Patent Application
20130299639
This application claims the benefit of the Spanish patent application No. 201230703 filed on May 10, 2012, the entire disclosures of which are incorporated herein by way of reference.
This invention refers to a communications system used during in-flight refueling of aircraft, between a tanker aircraft and a receiving aircraft.
For in-flight refueling operations, a known method is based on the use of a retractable tube device, commonly called a boom, intended for connecting a supply aircraft or tanker aircraft with a receiving aircraft, in flight. This device basically consists of a telescopic tube which is fitted to the bottom of the tanker aircraft by means of a joint unit, further comprising, at the other end a fuel feed nozzle by means of which the fuel passes to the receiving aircraft. This fuel feed nozzle connects to a receptacle in the receiving aircraft to make a proper the fuel transfer between the two aircraft.
The refueling operation requires that the receiving aircraft be in a precise and consistent position prior to the contact and at the contact itself. Therefore, reliable and precise communications need to be established between the receiving and tanker aircraft, by means of an appropriate communications system.
Equally fundamental during the in-flight refueling operation is detecting the moment that contact occurs between the two aircraft.
As such, the current communications system in in-flight refueling operations is based on two induction coils, one located in the tanker aircraft boom nozzle and the other in the receiving aircraft receptacle, such that the two coils, in the nozzle and receptacle, face each other when contact occurs between the two aircraft, such that circulation of connection pulses and audio data between said coils are enabled, defining the connection status between the two aircraft. Said known communications systems have been used since the first refueling aircraft developed in the nineteen-forties/fifties and have not undergone changes or seen progress in recent decades.
The problem posed by the known communications systems is that they are not as reliable as would be considered appropriate as they are based on induced, rather than direct, values. Additionally, the data transmitted between the two aircraft via audio can suffer distortion that would lead to creating hazardous situations in refueling operations.
Thus, in current communications systems, the indications of connection status between the nozzle and the receptacle take place by means of induced values in the two coils, in the receptacle coil (receiving aircraft) and the nozzle coil (tanker aircraft boom), in a similar manner to signals induced between the primary and secondary in a power transformer. A change in status of the refueling system occurs according to the receipt of a series of pulses. These pulses can be generated either by the receiving aircraft or the tanker aircraft.
However, in addition to knowing whether or not the nozzle is connected to the receptacle, it is also of interest to transfer other series of relevant data between the receiving and tanker aircraft. In this, the known communications systems also comprise an audio system which is responsible for transferring oral communications between the receiving aircraft's pilot and the tanker aircraft's refueling systems operator.
A limitation of the above system is that all communications take place orally, without the possibility of transmitting signals or information automatically which would improve information security, hence these systems can lead to erroneous or misunderstood communications, incorrect synchronization, etc.
However, radio frequency emissions (radio link, Wi-Fi, etc.) have the disadvantage that emissions of this type can also be detected by other aircraft or in certain control posts.
The present invention is intended to overcome the problems and disadvantages described above.
As such, this invention develops a communications system used in in-flight refueling of aircraft, in particular the in-flight refueling of a receiving aircraft using a tanker aircraft.
The communications system of the invention comprises a primary device for sending/receiving data on the nozzle of the retractable tube or boom of the tanker aircraft which connects to a secondary device for sending/receiving data on the receptacle of the receiving aircraft, such that said communications system transmits data only when the nozzle on the tanker aircraft retractable tube or boom and the receiving aircraft receptacle are connected to each other, i.e., only when the primary device for sending/receiving data on the retractable tube nozzle or boom and the secondary device for sending/receiving data on the receiving aircraft receptacle are facing each other and are also active or activated. In this way, the communications system of the invention provides the certainty that, when the fuel transfer operation between the tanker and receiving aircraft begins, the tanker aircraft nozzle is indeed connected in the receiving aircraft receptacle.
The communications system developed by the invention transmits data by means of digital signals, rather than the analog signals in the background technology, making these communications more reliable and robust. Furthermore, its construction is compatible with relative rotations between the tanker aircraft and the receiving aircraft. In the previous known technique, as described in background above, the receiving aircraft and tanker aircraft coils, i.e., in the receptacle and boom, need to be perfectly aligned faced each other for the data transmission to be correct. If the two coils had a relative displacement, data transmission would continue, although this transmission would not be correct. In the case of relative rotation between the tanker and receiving aircraft, the boom and receptacle coils would not be perfectly aligned opposite each other, thus the system using the previous technique would not be compatible with these relative displacements. However, the communications system developed by the invention, as it transmits data using digital signals of 0 s or 1 s, eliminates erroneous or defective transmissions, at the same time as being a system compatible with relative rotations between the two aircraft.
The following objects and many of the advantages of this invention can be appreciated more easily though a basic understanding of the details described above, in combination with the more detailed description that appears below along with the accompanying figures, where:
The invention develops a communications system used in in-flight refueling of aircraft, in particular the in-flight refueling of a receiving aircraft 10 by means of a tanker aircraft 20 as per the general arrangement shown in
The communications system of the invention comprises a primary device for sending/receiving data 201 on the nozzle 1 of the tanker aircraft 20 retractable tube or boom 2 and a secondary device for sending/receiving data 202 on the receiving aircraft 10 receptacle 3.
The communications system of the invention only transmits data when the nozzle 1 of the tanker aircraft 20 retractable tube or boom 2 and the receiving aircraft 10 receptacle 3 are connected, with the primary device for sending/receiving data 201 on the nozzle 1 and the secondary device for sending/receiving data 202 on the receptacle 3 perfectly aligned opposite each other as well as both devices 201 and 202 being active, or at least the two devices substantially opposite each other such that data transmission is possible. That is, the primary device for sending/receiving data 201 and the secondary device for sending/receiving data 202 are sufficiently well aligned facing each other and therefore permitting data transmission providing that the nozzle 1 is in a certain position or within a limited range of positions within the receptacle 3 (previously determined and defined positions such that the connection of the nozzle 1 in the receptacle 3 is such as to permit the function it is to perform, in particular the in-flight transfer of fuel between the two aircraft, 10 and 20). This indicates that the two aircraft 10, 20, are in the correct relative contact position, as this contact position is used for a dry training and maneuvering contact without fuel transfer or as an indication that marks approval to begin the operation to transfer fuel between the two aircraft, 10 and 20. This provides certainty that, when the operation between the tanker 20 and receiving aircraft 10 begins, the nozzle 1 is really connected in the receiving aircraft 10 receptacle 3.
The communications system of the invention operates with direct, rather than induced, signals between the primary device for sending/receiving data 201 and the secondary device for sending/receiving data 202 once the receiving 10 and tanker aircraft 20 are connected. Hence, the primary device for sending/receiving data 201 on the nozzle 1 and the secondary device for sending/receiving data 202 on the receptacle 3 preferably comprise infra-red communication components such as infra-red senders/receivers, preferably one infra-red sender 11 and three infra-red receivers 12, 13, 14 on the nozzle 1 (
In the background of the invention, represented in
The communications system of the currently disclosed invention preferably comprises, as represented in the outline in
As represented in
The attached Table I presents the configuration scheme for the infra-red senders/receivers 11, 12, 13 and 14 arranged on the nozzle 1, represented in
The functional arrangement of the configuration shown in
the information that the aircraft 10, 20 are connected is transmitted through the sender 11 and receiver 11′, said information reaching the receiving aircraft 10 through receiver 11′;
the information that the aircraft 10, 20 are connected is transmitted through the sender 12 and receiver 12′, said information reaching the tanker aircraft 20 through the receiver 12;
data buses of information are transmitted between the tanker 20 and receiving aircraft 10 by means of the receivers 13, 14 and the senders 13′, 14′, with this information being functionally redundant and separated, so as to provide the system with greater reliability.
The embodiment presented previously (
The attached Table II presents the operating protocol for the contact signals in the communications system of the present invention, taking into account that, as shown in
The attached Table III presents the data transmission arrangement (transmitted digitally, as can be seen in the attached table) between the tanker 20 and receiving aircraft 10, such that, by means of the infra-red senders 13′ and 14′, the receiving aircraft 10 sends information on its status to the tanker aircraft 20 via its infra-red receivers 13, 14:
As described previously, the data buses transmitted between the receiving aircraft 10 and the tanker aircraft 20 would be those shown below:
Receiving aircraft 10 identification: type of receiving aircraft 10 connected and registration or unique identifier of the receiving aircraft 10;
Speeds/accelerations of the receiving aircraft 10 in its six axes, enabling a load relief mode to be effected at the tip of the boom when connected based on information provided by the receiving aircraft 10, instead of by measuring the forces occurring in the tip of the retractable tube or re-fuelling boom;
Receiving aircraft 10 fuel tanks level, as well as overfill valve condition, which makes it possible to know when the receiving aircraft 10 filling is finishing so as to reduce the supply flow rate from the tanker aircraft 20 to the receiving aircraft 10, so reducing the pressure peaks in the fuel supply operation.
The communications system developed by the present invention also develops an electronic apparatus 400 which collects the information transmitted to systems 300 in the receiving aircraft 10, transforming this information by means of a selected protocol 200. As such, the electronic apparatus 400 in the receiving aircraft 10 collects the data coming from the secondary device for sending/receiving data 202, transforming this data by means of a selected protocol 200 and sending them to the systems 300 in the receiving aircraft 10. The block diagram showing the operating schema for this electronic apparatus is shown in
As is apparent from the foregoing specification, the invention is susceptible of being embodied with various alterations and modifications which may differ particularly from those that have been described in the preceding specification and description. It should be understood that I wish to embody within the scope of the patent warranted hereon all such modifications as reasonably and properly come within the scope of my contribution to the art.
| Number | Date | Country | Kind |
|---|---|---|---|
| 201230703 | May 2012 | ES | national |
