 Like other members of the "Stalwart" class of ocean surveillance ships, the original mission of the "Invincible" was to patrol the oceans looking for submarines with her Surveillance Towed Array Sensor System (SURTASS), a large passive sonar array.The ship was reclassified from AGOS-10 to AGM-24 on April 4, 2000 after she was refitted as a missile range instrumentation ship.