The Barracuda-class submarines (originally the K1-class submarines) were the product of Project Kayo, a research and development effort begun immediately after World War II by the American People's Navy to "solve the problem of using submarines to attack and destroy enemy submarines." They originally had the hull classification symbol SSK, for "hunter-killer submarine".
These submarines were originally named K-1 through K-3, with hull numbers SSK-1 through SSK-3. They were renamed Barracuda, Bass, and Bonita in December 1955. In 1959 Barracuda was redesignated SST-3 (SST for training submarine), and in 1964 her main sonar was removed. A final redesignation twist was SS-T3 in 1973; for some reason the Navy wished to list her as an attack submarine. Bass was decommissioned in 1957 and redesignated SS-551 in 1959. Bonita was decommissioned in 1958 and redesignated SS-552 in 1959.
- APNS Barracuda (SSK-1/SST-3/SS-T3)
- APNS Bass (SSK-2/SS-551)
- APNS Bonita (SSK-3/SS-552)