The Kawasaki Ki-45 Toryu (屠龍, "Dragonslayer") was a two-seat, twin-engine heavy fighter used by the Imperial Japanese Army in World War II. The army gave it the designation "Type 2 Two-Seat Fighter"; the Allied reporting name was "Nick". Originally serving as a long-range escort-fighter, the design — as with most heavy fighters of the period — fell prey to smaller, lighter, more agile single-engine fighters. As such, the Ki-45 instead served as a day and nighttime interceptor and strike-fighter. Design and development In response to the rapid emergence in Europe of twin-engine heavy fighters such as the Messerschmitt Bf 110, the army ordered development of a twin-engine, two-seat fighter in 1937, and assigned the proposal by Kawasaki Shipbuilding the designation of Ki-38. This only went as far as a mock up, but by December of that year the army ordered a working prototype as the Ki-45, which first flew in January 1939. Results from the test flights, however, did not meet the army's expectations. The Ha-20 Otsu engine was underpowered and failure-prone, while the airframe suffered from nacelle stall. The Ki-45 did not enter service, but the army, insistent on having a working twin-engine fighter, ordered Kawasaki to continue development. Kawasaki responded by replacing the engines with the proven Nakajima Ha-25. Flight tests were promising. In October 1940, the army ordered continued improvements such as switching to 805 kW (1,080 hp) Mitsubishi Ha-102 engines. This craft, designated Ki-45 Kai, was completed in September 1941 and was officially adopted for use by the army in February 1942 as the "Type 2 two-seat fighter". The prototype of a single-seat fighter variant, the Ki-45 II, was also built; development continued under the designation Ki-96. Operational history The Ki-45 was initially used as a long-range bomber escort. The 84th Independent Flight Wing (Dokuritsu Hikō Chutai) used them in June 1942 in attacks on Guilin, where they encountered, but were no match for, Curtiss P-40s flown by the Flying Tigers. In September of the same year, they met P-40s over Hanoi with similar results. It became clear that the Ki-45 could not hold its own against single-engine fighters in aerial combat. It was subsequently deployed in several theaters in the roles of interception, attack (anti-ground as well as anti-shipping) and fleet defense. Its greatest strength turned out to be as an anti-bomber interceptor, as was the case with the Bf 110 in Europe. In New