In the 1950s, Japan signed the Japan-US Security Treaty. The GHQ forces stationed in Japan remained as the US Forces Japan, but with the outbreak of the Korean War, the US was no longer able to focus on Japan. The Self-Defence Forces were established in response to the US demand for Japan to rearm, and the F4U Corsair began service in 1954. As the United States began deploying replacement F4U-4 and F9F models, the surplus F4U-1D aircraft were transferred to Japan. These aircraft were used for over a decade. At times, they were deployed alongside U.S. Navy aircraft carriers for training purposes, but the information about this was not made public until 30 years after the Corsair's retirement, on 31 February 1995.
