A ground proximity warning system for an aircraft includes a plurality of alarm generators, each able to generate an alarm by verifying evolution conditions of the aircraft specific to each alarm generator, the verification using data obtained from at least one measuring sensor of the aircraft. The ground proximity warning system includes a unit for selective deactivation of at least some of the alarm generators, able to be implemented during a search and rescue mission carried out by the aircraft, and an auxiliary alarm generator, capable of emitting a ground proximity alarm based on the safety height chosen for the search and rescue mission, when the selective deactivation unit is implemented.