Abstract: Information, an alert or an alarm is supplied to an aircraft in proximity to the ground. A grid of geographic coordinates is established, each mesh of which exhibits a defined relief. The trajectory of the aircraft is predicted over a predetermined time interval. An intersection, if any, between the predicted trajectory and the relief of at least one of the meshes is determined. An alert or alarm is activated in the case of such an intersection. The alert or alarm is inhibited when the aircraft is in landing configuration or when the runway is detected and a series of conditions relating to landing are fulfilled.

Abstract: A process and a device for detecting inconsistencies in the operation of a system with multiple phases of operation, controlled by at least one operator. The current phase of operation of the system is determined. For the determined phase, reference is made to at least one theoretical model representative of at least one feature of the system. The effective values of the variables used in the theoretical model is detected. The detected effective values are compared to theoretical data defined in the theoretical model. Any incompatibility detected during these comparisons is signaled together with the nature of this incompatibility. The detection system can be used with the pilotage of aircraft.

Abstract: System for deriving an information, warning or alarm signal on board an aircraft in the event of an anomaly during take-off.According to the invention, the system comprises:means (4) for calculating the position D.sub.stop on the runway where the aircraft must stop if the pilot decides to interrupt the take-off procedure immediately, that is to say representative of the stopping distance of the aircraft during the acceleration phase of the latter at take-off; means (5) for comparing D.sub.stop to the length of runway L available so as to determine whether an interruption of the take-off is still possible.

Abstract: The present invention relates to a device for supervising the propulsion system of an aircraft, including a set of sensors (C1, C2, Cn) delivering information regarding the propulsion system. According to the invention, the device moreover includes:a set of peripheral computers (M1, M2, Mp) each implementing a mathematical model representing a sub-system of propulsion system; anda main computer (CAL), which is linked to the set of sensors (C1, C2, Cn) and to the set of peripheral computers (M1, M2, Mp), which checks the intercompatibility of the information delivered by the sensors (C1, C2, Cn) and the compatibility between the information delivered and the results provided by the peripheral computers (M1, M2, Mp).

Abstract: A process and device for detecting the current phase of operation of a system with multiple phases of operation. According to the invention, the operation is partitioned into a set of phases (I to X) from which is chosen a reference phase (I). The set of possible switches to the other phases is determined for each phase. And, a set of parameters is defined for each of the switches, the set of parameters being characteristic of the switch. The sets of parameters are continuously detected. The chain of switches actually involved is determined on the basis of the reference phase (I) with the aid of variations in the parameters, and the current phase of operation is deduced from the chain of switches. Although the invention is applicable to numerous systems, one such system to which it is applicable is the operation of a transport airplane.