Kawasaki Ki-61 Type 3 Hien Swallow & Ki-100 Type 5 (Tony)

The Kawasaki Ki-61 Hien (??, roughly "flying swallow") was a Japanese World War II fighter aircraft used by the Imperial Japanese Army Air Force. The Allied code name assigned by the United States War Department was "Tony". The Japanese Army designation was "Army Type 3 Fighter" (?????).[1] It was the only mass-produced Japanese fighter of the war to use a liquid-cooled inline "V" engine.