阿波罗登月舱
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阿波罗登月舱（Apollo Lunar Module）是阿波罗宇宙飞船登月直接登月的部分，由美国的阿波罗计划为达到登月并成功返回而建。登月舱又被其制造商称作“LM”（月面模块），也叫做“LEM”（登月模块）。 登月舱的设计目标是在6.65米³的空间内容纳两名宇航员。登月舱共6.4米高，4.3米宽，有四个支撑脚。登月舱由上升级和下降级组成；登月舱的总质量，以降落部分(10,334千克)为主，达15,264千克。
[编辑] 历史选择阿波罗登月舱的原因是因为国家航空航天局决定采用月球轨道集合方案（LOR），而不是月面直接起飞方案或者地球轨道集合方案（EOR）（其他对接集合方案参见选择任务模式）。直接起飞方案和地球轨道集合方案都将整个阿波罗飞船降落在月球上；在决定使用月球轨道集合方案之后，就有必要制造一艘可到达月面的独立飞船。 登月舱的生产合同由格鲁曼飞机工程公司获得，还有一些转包商。格鲁曼公司从50年代末就开始研究空间对接，并在1962年重新开始此项研究。1962年7月，有11家公司应邀为登月舱进行投标。到同年9月时，9家公司提交了标书，格鲁曼公司在同月最终赢得了合同。预计合同额为3.5亿美元。最开始有4家分包商：贝尔航空系统（上升级发动机）、哈密尔顿标准公司（环境控制系统）、马夸特（反作用力控制系统）和火箭达因（下降级发动机）。 登月舱上的基本导航、飞行与控制系统（PGNCS）是由麻省理工大学仪表实验室开发的。导航计算机是由雷瑟奥恩公司制造。在指令舱中有一部与之类似的导航系统。备用的任务中止导航系统（AGS）是由TRW开发的。 To learn lunar landing techniques, astronauts practiced in the Lunar Landing Research Vehicle (LLRV), a flying vehicle that simulated the Lunar Module on earth. A 200'-tall, 400'-long gantry structure was constructed at NASA Langley Research Center; the LLRV was suspended in this structure from a crane, and "piloted" by moving the crane. (The facility is now known as the Impact Dynamics Research Facility, and is used for aircraft crash tests.) Configuration freeze did not start until April 1963 when the ascent and descent engine design was decided. In addition to Rocketdyne a parallel program for the descent engine was ordered from Space Technology Laboratories in July 1963, and by January 1965 the Rocketdyne contract was cancelled. As the program continued there were numerous redesigns to save weight (including 'Operation Scrape'), improve safety, and fix problems. For example initially the module was to be powered by fuel cells, built by Pratt and Whitney but in March 1965 they were paid off in favor of an all battery design. The initial design iteration had the LEM with three landing legs. It was felt that three legs, though the lightest configuration, was the least stable if one of the legs were damaged during landing. The next landing gear design iteration had five legs and was the most stable configuration for landing on an unknown terrain. That configuration was too heavy and the compromise was four landing legs. 1968年1月22日，登月舱首次由土星IB火箭发射升空，此次无人发射的目的是对推进系统进行轨道测试。The first LM flight was on January 22, 1968 when the unmanned LM-1 was launched on a Saturn IB for testing of propulsion systems in orbit. The next LM flight was aboard Apollo 9 using LM-3 on March 3, 1969 as a manned flight (McDivitt, Scott and Schweickart) to test a number of systems in Earth orbit including LM and CSM crew transit, LM propulsion, separation and docking. Apollo 10, which launched on May 18, 1969, was another series of tests, this time in lunar orbit with the LM separating and descending to within 10 km of the surface. From the successful tests the LM successfully descended and ascended from the lunar surface with Apollo 11. 1970年4月，登月舱水瓶座号在阿波罗13号任务中意外的扮演了挽救三名宇航员（指令长小詹姆斯·洛威尔、指令/服务舱飞行员约翰·斯威格特和登月舱飞行员弗莱德·海斯）的角色。在由电路短路引起的指令舱氧气罐过热并爆炸后，水瓶座号便开始作为救生船一直到返回地球轨道，期间水瓶座号的电池还为指令舱上至关重要的返回电池充电以确保宇航员可以在1970年4月17日进入大气层并安全溅落。登月舱上的下降发动机本来是用来在下降至月面时减速用的，但在阿波罗13号任务中却被用来在绕月飞行时加速飞船以进入返回航线。阿波罗13号事故中登月舱系统共为3名宇航员提供了90小时的生命保障，而它的设计能力只是2名宇航员，45小时。（详见阿波罗13号）。 [编辑] 登月舱规格登月舱中的下降级中包括了登月装备、雷达天线、降落火箭引擎、以及降落所需的燃料。下降级上还带有几个装载其他货物的隔间，比如阿波罗月面实验包、移动仪器推车（阿波罗14号）、月球车（阿波罗15号、阿波罗16号和阿波罗17号）、月面摄像机、月面工具和月面样品采集箱。 而且登月纪念牌也安装在下降级的爬梯上。 起飞部分包括舱盖、反应控制系统、雷达和通信天线、起飞火箭引擎以及回到月球轨道并与指令/服务舱对接所需的燃料。
上升级发动机的推力在地球上小于重力，但在月球上足够将上升级送入月球轨道。
[编辑] 生产的登月舱
[编辑] 登月卡车阿波罗登月卡车是一个不载人的单独的下降级，其设计荷载为5公吨。阿波罗卡车的设计目的是向永久月球基地输送器材和给养，但实际上一直到现在也从未建立一个月球基地。最早设想的方案是：由土星5号火箭将阿波罗卡车和一整组阿波罗宇航员一起送入月球轨道，并将阿波罗卡车引导着降落在基地附近，再由月球基地上的宇航员把货物卸下“卡车”，最后送货的宇航员返回地球。 [编辑] 科幻中的登月舱在肖恩·约翰逊的小说冰中，出现过以登月舱和登月卡车为原型的飞船，小说描写了一次想象中的阿波罗19号悲剧：登月卡车由土星IB运载火箭运往月球并在预订降落场降落，之后执行J任务的阿波罗宇航员驾驶传统的登月舱精准的降落在登月卡车附近 （让人想起皮特·康拉德在阿波罗12号任务中的降落），之后登月舱LM-13号的上升级引擎发生故障而无法点燃，最终把2名宇航员困在月球上——事实上在阿波罗计划中从来没发生过这样的事。 [编辑] 后继者The LM design was later incorporated into the Apollo Telescope Mount on the successful Skylab space station. Originally planned to be launched on an unmanned Saturn 1B rocket, similar to the unmanned Apollo 5 test flight, NASA decided to save costs and launch the ATM with the station itself. This decision saved the station, as the ATM's "windmill" solar panels helped keep the station operation after its surviving solar panel on the station was damaged during launch (the other was ripped off). In 2005, NASA announced that the successor to the Space Shuttle, the Crew Exploration Vehicle, would feature, for its lunar landing missions, a Lunar Surface Access Module (LSAM) which is roughly based on the Apollo LM. Like the LM, it has a descent and ascent module (the latter to house the crew), but unlike the LM, it would be powered by liquid hydrogen (LH2) and liquid oxygen (LO2) for the landing phase, and by liquid methane (LCH4) and LOX for the ascension phase. The major difference between the LSAM and the LM is that the LSAM would be launched separately into a Low Earth Orbit atop of the Shuttle Derived Launch Vehicle's Heavy Lift booster, with the manned CEV being launched separately atop of the Crew Launch Vehicle. Both vehicles would dock into Low Earth Orbit similar to the Earth Orbit Rendezvous plan in Apollo's early stages. [编辑] 外部链接
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