To bring an aircraft in flight to a runway, an automatic trajectory generation system obtains a procedure, called STARI procedure, which provides a final trajectory flyable by the aircraft to land on the runway, such that from the entry point of the final trajectory or from any point above it, a holding loop pattern of a predefined shape is flyable in order to dissipate energy if necessary. The automatic trajectory generation system then computes a lateral trajectory, avoiding any terrain relief, meteorological obstacles and military zones, between the current position of the aircraft and the entry point or a point above it, based on performance adapted to an operational state of the aircraft. An overall trajectory is thus obtained, by linking the computed lateral trajectory and the final trajectory of the STARI procedure, including iterations of the holding loop pattern if necessary.