Bücker Bü 131 Jungmann Kokusai Ki-86A

The Kokusai Ki-86 was the Jungmann version intended for the Imperial Japanese Army. History of War explains that the Navy had been the first to take an interest in the Bü 131 and had put it into production as the Kyūshū K9W1; the Army, which needed to replace its Tachikawa Ki-17 primary trainer, was impressed by the German biplane's performance. The rivalry between the two services meant that, instead of sharing Kyūshū's production, the Army ordered its own version from Kokusai Kōkū Kōgyō, which received the designation Ki-86 and the official name Army Type 4 Primary Trainer.

The Ki-86A was powered by the 110 hp Hitachi Ha-47 11, an engine derived from the Hirth HM 504, and according to History of War it was virtually identical to the Bü 131B: its wingspan was two inches shorter, it was some nine miles per hour faster and its ceiling was about 3,000 feet higher. The source's data sheet gives it a span of 24 feet and almost one inch, a length of 21 feet eight inches, 902 lb empty and 1,409 lb loaded, a top speed of 112 mph, a cruising speed of 75 mph at 3,280 feet, a ceiling of 12,730 feet and a range of 373 miles; the census records them converted to metric units.

Between 1943 and 1945 Kokusai built 1,037 aircraft, a figure on which History of War, the English and German Wikipedias and the Air Britain Digest all agree, making the Ki-86 the most numerous Jungmann variant from a single manufacturer. The Fundación Infante de Orleans speaks of 1,254 Japanese Jungmann in total, without splitting Army and Navy. It served with the Army's flying schools until the end of the war. An all-wooden derivative, the Ki-86B, got no further than a single prototype.