A method for reconstructing gusts and/or structural loads at aircraft, in particular passenger aircraft. The method includes generating an observer on the basis of a nonlinear model of the aircraft which describes the movement of the aircraft in all six degrees of freedom (DoF) and the elastic motion of the aircraft structure; continuously supplying all the data and measurements substantial for the description of the state of the aircraft to the observer; and calculating the gust velocities and structural loads (maneuver and gust loads) by the observer from the supplied data and measurements.