Abstract: A system implementing a method for generating a navigation output is provided. The method includes determining a gravitational anomaly estimate based at least in part on inertial sensor data and navigation output; generating navigation and sensor corrections that are due at least in part on inherent sensor errors that include vertical accelerometer/gravimeter corrections from at least a navigation output estimate, the gravitational anomaly estimate, and the gravity map data; and generating the navigation output based on the inertial sensor data, gravity map data and the navigation and sensor corrections.

Abstract: Physical and logical components of a long line loiter control system address control of a long line loiter maneuver conducted beneath a carrier, such as a fixed-wing aircraft. Control may comprise identifying, predicting, and reacting to estimated states and predicted states of the carrier, a suspended load control system, and a long line. Identifying, predicting, and reacting to estimated states and predicted states may comprise determining characteristics of state conditions over time as well as response time between state conditions. Reacting may comprise controlling a hoist of the carrier, controlling thrusters of the suspended load control system, and or controlling or issuing flight control instructions to the carrier so as not to increase the response time and or to avoid a hazard.

Abstract: In an embodiment, a method includes: obtaining a first signal from a first sensor of a rotorcraft, the first signal indicating measured angular velocity around a first axis of the rotorcraft; filtering the first signal with a lag compensator to estimate angular position around the first axis of the rotorcraft; and adjusting flight control devices of the rotorcraft according to the estimated angular position and the measured angular velocity around the first axis of the rotorcraft, thereby changing flight characteristics of the rotorcraft around the first axis of the rotorcraft.

Abstract: An attitude measurement method, which relates to the technical field of measurement while drilling in directional drilling, which can improve the observability of inertial instrument errors, suppress the repeatability errors of gyroscopes and improve the attitude measurement accuracy.

Abstract: A transportation system that includes one or more pods that each includes an interior space configured to house travelers and objects. The pods can be attached to and transported by multiple different vehicles. The different vehicles can provide for different modes of transportation depending upon the plans of the travelers. Different modes include but are not limited to ground travel, air travel, water travel, and rail travel.

Abstract: A system for flight control in electric aircraft includes a flight controller configured to provide an initial vehicle torque signal including a plurality of attitude commands. The system includes a mixer configured to receive the initial vehicle torque signal and a vehicle torque limit, receive prioritization data including a prioritization datum corresponding to each of the plurality of attitude command, determine a plurality of modified attitude commands as a function of the vehicle torque limit, the attitude commands, and the prioritization data, generate, as a function of modified attitude commands, an output torque command including the initial vehicle torque signal adjusted as a function of the vehicle torque limit, generate, as a function of the output torque command, a remaining vehicle torque. The system includes a display, wherein the display is configured to present, to a user, the remaining vehicle torque and the output torque command.

Abstract: A system includes an air data computer (ADC) having a single pneumatic port for receiving a pneumatic input, a plurality of electrical inputs for receiving one or more electrical signals, and an output. The ADC can transmit, via the output, air data parameters based on the received pneumatic input and the received one or more electrical signals. In a further example embodiment, the system includes a first pressure sensing probe discrete from the ADC and a pneumatic connection joining a pressure sensing port of the first probe to the pneumatic input of the ADC. Second and third pressure sensing probes pneumatically coupled to respective pressure modules, which output electrical signals to the ADC, the electrical signals being representative of pressures sensed by the second and third pressure sensing probes, respectively.

Abstract: A computer-implemented method in an aircraft for identifying a flight plan modification that has a favorable impact from jet streams is provided. The method includes: retrieving an entered flight plan for the aircraft; retrieving available jet stream data identifying one or more jet streams in proximity to a proposed flight path from the entered flight plan, wherein the jet stream data includes jet stream vector, altitude, width, and thickness data; projecting the jet stream data around the proposed flight path as points of interest around the proposed flight path; identifying a flight plan modification that has the most favorable impact from jet streams at the points of interest; and displaying the identified flight plan modification on a user interface.

Abstract: A method for providing a steering recommendation for a vehicle for negotiating an obstacle includes receiving terrain information, the terrain information indicative of a surface of an obstacle, the surface facing an approaching wheel of the vehicle. The method further includes determining, from the terrain information, at least one characteristic of the facing surface of the obstacle and determining, in dependence on the determined at least one characteristic, a steering recommendation for the wheel to negotiate the obstacle. The method further includes providing the steering recommendation for use in negotiating the obstacle. A computer-readable medium, a controller, a system and a vehicle are also provided.

Abstract: An autopilot recoupling system for a rotorcraft having an automatic flight control system with multiple layers of flight augmentation. The autopilot recoupling system includes an autopilot recoupling input operable to generate an autopilot recoupling signal. An autopilot recoupling signal processor is communicably coupled to the autopilot recoupling input. The autopilot recoupling signal processor is configured to receive the autopilot recoupling signal from the autopilot recoupling input and responsive thereto, determine a state of the automatic flight control system, activate a trim systems layer of the automatic flight control system if the trim systems layer is not active, engage an attitude retention systems layer of the automatic flight control system if the attitude retention systems layer is disengaged and recouple an autopilot systems layer of the automatic flight control system.

Abstract: An inertial measurement system for aircraft, the system comprising at least one processor unit connected to at least two inertial units, namely at least one inertial unit of a first type having at least three angular sensors and three linear sensors aligned on three substantially distinct sensing axes, and an inertial unit of a second type comprising at least four angular sensors and four linear sensors aligned on four substantially distinct sensing axes. The system is arranged to calculate one piece of inertial data from the six sensors of the inertial unit of the first type and four pieces of inertial data from four distinct combinations of three angular sensors and three linear sensors selected from the sensors of the inertial unit of the second type, and the processor unit is arranged to compare the four pieces of inertial data from the measurements of the inertial unit of the second type with one another so as to determine whether the inertial unit of the second type has failed.

Abstract: A printer deposits material onto a substrate as part of a manufacturing process for an electronic product. At least one mechanical component experiences mechanical error, which is mitigated using transducers that equalize position of a transported thing, e.g., to provide an “ideal” conveyance path; a substrate conveyance system and/or a printhead conveyance system can each use transducers in this manner to improve precise droplet placement. In one embodiment, errors are measured in advance, with corrections being “played back” during production runs to mitigate repeatable transport path error. In a still more detailed embodiment, the transducers can be predicated on voice coils, which cooperate with a floatation table and floating, mechanical pivot assembly to provide frictionless, but mechanically-supported error correction.

Abstract: An inexpensive stall warning device for the instrument panel of an airplane or glider operates on the principle of balancing dynamic pressure against normal acceleration forces. It requires only static and pitot pressure inputs and electric power and employs a differential pressure transducer, MEMS rate gyros and accelerometers. These sensors will be monitored by a microprocessor to derive the aerodynamic states of the aircraft, thereupon issuing explicit display and vocal announcements to a pilot to prevent or guide recovery from a stall or spin state as well as overspeed or spiral dive.

Abstract: Method and apparatus of integrating a three-axis magnetometer and a three-axis accelerometer to provide attitude and heading, calibrated magnetometer and accelerometer data, and angular rate, while removing sensor error sources over time and temperature and to compensate for hard and soft iron distortions of the Earth magnetic field. Filtered accelerometer data are corrected to account for various error sources. The magnetic heading is calculated from a horizontal magnetic field vector transformed from three dimensional Earth's magnetic field vector by using quasi-static roll and pitch angles from the filtered accelerometer data. A first Kalman filter estimates the state vector, based on the principle that the magnitude of local Earth's magnetic field vector is constant, to form hard and soft iron correction matrices.

Abstract: Reducing noise from drive tone and sense resonance peaks of a micro-electro-mechanical system (MEMS) gyroscope output using a notch filter is presented herein. The MEMS gyroscope can include a drive oscillation component configured to vibrate a sensor mass at a drive resonance frequency; a sense circuit configured to detect a deflection of the sensor mass, and generate, based on the deflection and the drive resonance frequency, a demodulated output; and a signal processing component configured to receive a set of frequencies comprising a first value representing the drive resonance frequency and a second value corresponding to a sense resonance frequency associated with the sense circuit, and apply, based on the first value and the second value, a notch filter to the demodulated output to obtain a filtered output.

Abstract: A reduced-order fail-safe inertial measurement unit system. A first inertial measurement unit device includes a plurality of accelerometers measuring linear accelerations and gyroscopes measuring angular velocities. A second inertial measurement unit device includes a reduced number of accelerometers and gyroscopes relative to the first inertial measurement unit device measuring at least two linear accelerations and at least one angular velocity. A processor receives acceleration data from the first and second inertial measurement units. The processor detects faulty data measurements from the first inertial measurement unit. The processor supplements the faulty data measurements of the first inertial measurement unit with transformed data generated as a function of the measurement data from the second inertial measurement unit. The processor applies predetermined transformation solutions to transform the measurement data from the second inertial measurement unit into the transformed data.

Abstract: Systems and methods are provided for a roll attitude dependent roll rate limit that may limit an aircraft to a lower roll rate limit under normal flight conditions. The systems and methods may detect situations where a higher roll rate limit may be desirable and allow the aircraft to exceed the lower roll rate limit, to either a higher roll rate limit or a roll rate between the lower and higher roll rate limit.

Abstract: Systems and methods for off-line and on-line sensor calibration are provided. In certain embodiments, a method for calibrating a sensor comprises receiving at least one reference measurement describing a system state for a system; and receiving at least one sensor measurement from the sensor, wherein the at least one sensor measurement is acquired from an observation of the environment of the system by the sensor. The method also comprises calculating a model residual power spectral density based on the at least one reference measurement and a sensor measurement model; and calculating a measurement residual power spectral density based on the at least one sensor measurement and the at least one reference measurement. Further, the method comprises identifying sensor parameters that morph the model residual power spectral density towards the measurement residual power spectral density.

Abstract: Systems and methods for navigation of a vehicle may carry out one or more operations including, but not limited to: obtaining coordinates of a vector connecting two points in space using carrier phase measurements from global navigation system satellites (GNSS); setting the vector as an intended path of a vehicle; storing carrier phase signals from a GNSS receiver received at a first position of the vehicle; receiving carrier phase signals from a GNSS receiver at a second position of the vehicle; and determining a position of the vehicle relative to the intended path from one or more carrier phase signals received at the second position and one or more stored carrier phase signals received at the first position.

Abstract: A method and apparatus process a signal include local clock signal generators configured to, based on a reference clock signal, generate operation clock signals for analog channels and, based on a synchronizing signal, adjust a phase difference among the operation clock signals.

Abstract: A method of dynamically alleviating loads generated on an aircraft by a disturbance of gust and/or turbulence. The method comprises monitoring, during flight of the aircraft, to automatically detect a disturbance due to gust and/or turbulence and determining an incidence angle or angle of attack of the disturbance. When a disturbance due to gust and/or turbulence is detected, automatically generating control commands for deflecting control surfaces dependent on the incidence angle or angle of attack, and applying the control commands to deflect the control surfaces.

Abstract: A system and method for mounting a device to a piece of equipment is presented, and may include a handheld inertial measurement unit (IMU), a computer logic and a mounting interface. The piece of equipment may have a line replaceable unit (LRU) mount that allows a new LRU to be mounted thereon. The mounting interface may be mounted to a LRU mount. The handheld IMU may determine position data with respect to the LRU mount and the piece of equipment. The computer logic may be configured to calculate a positional error value based on the position data to indicate to a user whether corrections need to be made regarding how the new LRU is mounted to the LRU mount before the new LRU is mounted to the LRU mount or whether the new LRU can be mounted to the LRU mount without any corrections.

Abstract: Systems, methods, and devices are provided for assisted takeoff of an aerial vehicle. The aerial vehicle may takeoff using a first control scheme and switch to a second control scheme for normal flight when a takeoff threshold is met. The first control scheme optionally does not use integral control while the second control scheme may use integral control. The aerial vehicle may determine that a takeoff threshold is met, based on an output to a motor of the aerial vehicle and/or an acceleration of the aerial vehicle.

Abstract: A method for simulating the movement behavior of a fluid in a closed moving container is provided. The simulation is based on the determination of the potential movement path of the center of gravity of the volume of the fluid as an elliptical trajectory situated in a disturbance plane having certain semi-axes.

Abstract: A method for attenuating effects of turbulence on an aircraft, and a device to implement the method, the method including: using at least one signal on a wind profile signal, along an excitation direction, representing, at a given moment in an aircraft referential, a component along the excitation direction of the wind speed at a front of the aircraft according to a distance along a longitudinal direction of the aircraft; carrying out a frequency determination, in which the wind profile signal is processed to determine a frequential content; and selecting a control strategy to be adopted according to the previously determined frequential content, the strategy enabling at least one applicable control law to be identified.

Abstract: Methods and apparatus for driving rotational elements of a vehicle are provided. The apparatus includes a first driving member configured to rotate a first rotational element of the vehicle relative to a body of the vehicle. The apparatus also includes a second driving member. The second driving member includes a drive structure rotatably coupled to the body. The second driving member also includes a gimbal element coupled to the drive structure via a first joint pin. The gimbal element is configured to couple to a second rotational element of the vehicle such that when the drive structure is rotated relative to the body, the second rotational element rotates relative to the first rotational element. The gimbal element is configured to pivot about the first joint pin relative to the drive structure based on the rotation of the first rotational element and the rotation of the second rotational element.

Abstract: A system and method for steering aircraft along a predetermined track is disclosed herein. The system and method relate to steering an aircraft along a lateral path (e.g. a track described by reference to latitude and longitude) by a method comprising: calculating a nominal track correction; providing an upper limit and a lower limit for the nominal track correction; setting a desired track correction as: (i) the nominal track correction if the nominal track is between the upper limit and the lower limit; (ii) the upper limit if the nominal track correction is greater than or equal to the upper limit; or (iii) the lower limit if the nominal track correction is less than or equal to the lower limit; and steering the aircraft using the desired track correction.

Abstract: Disclosed is a method and device for attenuating lateral effects on an aircraft due to turbulence encountered by the aircraft during flight. The lateral effects are attenuated by applying a roll control order to control a first controllable movable member that acts on aircraft roll and minimizes aircraft roll-wise disturbances due to wind, and a yaw control order that controls a second controllable movable member to act on aircraft yaw. The roll and yaw control orders are calculated based on a sideslip value of the aircraft, while the yaw control order is calculated as a function of the roll control order to compensate for aircraft lateral effects due to turbulence, as well as lateral effects due to application of the roll control order to the first movable member.

Abstract: The fuzzy logic-based control method for helicopters carrying suspended loads utilizes a controller based on fuzzy logic membership distributions of sets of load swing angles. The anti-swing controller is fuzzy-based and has controller outputs that include additional displacements added to the helicopter trajectory in the longitudinal and lateral directions. This simple implementation requires only a small modification to the software of the helicopter position controller. The membership functions govern control parameters that are optimized using a particle swarm algorithm. The rules of the anti-swing controller are derived to mimic the performance of a time-delayed feedback controller. A tracking controller stabilizes the helicopter and tracks the trajectory generated by the anti-swing controller.

Abstract: A device comprises means for computing the air-craft (A) current position, means for determining at least one maximum permitted deviation (E1) around a set position of the flight path of the flight plan according to accuracy and integrity performances of said current position computation and to the restriction of a flight range authorized in a flight corridor (6A, 6B), and a display system (7) for displaying at least one a distance scale (9) on a viewing screen (8), at least one a fixed symbol (10) displaying the current position and two movable pointers (13, 14) displaying the limits of said maximum permitted deviation (E1).

Abstract: A hybrid helicopter includes an airframe provided with a fuselage and a lift-producing surface together with stabilizer surfaces and a drive system including: a mechanical interconnection system between a rotor of radius (R) with collective pitch and cyclic pitch control of the blades of the rotor and at least one propeller with collective pitch control of the blades of the propeller; and at least one turbine engine driving the mechanical interconnection system. The hybrid helicopter includes first members for controlling the angle at which the at least one pitch control surface is set as a function of the bending moment exerted on the rotor mast relative to the pitch axis of the hybrid helicopter, and second members for controlling the cyclic pitch of the blades of the rotor in order to control the longitudinal trim of the hybrid helicopter as a function of flight conditions.

Abstract: The device for flying an aircraft includes a first unit for determining a control value corresponding to an instruction value representing the actuation of a control member by a pilot, a second unit for determining an effective control value corresponding to the instruction value which is actually applied to the aircraft, a third unit for automatically controlling the aircraft, a fourth unit for computing an auxiliary control value, which is closer to the effective controlled value, and a fifth unit for monitoring the control value and for detecting a pilot induced oscillation, where the automatic control is carried out with the aid of the controlled effective value and the auxiliary control value in the case of the detection of the pilot induced oscillation.

Abstract: The invention relates to an actuator having an (auto)synchronous rotary electric motor and a reversible speed-reducing gearbox coupled to the motor to be driven in rotation thereby An outlet shaft is coupled to the speed-reducing gearbox to be driven in rotation thereby A first angular position sensor and a control circuit are connected to the motor. The circuit delivers a motor power supply signal that varies as a function of a position setpoint signal applied to the control circuit and as a function of signals delivered by the angular position sensor. The gearbox has a plurality of speed-reducing each having a pair of gears mounted to rotate about two parallel axes of rotation.

Abstract: An unmanned aerial vehicle including a controller operating in a search mode of operation where a receiver of an acquisition sensor searches for a target and causes flight control surfaces to guide the vehicle in a downward spiral path, a terminal mode of operation where the acquisition sensor detects a target and causes flight control surfaces to direct the vehicle toward the target, and an activation mode of operation where a trigger sensor detects a target within a predetermined distance to the vehicle and the controller activates a responder.

Abstract: The subject of the disclosed embodiments is a method of optimizing stiffened panels under stress. In particular, the method makes it possible to determine the stress distribution in stiffened panels with postbuckling taken into account. The method proposed is a coupling between an overall, linear stress calculation approach, based on strength-of-materials results, and a local, nonlinear approach for the behavior of the stiffened panel. The disclosed embodiments fall within the field of aeronautical design, at the pilot study stage in the definition of a civil transport airplane of conventional architecture.

Abstract: A method of determining the integrity of a gyro in a navigation system is provided. The method includes detecting a relatively sudden change in one of a pitch, yaw and roll signal from a respective pitch, yaw and roll gyro and reviewing at least one other of the pitch, yaw and roll signals to verify the relatively sudden change.

Abstract: An autonomous control method autonomously controls a small unmanned helicopter toward target values, such as a set position and velocity, by deriving model formulas well suited for the autonomous control of small unmanned helicopters, by designing an autonomous control algorithm based on the model formulas, and by calculating the autonomous control algorithm. The autonomous control system includes sensors that detect current position, attitude angle, altitude relative to the ground, and absolute azimuth of a nose of the small unmanned helicopter; a primary computational unit that calculates optimal control reference values for driving the helicopter from a target position or velocity values; a secondary computational unit that converts data collected by the sensors and the computational results as numeric values that are output by the primary computational unit into pulse signals; a ground station host computer used as the computational unit for the autonomous control system; and so on.

Abstract: A flight instrument and associated method where vertical speed information is combined with gyro information to produce gyro enhanced vertical speed information that is displayed to a pilot. The gyro information may include a pitch rate gyro and may include an azimuth rate gyro. The pitch rate gyro and azimuth rate gyro may be combined to yield a corrected pitch rate in turns. In one embodiment, the display is an airplane symbol that moves relative to a horizon line responsive to the gyro enhanced vertical speed information. The horizon line may also tilt in response to the azimuth rate gyro.

Abstract: Vibrations due to excitation of the natural modes of an aircraft's body are suppressed by an active multi-axis modal suppression system. Dedicated sensors are positioned in the aircraft at optimal locations for sensing modal induced vibrations. The sensor produced signals are processed through control logic which, in response thereto, and in response to aircraft inertial, velocity and altitude related signals produces output control signals. The control signals effect control surface deployment creating forces to suppress the natural mode induced vibrations on multiple geometric axis's. More particularly, a symmetric and anti-symmetric control surface deployments are used on one or more geometric axis'to damp lateral, longitudinal, vertical and most importantly torsional vibrational modes.

Abstract: In a GPS-supported inertial attitude and heading reference system equipped with a Kalman correction filter and a multiple axis fiber optic gyroscope, the invention provides for only that scale factor error which is determined for the measurement axis (e.g. the vertical axis) with relatively fast motion dynamics to be used as the Kalman filter correction value for the scale factor error correction for all the measurement axes of the FOG to determine and compensate for the scale factor error caused by changes in the wavelength of a common light source. The scale factor error correction is used only with a long time constant.

Abstract: A method for recursively determining alignment of a flight vehicle during flight is provided. The method includes generating data in a reference coordinate frame and in a second coordinate frame at a plurality of points in time during the flight, recursively generating first and second matrices from the data in the reference coordinate frame and the second coordinate frame, and at each point in time, determining an alignment output based on the inverted first matrix and the second matrix.

Abstract: A system and associated method where a vertical flight dynamic sensor is stabilized using pitch rate gyro information combined with azimuth rate gyro information corrected by scaling the azimuth rate gyro information in accordance with feedback derived from the difference between the vertical flight dynamic sensor signal and the corrected vertical flight dynamic output. In one embodiment, the vertical flighy dynamic sensor may be a vertical speed sensor. In another embodiment, the vertical flight dynamic sensor may be a pitch attitude sensor derived from the difference between an inertial based acceleration signal and a velocity based acceleration signal. The velocity based acceleration signal may be based on airspeed or GPS velocity.

Abstract: Vibrations due to excitation of the natural modes of an aircraft's body are suppressed by an active multi-axis modal suppression system. Dedicated sensors are positioned in the aircraft at optimal locations for sensing modal induced vibrations. The sensor produced signals are processed through control logic which, in response thereto, and in response to aircraft inertial, velocity and altitude related signals produces output control signals. The control signals effect control surface deployment creating forces to suppress the natural mode induced vibrations on multiple geometric axis's. More particularly, symmetric and anti-symmetric control surface deployments are used on one or more geometric axis's to damp lateral, longitudinal, vertical and most importantly torsional vibrational modes.

Abstract: A method and system for processing pulse signals within an inertial device is provided. The inertial device may have inertial sensors, such as accelerometers and gyroscopes. The inertial sensors may output signals representative of a moving body's motion. The signals may require correction due to imperfections and other errors of the inertial sensors. The inertial device may receive signals from the inertial sensors and process the signals on a signal-by-signal basis so that when processing the signals, the inertial device at least recognizes which sensor output a signal and when the signal was output. The inertial device may then correlate signals that were output from the inertial sensors at selected times in order to transform the signals into a desired navigational frame of reference.

Abstract: A method and apparatus for conducting proximity operations is disclosed. The method called inverser proximity operations includes maneuvering an active vehicle into general proximity to a target vehicle, transmitting from the target vehicle to the active vehicle data representing relative position and velocity between the target vehicle and the active vehicle, and maneuvering the active vehicle in accordance with the data to effect a desired proximity operation. Another method called distributed proximity operations includes maneuvering a carrier vehicle into general proximity to a target vehicle, releasing one or more active vehicles from the carrier vehicle, transmitting from the carrier vehicle to the active vehicle(s) data representing relative position and velocity between the target vehicle and the active vehicle, and maneuvering the active vehicle(s) in accordance with the data to effect a desired proximity operation.

Abstract: The wind turbulence prediction system according to the present invention provides a measurement system, which is capable of measuring three-dimensional wind turbulence, exhibits limited aerodynamic and structural effects when mounted on an aircraft, is capable of measurement even in cases in which the velocity is equal to or less than 20 to 30 m/s, at which velocity a Pitot tube is incapable of measurement, and even in cases where the air flow direction differs greatly from the axis of aircraft body, and does not produce an error resulting from disruption of the air flow by the aircraft body itself. The wind turbulence prediction system of the present invention adopts a system that measures the speed of remote three-dimensional air flow by mounting a laser wind speed indicator utilizing the Doppler effect on an aircraft, irradiating laser light while scanning same in a cone shape, and then receiving scattered light from wind turbulence regions forward of an aircraft body in flight.

Abstract: A system for assigning maintenance tasks to crew members of a maintenance crew during a dynamically-planned maintenance check for an aircraft includes means for obtaining a dynamic maintenance flow chart detailing up-to-date scheduling data for a predetermined number of maintenance tasks, means for obtaining personnel training records for each crew member, means for determining maintenance task assignments based upon an analysis of the maintenance flow chart and the personnel training records.

Abstract: An integrated side stick controller combines air speed, turning and altitude changing rate control into one pilot input control device. Movements of the integrated side stick controller will perform manipulations on aircraft surfaces devices in order to maneuver the aircraft. For instance, fore and aft movement of the side stick will increase/decrease the air speed, left/right movements of the side stick will control the turning of the aircraft, and up/down movements of the slider on the side stick will change the ascend/descend rate of the aircraft.

Abstract: A calculation system for calculating the control signals which are designed to perform a frequency-dependent weighting of the angular velocity signals and the angular position signals. The angular velocity indicators are preferably used for stabilization in a high frequency band while the angular position indicators are suitable for stabilization in a low frequency band. A further calculation system which is designed to perform the frequency-dependent weighting such that the control signals for frequencies below a certain frequency are substantially determined by the angular position signals and the control signals for higher frequencies are substantially determined by the angular velocity signals.

Abstract: The present invention relates to a system for the yaw control of an aircraft fitted with a plurality of engines, the system (SC) comprising in particular a computation unit (16) formulating a command dr for yaw control, dr=Ka.&PHgr;c+Kb.p+Kc.&PHgr;+Kd.r+Ke.&bgr;, on the basis of the controlled roll attitude &PHgr;c, of the roll rate p, of the effective roll attitude &PHgr;, of the yaw rate r, of the sideslip &bgr; and of gains Ka, Kb, Kc, Kd and Ke which are fixed by a device (28). According to the invention, the system (SC) comprises a a device (30) for detecting any fault with an engine of the aircraft, and the device (28) is formed in such a way as to modify the values of the gains Ka, Kd and Ke relating respectively to the controlled roll attitude &PHgr;c, to the yaw rate r and to the sideslip &bgr;, upon the detection by the device (30) of a fault with an engine of the aircraft.