GB1577604A

GB1577604A - Method for refuelling a helicopter or similar aircraft and a device for performing the method

Info

Publication number: GB1577604A
Application number: GB4333/78A
Authority: GB
Original assignee: STERNER AERO AB
Current assignee: STERNER AERO AB
Priority date: 1977-02-07
Filing date: 1978-02-02
Publication date: 1980-10-29
Also published as: FI59226C; FI59226B; SE7701323L; NO143095C; DE2803384A1; IT7812451A0; FR2379435A1; SE403998B; CA1084474A; IT1102991B; DK55778A; CH631400A5; FR2379435B1; NO143095B; DE2803384C2; NO780405L; FI780300A

Abstract

An additional container (9), which contains fuel for the helicopter, is attached to a container (5) which is suspended on a helicopter (1) and contains the load to be transported, for example a fertiliser. Said fuel can be pumped into the helicopter tank during flight. A second, identical container combination (5, 9) can be filled with the load and with fuel while the helicopter is away and can be picked up by the helicopter, in the hover, on its return, once the empty container combination has been detached. This allows the helicopter to carry with it in the container (9) only the fuel quantity required for one flight. Its own fuel tank carries only a fuel reserve. In consequence, the payload can be increased. <IMAGE>

Description

(54) A METHOD FOR REFUELLING A HELICOPTER OR SIMILAR AIRCRAFT AND A DEVICE FOR PERFORMING THE METHOD (71) We, STERNER AERO AB, a company organised under the laws of Sweden, of S-781 08, Borlange, Sweden, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- The present invention relates to a method and apparatus for refuelling a helicopter or similar aircraft.

When fetching or delivering a load, which is to be transported from one place to another by means of helicopter, it is preferable, for several reasons, to let the helicopter remain generally immobile in the air (hovering) while the load is connected to and disconnected from, respectively, a hook depending from the helicopter.

If the transportation route is relatively short and the helicopter repeatedly fetches and delivers goods without the helicopter having to be taken down to the ground and refuelled, the helicopter fuel tank must be provided with a large quantity of fuel before the first transport can be performed. A large quantity of fuel in the tank means that the helicopter will be heavy, which negatively influences its loading capacity.

To solve this problem it is, of course, possible to refuel the tank with a certain amount of fuel only and refuel the tank each time goods are fetched or delivered, whereby the refuelled amount is so chosen that it will be consumed during one transport. Such a refuelling, however, is difficult to perform while the helicopter is in the air because the distance between the filler socket and the ground often is great (depending on the vertical extension of the load and the suspension device). Moreover, such refuelling takes a long time.

According to one aspect of the present invention, there is provided a method of refuelling a helicopter or similar aircraft used to transport a sequential series of loads, depending from the aircraft, including the steps of detachably connecting a load and a tank containing fuel for driving the aircraft to the aircraft when it assumes a generally immobile position in the air near the ground, transferring the fuel from the tank to the aircraft when it is in the air, and, after the transport, when the aircraft assumes the generally immobile position in the air near the ground, exchanging the tank for another tank containing fuel for driving aircraft during a subsequent load transport.

According to another aspect of the present invention, there is provided apparatus for refuelling a helicopter or similar aircraft, including a load which is a container containing material to be dispensed when the aircraft is in the air and detachably connected to and depending from the aircraft, a tank containing fuel for driving the aircraft, the tank being mounted on the container in alignment with the flying direction of the aircraft, conduit means connecting the tank to the aircraft and means for directing fuel from the tank to the aircraft in order to transfer fuel to the aircraft when it is in the air.

A preferred embodiment of the invention will now be described with reference to the accompanying drawing in which: FIGURE 1 is a schematic side view of a flying helicopter with a transported load on which is mounted a fuel tank; and FIGURE 2 is a perspective view, seen from behind in the direction of flying, showing the load and the fuel tank in FIGURE 1.

In Figure 1 is shown a helicopter 1 to the underside of which is connected a wire 2 with a hook 3. The hook 3 detachably carries a load in the form of a fertilizer container 5 with a spreading device 4. The container 5 may be similar to the container shown in U.S. Patent application No. 4 099 676, for instance. The container 5, which also is provided with two stabilizing wings 6 and 7, directed obliquely backwards, and a motor 8 for driving the spreading device 4, contains fertilizer which is to be spread over a predetermined ground area. After the fertilizer material has been spread out from the container 5, the pilot takes the helicopter 1 to a station, for instance a station described and shown in the aforementioned U.S.

Patent, where the empty container is delivered and manually disconnected from the hook 3. An electric cable (not shown), having a bayonet coupling, for instance, is manually disconnected from the motor. This cable transmits signals from the pilot to the motor 8 to start the spreading device 4 when the helicopter is flying above the predetermined ground area.

A fuel tank 9 is detachably or permanently mounted on the rear of the container 5 between the wings 6 and 7, but can instead be mounted on the front side thereof. The tank is provided with an inlet/outlet connector 10 which is the female element in a bayonet coupling. When, or after, the empty container 5 is delivered at the station, the coupling is released between the female element 10 and a male element 11 which is connected to one end of a flexible tube 12, the other end of which being connected to the fuel tank (not shown) of the helicopter via a fuel filter 13.

After all the cables and flexible tubes between the helicopter 1 and the container 5 and the tank 9, respectively, have been disconnected, the helicopter flies forwards a short distance along the station until it is hovering above a second container with fertilizer which is identical with the container 5 and to which is detachably or permanently connected a second tank filled with fuel and identical to the tank 9. The second tank (9) has been refuelled and the second container (5) has been filled with fertilizer by ground personnel working at the station during the previous flight of the helicopter. The refuelling of the second tank (9) is performed by manually connecting a male element 15 to the female element 10.The male element 15 is identical with the male element 11 and is connected to a flexible tube which is connected to a fuel source (not shown) via a fuel pump 16. A valve in or between the element 10 and the tank ascertains that fuel is not discharged from the tank 9 when the refuelling has been finished and the coupling 10, 15 has been released.

When the helicopter is hovering above the second, filled container (5) with filled tank (9), the container is connected to the hook 3, the male element 11 is connected to the female element and the electric cable mentioned above is connected to the motor 8. As soon as these connections have been made, the helicopter 1 can climb and a pump 17, which is mounted adjacent to the helicopter tank and connected to the flexible tube 12, can be started. The pump 17 sucks fuel from the tank (9) just refuelled so that fuel is fed to the helicopter tank via the filter 13. Instead of arranging the pump adjacent to the helicopter tank, the pump can be mounted on the container 5 or on the tank 9 and can be a pressure pump. The pump can be driven electrically or hydraulically, or can be driven by the motor 8 or by the spreading device 4 if the pump is mounted on the container 5 or on the tank 9.In the case that the pump is driven by the motor 8 or by the spreading device 4, fuel is pumped into the helicopter tank at the time the spreading device 4 begins to work.

Instead of feeding the fuel to the helicopter tank it can be fed directly to the driving motor if this is suitable, and instead of using a pump the fuel can be fed by pressure or sucked up to the helicopter in another way, for instance by filling the tank with fuel and compressed air which pushes the fuel up to the helicopter tank when a valve between the tank and the helicopter tank is opened.

After the fertilising work and the refuelling have been performed, the helicopter is flown back to the station to deliver the empty container and fetch another container with a fuel tank. This container has been filled with fertilizer and the tank has been refuelled by the ground personnel at the station during the previous manuring work.

If, during the flight, the container 5, for some reason, must be dumped, the connection between the wire 2 and the helicopter 1 can be detached by the pilot by remote control. At the dumping, a break coupling 18 will be broken. Coupling 18 connects two ends of the flexible tube 12 which consists of two parts.

It should be understood that time will be saved and that the loading capacity will be increased by utilizing the example according to the invention. Thus, a minimum time is used for exchanging fertilizer containers because all the connections between the helicopter 1 and the container 5 and the fuel tank 9, respectively, are designed as bayonet couplings and no refuelling needs to be performed in connection with the container exchange. Because the helicopter tank always contains a small amount of fuel and is refuelled only with the amount of fuel consumed during a fertilising cycle, the container can be made large and the amount of fertilizer in the container can be increased, which decreases the costs for the fertilising work.

Of course, the invention is not limited to the embodiment described above and shown in the drawing. Other applications and several modifications of the invention are poss ible within the scopes of the claims. Thus, the method can be used whenever a helicopter or similar aircraft is to perform a number of transportations during the time it takes to empty the aircraft's tank. Examples of applications other than the application described above are the transportation of containers, filled with concrete, between a filling station and a building yard, whereby the concrete is discharged from the container at the building yard while a helicopter is hovering. The helicopter then returns to the station with the empty container to exchange this container for another container filled with concrete.The fuel tank which is permanently mounted or detachably mounted on the concrete container or detachably mounted on the helicopter is filled and emptied in the manner described above in connection with the fertilizer container.

WHAT WE CLAIM IS: 1. A method of refuelling a helicopter or similar aircraft used to transport a sequential series of loads, depending from the aircraft, including the steps of detachably connecting a load and a tank containing fuel for driving the aircraft to the aircraft when it assumes a generally immobile position in the air near the ground, transferring the fuel from the tank to the aircraft when it is in the air, and, after the transport, when the aircraft assumes the generally immobile position in the air near the ground, exchanging the tank for another tank containing fuel for driving the aircraft during a subsequent load transport.

2. A method in accordance with claim 1, including the step of transferring the fuel from the tank to the aircraft under pressure.

3. A method in accordance with claim 1, including the step of transferring the fuel from the tank to the aircraft under a vacuum.

4. A method in accordance with claim 1, including the step of connecting the tank to the aircraft via the load.

5. Apparatus for refuelling a helicopter or similar aircraft, including a load which is a container containing material to be dispensed when the aircraft is in the air and detachably connected to and depending from the aircraft, a tank containing fuel for driving the aircraft, the tank being mounted on the container in alignment with the flying direction of the aircraft, conduit means connecting the tank to the aircraft and means for directing fuel from the tank to the aircraft in order to transfer fuel to the aircraft when it is in the air.

6. Apparatus in accordance with claim 5, in which the tank is detachably connected to the load.

7. Apparatus in accordance with claim 5, in which the tank is permanently connected to the load.

8. Apparatus in accordance with any of claims 5 to 7, including a pump for feeding the fuel from the tank to the aircraft through said conduit means.

9. Apparatus in accordance with any of claims 5 to 8, in which the conduit means includes a bayonet coupling for readily uncoupling the conduit means.

10. A method of refuelling a helicopter or similar aircraft, substantially as herein described with reference to the accompanying drawing.

11. Apparatus for refuelling a helicopter or similar aircraft, substantially as herein described with reference to the accompanying drawing.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. ible within the scopes of the claims. Thus, the method can be used whenever a helicopter or similar aircraft is to perform a number of transportations during the time it takes to empty the aircraft's tank. Examples of applications other than the application described above are the transportation of containers, filled with concrete, between a filling station and a building yard, whereby the concrete is discharged from the container at the building yard while a helicopter is hovering. The helicopter then returns to the station with the empty container to exchange this container for another container filled with concrete.The fuel tank which is permanently mounted or detachably mounted on the concrete container or detachably mounted on the helicopter is filled and emptied in the manner described above in connection with the fertilizer container. WHAT WE CLAIM IS:

1. A method of refuelling a helicopter or similar aircraft used to transport a sequential series of loads, depending from the aircraft, including the steps of detachably connecting a load and a tank containing fuel for driving the aircraft to the aircraft when it assumes a generally immobile position in the air near the ground, transferring the fuel from the tank to the aircraft when it is in the air, and, after the transport, when the aircraft assumes the generally immobile position in the air near the ground, exchanging the tank for another tank containing fuel for driving the aircraft during a subsequent load transport.