during november 1981, kawasaki was selected as the main contractor to design and manufacture a suitable trainer aircraft, which was initially designated as the "ka-850", to meet the needs of japan's "mt-x" program, having beaten out rival bids from mitsubishi and fuji. the mt-x program had been launched to procure a replacement for the aging lockheed t-33 and fuji t-1 jet trainer aircraft then in service in the japan air self defense force (jasdf). furthermore, there was also a desire for the prospective trainer aircraft to take over some of the syllabus that was being handled by the contemporary mitsubishi t-2, a supersonic trainer variant of the mitsubishi f-1 fighter aircraft. the initial program planned for a production run of 220 aircraft and an entry into service date of 1988.