Method and device for assisting in the piloting of an aircraft to observe a required time of arrival

A system for assisting in a piloting of an aircraft in order to observe a required time of arrival at a waypoint during a flight of the aircraft according to a predetermined flight plan, this flight plan comprising a nominal speed profile of the aircraft comprising at least two distinct flight segments for each of which there are defined a nominal flight speed, a maximum flight speed and a minimum flight speed of the aircraft, the system comprising:

• a flight management computer which comprises a processing unit configured to determine an effective speed profile of the aircraft, this effective speed profile comprising flight segments similar to those of the nominal speed profile, said determination of the effective speed profile comprising:
• a computation, for each segment of the nominal speed profile, of a corrective term corresponding to a product of a correction coefficient by a difference between one of the maximum flight speed or the minimum flight speed defined for this segment and the nominal flight speed corresponding to this segment, the correction coefficient being a correction coefficient common to all segments of the nominal speed profile;
• and
• a computation, for each segment of the effective speed profile, of a setpoint speed equal to a sum of the nominal flight speed defined for the corresponding segment of the nominal speed profile and of the corrective term computed for a corresponding segment of the nominal speed profile,
• a guidance computer of the aircraft configured to guide the aircraft according to the effective speed profile determined by the processing unit of the flight management computer.