The Mitsubishi F-15J/DJ Eagle is a twin-engine, all-weather air superiority fighter based on the McDonnell Douglas F-15 Eagle in use by the Japan Air Self-Defense Force (JASDF). The F-15J was produced under license by Mitsubishi Heavy Industries. The subsequent F-15DJ and F-15J Kai variants were also produced. Japan is the largest customer of the F-15 Eagle outside the United States. In addition to combat, F-15DJ roles include training. The F-15J Kai is a modernized version of the F-15J. Development In June–July1975, the Japan Defense Agency (JDA, now Ministry of Defense) examined the McDonnell Douglas F-15 Eagle as one of the 13 candidates for the replacement of the F-104J/DJ Starfighter and F-4EJ Phantom II. A single-seat F-15C and a twin-seat F-15D were evaluated at Edwards Air Force Base, and in , the F-15 has announced the winner, with the government intending to purchase 187 F-15J/DJs. By April 1978, Mitsubishi Heavy Industries was designated as the primary contractor and licensing for the F-15C/D was achieved. After congressional review, the Department of Defense (DoD) withheld the aircraft's electronic warfare and engine systems from the licensing. Initially, the aircraft were produced in the U.S. and exported to Japan. This initial export production contributed to aircraft development under the defense industry of Japan while facilitating base production of aircraft, achieving the goal of producing a fighter to Japan's requirements. The Japan Air Self-Defense Force (JASDF) acquired 203F-15Js and 20F-15DJs, of which 2F-15Js and 12F-15DJs were built by McDonnell Douglas in St. Louis, Missouri. Dubbed the "Peace Eagle" by the DoD FMS program, the first F-15J built in St. Louis was delivered to the United States Air Force for its first flight on , and a subsequent cruise on 15 July to Japan. Additionally, 8F-15Js were manufactured in large components and shipped to Japan for final assembly by Komaki of Mitsubishi, the first of these (serial number 12–8803) making its maiden flight on . Companies divided the remainder share and produced it under license from 1981, with final assembly of aircraft performed by Mitsubishi. In 1980, the Japanese government applied for access to advanced technology through the U.S.-Japan Forum (S&TF) but this was rejected. The JDA and the DoD held annual meetings about relaxation of the regulation after a program was started. In these meetings, the DoD official gave an answer that permitted access to initially prohibited technology of various types including composite material. In the