Abstract: According to the invention, a terrain avoidance maneuver is engaged when the alerts of a given pair of alerts are emitted simultaneously, the triggering of one of the alerts depending on the information provided by a first measurement chain and the triggering of the other alert of the pair relying on information provided by a second measurement chain, distinct from and independent of the first chain.

Abstract: An altitude profile representative of the terrain overflown by an aircraft is established. Thereafter, an altitude limit curve which comprises an intersection with the altitude profile upon the engagement of a terrain avoidance maneuver is determined. As soon as there is no longer any intersection of the limit curve with the altitude profile, the terrain avoidance maneuver is interrupted.

Abstract: A method for the determining, on board an aircraft, of an identifier of a communications center with which an aircraft crew wishes to enter into contact, includes the following operations: a) the writing, by the crew, of a radio-communications frequency to a display unit of the cockpit of the aircraft, b) the determining of surroundings of the aircraft, c) the determining of the communications centers situated in these surroundings, d) the comparing of the frequencies of these communications centers with the frequency displayed on the display unit of the cockpit, and f) when the frequency of a communications center is identical to the displayed frequency, the display on the aircraft display unit of the identifier of said communications center having a frequency identical to the displayed frequency.

Abstract: According to the invention, a terrain avoidance maneuver is engaged when the alerts of a given pair of alerts are emitted simultaneously, the triggering of one of the alerts depending on the information provided by a first measurement chain and the triggering of the other alert of the pair relying on information provided by a second measurement chain, distinct from and independent of the first chain.

Abstract: According to the invention, an altitude profile (PA) representative of the terrain overflown by the aircraft (AC) is established, and then an altitude limit curve (C) which comprises an intersection with said profile (PA) upon the engagement of a terrain avoidance maneuver is determined. As soon as there is no longer any intersection of the limit curve (C) with the altitude profile (PA), said terrain avoidance maneuver is interrupted.

Abstract: A method for the determining, on board an aircraft, of an identifier of a communications centre with which an aircraft crew wishes to enter into contact, includes the following operations: a) the writing, by the crew, of a radio-communications frequency to a display unit of the cockpit of the aircraft, b) the determining of surroundings of the aircraft, c) the determining of the communications centers situated in these surroundings, d) the comparing of the frequencies of these communications centers with the frequency displayed on the display unit of the cockpit, and f) when the frequency of a communications centre is identical to the displayed frequency, the display on the aircraft display unit of the identifier of said communications centre having a frequency identical to the displayed frequency.