Abstract: A method for diagnosis of a loss of control of an aircraft comprises the steps: loading raw data; loading parameters of the aircraft; computing a plurality of reference data comprising a preprocessing comprising for at least one reference datum a sub-step of computing a phase advance term; determining the characteristic thresholds indicative of loss of control; detecting at least one type of loss of control by comparing the reference data with characteristic thresholds; and, when at least one type of loss of control is detected: identifying the type of priority loss of control corresponding to the type of loss of control exhibiting the highest priority level, and communicating the type of priority loss of control to a crew.

Abstract: A method for automatic yaw axis control in aircraft with mechanical controls, said aircraft including a yaw actuator to control orientation of a yaw control surface and deliver a measured value of the torque on the control surface, a yaw trim actuator driving movement of a yaw trim control surface limiting the force applied by the yaw actuator to orient the yaw control surface, and sensors supplying an estimate of a lateral yaw force, includes calculating a setpoint value for the position of the yaw control surface determined by the estimated lateral force, an estimated torque of the yaw actuator determined by the measured value of the torque of the yaw actuator and a measured position of the yaw control surface, the estimated torque calculated having a lower oscillation dynamic range than the measured torque, and a trim command for activating/deactivating the yaw trim actuator determined by the estimated torque.

Abstract: A method for automatic yaw axis control in aircraft with mechanical controls, said aircraft including a yaw actuator to control orientation of a yaw control surface and deliver a measured value of the torque on the control surface, a yaw trim actuator driving movement of a yaw trim control surface limiting the force applied by the yaw actuator to orient the yaw control surface, and sensors supplying an estimate of a lateral yaw force, includes calculating a setpoint value for the position of the yaw control surface determined by the estimated lateral force, an estimated torque of the yaw actuator determined by the measured value of the torque of the yaw actuator and a measured position of the yaw control surface, the estimated torque calculated having a lower oscillation dynamic range than the measured torque, and a trim command for activating/deactivating the yaw trim actuator determined by the estimated torque.

Abstract: A secure conversion device for an aircraft equipped with a digital computer and an analog actuator, said device being capable of converting discrete digital controls provided by the computer into analog power signals transmitted to the analog actuator and making it possible to steer said actuator, comprises a security module, making it possible to identify inconsistencies in the discrete digital controls and to interrupt the transmission of the analog power signals toward the analog actuator when an inconsistency in the discrete digital controls is identified. The device also comprises a detection module, making it possible to determine power levels of the analog power signals. The device also comprises a monitoring module, making it possible to detect anomalies in power supply levels of components of the device.

Abstract: The invention relates to automatic pilot devices on board aircraft, and more particularly aircraft of the maritime patrol or surveillance type. The invention is a device able to be engaged instinctively, calculating at least two flight path modes, the first one being a horizontal circular flight path around a location point and the second one being the overflying of a location point according to a heading chosen on a horizontal line, and making it possible to direct the aircraft automatically according to these two flight paths.