Method for securing the operation of a synthetic viewing system of an aircraft, associated computer program product and system

A method for securing an operation of a synthetic vision system of an aircraft, the synthetic vision system providing a synthetic display of an outside environment of the aircraft according to a field of view, using first projection rules generated as a function of first measurements of a current position and a current attitude of the aircraft;

• the method comprising the following steps:
• determining at least one control object in the field of view of the synthetic vision system and, for each determined control object, determining at least one control point belonging to the control object;
• verifying a coherence of the display of the synthetic vision system, said display comprising an outline of each determined control object by using the first projection rules, said verification step comprising the following sub-steps carried out for at least one control point:
• recovering a first position corresponding to the displayed position of this control point on the corresponding outline of the display of the synthetic vision system;
• determining a second position of this control point on the display of the synthetic vision system, using second projection rules generated independently of the first projection rules;
• and
• comparing the first and second positions to determine whether or not the display of the synthetic vision system is inconsistent, the display of the synthetic vision system being inconsistent when the second position differs from the first position by at least a predetermined threshold;
• and
• when the display of the synthetic vision system is determined as being inconsistent, changing the display of the synthetic vision system by another display.