The Kayaba Type 4 Katsuodori was a Japanese ramjet fighter, developed from a similar glider airframe, that was still on the drawing boards when World War II came to an end. Had the war continued, the Japanese planned to employ the Katsuodori as a high-altitude point defense interceptor against the American B-29 formations that attacked Japan with increasing frequency in 1944-45, in much the same way that Germany used the rocket-powered Me 163 Komet against Allied bombers over Germa any. The key difference was that the Katsuodori was powered by a ramjet, and had to be released from an already-airborne mother ship, whereas the Me 163 took off under its own power. The Katsuodori's ramjet propulsion system could not get a stationary aircraft airborne by itself, but it would have been safer than the Me 163, whose dual fuel propellant system, causing spontaneous combustion on contact, could blow both plane and pilot to bits before they left the ground