RU2300484C1 - Device for transportation of cargo by helicopter - Google Patents

Abstract

FIELD: aeronautical engineering; devices for transportation of cargo in helicopter external store.

SUBSTANCE: proposed device includes container inform of parallelepiped with two tail stabilizers and set of lines of external store connected with helicopter lock. Used as stabilizers are two swivel flaps secured on rear end face of container by means of lag hinges mounted on side surfaces of container. Swivel flaps may be either secured in plane of rear end face during storage or may be turned and secured in open position at angle of 120 to 180° to side walls of container before flight. Swivel flaps are sectional in construction and are provided with additional plates attached by means of lag hinges or without them. Additional plates make it possible to perform more fine adjustment of air incoming flow for longitudinal stability of container in flight. Swivel flaps are fixed in open position by means of rods which are adjustable in length. Lines of helicopter external store have different length: lines secured near rear end face are longer as compared with those secured at front end face, thus ensuring inclination of container longitudinal axis to level at angle of 10 to 35° at hovering.

EFFECT: improved flight characteristics of helicopter.

4 cl, 4 dwg

Description

The invention relates to aircraft, in particular to devices for transporting goods on a cable external suspension of helicopters, and can be used to reduce the cost of flight time in the safe execution of operations for the delivery of goods.

A device for transporting goods is known, which is a box in the form of a parallelepiped with internal rotary flaps, providing re-planning of the container by creating the necessary size sections for the transport of various goods (ed. Certificate of the USSR No. 1364559, class B65D 90/00, 1985) . A disadvantage of the known device, as well as of all poorly streamlined cargo such as a box, is the low speed of transportation on the external suspension of the helicopter, since the internal configuration changes of the container with the help of rotary flaps did not affect its aerodynamic properties.

A device for transporting goods by helicopter, containing a container in the form of a parallelepiped, equipped with nodes for hooking, and a set of slings of external suspension, connected to the lock of the helicopter (RF patent No. 2213678, CL 64D 9/00, 2001). In this device, the container is made of several sections located on a common frame at a distance from each other. Due to changes in the internal configuration, through channels passable for air were created, which improved the aerodynamics of the container and can provide an increase in the speed of transportation of goods.

A disadvantage of the known device is the need to manufacture a sufficiently rigid (and therefore material-intensive) common bed and strong disconnected sections capable of withstanding the large aerodynamic forces arising at high flight speeds. The complexity and high material consumption of the structure can reduce the useful load capacity of the device.

The closest in technical essence, i.e. the prototype is a device for transporting goods by helicopter, containing a parallelepiped-shaped container equipped with two tail stabilizers on the outside and equipped with hooking units, and a set of external slings connected to the helicopter lock (Civil Aviation Magazine, No. 7, 1990, p. 38-39). Tail stabilizers are made in the form of aerodynamic plates (keels) with a certain area installed parallel to (not at an angle) the side surfaces of the container in its rear part with a given extension for the upper edge and for the rear end. In addition to the tail stabilizers, a head plate is installed on the outside of the container. Its purpose is to create vortex flows in the head of the container and thereby reduce drag. The optimal dimensions of the head plate and the distance from the front end of the container are connected by certain dependencies with the dimensions of the container.

The flight tests carried out with us (in the PANKh NPK) in the process of working together with the authors confirmed their data that the stabilization tools they proposed were effective, but only when using the entire set of tools and only for one (estimated) load. So, when transporting an external container of the Mi-26 helicopter with a mass of 7.2 tons and dimensions of 8000 × 2800 × 2500 mm, the safe flight speed increased from 75 ... 80 km / h (without the above means) to 180 ... 200 km / h (with a full set of stabilization tools).

However, with separate use, the head plate and tail stabilizers are ineffective. When changing the configuration of the container, for example, by increasing the length without changing other sizes, the full set of tools (calculated and manufactured for the first version of the container) also proved to be ineffective.

In addition, with an increase in the angle of attack (α) and slip, the gain in decreasing the resistance from the head plate decreases and completely disappears at α = 25 °. Deviations of other parameters from the calculated ones (the offset and sizes of stabilizers, the offset and sizes of the head plate, etc.) significantly narrow the area of the track stability of the container.

The advantage of the device is the absence of high requirements for the quality of manufacturing of the head plate from ordinary rolled steel (a frame of corners, sheathed by a sheet). On the other hand, tail stabilizers manufactured by us using sophisticated modern technology (gluing from fiberglass using polyester resins) and having ideal surfaces and profiles did not produce tangible results when the container parameters or flight modes changed from the calculated ones.

The complexity of the design and the great complexity of manufacturing and installation (it took more than 3 hours to install the kit) significantly limit the scope of the known device.

In addition, the use of slings of the same length for hooking provides a zero angle of attack (α = 0) when lifting, but leads to a negative angle of attack of the container in flight and an increase in the load on the helicopter due to the appearance of negative lifting force.

The objective of the present invention is to improve the flight performance of a helicopter in flight with a parallelepiped type cargo on an external sling. This is achieved through the use of simpler and more affordable (less labor-consuming to manufacture) external stabilization means that prevent the buildup of cargo with an acceptable drag increment and, therefore, increase the safe flight speed.

The specified technical result in a device for transporting goods by helicopter, containing a container in the form of a parallelepiped with two tail stabilizers, equipped with nodes for hooking, and a set of slings of the external suspension, connected to the lock of the helicopter, is achieved by the fact that the tail stabilizers are made in the form of rotary wings attached to the rear end of the container by means of vertical hinges mounted on the side surfaces, both rotary flaps are installed with the possibility of either fixed of storage in the plane of the rear end, or turning and securing in the open position at an angle of 120 ... 180 ° to the side walls of the container before flight.

Rotary flaps can be made integral with additional plates attached by means of vertical hinges or without them.

The swing doors are locked in the open position by means of length-adjustable rods.

The slings of the external suspension of the helicopter can be made of different lengths, and the slings attached near the rear end are longer than the front slings to ensure that the helicopter tilts the longitudinal axis of the container to the horizon at an angle of 10 ... 35 °.

The invention is illustrated by drawings, where Fig. 1 shows a device with a helicopter, side view (the main lines depict the position of the container and slings when the helicopter is hanging, and thin - the position in flight); figure 2 is a view of the container from above; figure 3 and 4 are possible options for the implementation of the valves and additional plates (the main lines are shown in the closed position, and thin in the open position).

A device for transporting goods by helicopter 1 contains a container 2 in the form of a parallelepiped with nodes 3 hooks (loops, eyes, etc.). The structure of the device also includes spider slings 4, 5 and the central rope 6. Moreover, the slings 4 and 5 have different lengths. The flaps 8 are attached at the rear end of the container 2 by means of vertical hinges 7. To fix the flaps 8 on the sides of the container 2, rods 9 with length adjusters 10 are pivotally attached. With a large width of the container, the flaps 8 are made equal to half this size (Fig. 2). In this case, it is possible to use as doors the existing doors with locks on the rear end of heavy containers. This ensures the safety of the cargo when the container is in storage in the closed position. Sash 8 can be made integral. To this end, additional plates 11 are attached to the main leaf 8 by means of hinges identical to the hinges 7 (from the top in FIG. 4), and additional length-adjustable rods similar to the rods 9 (not shown). This makes it possible to vary the leaf length depending on the width and length of the container. For example, with a narrow container, the shutters 8 can be made over its entire width with the overlapping shutters during storage in a warehouse (Fig. 3). With a short and wide container, composite flaps with additional plates 11 are suitable for increasing the total length of the flaps (Fig. 4). It is possible to use shortened additional plates 11 attached directly to the leaves 8 without hinges (in Fig. 4, from below).

In addition, the container may be equipped with bottom wheels 12.

The proposed device operates as follows. Before use, the container 2 is loaded and rolled out on wheels 12 from the warehouse. The cargo inside the container is securely fastened (moored), as in normal air transport. Open the rear flaps and fix at the required angle to the side surfaces of the container. In the case of using the container as the doors of the rear doors, it is advisable to put a curtain on the rear end made, for example, from a parachute cover. By means of length-adjustable rods 9, an angle of 120 ... 180 ° is established between the cusps and the side surfaces of the container. If it is necessary to more accurately establish a stable position of the container in flight, use additional plates 11 on the wings 8. Using the position of the plates 11 (as additional aerodynamic surfaces - trim tabs), you can precisely control the angle of the container in flight. For this, the shortened plates 11 attached directly to the leaves 8 can be bent to one side or another (like plates on the trailing edge of an aircraft wing).

When the helicopter 1 hangs over the container 2 located on the ground or when landing nearby, slings 4 and 5 are hooked to the nodes 3, and the central rope 6 is hooked to the lock of the helicopter 1. After lifting by helicopter in hovering mode, the container 2 deviates from the horizontal by an angle α due to the difference the lengths of the slings 4 and 5 (see figure 1). The angle γ of the deviation of the central rope 6 from the vertical is zero, and the angle α between the longitudinal axis of the container and the horizon can be equal to 10 ... 35 ° (initial angle of attack).

With the acceleration of the helicopter 1 to a speed of 50 ... 60 km / h on the wings 8, air flow disruptions occur, which lead to a pressure drop on each wing. As a result, an aerodynamic force is generated on each leaf, which tends to turn the container in the opposite direction. With the dynamic balance of these forces, the longitudinal position of the container in flight is ensured due to the equality of the moments acting on the container. In case of imbalance of forces, for example, during a helicopter maneuver or a gust of wind, the container will deviate from the direction of flight. Turning the longitudinal axis of the container, for example, with the front end to the left, will cause a greater pressure drop on the right wing, and decrease on the left wing. As a result, a restoring moment arises, returning the container to its original position.

In addition, the presence of open flaps 8 in flight shifts back the center of pressure of the aerodynamic forces acting on the side surfaces relative to the center of mass of the container. The result is an additional stabilizing moment. Therefore, starting from a speed of 50 ... 60 km / h, the longitudinal axis of the container is stable in the direction of flight, even at large angles of attack α of the container.

With a set of speeds, the angle γ of the deviation of the central rope 6 from the vertical increases, and the angle α between the longitudinal axis of the container and the horizon decreases. As a result, the angle of attack α decreases from the critical values (15 ... 35 °) to the minimum (1 ... 10 °), and a lifting force arises that reduces the load on the helicopter from the weight of the container.

The flight tests performed on a Mi-8 helicopter with a container weighing 2.5 tons and dimensions of 5000 × 1000 × 2000 mm showed that the installation of pivoting doors (doors at the rear end) at an angle of 155 ... 160 ° ensures stabilization and track stability of the loaded container up to a speed of 160 ... 170 km / h, and empty (weight 700 kg) - up to 140 km / h. At the same time, the restriction on flight speed was only when the central rope touched the enclosure of the cargo hatch. In flight at such speeds, the load on the helicopter from the force of the weight of the container decreased according to the readings of the tractor by 500 kg due to the optimal angle of attack. The ability to control the position of the flaps along the installation angle allows you to achieve the position of the container in flight strictly in the direction of the incoming flow, which reduces drag.

Using the proposed device will ensure the efficient use of helicopter carrying capacity due to the lower material consumption of containers, as well as reducing the time to reduce the cost of finalizing containers by using structural elements, such as rear doors, etc., as stabilizing means.

The proposed device eliminates the buildup of cargo in flight with increased speeds and ensures the safe execution of operations for the delivery of goods on the external suspension of helicopters.

Claims (4)

1. A device for transporting goods by helicopter, containing a container in the form of a parallelepiped with two tail stabilizers, equipped with nodes for hooking, and a set of slings of the external suspension, connected to the lock of the helicopter, characterized in that the tail stabilizers are made in the form of rotary shutters attached to the rear end the container by means of vertical hinges mounted on the side surfaces of the container, the pivoting doors being mounted either to be fixed in the rear plane end face during storage, or turning and securing in the open position at an angle of 120 ... 180 ° to the side walls of the container before flight. 2. The device according to claim 1, characterized in that the pivoting flaps are made integral with additional plates attached with or without vertical hinges. 3. The device according to claim 1 or 2, characterized in that the rotary shutters are fixed in the open position by means of length-adjustable rods. 4. The device according to claim 1, characterized in that the slings of the external suspension of the helicopter are made different in length, and the slings attached near the rear end are longer than the front slings to ensure that the helicopter tilts the longitudinal axis of the container to the horizon at an angle of 10 ... 35 °.

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