Жапондық Kikka реактивтік ұшағының прототипі

Japanese jet attack aircraft prototype

The Nakajima Kikka (橘花), initially designated Kōkoku Nigō Heiki (皇国二号兵器), was Japan's first turbojet powered aircraft. It was developed late in World War II, and the single completed prototype flew only once, in August 1945, before the end of the conflict.

The first prototype commenced ground tests at the Nakajima factory on 30 June 1945. The following month it was dismantled and delivered to Kisarazu Naval Airfield where it was re assembled and prepared for flight testing. The first flight took place on 7 August 1945 (the day after Hiroshima was bombed by atomic bomb), with Lieutenant Commander Susumu Takaoka at the controls. The aircraft performed well during a 20 minute test flight, with the only concern being the length of the takeoff run. For the second test flight, four days later (4 days prior to Japan's declaration of surrender), rocket assisted take off (RATO) units were fitted to the aircraft. The pilot had been uneasy about the angle at which the rocket tubes had been set, but with no time to correct them they decided to simply reduce the thrust of the rockets from 800 kg to only 400 kg. Four seconds into take off the RATO was actuated, immediately jolting the aircraft back onto its tail leaving the pilot with no effective tail control. After the nine second burning time of the RATO ran out the nose came down and the nose wheel contacted the runway, resulting in a sudden deceleration, however both engines were still functioning normally. At this point the pilot opted to abort the take off, but fighting to brake the aircraft and perform a ground loop only put him in danger of running it into other installations. Eventually the aircraft ran over a drainage ditch which caught the tricycle landing gear, the aircraft continued to skid forward and stopped short of the water's edge. Before it could be repaired Japan had surrendered and the war was over. At this point, the second prototype was close to completion, and approximately 23 more airframes were under construction. Five of these were two seat trainers.

After the war, airframes 3, 4, and 5 (and possibly other partial airframes) were brought to the U. S. for study. Today, two examples survive in the National Air and Space Museum: The first is a Kikka that was taken to the Patuxent River Naval Air Base, Maryland for analysis. This aircraft is very incomplete and is believed to have been patched together from a variety of semi completed airframes. It is currently still in storage at the Paul E. Garber Preservation, Restoration and Storage Facility in Silver Hill, Maryland. The second Kikka is on display at the NASM Udvar Hazy Center in the Mary Baker Engen Restoration Hangar. Correspondence in 2001 with Japanese propulsion specialist Kazuhiko Ishizawa theorized that Nakajima constructed the Museum’s Kikka airframe for load testing, not for flight tests. This may explain why the engine nacelles previously fitted on the Museum’s Kikka airframe are too small to enclose the Ne 20 engines. Furthermore, Susumu Watanabe, who was in charge of engine outfitting for the Kikka, recalled that the engine nacelles of the strength tester were the same as the standard aircraft, and that the strength tester was stressed until failure. Based on this information, the mock nacelles were potentially added for display purposes after transit to the United States. Two Ne 20 jet engines had been taken to the US and sent for analysis to the Chrysler Corporation in 1946. This was only revealed in 2005 by W. I. Chapman, who was in charge of the project at the time. A working engine was assembled with the parts of the two Ne 20s, and tested for 11 hours and 46 minutes. A report was issued on 7 April 1947, titled "Japanese NE 20 turbo jet engine. Construction and performance". The document is now on display at the Tokyo National Science Museum.