T-7 (missile)
T-7 ( Chinese 探空火箭7號 / 探空火箭7号 , Pinyin Tànkōng Huǒjiàn 7 Hào , German "sounding rocket 7") is the name of the first in the People's Republic of China developed sounding rocket . The T-7, first launched on September 13, 1960, was able to reach a height of 58 kilometers with a payload of 25 kg. The single-stage, liquid fuel-powered, unguided T-7 was 8 meters long, had a take-off weight of 1,138 kg and was 45 centimeters in diameter. The thrust could be increased by solid and later by liquid fuel boosters .
development
The development by the engineering office for mechanical and electrical engineering in Shanghai under Wang Xiji began in October 1959. After a few drafts (T-1, T-2 etc.), which were due to technical reasons and delivery difficulties - they were just about to make a big leap forward - could not or only partially be realized, the reduced two-stage prototype T-7M was tested first (the "M" stood for 模型 火箭, Pinyin Móxíng Huǒjiàn , ie "model rocket"). The 5,345 m long model rocket with a diameter of 45 cm and a takeoff weight of 190 kg had two stages: a solids booster, and then the actual rocket, which used a self-igniting Diergol propellant with aniline and nitric acid as an oxidizer, which gave the engine a Thrust of 2.26 kN awarded. The missile had no guidance system; their direction of flight was only determined by the launch pad. When the booster stage burned down, the main engine automatically ignited, which carried the rocket to the apex of the flight path. There the head of the rocket separated from the body and both components were parachuted back to Earth, where they could be retrieved; the booster of the T-7M fell unchecked to the ground or into the sea.
The start near the village Dongjin (东进村) in the large village Laogang, a few kilometers south of the present-day Shanghai Pudong International Airport , carried out by a simple steel framework, the "control center" consisted of a protected with sandbags straw hut and the compressed air for the compressed gas promotion of Fuel was generated with a bicycle pump. After a first failed attempt in January 1960, the prototype reached an altitude of 8 km on February 19, 1960, whereby the antenna for tracking the missile had to be adjusted by hand by several men. On May 28, 1960, Mao Zedong attended the Shanghai New Technology Fair. He was told that the success had been achieved without the help of Russian experts and that the developers were almost all under 25 years of age. Mao was impressed and wished for a summit height of 200 km.
In March 1960, work began on a launch platform for the final T-7 in southern Anhui Province . In addition to the Shanghai engineering office, the Institute of Geophysics of the Chinese Academy of Sciences was also involved in the development. When it was first launched in September 1960, solid fuel boosters were used. After several, not always successful launches, the rocket reached an altitude of 58 km on November 23, 1961. At this altitude she could make weather observations. 24 T-7s had been launched by 1965. Nine of them were weather missiles.
Improved models
In May 1961, the Defense Technology Commission of the People's Liberation Army commissioned the Chinese Academy of Sciences to create a profile of the high atmosphere up to an altitude of 100 km: temperature, air pressure , air density and winds. For this purpose, the construction of an improved version of the T-7, the T-7A , was approved in January 1962 , which, in addition to the actual rocket with a liquid propulsion system, had a solid fuel booster as the first stage, with altitudes of over 100 km, i.e. into the ionosphere . The Institute for Geophysics developed a. a. a payload used to measure electron density in the ionosphere. The first flight of a T-7 with meteorological payloads took place on August 4, 1963, the first test flight of the T-7A in December 1963. The T-7A was 10 m long, weighed 1.3 tons and developed a thrust of 46 kN . The upper stage, powered by liquid fuel, and the payload of up to 170 kg (at 60 km altitude; 40 kg at 110 km altitude) could return to earth on a parachute and be reused. The missile was used from December 1963 to 1969.
After Yuri Alexejewitsch Gagarin became the first person to circle the earth on April 12, 1961, enthusiasm for space travel also grew in China. It was decided to conduct flight experiments with live test animals. On July 19, 1964, a specially modified T-7A, the T-7A / S1 - the "S" stands for 生物 or shēngwù , ie "living beings" - eight mice and twelve test tubes with fruit flies , single cells and Taking enzymes up to 70 km in a suborbital flight . After rats and mice were sent back to the high atmosphere on June 1st and 5th, 1965, the dogs Xiaobao (小 豹, little panther ) and Shanshan (珊珊, elegant striding) traveled on the 15th. or July 28, 1966 with a T-7A / S2 , which had a larger payload capsule, in which, in addition to telemetry for the body functions of the animals, an 8-mm camera was installed, which monitored the animals' reactions during take-off and in the Filmed weightlessness. The film was a 16mm Japanese film that was split by hand. Both dogs, which had been trained for the space conditions and to stay in the narrow capsule for a long time, survived the flights safely. The return to earth was made by parachute. With no helicopter available - China's first helicopter, the Yan'an-2 , did not enter service until 1975 - it took the crew a long time to get to the landing site on foot. The animals, however, were unimpressed. After the holding mechanism was released, the dogs and the accompanying mice jumped out of the capsule, which was documented by a cameraman with imported GDR color film. The dogs were then brought back to Beijing by Bei Shizhang , director of the Institute of Biophysics at the Academy of Sciences, where they were later mated and gave birth to healthy puppies.
The three-stage T-7 / GF-01A took off on August 8 and 20, 1968 to test the ignition device for the solid rocket engine of the third stage of the planned Changzheng 1 satellite launcher. Both attempts succeed. On August 8, the “solid rocket engine 01A” (固体 火箭 发动机, Pinyin Gùtǐ Huǒjiàn Fādòngjī , hence “GF-01A” for short) fired as planned at a height of a few dozen kilometers, and on August 20 at an altitude of 320 km.
successor
The T-7 was replaced by the HP2 , the first stage of which used two T-7A engines in tandem. It was used for routine measurements at altitudes up to 70 km.
See also
Web links
- T-7 in the Encyclopedia Astronautica (English)
Individual evidence
- ↑ 解密 603 ： 中国 探空 火箭 发祥地. In: news.sina.com.cn. June 13, 2012, Retrieved September 28, 2019 (Chinese).
- ↑ 王希 季: 箭 击 长空 忆 当年. In: cas.cn. Retrieved November 22, 2019 (Chinese).
- ↑ T-7 in the Encyclopedia Astronautica (English)
- ↑ T-7A in the Encyclopedia Astronautica (English)
- ↑ 中国 航天 第一 村: 空间 科学 探测 第一步 从 安徽 这里 迈出. In: mzfxw.com. July 20, 2019, Retrieved December 4, 2019 (Chinese).
- ↑ T-7A-S in the Encyclopedia Astronautica (English)
- ↑ 贝 时 璋 院士 ： 开展 宇宙 生物学 研究. In: tech.sina.com.cn. November 15, 2006, Retrieved December 4, 2019 (Chinese).
- ↑ T-7A in the Encyclopedia Astronautica , accessed on September 27, 2019 (English).
- ↑ T-7 / GF-01A in the Encyclopedia Astronautica (English)
- ↑ 王希 季: 箭 击 长空 忆 当年. In: cas.cn. Retrieved November 23, 2019 (Chinese).
- ↑ HP2 in the Encyclopedia Astronautica (English)