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JATO (acronym for jet-assisted take off), is a type of assisted take-off for helping overloaded aircraft into the air by providing additional thrust in the form of small rockets. The term ''JATO'' is used interchangeably with the (more specific) term RATO, for ''Rocket-Assisted Take Off'' (or, in RAF parlance, RATOG for ''Rocket-Assisted Take Off Gear''). ==Early experiments and World War II== Early experiments using rockets to boost gliders into the air were conducted in Germany in the 1920s (Lippisch Ente), and later both the Royal Air Force and the Luftwaffe introduced such systems in World War II.〔"For operations from small flight decks with heavy loads, rocket-assisted take-offs were necessary." http://uboat.net/allies/aircraft/swordfish.htm〕 The British system used fairly large solid fuel rockets to shoot planes (typically the Hawker Hurricane) off a small ramp fitted to the fronts of merchant ships, known in service as Catapult armed merchantmen (or CAM Ships), in order to provide some cover against German maritime patrol planes. After firing, the rocket was released from the back of the plane to fall into the water and sink. The task done, the pilot would fly to friendly territory if possible or parachute from the plane, hopefully to be picked up by one of the escort vessels. Over two years the system was only employed nine times to attack German aircraft with eight kills recorded for the loss of a single pilot. The Luftwaffe also used the technique with both liquid-fueled and solid fuel, often jettisonable rocket motors in order to help their small bombers, and the enormous ''Gigant'', Messerschmitt Me 321 glider, conceived in 1940 for the invasion of Britain, and used to supply the Russian front which also had air tow assistance from up to three Messerschmitt Bf 110 heavy fighters in a so-called ''Troika-Schlepp'' arrangement, into the air with loads that would have made the takeoff run too long otherwise, but with much attendant risk of aerial collision from the trio of vee-formation Bf 110s involved in a simultaneous towplane function. This became especially important late in the war when the lengths of usable runways were severely curtailed due to the results of Allied bombing. Their system typically used Walter HWK 109-500 or -501 ''Starthilfe'' ("start-help") liquid-fuel monopropellant rocket engines driven by chemical decomposition of "T-Stoff", essentially almost pure hydrogen peroxide. A parachute pack at the blunt-contour front of the motor's exterior housing was used to slow its fall after being released from the plane, so the system could be re-used. First experiments were held in 1937 on an Heinkel He 111, piloted by test-pilot Erich Warsitz at Neuhardenberg, a large field about 70 kilometres east of Berlin, listed as a reserve airfield in the event of war.〔Warsitz, Lutz: (''THE FIRST JET PILOT - The Story of German Test Pilot Erich Warsitz'' (p. 45), Pen and Sword Books Ltd., England, 2009 )〕 Other German experiments with JATO were aimed at assisting the launch of interceptor aircraft such as the Messerschmitt Me 262C, as the ''Heimatschützer'' special versions, usually fitted with either a version of the Walter HWK 109-509 liquid fuelled rocket engine from the Me 163 ''Komet'' program either in the extreme rear of the fuselage or semi-"podded" beneath it just behind the wing's trailing edge, to assist its Junkers Jumo 004 turbojets, or a pair of specially rocket-boosted BMW 003R combination jet-rocket powerplants in place of the Jumo 004s, so that the Me 262C ''Heimatschützer'' interceptors could reach enemy bomber formations sooner. Two prototypes of the ''Heimatschützer'' versions of the Me 262 were built and test flown, of the three designs proposed. In early 1939, the United States National Academy of Sciences provided $1,000 to Theodore von Kármán and the Rocket Research Group (including Jack Parsons, Frank Malina, Edward Forman and Apollo M. O. Smith) at the Guggenheim Aeronautical Laboratory to research rocket-assisted take-off of aircraft. This JATO research was the first rocket research to receive financial assistance from the U.S. government since World War I when Robert Goddard had an Army contract to develop solid fuel rocket weapons.〔(【引用サイトリンク】title=Orders of Magnitude - A History of the NACA and NASA, 1915-1990, Ch. 2 )〕 In late 1941 von Kármán and his team attached several 50-pound thrust, solid fuel Aerojet JATOs to a light Ercoupe plane, and Army Captain Homer Boushey took off on test runs. On the last run they removed the propeller, attached six JATO units under the wings, and Boushey was thrust into the air for a short flight, the first American to fly by rocket power only. Both armed services used solid fuel JATO during the war.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「JATO」の詳細全文を読む スポンサード リンク
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