Abstract: The invention relates to systems for preventing off-normal situations when there is a possibility that an aircraft penetrates into a dangerous area of the vortex shedding of a vortex generator. The inventive system consists of information sub-systems for recording and storing information on the expected relative position of the aircraft and trailing vortex areas in line with danger criteria which are specified by a user and concern dangerous aerodynamic forces and torques effecting the aircraft and induced by the trailing vortex of vortex generators, and for conveying said information to said user, who can be the aircraft crew and/or flight attendants, at a preventive distance from the aircraft and at a forecast moment. Said information can be visualised in a human-readable form and in a volume sufficient for forming a directive signal for carrying out a flight manoeuvre by the aircraft in order to move away from the dangerous trailing vortex area.