The US-1A's first rescue was from a Greek vessel in 1976. Despite having been envisioned largely to perform air-sea rescues of military personnel, the US-1A has mostly been involved in civilian assistance operations. Between 1976 and 1999, Japan's US-1A fleet has reported been used in over 500 rescues and were responsible for the saving of 550 lives. The US-1A was retired on December 13, 2017 when the last example in JMSDF service conducted its final flight. According to aviation periodical Air International, a total of 827 people have been rescued by US-1s since the type had entered service during 1976. It has been succeeded in its role by the modernised US-2.