A method implemented by computer for calculating a lateral approach trajectory of an aircraft, comprises the steps of receiving selection of a landing runway; determining a zone Z1, the zone defining trajectory limits to carry out a last turn with a view to landing on the indicated runway; receiving indication of a trajectory point FF defining a point of alignment of the aircraft; determining a joining trajectory bound for a point FAF2, the joining trajectory going from the aircraft to the point FAF2 and then to the point FF and then to the indicated landing runway without passing through the zone Z1. Developments describe the use of a zone Z2 associated with visibility conditions, the calculation of the energy to be dissipated, the use of a predefined descent profile, the emission of alerts and trajectory adaptations by increasing the length of the joining trajectory or use of the airbrakes.