Long March 3 Launch Vehiclel “长征三号”运载火箭 Long March 3 (LM-3) is a three-stage launch vehicle, primarily intended for sending spacecraft into Geosynchronous Transfer Orbit with the GTO capacity of l. 5 metric tons and the length of 44. 56m. The diameters of the first and second stages of LM-3 are the same, 3. 35m and the third stage, 2.25m. The development of the first and second stages is based on the first and second stages of LM-2C. The first two stages burn UDMH/N204 as propellants, while the third stage of LM-3 is powered by a cryogenic engine, using liquid oxygen ( LOX) and liquid hydrogen( LH2 ) as propellants .The launch site is Xichang Space Launch Center. The C2-3 launch vehicle won a perfect success in April, 1984. The vehicle also marked the first use of a high technology upper stage. On April 7, 1990, LM-3 delivered the first foreign communication satellite, Asia Sat l, made by the U. S. Hughes Corporation, into a predetermined GTO. It was a total success and marked the real entrance of Long March launch vehicles for China into the international commercial launch service market. “长征三号”运载火箭是三级火箭,主要用于发射地球同步轨道有效载荷,运载能力为1.5吨。全长44. 56米,一、二子级直径3.35米、三子级直径2. 25米。其一、二级是在“长征二号丙”运载火箭的一、二子级的基础上研制的,使用偏二甲肼( UDMH)和四氧化二氮(N204)作为推进剂,其三子级采用了低温高能液氢( LH2)液氧(LOX)发动机。“长征三号”火箭在西昌卫星发射中心(XSLC)进行发射。“长征三号”运载火箭在1984年4月进行首次飞行,成功地将“东方红二号”试验通信卫星送入预定地球同步转移轨道,标志着中国运载火箭技术跨人世界先进行列。该火箭曾于1990年4月7日成功地将美国休斯公司制造的“亚洲1号”卫星送人地球同步转移轨道,是中国运载火箭发展上的一个重要里程碑。在此之后,“长征三号”运载火箭成功地发射了包括“亚太一号卫星”、“亚太一号甲卫星”、“风云二号卫星”等在内多颗国内外卫星。
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