Piloting assistance system and method for an aircraft

A piloting assistance system for an aircraft, said system comprising a flight management computer for managing a flight of the aircraft and a guidance computer for guiding the aircraft, wherein the flight management computer is configured so as to:

• determine an initial speed profile along a current flight plan of the aircraft and transmit, to the guidance computer, a speed setpoint corresponding to the initial speed profile so as to pilot the aircraft in accordance with said initial speed profile in a managed mode;
• in response to a reception of an RTA constraint at a point of the flight plan, determine an RTA speed profile for complying with said RTA constraint and transmit, to the guidance computer, an RTA speed setpoint corresponding to the RTA speed profile, so as to pilot the aircraft in accordance with said RTA speed profile in the managed mode,
• wherein the guidance computer is configured so as to:
• accept the reception of a setpoint speed, called selected speed, input by a flight crew member by way of a human-machine interface of said guidance computer when the guidance computer is piloting the aircraft in accordance with the RTA speed setpoint in managed mode;
• and
• activate a selected mode in which said guidance computer pilots the aircraft in accordance with the selected speed,
• wherein the flight management computer is furthermore configured so as, in response to the activation of the selected mode in which the guidance computer pilots the aircraft at the selected speed, to:
• determine a deselection point defined so as to allow the RTA constraint to be complied with when the aircraft is flying at the selected speed between a current position of the aircraft and the deselection point, and then in accordance with a predetermined speed profile between the deselection point and the point of the flight plan with which the RTA constraint is associated;
• and
• command a display, on a navigation screen in a cockpit of the aircraft, of a symbol corresponding to the current position of the aircraft, of a symbol corresponding to the position of the point of the flight plan with which the RTA constraint is associated, and of a symbol corresponding to the position of the deselection point.