intermediate flexible element 25a intervenes between the rings 23.

[0142] The flexible element 25a arranged below intervenes between the ring 23 arranged below and the ring 24 arranged above.

[0143] The flexible element 25b arranged above intervenes between the respective rings 24.

[0144] The flexible element 25b arranged below intervenes between the ring 24 arranged below and the ring 22.

[0145] Each flexible element 25a, 25b defines, in the fully extended position:

[0146] a pair of bases 26, which are opposite each other and are fixed to the respective rings 21, 22, 23, 24; and

[0147] a plurality of (four in the example shown) arms 27, which are equiangularly spaced with respect to each other and extend between the respective bases 26 with respect to the cable 13, allowing the operator of the winch 12 to see and / or hold in his hand the cable 13 sliding within the element 25a during the operations on the winch 12 itself.

[0148] The arms 27 are symmetrical and parallel to the axis B and first diverge and then converge from the ring 21 towards the ring 22.

[0149] The arms 27 of each flexible element 25a, 25b protrude radially with respect to the axis B with respect to the respective rings 21, 22, 23, 24.

[0150] The arms 27 define, at the intermediate plane of the flexible elements 25a, 25b equidistant from the respective bases 26, the maximum dimension of the respective flexible elements 25a, 25b radially with respect to the axis B. The storage devices 30a, 31a, 32a; 30b, 31b, 32b are arranged in succession parallel to the axis B from the ring 21 towards the ring 22.

[0151] The maximum dimension of the flexible element 25a radially with respect to the axis B, which intervenes between the ring 21 and the storage device 30a, is less than the diameter of the portion 17 of the box 11 and greater than the area of the surface 35 of the storage element 30a.

[0152] The maximum dimension of the flexible element 25a (25b) in the radial direction of the axis B between the storage devices 30a, 31a (31a, 32a; 32a, 30b; 30b, 31b; 31b, 32b) is smaller than the area of the surface 35 of the storage element 30a (31a; 32a; 30b; 31b) and greater than the area of the surface 35 of the storage element 31a (32a; 30b; 31b; 32b).

[0153] The maximum dimension of the flexible element 25b in the radial direction of the axis B between the storage device 32b and the ring 22 is smaller than the area of the surface 35 of the storage element 32b.

[0154] With reference to Figure 5 The modules 40, 41 are axially superimposed on each other in the retracted position of the sheath 20.

[0155] The storage device 32a (32b) is radially arranged inside the storage device 31a (31b).

[0156] The storage device 31a (31b) is radially arranged inside the storage device 30a (30b).

[0157] The storage device 30a is partly housed inside the portion 17 of the box 11.

[0158] The surfaces 35, 36 of the storage elements 30a, 31a, 32a; 30b, 31b, 32b are in contact with each other in the axial direction.

[0159] The ring 23 (24) and the flexible element 25a (25b) axially interposed between the storage elements 31a, 32a (30a, 31a; 31b, 32b; 30b, 31b) in the extended position of the sheath 20 are radially interposed between the same storage elements 31a, 32a (30a, 31a; 31b, 32b; 30b, 31b) in the retracted position of the same sheath 20.

[0160] The ring 23 and the flexible element 25a axially interposed between the ring 21 and the storage element 30a in the extended position of the sheath 20 are radially interposed between the storage element 30a and the portion 17 of the box 11 in the retracted position of the same sheath 20.

[0161] The ring 24 and the flexible element 25b axially interposed between the storage element 32b and the ring 22 in the extended position of the sheath 20 are radially arranged outside the storage device 32b in the retracted position of the sheath 20.

[0162] The arms 27 of the flexible elements 25a, 25b are also folded on themselves so as to form respective pairs of eyelets 39 in a longitudinal section having a plane parallel to the axes X, Z.

[0163] With particular reference to Figure 5 , the eyelets 39 are in axial contact with each other parallel to the axis Z and extend between a respective pair of rings 21, 22, 23, 24 continuous with each other.

[0164] More particularly, each eyelet 39 comprises a pair of portions 43, 44 extending downwards and gradually increasing in distance from each other starting from the respective ring 23, 24.

[0165] In the example shown, the sheath 20 is made of fabric or extruded plastic material.

[0166] In the first embodiment, the breaking load of the sheath 20 is preferably less than the breaking load of the cable 13.

[0167] More preferably, the breaking load of the sheath 20 is less than one fifth of the breaking load of the cable 13.

[0168] In the second embodiment, the dimensions of the sheath 20 are preferably set to break at the ring 21.

[0169] To this end, the sheath 20 comprises at the ring 21 a sacrificial element (not shown) configured to break at a breaking load value less than the breaking load value of the remaining part of the sheath 20.

[0170] With reference to Figure 6 and 7 , the helicopter 1 also comprises further means 50 adapted to allow the transport of a further load 51.

[0171] More precisely, the means 50 are configured to keep the load 51 at a constant distance from the fuselage 2, not allowing it to be raised / lowered with respect to the fuselage 2.

[0172] The means 50 are called "long line assembly" and essentially comprise ( Figure 6 ):

[0173] a connector 53 shaped like a hook, which hangs on the lower part 52 of the fuselage 2 and is called in the art "gravity hook";

[0174] a connector 54 shaped like a hook and connected to the load 51; and

[0175] a rope 55 having opposite ends 56, 57 connected to the connectors 53, 54.

[0176] In Figure 6 the normal operating condition shown, the rope 55 is tensioned by the load 51 and extends along its own vertical and parallel to the axis Z axis C.

[0177] In the event of rupture of the cord 55 in the normal operating position, the cord 55, connected to the fuselage 2, elastically returns upwards and towards the fuselage 2 of the helicopter 1.

[0178] The helicopter 1 comprises a further sheath 60 which surrounds the cord 55 and is configured to limit the elastic return of the cord 55 from the normal operating condition in the event of rupture of the cord 55 itself.

[0179] In this way, the sheath 60 prevents the cord 55 from hitting and possibly damaging the fuselage 2 and the rotors 3, 4 of the helicopter 1 during its elastic return.

[0180] The diameter of the sheath 60 is greater than that of the cord 55, thus allowing the cord 55 itself to move freely within the sheath 60 during the elastic return phase.

[0181] The sheath 60 comprises respective end portions 61, 62 which are fixed to the connectors 53, 54 and are movable independently of the cord 55.

[0182] The length of the sheath 60 is greater than the maximum rupture length of the cord 55, i.e. the maximum length reached by the cord 55 under the action of the load 51.

[0183] The sheath 60 is slack when the cord 55 is tensioned by the load 51.

[0184] In this way, similarly to what is described for the sheath 20, when the cord 55 ruptures, the load 51 remains suspended on the sheath 60 which is still slack and intact.

[0185] The sheath 60 thus retains the cord 55 during the elastic rebound.

[0186] After a few minutes from the rupture, the cord 55 stops the elastic rebound without damaging the helicopter 1.

[0187] In the meantime, the sheath 60 is tensioned under the weight of the load 51 still attached thereto until it ruptures, allowing the load 51 to fall.

[0188] In a first embodiment, the rupture load of the sheath 60 is less than the rupture load of the cord 55.

[0189] More preferably, the rupture load of the sheath 60 is less than one fifth of the rupture load of the cord 55.

[0190] In a second embodiment, the sheath 60 is preferably sized to rupture at the end portion 61 thereof.

[0191] To this end, the sheath 60 comprises, at the end portion 61, a sacrificial element (not shown) configured to rupture at a rupture load value less than that of the remaining portion of the sheath 60.

[0192] The operation of the helicopter 1 will be described starting from the condition in which the cable 13 is arranged in the storage position. In said storage position, the cable 13 is wound on the winch 12 inside the box 11.

[0193] In this condition, the sheath 20 is in the retracted position. Figure 5

[0194] In more detail, the modules 40, 41 overlap each other in the axial direction.

[0195] The storage device 32a (32b) is arranged radially inside with respect to the storage device 31a (31b).

[0196] The storage device 31a (31b) is arranged radially inside with respect to the storage device 30a (30b).

[0197] The storage device 30a is partly housed inside the portion 17 of the box 11.

[0198] The surfaces 35, 36 of the storage elements 30a, 31a, 32a; 30b, 31b, 32b are in contact with each other in the axial direction.

[0199] The first ring 23 (24) and the first flexible element 25a (25b) are radially interposed between the storage elements 31a, 32a (30a, 31a; 31b, 32b; 30b, 31b) in the retracted position of the same sheath 20.

[0200] The further ring 23 and the further flexible element 25a are radially interposed between the storage element 30a and the portion 17 of the box 11.

[0201] The second ring 24 and the second flexible element 25b are arranged radially outside the storage device 32b in the retracted position of the sheath 20.

[0202] The arms 27 of the storage elements 30a, 30b are folded on themselves to form the respective pairs of eyelets 39.

[0203] From this condition, the winch 12 is operated to lower the cable 13 along the vertical direction.

[0204] During said movement, the cable 13 exits the box 11.

[0205] Once the cable 13 is lowered to the desired height, it is in one of the operating positions.

[0206] In said operating position, the load 10 is suspended on the hook 14.

[0207] When the cable 13 is arranged in the fully lowered operating position, the sheath 20 is in the fully extended position (). Figure 3 .​

[0208] Transition from the retracted position to the fully extended position causes the arms 27 to extend. Thus, in the fully extended position of the sheath 20, the rings 21, 22, 23, 24 are spaced apart from each other along the axis Z.

[0209] The flexible elements 25a, 25b are each interposed between a pair of rings 21, 22, 23, 24 consecutive to each other.

[0210] The rings 21, 22 define respective axial ends of the sheath 20 opposite each other.

[0211] From the ring 21 towards the ring 22, parallel to the axis Z, the storage devices 30a, 31a, 32a; 30b, 31b, 32b are arranged in succession and axially spaced apart along the axis Z.

[0212] In the event of rupture of the cable 13 in the lowered operating position, the portion of the cable 13 connected to the winch 12 elastically returns upwards.

[0213] The sheath 20, due to its greater length than the cable 13, remains in place for a time sufficient to limit the elastic return of the cable 13.

[0214] The sheath 20 thus prevents the cable 13 from impacting and possibly damaging the fuselage 2 and the rotors 3, 4 of the helicopter 1 during its elastic return.

[0215] In the first embodiment, once the elastic energy of the cable 13 has completely dissipated, the load 10 remains suspended on the sheath 20 until the latter breaks in the presence of a stress significantly less than that required for the rupture of the cable 13 (for example, a tensile stress having a value equal to one fifth of that required for the rupture of the cable 13).

[0216] In this way, the elastic return of the sheath 20 is particularly reduced upwards and does not pose a risk of impact on the rotors 3, 4.

[0217] In the second embodiment, the sheath 20 preferably breaks at the ring 21.

[0218] In this way, the elastic return of the sheath 20 is directed downwards and does not pose a risk of impact on the rotors 3, 4.

[0219] The cord 55 serves to transport the load 51 at a constant distance from the fuselage 2, i.e. without raising or lowering the load 51 with respect to the fuselage 2.

[0220] More specifically, the load 51 is hung on the connector 54 and released while the helicopter 1 is still flying.

[0221] In the following from Figure 6The illustrated condition describes the operation of the helicopter 1 in which the rope 55 is pulled tight by the load 51 and extends along its own vertically disposed axis C.

[0222] The sheath 60 encircles the rope 55 during the transport of the load 51.

[0223] During said transport step of the load 51, the sheath 60 does not extend completely, but is partially slack.

[0224] In the case of an overload, for example due to the load 51 getting entangled, the rope 55 is pulled further until it reaches its maximum length. In said condition, the sheath 60 remains partially slack.

[0225] The rope 55 reaches its maximum breaking length until it breaks. When the rope 55 breaks, the sheath 60 is still slack.

[0226] This is because the length of the sheath 60 is less than the maximum length of the rope 55.

[0227] At the moment after the breaking of the rope 55, the elasticity of the rope 55 stops for a short time, the load 51 falls and the sheath 60 lengthens until it is completely pulled tight.

[0228] At this point, the sheath 60 is completely pulled tight and causes the load 51 to fall, producing a limited elastic return that does not damage the helicopter 1.

[0229] During the breaking phase of the rope 55, the sheath 60 limits the elastic return of the rope 55.

[0230] More in detail, the sheath 60, due to its greater length than the rope 55, remains in place for a time sufficient to limit the elastic return of the rope 55 itself, thus preventing the latter from hitting and possibly damaging the fuselage 2 and the rotors 3, 4 of the helicopter 1 during its elastic return.

[0231] In the first embodiment, once the elasticity of the rope 55 has completely dissipated, the load 51 remains suspended on the sheath 60 until the latter breaks in the presence of a stress that is significantly less than that required for the breaking of the rope 55 itself.

[0232] In this way, the upward elastic return of the rope 55 is particularly reduced and does not pose a risk of impact on the rotors 3, 4.

[0233] In the second embodiment, the sheath 60 breaks, preferably at the end 61.

[0234] In this way, the elastic return of the sheath 60 is directed downwards and does not pose a risk of impact on the rotors 3, 4.

[0235] The inspection of the features of the helicopter 1 according to the present application allows the advantages obtained to be evident.

[0236] More in detail, the sheaths 20, 60 encircle the respective cable 13 / rope 55 arranged in the operating position.

[0237] In this way, in the event of breakage of the cable 13, the sheaths 20, 60 limit the elastic return of the cable 13 and of the rope 55, respectively.

[0238] Therefore, it is possible to avoid or substantially reduce the risk that such elastic return will damage the rotors 3, 4, jeopardizing the safety of the helicopter 1.

[0239] The length of the sheaths 20, 60 is greater than that of the cable 13 and of the rope 55, respectively, when they are in the operating position.

[0240] This allows ensuring that the cable 13 and the rope 55 are limited within the respective sheaths 20, 60 during the elastic return phase.

[0241] In particular, in the first embodiment described above, the load 10, 51 remains suspended on the respective sheath 20, 60 until the latter breaks in the presence of a stress significantly less than that required for breakage of the cable 13 and of the rope 55.

[0242] In this way, when breaking, the sheaths 20, 60 develop a smaller elastic energy than the respective cable 13 and rope 55.

[0243] This results in an elastic return of the sheaths 20, 60 substantially less than the respective elastic return of the cable 13 and of the rope 55.

[0244] Therefore, the risk of impact of the sheaths 20, 60 against the rotors 3, 4 of the helicopter 1 is reduced.

[0245] In the second embodiment, the sheaths 20, 60 are preferably sized to break at the loop 21 and at the end 61, respectively.

[0246] Therefore, the elastic return of the sheaths 20, 60 is directed towards the end 62, i.e. towards the opposite side of the rotors 3, 4. Therefore, it is possible to use breakage loads of the sheaths 20, 60 comparable to the breakage loads of the cable 13 and of the rope 55.

[0247] In this way, on the one hand, the sheaths 20, 60 allow limiting the elastic return of the cable 13 and of the rope 55, respectively. On the other hand, the reduced upward elastic return or downward return of the sheaths 20, 60 does not create a substantial risk of impact against the rotors 3, 4 of the helicopter 1.

[0248] The flexible elements 25a, 25b of the sheath 20 have a smaller length when the cable 13 is in the stowed position and a greater length when the cable 13 is in the operating position.

[0249] In this way, during lowering / rising of the cable 13, the sheath 20 has a reduced length when the cable 13 is in the stowed position and can therefore be accompanied by a reduction in the free length of the cable 13 outside the box 11.

[0250] The stowing elements 30a, 30b; 31a, 31b; 32a, 32b perform the centering function of the flexible elements 25a, 25b when the sheath 20 moves from the extended position to the retracted position. In this way, when the sheath 20 moves from the extended position to the retracted position, the stowing elements 30a, 30b; 31a, 31b; 32a, 32b make correct folding of the flexible elements 25a, 25b particularly reliable and repeatable.

[0251] The self-lubricating material of the rings 21, 22, 23, 24 allows to reduce wear in the event of any contact between the rings 21, 22, 23, 24 and the cable 13.

[0252] The sheath 60 and the cord 55 are connected to the connectors 53, 54 independently of each other.

[0253] Thereby, the sheath 60 can effectively limit the elastic return of the cord 55 itself in the event of accidental breakage of the cord 55, to keep the load 51 at a constant distance from the fuselage 2.

[0254] The sheath 60 also allows to protect the cord 55 from atmospheric agents and to prevent it from impacting sharp and pointed objects.

[0255] The sheaths 20, 60 are made of particularly light materials that do not increase the overall weight of the helicopter 1. For example, the sheaths 20, 60 can be made by extruded plastic (thus non-woven) material or braiding.

[0256] The sheaths 20, 60 are formed with a reversible lateral opening system so that they can be easily and quickly mounted around the cable 13 or the cord 55. For example, the lateral opening system can comprise portions of Velcro or zip.

[0257] The sheaths 20, 60 also allow to easily check the cable 13 and the cord 55, respectively.

[0258] In addition, the sheaths 20, 60 do not alter the mechanical characteristics of the cable 13 and the cord 55, respectively, in particular the stiffness and strength of the cable 13 and the cord 55 themselves.

[0259] Finally, it is clear that modifications and variants can be made to the aforementioned aircraft 1 without thereby departing from the scope of protection of the present invention.

[0260] The helicopter 1 can in particular be a change of thrust aircraft.

Claims

1. An aircraft (1) configured to hover, comprising: Fuselage (2); as well as A support element (13), adapted to support a load (10), is made of an elastically deformable material and is constrained to the fuselage (2). The support element (13) is movable to at least one operating position in which it is at least partially located outside the body (2) and supports the load (10). The aircraft (1) also includes a sheath (20) surrounding the support element (13) when it is positioned in the operating position during use. The sheath (20) is configured to restrict the elastic return of the support element (13) in the event of breakage of the support element (13) in at least one of the operating positions during use. The aircraft (1) is characterized in that it comprises: A winch (12) is operatively connected to the support element (13); A housing (11) for accommodating the winch (12), The winch (12) is operable to move the support element (13) between the following positions: At least one of the operating positions, wherein the support element (13) extends outside the housing (11) and supports the load (10); and Storage location, wherein the support element (13) is located inside the housing (11), The sheath (20) includes at least: The first ring (21) is fixed to the housing (11); The second ring (22) is fixed to one end of the support element (13) located on the side of the load (10); and At least one flexible element (25a, 25b) is located between the first ring (21) and the second ring (22), and has a first length when the support element (13) is in at least one of the operating positions and a second length smaller than the first length when the support element (13) is in the storage position.

2. The aircraft according to claim 1, characterized in that, The sheath (20) has a first length in the operating position, which is greater than the second fracture length of the support element (13) when a load is present parallel to the first extension axis (B) of the support element (13) in the operating position. The second fracture length is the sum of the nominal length of the support element (13) when there is no load (10) and the amount of elastic deformation caused by the load (10) when the support element (13) breaks.

3. The aircraft according to claim 1, characterized in that, The sheath (20) has a first fracture load that is smaller than the second fracture load of the support element (13), and the first fracture load is less than one-fifth of the second fracture load.

4. The aircraft according to claim 1, characterized in that, The sheath (20) has a preferentially fractured portion at one end located on one side of the body (2) and opposite to the load (10).

5. The aircraft according to claim 1, characterized in that, When the support element (13) is in the storage position, the first ring (21) is positioned within the housing (11) at a first distance from the second ring (22). When the support element (13) is in the operating position, the first ring (21) and the second ring (22) are located outside the housing (11) and are separated by a second distance greater than the first distance.

6. The aircraft according to claim 2, characterized in that, The flexible elements (25a, 25b) are disposed in: Its extended structure extends along the first extension axis (B) and extends to the outside of the housing (11), wherein the support element (13) is in at least one of the operating positions; or Its folded structure, which is transverse to the first extension axis (B), folds over itself, is partially contained within the housing (11), and has a length smaller than that in the extended structure, and / or The flexible elements (25a, 25b) are passed through the support element (13) and are configured to allow contact with the support element (13) when the extended configuration is provided.

7. The aircraft according to claim 6, characterized in that, The flexible elements (25a, 25b) are shaped to define at least a pair of eyelets (39) symmetrical with respect to the first extension axis (B) when the support element (13) is in the storage position.

8. The aircraft according to claim 6, characterized in that, It includes at least one first storage element (30a, 31a, 32a) and at least one second storage element (30b, 31b, 32b) located between the first ring (21) and the second ring (22). The first storage element (30a, 31a, 32a) and the second storage element (30b, 31b, 32b) are axially spaced apart from each other when the support element (13) is in at least one of the operating positions, and one is housed within the other when the support element (13) is in the storage position. The flexible elements (25a, 25b) are axially located between the first storage elements (30a, 31a, 32a) and the second storage elements (30b, 31b, 32b) when the support element (13) is in at least one of the operating positions, and are radially located between the first storage elements (30a, 31a, 32a) and the second storage elements (30b, 31b, 32b) when the support element (13) is in the storage position.

9. The aircraft according to claim 8, characterized in that, It includes a first flexible element (25a) that is axially positioned between the first ring (21) and the first storage element (30a) when the support element (13) is in at least one of the operating positions. The first flexible element (25a) is radially positioned between the first storage element (30a) and the housing (11) when the support element (13) is in the storage position.

10. The aircraft according to claim 8, characterized in that, The first storage element (30a, 31a, 32a) and the second storage element (30b, 31b, 32b) taper from the second ring (22) toward the first ring (21). The first storage element (30a, 31a, 32a) is located between the first ring (21) and the second storage element (30b, 31b, 32b). The first storage element (30a, 31a, 32a) and the second storage element (30b, 31b, 32b) each include a first surface (35) and a second surface (36) with their axial ends facing each other. The first surface (35) extends more than the second surface (36). The first surface (35) of the first storage element is larger than the first surface (35) of the second storage element. The second surface (36) of the first storage element is larger than the second surface of the second storage element.

11. The aircraft according to claim 9, characterized in that, It includes: A first module (40) is formed by the corresponding first storage elements (30a, 31a, 32a) and the corresponding first flexible element (25a); The second module (41) is formed by the corresponding second storage elements (30b, 31b, 32b) and the corresponding second flexible element (25b). The first module (40) and the second module (41) are axially spaced apart from each other and axially positioned between the first ring (21) and the second ring (22) when the support element (13) is in at least one of the operating positions. The first module (40) and the second module (41) abut against each other axially when the support element (13) is in the storage position.

12. The aircraft according to claim 4, characterized in that, The flexible elements (25a, 25b) are made of fabric or plastic material.

13. The aircraft according to claim 1, characterized in that, It is a helicopter, a thrust-reversing aircraft, or a drone.

14. A method for transporting a load (10) suspended on a hovering aircraft (1) according to claim 1, comprising the steps of: i) Connecting a support element (13) to the aircraft (1) and the load (10) to be transported, wherein the support element (13) is elastically deformable; ii) A sheath (20) is connected to the load at least independently of the support element (13), the sheath (20) surrounding the support element (13) and configured to limit the elastic return of the support element (13) in the event of breakage; and iii) To maintain at least partial slack in the sheath (20) during the fracture of the support element. The method is characterized by the following additional step iv): following step iii), the sheath (20) is tightened by the action of the load (10) until the sheath (20) breaks.

15. The method according to claim 14, characterized in that, It includes an additional step v): keeping the sheath (20) slack and keeping the support element (13) taut during the regular steps of transporting the load (10).

16. An aircraft (1) configured to hover, comprising: Fuselage (2); as well as A support element (55), adapted to support a load (51), is made of an elastically deformable material and is constrained to the fuselage (2). The support element (55) is movable to at least one operating position where it is at least partially located outside the body (2) and supports the load (51). The support element (55) is a rope (55) comprising first ends (56, 57) opposite to each other, one first end (56) being connected to a first connector (53) connected to the body (2) and the other first end (57) being connected to a second connector (54) connected to the load (51), thereby maintaining the load (51) at a fixed distance from the body (2) when the rope (55) is positioned in the operating position. The aircraft (1) also includes a sheath (60) surrounding the support element (55) when the support element (55) is positioned in the operating position during use. The sleeve (60) is characterized in that it includes second ends (61, 62) opposite to each other, independent of the corresponding first ends (56, 57) of the support element (55), one of the second ends (61) being connected to the first connector (53) and the other second end (62) being connected to the second connector (54). The sheath (60) is configured to restrict the elastic return of the support element (55) in the event of a breakage of the support element (55) located in at least one of the operating positions during use. The sheath (60) has a first length greater than the second fracture length of the support element (55) when a load is present parallel to the first extension axis (C) of the support element (55) in the operating position, thereby keeping the load (51) suspended on the sheath (60) which remains slack and intact during use in the event that the support element (55) breaks during use. The second fracture length is the maximum fracture length reached by the support element (55) under the action of the load (51) during use. The sheath (60) has a preferentially fractured portion at a second end (61) located on one side of the body (2) and opposite the load (51).

17. The aircraft according to claim 16, characterized in that, The maximum fracture length is the sum of the nominal length of the support element (55) when there is no load (51) and the amount of elastic deformation caused by the load (51) during use when the support element (55) breaks.

18. The aircraft according to claim 16, characterized in that, The sheath (60) has a first fracture load that is smaller than the second fracture load of the support element (55), and the first fracture load is less than one-fifth of the second fracture load.

19. The aircraft according to claim 16, characterized in that, It is a helicopter, a thrust-reversing aircraft, or a drone.

Images