KI 43 Type 1 "OSCAR" fighter undergoing restoration

"The Ki-43 Type 1 Hayabusa (Peregrine Falcon) was the most widely flown fighter of the Japanese Army Air Force during the war (Allied code name Oscar). Entering squadron service shortly before the Pearl Harbor attack, the Oscar was highly manoeuvrable with a good rate of climb, but somewhat underpowered and, despite updates, unable to compete effectively with U.S. fighters in the latter stages of the war. An official USAAF analysis, however, described later models as "an increasingly dangerous opponent." The Oscar saw combat in all Pacific areas where the Japanese Army conducted air operations, and most Japanese Army Aces scored most of their kills in this aircraft. At the end of the war the Oscar was employed with the Army's Taiatari (suicide) units." From the link below