Commissioned on 7 March 1958, GRAYBACK (SSG 574) was the Navy’s first submarine to carry the Regulus II sea-to-surface missile. While operating out of Port Hueneme, Calif., on 16 September 1958 she carried out the first successful launch of a Regulus II from a submarine, which pointed the way to a revolutionary advance in the power of navies to attack land bases. GRAYBACK conducted her first deterrent missile strike mission from 21 September to 12 November 1959, patrolling secretly through Pacific waters with a full load of missiles ready for retaliation 1,000 miles inland in event of war.
Following modifications to the missile launching system and electrical circuits on 22 February 1960, GRAYBACK again took up deterrent missile strike missions. Overall she conducted nine patrols and spent more than 20 months at sea, logging well over 130,000 miles on deterrent missile strike missions. As more and more Polaris submarines became operational they assumed the deterrent functions previously assigned to GRAYBACK and her sister ships.
She decommissioned at Mare Island, Calif., on 25 May 1964.