长征四号运载火箭的主要特点

The Features of LM-4 Launch Vehicle

长征四号运载火箭是中国长征运载火箭系列的一种型号。1988年,长征四号运载火箭首次使用即告成功,从而使中国长征系列运载火箭的工作范围扩大到了能覆盖包括太阳同步轨道的全部地球轨道。 长征四号运载火箭是在改进长征三号运载火箭一、二级的基础上,新研制第三级而发展起来的。它在继承已有技术成果的同时,采用了不少先进的技术措施。控制系统采用数字式网络、数字式调零方案和双向伺服机构,三级推进系统采用定压全程氦气增压系统和主、副增压管路方案,三级发动机采用铌合金喷管延伸段,姿控发动机系统采用表面张力贮箱,三级贮箱采用高强度铝单层薄壁共底结构等。这些新技术在长征四号运载火箭上都得到了成功应用。 长征四号运载火箭自投入使用以来,两次发射风云一号气象卫星均获圆满成功,已经成为中国长征系列运载火箭中的多用途运载工具。 本文着重介绍了长征四号运载火箭性能优良、用途广泛、可靠性高、经济性好等主要特点,展望了其良好的发展前景。

Long March-4 is a member of China's Long March launch vehicle family, in 1988, its first launching achieved a perfect success, thus ex-panding the mission coverage of Long March family to all kinds of earth or-bits including sun-synchronous orbit.Long March-4 was developed on the basis of the first and second stages of Long March-3 with a newly deve-loped third stage. While the available achievements being inherited, many advanced technical measures were adopted successfulty on Long March-4. For examples, the digital network, the digital zero adjusting scheme and the two-axes gimbaling mechanism were adopted in the con-trol system; a constant pressure helium full-duration primary / se-condary two-way pressurization scheme was used in the third stage propulsion system; a columbium noz-zle extention was incorporated in the third stage engine; the surface tension propellant tank was used in the atti-tude control engine system and a high strength aluminium single-thin-layer common intertank bulkhead tankage design was adopted, etc.Long March-4 can be also equipped with the adaptor for secon-dary payload, so that it can be used for multiple satellites with one launcher. In 1990, on its second launching, Long March-4 success-fully sent China's second meteorolo-gical satellite FY-1 and two piggyback balloon satellites Atmos-phere-1 into designed orbits. Hence, Long March-4 has become a multiple-function carrier.In this paper, the author des-cribes the main features of Long March-4 with the emphasis on its good performance, multiple usage, high reliability and favorable cost effectiveness, and predicts the bright prospect in its further evolution.