DE102022110505B3 - Pilot assistance for probe-and-drogue air refueling - Google Patents

Abstract

The invention relates to a system (1) for supporting a pilot of a manually controlled receiver aircraft (3) during aerial refueling by a tanker aircraft (5), having a display unit (7), a computing unit (9) and an interface (11) for determining a Relative speed between the tanker aircraft (5) and the recipient aircraft (3), the computing unit (9) being designed to control the display unit (7) in such a way that the relative speed is indicated by a display element (13) in or on a display unit (7 ) shown scale for the relative speed is displayed, the scale on the display unit (7) allowing positive and negative relative speeds to be displayed and areas of the scale being marked symbolically and/or in colour, and the display element (13) being displaceable along the scale and accompanied by is the magnitude of the relative speed.

Description

The invention relates to a system for supporting a pilot of a manually controlled receiver aircraft during aerial refueling by a tanker aircraft, and to an aircraft with such a system.

Air refueling is a frequently used concept to increase the range and flight duration of aircraft, especially combat aircraft. Fuel is transferred from a tanker aircraft in flight to the recipient aircraft through a pipe or hose. For this purpose, a corresponding relative position is assumed between the tanker aircraft and the recipient aircraft, which should be as constant as possible during the refueling process. Various systems are known in the prior art. Typically, however, all systems have in common that a pin is inserted into a funnel. While some systems have a spigot located on the recipient aircraft which must be inserted into a funnel located at the hose end of the tanker aircraft, in other systems a hose or pipe is routed from the tanker aircraft towards the recipient aircraft with a spigot on the hose end or pipe end inserted into inserted into a funnel of the recipient aircraft. Systems of the first type are usually referred to as "probe and drogue system" or "probe and basket system" or in the professional world also "probe and drogue" system. The systems of the second type include the so-called "flying boom" systems. In particular in such systems of the second type, a rigid tube with aerodynamic effective surfaces is typically guided from the tanker aircraft, with the outlet pin being arranged at the end of the rigid tube, which is inserted into a corresponding opening of the recipient aircraft with the aid of active control of the aerodynamic effective surfaces. For this purpose, an operator is typically positioned in the tanker with a view to the rear, who controls the boom with the tube by controlling the aerodynamic active surfaces. However, in systems of the first type, only a boom extends from the receiver aircraft with a pin at the end which must be inserted into the funnel or basket at the end of the tanker aircraft's hose. Typically, such a hose of the tanker does not have any aerodynamic effective surfaces, but is simply pulled behind the tanker, with the aerodynamic resistance of the basket in particular ensuring that the opening in the center of the basket is typically horizontal and causing the tank hose to move backwards from the tanker Tanker plane stretches.

The systems of the first type can typically be designed more cost-effectively than the systems of the second type, in particular those with aerodynamic active surfaces and an associated control system, because of the passively drawn hose behind the tanker aircraft and because of the relatively simple design of the basket. Systems of the first type rely solely on the receiver aircraft's flight guidance to establish a connection between the receiver aircraft's spigot and the tanker aircraft's hose basket. The disadvantage of this, however, is that the production of the connection between the trunnion, the receiver aircraft and the basket is difficult to achieve by manual flight guidance. In particular, since the tanker and receiver aircraft typically have different aircraft types and often different configurations (extreme example: a large tanker aircraft refueling a helicopter), the tanker aircraft and receiver aircraft often react differently to external disturbances such as gusts of wind. In addition, the receiver aircraft is typically located near the downstream of the tanker aircraft and can thereby be affected by its turbulent flow. The task for the pilot of the recipient aircraft is therefore associated with a high level of stress. The necessary close formation flight between tanker aircraft and recipient aircraft is of course risky and in the past has often resulted in damage to the recipient aircraft or to the basket of the hose of the tanker aircraft. The proposed solution to this problem described below is therefore particularly concerned with systems of the first type, i. H. with systems in which a pintle assembly is provided on the recipient aircraft and a hose with a basket at the end is extended from the tanker aircraft into which the recipient aircraft pintle is to be inserted prior to initiating the transfer of fuel from the tanker aircraft to the recipient aircraft.

The DE 34 40 812 A1 relates in this context to a control stand for a refueling device in a tanker aircraft for refueling another aircraft during flight, which is to be operated by an observer with operating levers for controlling a refueling pipe on the aircraft to be refueled and for extending and retracting the refueling pipe as well as with television cameras observation of the refueling process, whereby a) the control station with the observer's seat is accommodated on a refueling flap installed in the rear of the tanker aircraft; b) Displays for the fuel delivery rate, a viewing window and a television picture in the observer's line of sight screen are arranged; c) displays of the speed difference and the distance between the two aircraft, supplied by a radar device, can be reflected on the television screen and one of the images from three television cameras can be optionally switched on; d) operating devices and displays for controlling the refueling process, the fuel supply and for wireless and optical information for the pilot of the aircraft to be refueled are arranged on consoles arranged on both sides of the observer seat.

The DE 699 28 210 T2 further relates to a guide light device in operable relationship with a first aircraft to provide a pilot in a second aircraft with visual information regarding a position of the second aircraft relative to the first aircraft; the apparatus comprising: a 3-D camera system to generate a real-time 3-D video image of the second aircraft; a first memory to store at least one geometric model of at least one aircraft; selection means for selecting a stored geometric model based on the 3-D video image of the second aircraft; a display device to display the generated real-time 3-D video image and the selected geometric model; matching means for matching the displayed geometric model to the displayed real-time 3-D video image; a second memory to store predefined zone information; a processor to determine the position of the second aircraft relative to the stored zone information according to the adjusted geometric model and to generate control signals according to the determined position of the second aircraft; and guide lights mounted on the outside of the first aircraft to present position information visible to the pilot of the second aircraft according to the generated control signals.

The object of the invention is to make aerial refueling safer, in particular for a system of the first type described above (a so-called “probe-and-drogue” system).

The invention results from the features of the independent claims. Advantageous developments and refinements are the subject matter of the dependent claims.

A first aspect of the invention relates to a system for supporting a pilot of a manually controlled receiver aircraft during aerial refueling by a tanker aircraft, having a display unit, a computing unit and an interface for determining a relative speed between the tanker aircraft and the receiver aircraft controlled by the pilot, the computing unit to is designed to control the display unit in such a way that the relative speed is displayed by a display element in or on a scale for the relative speed displayed on the display unit, the scale on the display unit allowing positive and negative relative speeds to be displayed and areas of the scale symbolically and/or are colour-coded, and wherein the display element is displaceable along the scale in accordance with the magnitude of the relative speed.

The system is particularly, but not exclusively, useful when performing aerial refueling using a so-called "probe-and-drogue" system, in which a funnel, also called a basket, is attached to the end of a hose, and the hose is suspended behind a tanker aircraft being pulled against the air resistance of the basket and hose. The hose hanging from the tanker aircraft serves to transfer fuel from the tanker aircraft to the recipient aircraft. To do this, the recipient aircraft must reach the center of the basket with its fuel probe, the spigot, whereupon the spigot and basket are coupled, allowing fuel to be transferred through the hose to the receiver aircraft. This requires high flying skills and results in increased workload for the pilot of the recipient aircraft.

In order to reduce this workload, according to the invention, the current relative speed between the tanker aircraft and the receiver aircraft is displayed to the pilot on the display unit. The relative velocity information may come from one or more sources, for example the tanker aircraft wirelessly transmits its determined velocity to the receiver aircraft. As an alternative to this, a sensor unit suitable for this purpose can be arranged on the recipient aircraft, for example a Doppler radar, in order to continuously determine the relative speed between the recipient aircraft and the tanker aircraft; the time derivation of a distance measurement between receiver aircraft and tanker aircraft can also be formed continuously.

The computing unit is used to visualize this information for the pilot by appropriately controlling the display unit. For this purpose, a displaceable display element is shown on the display unit, for example a head-up display or a helmet visor. The position of the indicator relative to the scale on the display unit indicates the relative speed to the pilot. The scale preferably has numerical vertices and/or a current numerical value of the relative speed, for example in knots. For example, in the former case, the scale has a range of receiver aircraft separation speed from the tanker to 2 knots and receiver aircraft closing speed to the tanker to 7 knots, corresponding to a total relative speed range of -2 to +7 knots. The scale is intentionally dominated by positive relative speeds since the receiver aircraft typically approaches the cage from behind and thus has a positive relative speed when the refueling process is initiated. The relative speed is preferably updated continuously with the lowest possible latencies and at the shortest possible time intervals, ie as soon as new data on the relative speed is available, in order to give the pilot the impression of a continuous movement of the display element across the scale.

It is an advantageous effect of the invention that a pilot of the recipient aircraft is assisted with the information of the relative speed between the tanker aircraft and the recipient aircraft in an intuitively understandable manner. It is this relative speed that is critical to the success of connecting the tanker aircraft to the recipient aircraft for transfer of fuel to the recipient aircraft, as well as to avoiding damage to the recipient aircraft and to the hose or basket at the end of the hose. Such failed connection attempts or even damage occur in particular when the recipient aircraft approaches the tanker aircraft too quickly. Overshooting of the receiver aircraft beyond the basket towards the tanker aircraft can then occur, bringing the receiver aircraft dangerously close to the tanker aircraft or damaging the hose or basket along the way. The information about the relative speed makes it easy for the pilot of the recipient aircraft to see whether the recipient aircraft is currently approaching the tanker aircraft or moving away from it. This information is quite sufficient for the pilot to recognize whether he is also approaching or moving away from the basket at the end of the hose, which is being pulled behind the tanker aircraft, since the distance between the basket and the tanker aircraft can be assumed to be constant under all circumstances - after all the basket at the end of the hose has an approximately constant aerodynamic drag force and the hose is thus under constant tension. Alternatively, the change in the distance between the receiver aircraft and the basket over time can be determined directly, for example if a transmitter, marker or the like is arranged on the basket, or the relative speed of the receiver aircraft to the basket is determined using a Doppler radar.

According to an advantageous embodiment, the scale has differently colored zones. If a finite set of color zones is used, each of the zones preferably has a uniform color, but a continuous color transition can also be created, so that each of the zones also has a transition, with each of the zones preferably having a coherent color group in this case, for example, a transition from orange to red to purple, while the subsequent color zone includes purple and blue.

The computing unit is also advantageously designed to adapt the scale displayed on the display unit as a function of a tanker aircraft flying ahead. Slow-flying tanker aircraft tend to result in a scale with a smaller numerical speed range on the scale, while fast-flying tanker aircraft allow for a larger range.

According to a further advantageous embodiment, the display element is displayed in the respective color of that zone in or on which the display element is located. This advantageously makes it easier for the pilot to allocate the position of the display element to the associated location on the scale, so that clear information is transmitted to the pilot with regard to the current relative speed.

According to a further advantageous embodiment, the computing unit is designed to display the display element as a bar or arrow, with the scale being aligned vertically along a straight line and a positive relative speed being assigned to the upper end of the scale and a negative relative speed being assigned to the lower end of the scale , where a positive relative speed means a decrease in the separation between the receiver aircraft and the tanker aircraft and a negative relative speed means an increase in the separation. In this case, the scale is preferably displayed in the form of a bar with the scale direction along a vertical straight line.

According to a further advantageous embodiment, the location of the relative speed of zero is marked on the scale. This makes it easier for the pilot to dock the probe of his receiver aircraft with the hose end of the tanker aircraft, since he only has to assume a slightly higher speed above zero during the docking process in order not to approach the tanker aircraft too far.

According to a further advantageous embodiment, the location of the relative speed of zero is shown below half the height of the scale. Since the pilot approaches the tanker aircraft from behind with his receiver aircraft, he will naturally approach the tanker aircraft mainly at a positive relative speed until the fuel transfer is initiated, in order to reduce the distance to the tanker aircraft. Most of the time for the approach of the receiver aircraft to the tanker aircraft will therefore have a relative speed above zero, so that during this process the indicator can be expected to tend to be centered in the scale and only drop to zero on docking with the basket. This makes the display of the relative speed more intuitive.

According to a further advantageous embodiment, the display unit is a head-up display for reflecting the scale and the display element onto a projection screen in the cockpit of the recipient aircraft, or an active helmet visor.

According to a further advantageous embodiment, the computing unit is designed to hide the scale and the display element when the recipient aircraft is connected to the tanker aircraft in such a way that fuel can be transferred.

According to a further advantageous embodiment, the computing unit is designed to activate the display unit to display a flashing numerical value of the current relative speed when the display element reaches one end of the scale.

According to a further advantageous embodiment, the processing unit is designed to control the display in such a way that the display element is displayed flashing when the display element is in or at an uppermost zone of the scale. This serves as an additional warning to the pilot that he is approaching the tanker at a very high speed.

A further aspect of the invention relates to an aircraft with a system as described above and below.

Advantages and preferred developments of the proposed aircraft result from an analogous and analogous transfer of the statements made above in connection with the proposed system.

Further advantages, features and details result from the following description, in which at least one exemplary embodiment is described in detail-if necessary with reference to the drawing. Identical, similar and/or functionally identical parts are provided with the same reference symbols.

• 1: Eine mögliche Anordnung aus Tankflugzeug und Empfängerflugzeug beim Betankungsvorgang.
• 2: Ein System zur Unterstützung eines Piloten bei einer Luftbetankung gemäß einem Ausführungsbeispiel der Erfindung.
• 3: Das System nach 2 in einer beispielhaften Anwendung.

Show it:

• 1 : A possible arrangement of tanker aircraft and receiver aircraft during the refueling process.
• 2 : A system for assisting a pilot during aerial refueling according to an embodiment of the invention.
• 3 : The system after 2 in an example application.

The representations in the figures are schematic and not to scale.

1 shows an arrangement of tanker aircraft 5 and receiver aircraft 3 to illustrate a situation in which the system 1, as for example in 2 and 3 described, is used. The tanker aircraft 5 lying ahead is a transport aircraft with a corresponding tank module or a special tanker aircraft that is used for aerial refueling of combat aircraft. For this purpose, such a receiver aircraft 3 , an interceptor, flies up to the tanker aircraft 5 from behind and docks with its tank probe in the center of the basket at the end of the hose, which is pulled by the tanker aircraft 5 .

2 shows a system 1 for supporting a pilot during aerial refueling of a manually controlled receiver aircraft 3 by a tanker aircraft 5. This process is in 1 shown as an example. The system 1 has a display unit 7, a computing unit 9 and an interface 11 for determining a relative speed between the tanker aircraft 5 and the receiver aircraft 3 controlled by the pilot. The interface 11 for determining the respective current relative speed includes a radar unit that can determine a relative speed between the receiver aircraft 3 and the tanker aircraft 5 using the Doppler effect on the electromagnetic waves reflected by the tanker aircraft 5 (including its cage). This information is forwarded to the computing unit 9, which converts the information about the current relative speed into a display on the display unit 7. In the 2 the projection screen of a head-up display is shown, which visually superimposes the displayed information on the environment. Not shown in the 2 is the view of the tanker aircraft 5 flying ahead, clouds etc. for the sake of simplicity; the arithmetic unit 9 controls the display unit 7 in such a way that the Relative speed is displayed symbolically and with a certain accuracy also numerically by an arrow-shaped and vertically displaceable display element 13 along the vertically extending scale for the relative speed. The scale is labeled 'OS' for overtake speed and starts at the lower end with v1 at minus two knots, indicates zero relative speed at v0 and ranks further zones through v2 from one knot, v3 from five knots and v4 from seven knots down. The speed ranges within these numerically referenced speeds are colour-coded: Zone 'a' ranges from minus two knots to plus one knot and is shaded grey. Within this zone, the relative velocity from zero is specially marked with v0. The subsequent zone 'b' is marked in green and indicates the ideal approach speed to tanker aircraft 5. The overlying zone 'c' with higher relative speed is preferably filled in yellow or orange, the overlying zone 'd' is filled in red. The display element 13 is shifted along this graduated scale, depending on the magnitude of the currently determined relative speed. In this case, a positive relative speed indicates a reduction in the distance between the receiver aircraft 3 and the tanker aircraft 5 . A negative relative speed thus increasing the distance.

3 shows in the sub-images (A) to (F) a time course of a docking maneuver of the recipient aircraft 3 to the tanker aircraft 5. The line of sight from the cockpit is directed to the tanker aircraft 5 and thus corresponds to the view of the pilot of the recipient aircraft 3. In the respective left half of the picture is analogous to the representation of the 2 a vertical bar is shown to indicate the scale and labeled 'OS' for "overtake speed" analogous to the 2 designated. In partial image (A), the recipient aircraft 3 has a negative speed relative to the tanker aircraft 5, ie the recipient aircraft 3 is moving away from the tanker aircraft 5 at this moment. The display element 13 is therefore at the lower end of the scale. In partial image (B), the recipient aircraft 3 has already accelerated and currently has a relative speed of zero. In partial image (C), on the other hand, the receiver aircraft 3 has a positive speed, the non-visible display element 13 is located at the height of the tanker aircraft 5 in the green area of the scale. In partial image (D), the receiver aircraft 3 is approaching the tanker aircraft 5 very quickly, the display element 13 is already in the orange area. In partial image (E), the receiver aircraft 3 reaches such a high speed that the display element 13 is at the upper edge of the scale. Here, the arrow-shaped display element 13 flashes to draw the pilot's attention to excessive speed. The display element 13 together with the scale is hidden in partial image (F), since the receiver aircraft 3 is connected to the tanker aircraft 5 here in such a way that fuel can be transferred.

Although the invention has been illustrated and explained in more detail by means of preferred exemplary embodiments, the invention is not restricted by the disclosed examples and other variations can be derived therefrom by a person skilled in the art without departing from the protective scope of the invention. It is therefore clear that a large number of possible variations exist. It is also understood that the exemplary embodiments given are really only examples and should not be construed as limiting in any way the scope, applications or configuration of the invention. Rather, the preceding description and the description of the figures enable the person skilled in the art to concretely implement the exemplary embodiments, whereby the person skilled in the art, knowing the disclosed inventive concept, can make a variety of changes, for example with regard to the function or the arrangement of individual elements mentioned in an exemplary embodiment. without departing from the scope of protection defined by the claims and their legal equivalents, such as further explanations in the description.

Reference List

1

system

3

recipient aircraft

5

tanker plane

7

display unit

9

unit of account

11

interface

Claims (10)

System (1) for supporting a pilot of a manually controlled receiver aircraft (3) during aerial refueling by a tanker aircraft (5), having a display unit (7), a computing unit (9) and an interface (11) for determining a relative speed between the tanker aircraft (5) and the receiver aircraft (3) controlled by the pilot, the computing unit (9) being designed to control the display unit (7) in such a way that the relative speed is indicated by a display element (13) in or on a display unit (7) shown scale for the relative speed is displayed, the scale on the display unit (7) allowing the display of positive and negative relative speeds and areas of the scale symbolically and/or in color and wherein the display element (13) is displaceable along the scale in accordance with the magnitude of the relative speed. System (1) after claim 1 , where the scale has differently colored zones. System (1) after claim 2 , wherein the display element (13) is displayed in the respective color of that zone in or on which the display element (13) is located in each case. System (1) according to one of the preceding claims, wherein the computing unit (9) is designed to display the display element (13) as a bar or arrow, the scale being aligned vertically along a straight line and the upper end of the scale being assigned a positive relative speed and the lower end of the scale is assigned a negative relative speed, with a positive relative speed meaning a decrease in the distance between the receiver aircraft and the tanker aircraft (5) and a negative relative speed meaning an increase in the distance. System (1) according to one of the preceding claims, in which the location of the relative speed of zero is marked on the scale. System (1) according to the claims 4 until 5 , where the location of the relative velocity of zero is shown below halfway up the scale. System (1) according to one of the preceding claims, wherein the display unit (7) is a head-up display for reflecting the scale and the display element (13) onto a projection screen in the cockpit of the recipient aircraft (3), or an active helmet visor. System (1) according to one of the preceding claims, wherein the computing unit (9) is designed to hide the scale and the display element (13) when the receiver aircraft (3) is connected to the tanker aircraft (5) in such a way that a transmission of fuel is possible. System (1) according to one of the preceding claims, wherein the computing unit (9) is designed to activate the display unit (7) to display a flashing numerical value of the current relative speed when the display element (13) reaches one end of the scale. Aircraft with a system (1) according to one of the preceding claims.

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