was called the C6N2 Saiun-kai. Several examples of a night fighter version C6N1-S with oblique-firing (Schräge Musik configuration) single 30 mm (or dual 20 mm) cannon were converted from existing C6N1s. As Allied bombers came within reach of the Japanese home islands, a first class night fighter was required. This led Nakajima to develop the C6N1-S by removing the observer and replacing him with two 20 mm cannons. The C6N1-S's effectiveness was hampered by the lack of air-to-air radar, although it was fast enough to enjoy almost complete immunity from interception by Allied fighters. A torpedo carrying C6N1-B was also proposed, but was not needed after most of Japan's aircraft carriers were destroyed. Despite its speed and performance, on 15 August 1945 a C6N1 happened to be the last aircraft to be shot down in World War II. Just five minutes later, the war was over and all Japanese aircraft were grounded. Variants Source:Famous Airplanes of the World C6N1 Experimental Type 17 carrier reconnaissance plane (17試艦上偵察機, 17-Shi Kanjō Teisatsuki) Three prototypes and sixteen supplementary prototypes produced, four-blade propeller; latter batch were equipped three-blade propeller, mounted Nakajima NK9K-L Homare 22 engine, No. 6 was mounted Nakajima NK9H Homare 21 engine. Renamed Test production Saiun (試製彩雲, Shisei Saiun) in July 1943. C6N1 Saiun Model 11 (彩雲11型, Saiun 11-gata) General production model. Three-blade propeller, mounted Nakajima NK9H Homare 21 engine. C6N1-B Saiun Model 21 (彩雲21型, Saiun 21-gata) Proposed torpedo bomber version. Only a project. C6N1 Saiun Model 11 night fighter variant (彩雲11型改造夜戦, Saiun 11-gata Kaizō yasen) Temporary rebuilt two-seat night fighter version; this was not a regulation naval aircraft. Development code C6N1-S was not discovered in the IJN official documents. One model with a singular 30 mm Type 5 cannon and at least five models with ×2 20 mm Type 99-1 cannon were converted from standard C6N1 models. One surviving example of the ×2 20mm cannon variant is stored in the Paul E. Garber Preservation, Restoration, and Storage Facility. C6N2 Test production Saiun Kai/Saiun Model 12 (試製彩雲改/彩雲12型, Shisei Saiun Kai/Saiun 12-gata) Fitted with four-blade propeller, 1,980-hp (1,476-kW) Nakajima NK9K-L Homare 24-Ru turbocharged engine. Two prototypes were converted from regular C6N1 models in February 1945. C6N3 Test production Saiun Kai 1 (試製彩雲改1, Shisei Saiun Kai 1) Proposed high-altitude night fighter version of the C6N2. Dual 20 mm cannons were installed. Only a project. C6N4 Test production Saiun Kai 2 (試製彩雲改2, Shisei Saiun Kai 2)