DE102023130004B3 - stealth aircraft - Google Patents

Abstract

A stealth aircraft (1) with an aerodynamic and stealth-optimized airframe (2). The stealth aircraft (1) has a delivery shaft (3) which is arranged in the airframe (2) in order to prepare a drop of a load (4) to be dropped from the stealth aircraft (1) during flight operation of the stealth aircraft (1). The stealth aircraft (1) has an outlet (6) which connects the delivery shaft (3) to a rear upper side (B) of the airframe (2). The stealth aircraft (1) has a control unit (17) which is designed to control the outlet (6) in order to drop the load (4) from the delivery shaft (3) via the outlet (6). The outlet (6) is arranged on the airframe (2) in order to drop the load (4) via the upper side (B) of the airframe (2).

Description

TECHNICAL FIELD

The invention relates to a stealth aircraft having the features of the preamble of claim 1, as well as a method for operating a stealth aircraft and a computer program therefor.

The following background is intended only to provide information necessary to understand the context of the inventive ideas and concepts disclosed herein. Therefore, this background section may contain patentable subject matter and should not be considered prior art per se.

STATE OF THE ART

DE 10 2004 029 487 A1 discloses an aircraft having a fuselage with a landing gear arranged on the underside of the fuselage and with an upper side of the fuselage arranged opposite thereto, wherein a weapon carrier device is arranged on the upper side of the fuselage and the weapon carrier device is arranged in the cross-section of the fuselage at the location of the main landing gear above the landing gear bays of the main landing gear and above the engine flow channel, the aircraft having a flight computer device with a control and mission function and an actuating device for moving control surfaces for controlling the aircraft, wherein the control and mission function has a flight guidance function for guiding the aircraft to a target point or drop-off point and a weapon drop-off function for dropping at least one weapon that can be carried in the weapon carrier device based on a specification, and wherein the aircraft has a function assigned to the control and mission function and a flight attitude sensor system with which the aircraft can be rotated about its longitudinal axis xf so far that a component of the resulting buoyancy force from the bottom of the fuselage runs against the direction of gravity.

DE 10 2011 106 348 A1 discloses a low radar signature aircraft having a first side on which turbine openings and payload or landing gear bays are located. A second side of the aircraft is designed to have a lower radar signature than the first side.

CN 1 02 328 746 B also refers to stealth aircraft.

US 2018 / 0 362 163 A1 relates to an aircraft comprising a launch tube extending at least along a portion of the length of a wing of the aircraft and through which an object can be released from the aircraft. The launch tube comprises an opening at a distal end of the wing.

BACKGROUND

Stealth aircraft are specially designed aircraft that aim to minimize their detection by external sensors (e.g. electromagnetic, acoustic sensors). These aircraft are designed for military purposes and are characterized by their stealth technologies that allow them to minimize electromagnetic, acoustic and other signatures, making them harder to detect by enemy detectors. Stealth aircraft are often capable of carrying out surprise attacks and secret reconnaissance missions.

Of particular importance for stealth properties is the radar cross section (RCS), which is the measure of an object's ability to reflect radar beams. The larger the RCS of an object, the easier it is to detect by radar. Stealth aircraft are designed to minimize their RCS, which means that they are only very faintly or not at all visible to radar systems. This is done through special designs, shapes, surface finishes and materials that minimize radar reflection.

Measures to reduce radar cross section in stealth aircraft include the use of absorbent materials that absorb the radar beams and aircraft surface design, particularly minimizing openings and gaps to minimize retro-reflections. These aircraft often use stealth coatings and aerodynamic shapes to reduce RCS. In addition, radar shielding and special techniques such as internal or fully enclosed weapon mounts can be used to optimize stealth characteristics.

When dropping cargo over enemy territory, maintaining RCS is particularly important, as an increased RCS increases the likelihood of detection and attack. Stealth aircraft are designed to maintain their stealth characteristics even during such operations. When opening the cargo bay, the same principles and techniques must be applied to ensure that the RCS is minimized. This can be achieved by clever design of the cargo bay and the use of absorptive materials must be obtained in order to complete the mission successfully and discreetly.

The invention is based on the object of improving the stealth aircraft in its camouflage function during use, in particular during load shedding.

SUMMARY

This summary is intended to introduce a selection of features and concepts of the invention that are discussed later in the specification. This summary is not intended to identify important or essential features of the claimed subject matter, nor is it intended to limit the scope of the claimed subject matter.

According to the invention, the above-mentioned object is solved by the features of the independent claims.

Specifically, the task is solved by a stealth aircraft. The stealth aircraft has an aerodynamic and stealth-optimized airframe. The stealth aircraft has a discharge chute. The discharge chute is arranged in the airframe to prepare for the dropping of a load. The load is to be dropped from the stealth aircraft when the stealth aircraft is in flight. The stealth aircraft has an outlet. The outlet connects the discharge chute to a rear (or backwards-facing) top side of the airframe. The stealth aircraft has a control unit. The control unit is designed to control the outlet in order to drop the load from the discharge chute via the outlet. The outlet is arranged on the airframe in such a way that the load can be dropped over the top of the airframe, preferably backwards in the direction of flight.

The invention has the advantage that the RCS of the stealth aircraft is kept low over the duration of the mission. Because the release takes place over the top, a radar located below the stealth aircraft on the ground or in another aircraft (whether monostatic or bistatic) cannot detect the RCS change usually caused by a cargo hold that is opened downwards. The invention has the additional advantage that the acoustic and optical signatures that arise from the opening of conventional cargo hold flaps on the underside of the aircraft can be avoided. The invention also has the advantage that the change in the aerodynamic properties of the aircraft that arises from the opening of conventional cargo hold flaps on the underside of the aircraft can be avoided. The invention has the additional advantage that the conventional cargo hold flaps in the underside of the aircraft, which are exposed to high aerodynamic forces when opened, can be omitted, thereby saving weight.

Advantageous embodiments of the invention are specified in the subclaims.

The stealth aircraft may have an inlet. The inlet may connect the discharge chute to a forward (or forward-facing) top of the airframe. The control unit may be configured to control the inlet and the outlet to discharge the load from the discharge chute via the outlet. The inlet may be arranged and configured on the airframe such that an air flow into the discharge chute caused by the flight operation of the stealth aircraft (from the front in the direction of flight) provides a pressure, preferably pneumatic. The pressure may cause or contribute to the load being pushed through the outlet (backwards in the direction of flight) to discharge the load via the (rear or rearward-facing) top of the airframe (preferably an outlet opening at the end of the outlet).

Consequently, a mechanically simple mechanism for dropping loads from the stealth aircraft can be provided.

The pressure difference between inlet and outlet during load shedding can be greater than 2 times (or 3 times, 4 times or 5 times) the atmospheric pressure prevailing in the stealth aircraft's environment.

The inlet can have an inlet flap. The inlet flap can be designed to be operated in two operating positions, OPEN and CLOSED. The outlet can have an outlet flap. The outlet flap can be designed to be operated in the two operating positions, OPEN and CLOSED. The inlet flap and/or the outlet flap can be flush with a surrounding fuselage surface of the stealth aircraft in the CLOSED operating position and can be covered with the same material, for example.

For this purpose, the inlet can have an inlet flap motor. The outlet can have an outlet flap motor. The control unit can be designed to provide a release signal to both the inlet flap motor and the outlet flap motor in order to initiate the simultaneous opening and closing of the corresponding inlet flap and outlet flap. The control unit can also be designed to first To control the flap motor and, when the inlet flap is in the OPEN operating position, then to control the exhaust flap motor to bring the exhaust flap into the OPEN operating position.

The inlet may further comprise an inlet channel. The inlet channel may be provided as a ram air channel. The inlet channel may provide a direct air supply connection from the inlet flap to the discharge duct.

The outlet may further comprise an outlet duct. The outlet duct may provide a direct air discharge connection from the discharge duct to the outlet flap.

When both the inlet door and the exhaust door are in the OPEN operating position, direct air communication between the forward upper surface and the aft upper surface through the airframe can be provided.

Thus, dynamic pressure can be used to provide a simple mechanism for dropping loads from the stealth aircraft.

The inlet flap and the exhaust flap may each be aligned with the top of the airframe in the CLOSED operating position. The inlet flap may be aligned with the forward top of the stealth aircraft in the CLOSED operating position. The exhaust flap may be aligned with the rear top of the stealth aircraft in the CLOSED operating position. The airframe may preferably be an airframe or fuselage.

By aligning and flush closing all openings, all aerodynamic and camouflage properties of the stealth aircraft can be maintained.

The stealth aircraft can also have one or more aircraft engines for moving the stealth aircraft in the air. The exhaust flap and the one or more aircraft engines can be arranged on the airframe in such a way that the (already ejected or discarded) load of exhaust gases from the aircraft engine remains unaffected. In particular, the exhaust flap can be arranged between the aircraft engines, for example in the middle between two equally spaced aircraft engines.

This ensures the stealth characteristics of the stealth aircraft.

For example, the aircraft engine can form part of the inlet or part of the inlet channel. In this case, part of the inlet channel can correspond to an aircraft engine inlet channel, preferably a serpentine inlet channel. The inlet flap can be arranged in or on the aircraft engine inlet channel. The inlet flap can be a connecting piece between the other part of the inlet or the other part of the inlet channel and the aircraft engine inlet channel. In the OPEN operating position, the other part of the inlet channel or the other part of the inlet channel and the aircraft engine inlet channel can communicate in terms of air technology. In the CLOSED operating position, the other part of the inlet channel or the other part of the inlet channel and the aircraft engine inlet channel can be watertight, airtight and/or hermetically separated from one another. The intake duct can consist of one part and the other part of the intake duct, which can be divided by the intake flap. The same applies to the other aircraft engine in the case of two aircraft engine intake ducts, in particular those arranged symmetrically to the cockpit.

The control unit can be designed to control the inlet and the outlet during flight operation of the stealth aircraft for load shedding such that the outlet flap and the inlet flap are simultaneously in the OPEN operating position in order to shed the load from the discharge chute on the (rear) upper side of the stealth aircraft by means of an air flow through the inlet channel caused by the flight operation in the direction from the inlet to the outlet.

In this way, an energy-efficient drop technology with few moving parts and high operational reliability can be provided, which at the same time ensures the stealth aircraft's camouflage properties.

The pressure, which can be provided in whole or in part as aerodynamic dynamic pressure when the inlet flap is open, for example, can be designed or used by means of a sabot attached to the load, so that the dropping of the load does not require any further energy or additional electrical and/or mechanical (force effect) means or techniques. The sabot can be designed in such a way that it separates itself from the load automatically after the load is dropped through the effect of aerodynamic forces. The use of a sabot can thus make a compression device described below superfluous in any case and/or reduce the diameter of the inlet. The inlet or an associated inlet opening can be designed with regard to the sabot and/or a target speed of the stealth aircraft at the time of the load drop.

This can reduce costs and the risk of disruption while improving performance.

The stealth aircraft can also have an air pressure sensor. The air pressure sensor can be designed to measure the pressure prevailing in the discharge shaft, in particular provided by the air flow into the discharge shaft. The measurement can be carried out continuously, periodically, (irregularly) regularly, step by step or at intervals.

For example, the barometric pressure sensor can be powered or turned on when the navigation data indicates that the stealth aircraft is approaching the target area. As long as the navigation data indicates that the stealth aircraft is outside the target area, the barometric pressure sensor can be de-powered or turned off.

The stealth aircraft can further comprise, for example as an auxiliary or supporting device, a compressor device. The compressor device can be designed to generate compressed air (also called compressed air). The stealth aircraft can further comprise a compressed air channel. The compressed air channel can be arranged between the compressor device and the discharge shaft. The compressed air channel can be arranged to guide the compressed air generated by the compressor device into the discharge shaft and/or to supply the discharge shaft with the compressed air.

The control unit can be designed to set a pressure value of the compressor device based on a difference between a target pressure value of the discharge shaft and the pressure in the discharge shaft measured by the air pressure sensor. The compressor device can be designed to generate the compressed air with the set pressure value.

The control unit can also be designed to adjust a flow area of the inlet channel (e.g. at the inlet flap) depending on the difference between the target pressure value of the discharge shaft and the pressure in the discharge shaft measured by the air pressure sensor.

The target pressure value of the discharge chute should be a value that ensures detachment of the load from the stealth aircraft.

The pressure value and/or the flow area can be adjusted continuously, periodically, regularly, step by step, at intervals or in pulses. For example, the compressed air can be adjusted only briefly per load shedding. The same can apply to the flow area.

This allows for optimized, and if necessary accelerated, drop behavior of the load.

The stealth aircraft can also have a cargo hold. The cargo hold can have one or more loading flaps arranged on an underside of the airframe. The one or more loading flaps can extend along a longitudinal axis of the stealth aircraft. The load to be dropped (on the ground) can be loaded into the stealth aircraft via the one or more opened loading flaps (see above for opening the cargo hold, which is also referred to here as the cargo hold). The load is to be loaded into the cargo hold or is stored there.

Thanks to the techniques presented here, the loading flaps can be fitted with simple hinges and without any special reinforcements, since they are only operated when stationary on the ground and are therefore not subject to aerodynamic forces, as is the case with conventional loading flaps when the loading flaps are open in flight. After loading on the ground, the loading flaps of the stealth aircraft described here can also be sealed if necessary in order to close all gaps and thus optimise the stealth properties of the underside of the fuselage.

The stealth aircraft may further comprise a magazine. The magazine may be configured to rotatably or linearly store the load to be jettisoned between the cargo hold and the discharge chute. From the discharge chute, the load may be released to the outlet (based on a signal from the control unit (for example, according to navigation data, as described below). The control unit may be configured to keep the one or more cargo hold loading doors closed during flight operations.

This can support the reliability of the camouflage property.

The above-mentioned object is also achieved by a method for operating a stealth aircraft. The stealth aircraft has an airframe with an aerodynamic design and an integrated discharge shaft. The stealth aircraft also has a control unit. The method includes providing, by means of a magazine, a load to be dropped in the discharge shaft as long as navigation data provided to the control unit do not indicate a target area for dropping the load. The method includes actuating, by the control unit, an outlet, as soon as the navigation data indicate the target area for dropping the load, in order to drop the load from the discharge shaft, by means of a pressure in the discharge shaft, above the stealth aircraft. Here, dropping can also include ejection. The ejection here can mean a pressurized ejection/dropping, preferably independent of gravity.

The method may include providing or initiating, by the control unit, a ram air channel between the delivery chute and a closable inlet flap provided on a top of the airframe, as soon as the navigation data indicates the target location area for jettisoning the load, in order to jettison the load from the delivery chute, by means of a flow in the ram air channel, above the stealth aircraft.

Expressions such as “above” or “top” refer to the side of the stealth aircraft facing away from the earth’s surface.

The above-mentioned object is also achieved by a computer program. The computer program comprises instructions which, when the computer program is executed by a computer, cause the computer to carry out or initiate a method for operating a stealth aircraft or steps thereof. The stealth aircraft has an airframe with an aerodynamic design and an integrated delivery shaft. The method comprises providing or storing, by means of a magazine, a load to be dropped in the delivery shaft as long as navigation data provided to the computer do not indicate a target area for dropping the load. The method comprises actuating or initiating, by the computer, an outlet as soon as the navigation data indicate the target area for dropping the load, in order to drop the load from the delivery shaft by means of a pressure (preferably provided by compressed air and/or ram air) in the delivery shaft above the stealth aircraft.

The method may include providing or initiating, by the computer, a ram air channel between the delivery chute and a closable inlet door provided on a top of the airframe, when the navigation data indicates the target area for jettisoning the load, to jettison the load from the delivery chute, via a flow in the ram air channel, above the stealth aircraft.

The navigation data can be Global Navigation Satellite Systems (GNSS) coordinates (GPS, Glonass, Galileo, etc.). The GNSS coordinates can refer to position data, and include longitude, latitude, and altitude. Longitude can indicate position east or west of the prime meridian, measured in degrees. One degree (°) can be divided into 60 minutes of arc ('), and each minute of arc can be divided into 60 seconds of arc (’’). Latitude can indicate position north or south of the equator, measured in degrees. Altitude (ellipsoidal altitude or geoidal altitude) can indicate the height of a point above the Earth's ellipsoid, above the Earth's ground, or with respect to sea level, measured in meters, feet, or another unit of measurement. Degrees and arc seconds (gon, gon = 1/400 of a degree) can of course also be used for longitude and latitude.

The computer program may, for example, be a module for starting/operating the stealth aircraft or the control unit as described herein.

The above task is also achieved by a data carrier. The computer program can be stored on the machine-, processor- or computer-readable data carrier, such as on a permanent or rewritable storage medium. This also includes the fact that the computer program can be made available for download on a server or a cloud server, e.g. via a data network such as the Internet or a communication connection such as a wireless connection.

In other words, the invention relates to aerodynamic load shedding in stealth aircraft. For example, a closable ram air supply is formed via a closable air inlet. A compressed air supply can optionally be provided. The ram air supply, and optionally the compressed air supply, can be used to drop a load over the rear upper part of a stealth bomber. The load can be rotatably provided or stored in a rotating magazine (drum). This means that a large shaft opening or cover flap on the underside of the fuselage can be omitted, thus saving weight. For example, this can result in no change in the aerodynamics during the drop. This means that, for example, there can be no change in the signature of the underside of the fuselage during the drop (radar signature, acoustic signature, stealth, camouflage). The drop or ejection of the payload can be generated by an aerodynamic force, for example exclusively. The aerodynamic force can result from the ram pressure from the front and/or the suction from the rear. An amplification of the force can be achieved by a, preferably inverted, sabot (itself inverted) or a pneumatic impulse. The sabot can therefore be mounted upside down on the load, in particular at a rear end of the load.

Although some of the aspects described above relate to the stealth aircraft, the control unit, the method or the computer program, these aspects may also apply to the other aspects thereof.

In one example, the control unit may be implemented using hardware circuits, software means, or a combination thereof. For example, multiple units of the control unit may each be implemented in a single physical unit, for example when multiple functions are implemented in software. The units of the control unit may also be implemented in hardware components. The units of the control unit are each to be understood as functional units that are not necessarily physically separated from one another. For example, the control unit may be implemented at least partially as a computer, field programmable logic array (FPLA), field programmable gate array (FPGA), microcontroller, CPU (e.g. with multiple cores), graphics processing unit (GPU), application specific integrated circuit (ASIC), and/or digital signal processor (DSP).

All technical and scientific terms used herein have the meaning that corresponds to the general understanding of the person skilled in the art in the technical field of aerospace technology; they are to be interpreted based on the definitions found in the dictionary or the technical jargon of this technical field. If technical terms are used incorrectly and thus do not express the technical idea of the present invention, they can be replaced by technical terms that give the person skilled in the art a correct understanding.

The terms "first" and "second" are intended to simply differentiate components from one another. For example, a first component can be referred to as the second component and a second component as the first component. It should be noted that these terms and all numerical indications ("one", "two", etc.) are not to be understood as exhaustive for the scope of protection, but are also exhaustive for the disclosure content. For example, the expression "two ABC" can mean either "exactly two ABC" or "two or more ABC".

If it is said here that a component is "connected" to or "communicates" with another component, this can mean for the purposes of the present disclosure that these components can also be directly connected to one another or can communicate with one another. The term "directly" indicates that there is no further component in between.

The process steps described herein should not be interpreted as requiring that they be performed in a particular order, unless expressly or implicitly stated otherwise, for example if these process steps cannot be interchanged for technical reasons. The process steps may also be performed directly one after the other (without any further intervening steps) and/or continuously.

BRIEF DESCRIPTION OF THE DRAWINGS

• 1 eine schematische Darstellung eines Längsschnitts eines Tarnkappenflugzeugs;
• 2 eine schematische Ansicht eines Verfahrens zum Betreiben des Tarnkappenflugzeugs; und
• 3 eine schematische Ansicht einer Steuereinheit des Tarnkappenflugzeugs.

Further objects, features, advantages and possible applications will become apparent from the following description of non-limiting embodiments with reference to the accompanying drawings, in which:

• 1 a schematic representation of a longitudinal section of a stealth aircraft;
• 2 a schematic view of a method for operating the stealth aircraft; and
• 3 a schematic view of a control unit of the stealth aircraft.

The reference symbols used in the drawings and their meanings are summarized in the list of reference symbols at the end of this description. The same or similar components in the drawings are always provided with the same or similar reference symbols. Detailed explanations of known functions and structures are omitted if they detract from the invention.

DETAILED DESCRIPTION

The stealth aircraft and the method of operating the same and the computer program therefor will now be described with reference to the embodiments. Without being limited thereto, specific details are set forth in order to provide a deeper understanding of the invention.

In addition, spatially relative descriptors such as "bottom" or "top" and the like may be used herein to easily describe the relationship of the components shown in the drawings to one another. The spatially relative descriptors are intended to additionally describe other orientations of the device in use or in operational stealth aircraft. The stealth aircraft may be oriented differently (rotated 90 degrees or in another orientation), and the spatially relative descriptors used herein may be interpreted accordingly.

1 shows a schematic representation of a longitudinal section of a stealth aircraft 1. The stealth aircraft 1 has an airframe 2 with an upper side AB and a lower side C, which are aerodynamically and stealth-technically optimized. The upper side AB is essentially divided into a front upper side A and a rear upper side B. A first dimension of the rear upper side B can be greater than 1 time (or 1.5 times or 2 times or 3 times) of a second dimension of the front upper side A. The first and second dimensions can each be dimensions running in the longitudinal direction (along the longitudinal axis or roll axis) of the stealth aircraft 1 and together result in an aircraft upper side length running along the roll axis. A third dimension of the lower side C can correspond to an aircraft lower side length running along the roll axis and be less than 1 time (or 0.9 times or 0.8 times) of the aircraft upper side length running along the roll axis.

In 1 the direction of flight F is also shown, since the stealth aircraft 1 flies forward during operation. An essential component is the discharge duct 3 integrated in the airframe 2. The discharge duct 3 can be pressurized before operation. In any case, the discharge duct 3 is isolated from the external environment of the stealth aircraft 1 before the load 4 is dropped (here with a preferably inverted sabot 5) or when the outlet flap 7 of the outlet 6 is closed. In other words, the discharge duct 3 in this case is watertight, airtight and/or hermetically sealed. The outlet 6 is arranged in a rear upper area of the airframe 2. When the outlet flap 7 is open, the load 4 is discharged or ejected from the discharge duct 3 via the outlet channel 8.

The discharge shaft 3 can be pressurized P with the aid of the inlet 9 and/or the compressor device 15. The inlet 9 has an inlet flap 10 which can be opened or closed at the same time as the outlet flap. When the inlet flap 10 is open, an air flow caused from the front in the direction of flight F through the inlet channel 11 can provide a pressure P in the discharge shaft 3. This pressure P in the discharge shaft 3 can also be provided by the compressor device 15 connected to the discharge shaft 3 via a compressed air channel 16 (for example, if there is no inlet 9). Likewise, if there is an inlet 9, the compressor device 15 can also be used in addition to achieve a target pressure value predetermined for the release if the pressure P generated by the inlet channel indicates that additional pressure is required. Also, if the compressor device 15 is present, the inlet 9 can additionally be used to achieve the target pressure value predetermined for the discharge if the pressure P generated by the compressor device 15 indicates that additional pressure is required.

In order to measure the pressure P in the discharge shaft 3, an air pressure sensor 14 is used, which communicates with the control unit 17. The control unit 17 takes on the role of the central control unit in the stealth aircraft 1, as described below. The control unit 17 thus takes over the control of the essential components, in particular the inlet flap 10, the outlet flap 7, the magazine 13, the compressor device 15 and/or the loading flap(s) 12. The control unit can also use the air pressure sensor 14 continuously, periodically, (irregularly) regularly, step by step or at intervals.

The delivery shaft 3 can extend in the direction of the longitudinal axis of the stealth aircraft 1. For example, the delivery shaft 3 can be arranged centrally and/or symmetrically to the longitudinal axis of the stealth aircraft 1.

The load 4 (with optional sabot 5) can be loaded into the stealth aircraft 1 via one or more open loading flaps. For this purpose, a rotating magazine 13 is available, for example, to accommodate the load 4 in order to load the delivery shaft 3 with a load 4 to be dropped. The magazine 13 can rotate about the longitudinal axis or perpendicular to it, and can be arranged centrally in the stealth aircraft 1, for example. The loading flap(s) 12 are never opened during operation of the stealth aircraft 1. This prevents a changed signature.

2 shows, in relation to 1 , a schematic view of the method S0 for operating the stealth aircraft 1. The method S0 in 2 describes in general terms the operation of the stealth aircraft 1, in which, in S1, the magazine 13 provides the load 4 to be dropped in the delivery shaft 3 as long as the navigation data provided to the control unit 17 does not indicate a target area for dropping the load 4. As soon as the navigation data indicate the target area for dropping the load 4, the control unit 17 actuates the outlet 6 in S2 to release the load 4 from the delivery shaft 3, by means of the pressure P in the delivery shaft 3, above the stealth aircraft 1.

The blocks of the block diagram in 2 The method steps illustrated can, for example, be substantially represented in a machine-, processor- or computer-readable data carrier and thus by a computer or processor 18, as described below with respect to 3 Examples may also be or refer to a computer program that includes program code for executing at least part of the method steps of 2 when the computer program is executed on the computer or processor 18. An example may also include a volatile memory 19 or persistent memory 20, as also described below with respect to 3 described, which is machine-, processor- or computer-readable and encodes machine-executable, processor-executable or computer-executable programs containing instructions that cause some or all of the method steps to be carried out.

3 shows a schematic view of the control unit 17 of the stealth aircraft 1. 3 shows schematically a block diagram illustrating the (central) control unit 17 as a computer device. The control unit 17 may, for example, be an integrated part of the stealth aircraft 1. The control unit 17 implements one or more steps of the method S0 as shown in 2 In particular, the control unit 17 provides functionality, such as computer software running on the control unit 17 and executing one or more steps of the method S0.

The data or information referred to below as compact data includes one or more of: the navigation data, pressure value to be set, measured pressure, target pressure value, flow area, or information and signal data related to the inlet, the outlet, the discharge shaft, the compressor, the magazine and/or the sabot. These elements are referred to as compact data for the sake of simplicity, even if in some places not all of the data or information described above is appropriate.

In particular, the control unit 17 may execute instructions related to the compact data that are included in the computer program described herein and cause the control unit 17 to execute or initiate the one or more steps of the method S0.

It is contemplated herein that the control unit 17 may take any suitable physical form. As an example, the control unit 17 may be embodied at least in part as an embedded computer, system-on-chip (SOC), and/or single-board computer (SBC). The control unit 17 may be uniform or distributed; span one or more locations in the stealth aircraft 1; or span one or more machines therein. The control unit 17 may execute or initiate one or more steps of the method S0 without significant spatial or temporal limitation. As an example, the control unit 17 may execute or initiate one or more steps of the method S0 in real time, in parallel, or in batch mode. The control unit 17 may execute or initiate step(s) of the method S0 at different times or at different locations.

The control unit 17 has at least one or more of the following components: the processor 18, the volatile memory 19, the permanent memory 20, a bus 21, an arbiter 22, one or more interfaces 23, a main power supply 24 and an auxiliary power supply 25. The components of the control unit 17 can be at least partially implemented in hardware and/or software. The interconnection of the components of the control unit 17 is shown as in 3 structured. In particular, the interconnection and connection can differ in implementation due to signal processing and signaling.

The processor 18 has means for executing instructions associated with the compact data, e.g. of the computer program described herein. For example, the processor 18 may load the instructions associated with the compact data contained in the computer program described herein, e.g. from the volatile memory 19 and/or the persistent memory 20 and then execute the instructions, which in turn causes the processor 18 to perform the one or more steps of the method S0, e.g. in 2 illustrated. The processor 18 may include an internal register/cache for the compact data, instructions associated with the compact data, and/or associated addresses. The processor 18 may include an FPGA, ASIC, DSP, microcontroller, CPU, and/or GPU to access the internal register/cache. As an example, to execute instructions associated with the compact data, the processor 18 may retrieve them from the processor 18's internal register/cache, volatile memory 19, or persistent memory 20; decrypt and execute them; and then write a result to the processor 18's internal register/cache, volatile memory 19, or persistent memory 20.

As an example, the processor 18 may include an instruction cache, a data cache, and/or a translation buffer (TLB). The instructions related to the compact data in the instruction cache may be copies of instructions in the volatile memory 19 and/or persistent storage 20, and the instruction cache may speed up the retrieval of these instructions related to the compact data by the processor 18. The compact data in the data cache may be copies of data for the instructions currently executing on the processor 18 and related to the compact data in the volatile memory 19 and/or persistent storage 20. The results of previous instructions executing on the processor 18 and related to the compact data may be intended for access by subsequent instructions executing on the processor 18 and related to the compact data, or for writing to the volatile memory 19 and/or persistent storage 20. The data cache may speed up the read or write operations of the processor 18. The addresses associated with the compact data in the TLB may be address references to addresses in the volatile memory 19 and/or persistent storage 20 to speed up the virtual address translation for the processor 18.

The volatile memory 19 may be a dynamic RAM (DRAM) or a static RAM (SRAM). The volatile memory 19 may in particular be embodied as the data carrier described herein on which the computer program described herein may be stored at least temporarily. In addition, the volatile memory 19 may be a single or multi-channel RAM. The volatile memory 19 may include a main memory for storing instructions related to the compact data for the processor 18, which then executes these instructions; or include the compact data for the processor 18 that the processor 18 uses to operate on it. As an example, the control unit 17 may load these instructions into the volatile memory 19 from the persistent memory 20 or another source (such as another computer, the network, or the cloud). The processor 18 may then load these instructions from the volatile memory 19 into the internal register/cache of the processor 18. To execute these instructions, the processor 18 may retrieve and decode these instructions from the appropriate internal register/cache. During or after executing these instructions, the processor 18 may write a result (which may be intermediate or final results) to the internal register/cache. The processor 18 may then write the result to the volatile memory 19.

For example, processor 18 executes only instructions related to compact data in processor 18's internal register/cache or volatile memory 19 (as opposed to persistent memory 20), and operates only on compact data in processor 18's internal register/cache or volatile memory 19 (as opposed to persistent memory 20).

The persistent memory 20 has a mass storage, e.g. a non-volatile mass storage (NVM), for the compact data or the instructions associated with the compact data. The persistent memory 20 can in particular be designed as the data carrier described herein, on which the computer program described herein can be stored. As an example, the persistent memory 20 can be a flash memory, in particular SSD or eMMC. The persistent memory 20 can store the compact data in an erasable or non-erasable manner. The persistent memory 20 can be located in the control unit 17, i.e. internally, or can be located externally thereto.

The processor 18 can be connected to the permanent memory 20 directly or indirectly, e.g. via the arbiter 22. The connection can be designed via a clock bus, command bus and data bus. This is only shown schematically using the bus 21 in 3 shown. The persistent memory 20 receives instructions associated with the compact data and the compact data in conjunction with a clock signal provided by the processor 18 on the clock bus. The clock signal clocks the reception of the instructions associated with the compact data and the compact data. The processor 18 sends an instruction associated with the compact data to the persistent memory 20 via the instruction bus. The processor 18 also sends the compact data to the persistent memory 20 via the data bus in accordance with the instruction or receives the compact data from the persistent memory 20 via the data bus.

In one example, persistent memory 20 may have a clock pin through which the clock signal is received at persistent memory 20. The clock signal may be a write enable signal and/or a read enable signal. Persistent memory 20 may further have first and second input/output (I/O) pins. The compact data is received at persistent memory 20 in synchronism with the clock signal through the first I/O pin. Persistent memory 20 may further have a command/address buffer, control logic, and an I/O buffer. The command/address buffer operates at a first operating speed and buffers the command and corresponding address associated with the compact data received through the second I/O pin in synchronism with the clock signal. The an I/O buffer operates at the first operating speed and buffers the compact data as read data from the NVM or writes the compact data as write data to the NVM. The first and second I/O pins may coincide. Here, the clock signal may be formed by a first and second clock signal, in which the first clock signal only switches during a period in which the command and the address (both related to the compact data) are received from persistent memory 20, and the second clock signal only switches during a period in which the compact data is received from persistent memory 20. The first operating speed corresponds to a data input speed or data output speed between persistent memory 20 and processor 18. The control logic controls an operation with respect to the NVM based on the buffered command and the buffered address (both related to the compact data). Here, the control logic operates at a second operating speed that is lower than the first operating speed and corresponds to an internal operating speed of persistent memory 20.

The bus 21 can be understood here as a subsystem of the control unit 17 that transmits the compact data and/or electrical power between the components of the control unit 17. The (one) bus 21 can connect the components of the control unit 17 to one another via the same set of lines. The bus 21 can be designed for dedicated communication of the compact data between two or more of the components of the control unit 17. The bus 21 can be a system bus via which the processor 18 is connected to the other components of the control unit 17. In this case, the bus 21 can be synchronous - the compact data is accepted bidirectionally with a clock edge of a clocking of the bus 21 - and/or asynchronous - no clocking, but a handshake is carried out to accept the compact data. In such a semi-synchronous system bus, the bus 21 is clocked, but control lines enable wait cycles in order to also use slow components, such as the permanent memory 20, via the bus 21.

The arbiter 22 can be provided for at least partial control over the bus 21. The arbiter 22 can be understood as a coprocessor that is subordinate to the processor 18. The arbiter 22 regulates the access to the bus 21 related to the compact data based on a two-way handshake or three-way handshake. The three signals bus request (BREQ) for forwarding the compact data, bus grant (BGRT) for confirming and approving forwarding and bus grant acknowledge (BGA) for optional forwarding feedback are used for this purpose. The arbiter 22 simultaneously receives several BREQs from different components of the control unit 17 via the bus 21. The arbiter 22 sorts the BREQs according to priority and forwards them sequentially - in a pipeline - to the processor 18. As soon as the processor 18 has received the BREQ, the processor 18 sends the BGRT to the arbiter 22 or directly to the component of the control unit 17 that sent the BREQ. A subordinate BREQ of the BREQs in the pipeline - e.g. from another component of the control unit 17 - is forwarded to the processor 18 in response to a BGRT sent by the processor 18 relating to the BREQ that has priority in the pipeline and is related to at least part of the compact data. The BGRT relating to the subordinate BREQ is sent by the processor 18 to the arbiter 22 after at least part of the compact data has been processed. The arbiter 22 can, for example, in turn send a BREQ of the BREQs that is further subordinate in the pipeline - e.g. relating to another part of the compact data - to the processor 18 in response to the BGRT relating to the subordinate BREQ. Likewise, in response to each BGRT from the processor 18, the arbiter 22 can send a respective BGA related thereto to the processor 18. With the procedure described here, a BGA can also be omitted entirely. This saves overhead in the communication between the components of the control unit 17. That is, a two-way handshake is provided instead of a three-way handshake.

The bus 21 can also have a data bus, address bus and control bus. In this case, the compact data is transmitted bidirectionally between the components of the control unit 17 via the data bus. The address bus is operated solely by the processor 18 and unidirectionally transmits memory addresses associated with the compact data. The control bus is regulated solely by the arbiter 22, e.g. in the sense of a watchdog, and passes control of it to the processor in the pipeline-like manner as described above in order to control the transmission of the compact data.

The interface(s) 23 enable the control unit 17 to communicate with one or more GNSS receivers (not shown). Direct wired communication connection(s) with the one or more GNSS receivers can be established via the interface(s) 23. For example, it can be an ad hoc network or local area network (LAN) consisting of the control unit 17 and the one or more GNSS receivers.

The interface(s) 23 enable the control unit 17 to communicate with a Network, e.g. Bluetooth, WLAN, mobile radio system and/or at least part of the Internet, when the stealth aircraft 1 has contact with the ground. If contact with the ground is lost, the control unit 17 can prevent communication and/or powering of wireless interface(s), except for the GNSS receivers.

The interface(s) 23 can enable user interaction with the control unit 17 in an environment of the control unit 17 (for example, on-board computers in the environment or within the aircraft cockpit). The interface(s) 23 can have device and/or software drivers that enable the processor 18 to control the interface(s) 23 in order to communicate an action instruction based on the compact data to the aircraft cockpit, in particular to the pilot, or to a general control system for controlling the stealth aircraft 1.

The interface(s) 23 can ensure a power supply to the components of the stealth aircraft 1 by means of the main power supply 24 and the auxiliary power supply 25.

The interface(s) 23 may enable sensor measurements in a close vicinity of the control unit 17. The interface(s) 23 may be connected to the external air pressure sensor 14, which couples to the processor 18 of the control unit 17. The interface(s) 23 may include device and/or software drivers that enable the processor 18 to control the interface(s) 23 to obtain measurements from the air pressure sensor 14 on which the compact data is based or which are represented by the compact data.

The control unit 17 as a (NR) UE can be used in narrow band (NB) Internet of Things (IoT) applications in which only occasional and small amounts of data are sent in the uplink (UL), such as the compact data. This can happen immediately when the stealth aircraft 1 takes off. For example, the control unit 17 can be part of a 4-stage Random Access Channel (RACH) transmission procedure that includes the transmission of four messages (Msg1, Msg2, Msg3 and Msg4) before the transmission of the compact data to the serving base station. Here, the control unit 17 can perform a random access by sending a RACH preamble - e.g. Msg1 - on a RACH resource. The serving base station can respond with a Random Access Response (RAR) - e.g. Msg2. The control unit 17 can then send a Radio Resource Control (RRC) connection request - e.g. Msg3 - in the Physical Uplink Shared Channel (PUSCH) (e.g. NR-PUSCH). The serving base station can then respond with a RRC Connection Setup - e.g. Msg4 - which completes the initial access process of the control unit 17. This RACH mode is an inefficient way of transmitting the compact data, since a transmission of the compact data between the control unit 17 and the serving base station only takes place after the four messages.

The control unit 17 can also send the compact data via the communication interface 23 at a predefined event. This predefined event can be the completion of the successful establishment of a communication connection with a network. In this case, the control unit 17 can retrieve the compact data located in the volatile memory 19 and forward it in packets via the communication interface 23 via the mobile radio system.

The main power supply 24 supplies at least one or more of the components of the control unit 17 and the stealth aircraft 1 with electrical power, e.g. via the bus 21 and the interface(s) 23. In particular, the main power supply 24 charges the auxiliary power supply 25 with electrical power, e.g. from outside the control unit 17, e.g. in case the main power supply 24 is connected to the power source outside the control unit 17. Here, the main power supply 24 can represent a preferred component used for the power supply of the components of the control unit 17 and can comprise, for example, an accumulator or a battery. The main power supply 24 can comprise further components such as voltage regulators, DC voltage stabilizers, series regulators, buck converters and/or boost converters in order to meet the corresponding requirements of the components of the control unit 17. Here, the main power supply 24 can have either a dedicated fixed power supply connection to the external power source or a detachable power supply connection for charging the accumulator or the battery of the main power supply 24. For this purpose, the main power supply 24 can have an inverter to provide a predetermined DC power supply from a connected AC power source as the external power source. The predetermined DC power supply can also already be provided by a connected DC power source as the external power source. The DC power supply can be regulated via the above-mentioned voltage regulators and supplied to the components controlled by the control unit 17 and the other components of the stealth aircraft 1 as set DC power supplies.

The auxiliary power supply 25 is connected to the volatile memory 19 and/or the permanent memory 20 via the bus 21. The auxiliary power supply 25 is charged by the electrical power of the main power supply 24. The auxiliary power supply 25 can be arranged inside or outside the control unit 17, or inside or outside the volatile memory 19 and/or the permanent memory 20. For example, the auxiliary power supply 25 can be accommodated on a main board of the control unit 17 in order to supply the volatile memory 19 and/or the permanent memory 20 with an auxiliary power. The auxiliary power supply 25 can in particular be designed in the form of a supercapacitor, an accumulator and/or a battery. The power capacity/energy capacity of the main power supply 24 can be many times, for example at least 10 times or 50 times greater than the power capacity/energy capacity of the auxiliary power supply 25.

The processor 18 monitors changes in the electrical power supplied by the main power supply 24. In the event of a sudden power failure, e.g., when the power source external to the control unit 17 is disconnected from the main power supply 24 or the main power supply 24 otherwise degrades or fails, and the processor 18 determines that the electrical power supplied by the main power supply 24 to one or more of the components of the control unit 17 has fallen below a threshold, e.g., 0.8 or 0.75 of an operating power of the main power supply 24, the processor 18 causes the auxiliary power supply 25 to take over a remaining supply power for a shutdown of the control unit 17. The shutdown includes powering at least the processor 18, the volatile memory 19, and/or the persistent memory 20 with electrical power for the time of the shutdown. During the shutdown process, the compact data currently located in the volatile memory 19 and/or the compact data currently being processed in the processor 18 are directly erased, for example by quickly and completely discharging the supercapacitor.

At this point, it should be noted that all parts described above, viewed individually and in any combination, in particular the details shown in the drawings, are claimed as essential to the invention. Modifications to this are familiar to the person skilled in the art.

REFERENCE SYMBOL LIST

1

stealth aircraft

2

airframe

3

delivery shaft

4

load

5

sabot

6

outlet

7

exhaust flap

8

exhaust channel

9

inlet

10

intake flap

11

intake channel

12

tailgate(s)

13

magazine

14

air pressure sensor

15

compressor device

16

compressed air duct

17

control unit

18

processor

19

Volatile memory

20

permanent storage

21

bus

22

arbitrator

23

interface(s)

24

main power supply

25

auxiliary power supply

A

front top

B

rear top

C

bottom

F

direction of flight

P

Pressure

Claims (10)

Stealth aircraft (1) with an aerodynamic and stealth-optimized airframe (2), the stealth aircraft (1) comprising: a discharge shaft (3) which is arranged in the airframe (2) in order to prepare a dropping of a load (4) to be dropped from the stealth aircraft (1) during flight of the stealth aircraft (1); an outlet (6) which connects the discharge shaft (3) to a rear upper side (B) of the airframe (2); a control unit (17) which is designed to control the outlet (6) in order to drop the load (4) from the discharge shaft (3) via the outlet (6); and characterized in that the outlet (6) is arranged on the airframe (2). is to drop the load (4) over a side of the stealth aircraft (1) facing away from the earth's surface. stealth aircraft (1) to claim 1 , characterized in that the stealth aircraft (1) further comprises an inlet (9) which connects the discharge duct (3) to a forward upper side (A) of the airframe (2); and the inlet (9) on the airframe (2) is arranged and designed such that an air flow into the discharge duct (3) caused by the flight operation of the stealth aircraft (1), from the front in the direction of flight (F), provides a pressure (P) which causes the load (4) to be pushed rearward in the direction of flight (F) through the outlet (6) in order to jettison the load (4) over the upper side (B) of the airframe (2). stealth aircraft (1) to claim 2 , characterized in that the inlet (9) has an inlet flap (10) which is designed to be operated in two operating positions, OPEN and CLOSED; the outlet (6) has an outlet flap (7) which is designed to be operated in the two operating positions, OPEN and CLOSED; the inlet (9) further has an inlet duct (11) which provides a direct air supply connection from the inlet flap (10) to the discharge duct (3); and the outlet (6) further has an outlet duct (8) which provides a direct air discharge connection from the discharge duct (3) to the outlet flap (7). stealth aircraft (1) to claim 3 , characterized in that the inlet flap (10) and the outlet flap (7) are each aligned in the CLOSED operating position with the upper side (A, B) of the aircraft frame (2), which is preferably an airframe or fuselage. stealth aircraft (1) to claim 3 or 4 , characterized in that the stealth aircraft (1) further comprises one or more aircraft engines for propelling the stealth aircraft (1) in the air; and the exhaust flap (7) and the one or more aircraft engines are arranged relative to one another on the airframe (2) so that the load (4) remains unaffected by exhaust gases from the aircraft engine. Stealth aircraft (1) after one of the Claims 3 until 5 , characterized in that the control unit (17) is designed to control the inlet (9) and the outlet (6) during flight operation of the stealth aircraft (1) for load shedding such that the outlet flap (7) and the inlet flap (10) are simultaneously in the OPEN operating position in order to jettison the load (4) from the discharge shaft (3) on the upper side (B) of the stealth aircraft (1) by means of an air flow through the inlet channel (11) caused by the flight operation in the direction from the inlet (9) to the outlet (6). Stealth aircraft (1) after one of the Claims 2 until 6 , characterized in that a) the pressure (P) is designed taking into account a sabot (5) attached to the load (4), and/or b) the stealth aircraft (1) further comprises: an air pressure sensor (14) which is designed to measure the pressure (P) provided by the air flow into the discharge shaft (3); a compressor device (15) which is designed to generate compressed air; and a compressed air channel (16) which is arranged between the compressor device (15) and the discharge shaft (3) to discharge the generated compressed air into the discharge shaft (3) and to supply the discharge shaft (3) with the compressed air; and the control unit (17) is further designed to set a pressure value of the compressor device (15) based on a difference between a target pressure value of the discharge shaft (3) and the measured pressure (P) of the discharge shaft (3), and the compressor device (15) is designed to generate the compressed air with the set pressure value. Stealth aircraft (1) according to one of the preceding claims, characterized in that the stealth aircraft (1) further comprises a cargo hold with one or more loading flaps (12) arranged on an underside (C) of the airframe (2), which extend along a longitudinal axis of the stealth aircraft (1) and via which the load (4) to be dropped is to be loaded into the stealth aircraft (1); the stealth aircraft (1) further comprises a magazine (13) which is designed to store the load (4) to be dropped rotatably or linearly between the cargo hold in which the load (4) is to be loaded and the discharge shaft (3) from which the load (4) is to be released to the outlet (6); and the control unit (17) is designed to keep the one or more loading flaps (12) of the cargo hold closed during flight operations. Method (S0) for operating a stealth aircraft (1) having an airframe (2) with an aerodynamic design and an integrated discharge shaft (3), and a control unit (17), the method (S0) comprising: providing (S1), by means of a magazine (13), a load (4) to be dropped in the discharge shaft (3), as long as navigation data provided to the control unit (17) do not indicate a target area for dropping the load (4); and actuation (S2), by the control unit (17), of an outlet (6), as soon as the navigation data indicate the target area for dropping the load (4), in order to drop the load (4) from the discharge chute (3), by means of a pressure (P) in the discharge chute (3), over a side of the stealth aircraft (1) facing away from the earth's surface. Computer program comprising instructions which, when the computer program is executed by a computer, cause the computer to carry out the method (S0) according to claim 9 or to execute or initiate steps (S1, S2) thereof.

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