Japan Self-Defense Forces

The Japan Self-Defense Forces (JSDF; Japanese: Jieitai) are the unified military forces of Japan, established in 1954 following Japan's post-WWII constitutional restrictions on offensive military capability. The JSDF comprises the Japan Ground Self-Defense Force (JGSDF), Japan Maritime Self-Defense Force (JMSDF), Japan Air Self-Defense Force (JASDF), and — since 2024 — the Japan Joint Operations Command and Joint Staff.

UAP-Related Role

Japanese military personnel have documented UAP encounters throughout the post-war period, though Japan's official posture long emphasised case-by-case evaluation rather than institutional study. Notable events include the 1986 Japan Airlines Flight 1628 encounter over Alaska (involving JAL rather than JSDF but prompting JSDF coordination with US authorities), the 1948 Haneda Airport radar-visual event, and the 2020 Ministry of Defence issuance of new UAP-reporting protocols for JSDF fighters.

2020 Reporting Directive

In April 2020, Japanese Defense Minister Taro Kono announced formal UAP-reporting procedures for JSDF pilots and radar operators, explicitly modelled on the US Navy's 2019 UAP reporting protocols. This directive marked Japan's most public institutional engagement with UAP to date and positioned the JSDF as a partner to US AARO in Indo-Pacific information sharing.