Abstract: There is provided an aircraft flight control system comprising: a computing arrangement including an input interface and an output interface; wherein in operation the computing arrangement executes instructions to provide indications related to an estimated atmospheric contamination risk to at least one aircraft at selected locations and altitudes or pressures, by (i) receiving at least one aircraft flight plan data from the input interface; wherein at least one aircraft flight plan data includes at least one of time, a pressure or an altitude, a trajectory and a location representing at least one aircraft flight; (ii) determining the estimated atmospheric contamination risk using a measure of the at least one atmospheric contaminant for the at least one aircraft flight based upon a location, an altitude or pressure, a trajectory and a time information extracted from the at least one aircraft flight plan data; and (iii) providing, via the output interface, a resultant indication related to the estimated atmos