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The general assembly of the Lixun-1 upper stage Photo: Courtesy of CAS Space
    The general assembly of the Lixun-1 upper stage Photo: Courtesy of CAS Space
The Lixun-1 upper stage Photo: Courtesy of CAS Space
    The Lixun-1 upper stage Photo: Courtesy of CAS Space
Lixun-1 upper stage, a versatile "space tug" developed by China's commercial space firm CAS Space, is scheduled to make its maiden flight in the first quarter of 2027 after completing a series of key propulsion-system tests, the developer and its chief designer told the Global Times on Tuesday.
The "tug" is designed to ferry satellites from one orbit to another and support missions ranging from constellation deployment to lunar exploration. 
While the main stages of a rocket carry payloads from the ground into an initial orbit, an upper stage takes over once the craft is in space. By repeatedly restarting its engine and changing orbit, Lixun-1 can deliver satellites to higher or different orbits, distribute multiple spacecraft to separate destinations during a single launch, or send probes onto trajectories toward the moon and beyond, Global Times learned from the developer.
Yang Haoliang, chief designer of the Lixun-1 upper stage, compared the system to a shuttle service. "If the regular stages of a launch vehicle are like a long-distance bus," - they carry the upper stage and satellites from Earth to a near-Earth parking orbit - the upper stage then takes over as a "space tug," carrying its satellite "passengers" onward to their designated orbital "stops," Yang explained. 
That capability can have a direct impact on how efficiently satellites are launched and operated, Yang said. If a satellite has to climb from an initial orbit to its final destination using its own engine, the process can consume a considerable amount of onboard propellant and reduce the fuel available during its operational life. An upper stage can instead perform that orbital transfer, helping conserve satellite fuel and potentially extend its service life.
It can also make one rocket launch do more work. Instead of releasing a batch of satellites into roughly the same orbit, Lixun-1 can repeatedly ignite its engine and maneuver between deployments, sending different satellites to different altitudes and inclinations. Yang said this would help accelerate constellation deployment while improving the efficiency of individual launches.
The practical ambitions behind the system are backed by a major technical milestone reached this month. In August, Lixun-1 completed its PV-001 integrated propulsion-system coordination firing test, during which the entire system operated smoothly for 566 seconds.  
Yang told the Global Times that the current Lixun-1 upper stage has a thrust of 20 kilonewtons and can achieve a specific impulse of 315 seconds, which he described as reaching an internationally leading level. The August firing covered the planned profile for the maiden mission, an important step before the system proceeds to flight testing.
The test was more than a demonstration of the engine itself. As an important system-level verification during development, it examined the coordination and engineering reliability of the engine pressurization system, propellant delivery system, propellant management system and servo-control system under the fully integrated configuration.
Of a series of tests that accumulated 5,211 seconds of firing time, the latest one focused on three core technologies: a high-thrust, high-performance 20-kilonewton upper-stage engine capable of multiple starts; balanced propellant delivery from multiple parallel tanks; and a highly reliable integrated electrical system. Their successful verification means Lixun-1 has completed its system-level testing and is ready to move into the flight-test phase, according to the developer.
Lixun-1 has been designed as a modular and generally adaptable upper stage rather than a system tied to only one rocket. It is intended to work with CAS Space's Kinetica-2 and Kinetica-2 heavy-lift variants as well as other launch vehicles, Yang said.
When paired with the Kinetica-2 family, Lixun-1 could significantly expand the rocket's mission range. For communications missions, it could deliver satellites to geosynchronous transfer orbit or even directly to geosynchronous orbit, conserving satellite propellant while supporting the deployment of high-throughput satellites and future 6G communications spacecraft.
For multi-satellite missions, the combination could distribute spacecraft to different orbital altitudes and inclinations during a single launch, potentially serving both low-Earth-orbit constellations and medium- or high-orbit payloads. For deep-space missions, it could place probes onto Earth-moon transfer trajectories and support lunar exploration, Yang said.
The upper stage is designed to be able to conduct more than 20 engine ignitions, autonomously plan orbital-transfer routes and operate under the vacuum and extreme temperature conditions of space. After completing payload deployment, it can also carry out orbital disposal maneuvers to reduce space-debris risks.
Yang said the Lixun-1 and Kinetica-2 combination is designed to cover the vast majority of commercial satellite launch requirements while retaining the ability to participate in major national space projects. More broadly, the upper stage forms part of CAS Space's effort to build launch capabilities reaching medium and high Earth orbits and deep space, extending the reach of China's commercial space sector toward higher orbits and more distant destinations.
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美国海军海上系统司令部近日宣布,美国海军“星座”级护卫舰首舰已在意大利芬坎蒂尼集团旗下的马里内特造船厂开工建造,预计2026年交付。

二 | 美海军“星座”级护卫舰性能如何?美国为何时隔多年重新开建护卫舰? 就相关话题,军事观察员周伟政 深入解析。“星座”级护卫舰是美海军最新一代护卫舰,该型舰舰长约150米,宽约19米,满载排水量7000吨左右,最高航速超26节。军事观察员周伟政认为,“星座”级护卫舰设计中规中矩,性能务实。周伟政: “星座”级护卫舰放弃了此前追求的“科幻”“超前”路线,显得更加务实。该型舰艇吨位较大,自持力和适航性强,适合远洋部署,防空反导能力突出,且具有较大改装潜力。由于采用了大量成熟技术装备,设计风险小,“星座”级护卫舰能够被以较快的速度批量建造。据了解,美国从上世纪90年代开始,逐步减少护卫舰的数量。自从最后一艘“佩里”级护卫舰退役至今,美国已近十年没有护卫舰了。军事观察员周伟政分析,美国重新批量建造护卫舰与其强力推行“大国竞争”战略密切相关。周伟政:美国停止建造和使用护卫舰是因为冷战后,美国海军自认为,已没有能与之抗衡的海上力量了。 美国的军事战略从“争夺制海权”转变为“由海制陆”“前沿存在”,重点打造偏重于对陆打击的“朱姆沃尔特”级驱逐舰以及濒海战斗舰。美国重新开建新护卫舰,最根本的原因是美国军事战略、海军战略再次转型,要打所谓的“大国高端战争”,与地区强国争夺制海权。 加上美国到处推行所谓“航行自由”“军事存在”,迫切需要新型护卫舰承担低烈度条件下的常规任务。据报道,美海军计划总共建造20艘“星座”级护卫舰。军事观察员周伟政分析,美国加紧全球海上扩张但力有不逮,批量建造“星座”级护卫舰就是为了避免老旧舰艇退役后美海军面临“无舰可用”的尴尬。周伟政:由于面临多型舰艇逐步退出现役的状况,美国海军计划采购20艘“星座”级护卫舰,与下一代万吨级DDG(X)驱逐舰配套,作为航母编队的属舰, 承担编队防空反潜任务,同时也可能会以单舰或小编队形式,前往热点区域,承担军演、护航、巡逻等任务。军事观察周伟政指出,由于资金难保障和建造能力不足,“星座”级护卫舰能否如期完成批量建造计划,还存在很大不确定性。周伟政:美国计划一口气建造多艘新型护卫舰,难度比较大。

三 | 一方面,“星座”级护卫舰单舰造价高达16亿美元,一下子采购20艘,美国国会愿不愿意拨款很难说。

四 | 另一方面,美国造船厂的能力早已经不复当年,建造新舰的速度赶不上老舰退役的速度,而且造船厂的产能也不是单靠财政拨款就能短期内提升的。

五 | 如此看来,美国海军的造舰计划,面临很大的不确定性。

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Published on:15:37:18


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