Abstract: A method having a step of preparing an on-board database containing various kinds of geographical data. During a step of preparing a risk database, at least one local weather risk is stored prior to flight for at least one mesh. During a weather determination step, current and/or forecast weather conditions are acquired for at least one mesh. During a processing step, at least one combined parameter is determined for at least one mesh, each value of a combined parameter being obtained by applying a logic function giving the value of the combined parameter for a mesh as a function of the geographical data and also of the weather risk and the meteorological data. During an analysis step, the presence of a potential local weather danger, at least around the aircraft, is detected in flight as a function of the combined parameter values.

Abstract: A method of determining the speed of the wind to be taken into account for determining a maximum authorized takeoff weight of an aircraft. A measured speed TASmes of the local wind is calculated from at least one current speed TASinst of the local wind and an observed speed TASobs of the local wind on the basis of weather observations and on the basis of a heading value. The measured speed TASmes is compared with the observed speed TASobs in order to determine a calculated speed TASperfo of the local wind while also making use of at least one instability criterion of the local wind as supplied by the weather observations and weather forecasts. The calculated speed TASperfo is then for taking into account in order to optimize the maximize authorized takeoff weight of the aircraft.

Abstract: A method having a step of preparing an on-board database containing various kinds of geographical data. During a step of preparing a risk database, at least one local weather risk is stored prior to flight for at least one mesh. During a weather determination step, current and/or forecast weather conditions are acquired for at least one mesh. During a processing step, at least one combined parameter is determined for at least one mesh, each value of a combined parameter being obtained by applying a logic function giving the value of the combined parameter for a mesh as a function of the geographical data and also of the weather risk and the meteorological data. During an analysis step, the presence of a potential local weather danger, at least around the aircraft, is detected in flight as a function of the combined parameter values.

Abstract: A method of determining the speed of the wind to be taken into account for determining a maximum authorized takeoff weight of an aircraft. A measured speed TASmes of the local wind is calculated from at least one current speed TASinst of the local wind and an observed speed TASobs of the local wind on the basis of weather observations and on the basis of a heading value. The measured speed TASmes is compared with the observed speed TASobs in order to determine a calculated speed TASperfo of the local wind while also making use of at least one instability criterion of the local wind as supplied by the weather observations and weather forecasts. The calculated speed TASperfo is then for taking into account in order to optimize the maximize authorized takeoff weight of the aircraft.

Abstract: A method for the guidance of a rotorcraft (1) in relation to a landing point (Pp) in accordance with a landing procedure. An approach route (R) is identified and an approach trajectory (T) is calculated in accordance with a ground slope (S) imposed by the approach route (R). An upstream segment (Sam) of the approach trajectory (T) is calculated through the application of a typical trajectory, as defined in accordance with the ground slope (S), the current mass of the rotorcraft (1), and a low-noise or noise-abatement criterion relating to the noise discomfort generated by the rotorcraft (1), taking into consideration a wind model (V) that represents the change in the wind between a current position of the rotorcraft (1) and the landing point (Pp).

Abstract: A method for the guidance of a rotorcraft (1) in relation to a landing point (Pp) in accordance with a landing procedure. An approach route (R) is identified and an approach trajectory (T) is calculated in accordance with a ground slope (S) imposed by the approach route (R). An upstream segment (Sam) of the approach trajectory (T) is calculated through the application of a typical trajectory, as defined in accordance with the ground slope (S), the current mass of the rotorcraft (1), and a low-noise or noise-abatement criterion relating to the noise discomfort generated by the rotorcraft (1), taking into consideration a wind model (V) that represents the change in the wind between a current position of the rotorcraft (1) and the landing point (Pp).