| Ki-21 | |
|---|---|
 Mitsubishi Ki-21 | |
| General information | |
| Type | Heavy bomber |
| Manufacturer | Mitsubishi Heavy Industries |
| Primary users | Imperial Japanese Army Air Service |
| Number built | 2,064 units (excluding Ki-57) |
| History | |
| Introduction date | 1938 |
| First flight | 18 December 1936 |
| Retired | 1945 |
| Variants | Mitsubishi Ki-57 |
The Mitsubishi Ki-21, formal designation "Type 97 Heavy Bomber" (九七式重爆撃機, Kyūnana-shiki jūbakugekiki) was a Japanese heavy bomber during World War II. It began operations during the Second Sino-Japanese War participating in the Nomonhan Incident, and in the first stages of the Pacific War, including the Malayan, Burmese, Dutch East Indies and New Guinea Campaigns. It was also used to attack targets as far-flung as western China, India and northern Australia. The Allies designated it under the reporting names "Sally" /"Gwen".