JATO
These were used to boost the takeoff performance of their medium bombers, and the enormous 55-meter wingspan Gigant, Messerschmitt Me 321 glider, conceived in 1940 for the invasion of Britain, and used to supply the Russian front.
First experiments were held in 1937 on a 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.
[6] 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.
The strictly experimental, HWK 109-501 Starthilfe RATO system used a similar bi-propellant "hot" motor to that on the Me 163B Komet rocket fighter, adding a 20 kg mass of a combination of B-stoff hydrazine, mixed with "Br-stoff" (ligroin hydrocarbon distillate) for a main "fuel" to the T-Stoff monopropellant still destabilized with the Z-Stoff permanganate for ignition as the oxidizer, tripling the 109-500's thrust figure of 4.95 kN (at 14.71 kN/1,500 kgf) with a burn of 30 second duration.
[8][9][10] 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.
[10]: 329 After World War II JATO was often used to overcome the poor thrust of early jet engines at low speeds or for assisting heavily loaded aircraft to take off.
For example, the propeller engined Avro Shackleton, when heavily laden with fuel for long maritime surveillance flights, relied on Armstrong Siddeley Viper turbojets for takeoff.
The USAF used a modified Republic F-84, designated EF-84G, which used the MGM-1 Matador cruise missile's Aerojet General–designed, 240 kN (26 short ton) thrust-level solid fuel booster of two second thrust duration.
[16] JATO Junior bottles mounted to the engine nacelles were briefly offered as a factory option on the Beechcraft Twin Bonanza; they were promoted not as a takeoff aid, but rather as a means to extend glide distance during a forced landing in unfavorable terrain.
JATO became largely unnecessary as the take-off thrust of jet engines improved and is now rarely used even when operating heavily laden from short runways or in "hot and high" conditions.
