A man-machine interface for assisting a pilot during takeoff or landing of an airborne vehicle in reduced external visibility includes a display which represents a virtual scenario from the perspective of a virtual observer who is himself located behind the airborne vehicle and is in the same flight attitude as the airborne vehicle itself. The virtual scenario includes a base plane which symbolizes an idealized ground surface, calculated from the instantaneous value of the altitude above ground and the instantaneous flight attitude data of the aircraft. The base plane is bounded by an artificial horizon and is continuously updated with the instantaneous flying state data and the instantaneous height above ground. The virtual scenario also includes a symbol which represents the airborne vehicle, and the position of the symbol relative to the base plane represents the current flight attitude and the instantaneous height of the airborne vehicle above ground.