The Mitsubishi Ki-51 (Army designation "Type 99 Assault Plane"; Allied reporting name "Sonia") was a light bomber/dive bomber in service with the Imperial Japanese Army during World War II. It first flew in mid-1939. Initially deployed against Chinese forces, it proved to be too slow to hold up against the fighter aircraft of the other Allied powers. However, it performed a useful ground-attack role in the China-Burma-India theater, notably from airfields too rough for many other aircraft. As the war drew to a close, the Japanese began using them in kamikaze attacks. Total production was around 2,385 units.
Indonesian Air Force Ki-51 "Guntei" at Dirgantara Mandala MuseumIndonesian Air Force - In late 1945, the Indonesian People's Security Army (TKR) captured some aircraft at Japanese bases, including Bugis Air Base in Malang. Most aircraft were destroyed during the Indonesian National Revolution of 1945–1949. Two Yokosuka K5Y "Cureng", and a Ki-51 "Guntei" carried out a bombing operation against the Dutch on July 29, 1947.
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Soumille, Jean-Claude (September 1999). "Les avions japonais aux couleurs françaises" [Japanese Aircraft in French Colors]. Avions: Toute l'Aéronautique et Son Histoire (in French) (78): 6–17. ISSN1243-8650.