About this Unit
USS Grayback (SSG-574) was a Grayback-class submarine commissioned by the United States Navy in 1958. Originally designed as a guided missile submarine, she was equipped to launch Regulus I and II nuclear cruise missiles, serving as a critical component of the Navy's early sea-based strategic deterrent during the Cold War. In the mid-1960s, Grayback was converted to serve as an amphibious transport submarine, supporting special operations and covert missions, including carrying SEAL teams and UDT personnel. She remained active until her decommissioning in 1984, after which she was eventually sunk as a target in 1986.
Historical Facts
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Unique Role as a Cruise Missile Submarine: USS Grayback (SSG-574) was one of only two submarines specifically built to carry and launch Regulus I nuclear cruise missiles, making her a key part of America’s early nuclear deterrent at sea.
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Namesake Legacy: She was the second U.S. Navy ship named after the grayback fish, continuing the legacy of her World War II predecessor, USS Grayback (SS-208).
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First Launch in 1958: Grayback was launched on July 2, 1957, and commissioned on March 7, 1958, at Mare Island Naval Shipyard, California.
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Regulus Missile Operations: She conducted numerous deterrent patrols in the Pacific, armed with up to two Regulus I missiles stored in special hangars on her deck.
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Converted to a Special Operations Platform: In the mid-1960s, Grayback was converted to carry Navy SEALs, Underwater Demolition Teams (UDTs), and their Swimmer Delivery Vehicles (SDVs), becoming one of the Navy’s first dedicated special operations submarines.
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Innovative Dry Deck Shelter: Grayback was fitted with a large hangar and dry deck shelter, allowing covert deployment and recovery of special forces underwater, a pioneering capability at the time.
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Vietnam War Operations: She supported secret reconnaissance and sabotage missions during the Vietnam War, inserting and extracting covert teams along enemy coastlines.
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Longest Submarine in the World (Briefly): After her conversion for special operations, Grayback was, for a time, the longest submarine in the world at 317 feet.
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Decommissioned & Fate: Grayback was decommissioned in 1984 and later sold for scrap, ending her unique and varied career.
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Inspiration for Future Designs: The special operations techniques and equipment developed aboard Grayback paved the way for the later “SSN-21” class and the Ohio-class guided missile submarines adapted for special operations.
