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1.
美国海军装备的F-14“雄猫”舰载多用途战斗机9月22日已正式退出现役。替代它的是最新型的F/A-18E/F“超级大黄蜂”战斗机。此外,美国空军现役的2000多架F-16战斗机很快就将到达退役年限。未来美军将用F-35战斗机逐渐取而代之。一时间,这些目前被认为仍然先进的战机的最后归宿引起了人们的关注。它们会就此退出历史舞台吗?  相似文献   

2.
令人失望的战斗机 除了进气道外型一改再改,其电子系统总存在电磁不兼容的问题.同时机体还不断发生结构问题,美国空军至1969年时已损失15架F-111,经过详细检查发现,F-111翼箱结构有严重裂缝.所有已装备的223架立即停飞进行全面检查,澳在利亚空军的F-111C甚至在美国封存待修、直到更换翼箱解决结构问题后,才恢复交机。  相似文献   

3.
F-5E/F“虎”Ⅱ式战斗机在20世纪70年代成为美国对其第三世界盟国进行军火倾销有主力机种,由于该机经历过实战考验并承袭有前一代F-5A/B“自由战士”战斗机维护方便等特点,使其在问世后的10年内,被销售至全球21个国家和地区。并因此在国际军火交易中形成法国“幻影”Ⅲ、前苏联MiG-21以及F-5E/F三种机型鼎立的局面。  相似文献   

4.
在这次“自由伊拉克”行动中,有两种美国首次投入实战的武器,第一种F/A-10E/F战斗机,另一种则是被称为“炸弹之舟”的MOAB。  相似文献   

5.
美军以F/A-18F战斗机换装F-14系列战斗机正进入紧锣密鼓的阶段。在第一个实战中队F/A-18E配属于第14舰载机联队后第一个替换F-14战斗机的VFA-41中队也已经随着与尼米兹(USS Nimitz.CVN 68)号搭配的第11舰载机联队(NH)于2003年“自由伊拉克”战役中,千波斯湾执行首次实战部署。而随着换装中队的逐渐增多F-14系列战斗机正加速退出太平洋舰队舰载机联队。太平洋地区最后一个F-14A中队.第5舰载机联队的VF-154中队已经于9月24日飞返美国。  相似文献   

6.
美国雷锡恩公司正式重新启动了AGM65E2/L激光制导型小牛导弹的生产工作。在重启生产之前,美国空军和海军开展了一项研发测试/1乍战使用测试项目,总共用F-16、A-10、F/A-18和AV-8B等飞机平台测试了15枚激光制导型小牛导弹,分别对静止目标和运动目标实施打击。  相似文献   

7.
F-111是世界上第一种实用化的可变后掠翼战机(Variable-Geometry wing),大概也是有史以来在发展过程上最受争议的飞机之一。这一切都要从20世纪60年代开始说起。那时美国空军计划发展一种全能型战斗机,要求该机拥有战斗机的速度、轰炸机的有效载荷、以及运输机的航程,结果发展出来的是一架重达100吨的庞然巨物。  相似文献   

8.
F-5A/B“自由战士”战斗机在全球成功的行销策略.使得诺斯罗普厂在五角大楼的授意下.继续研发上述机种的衍生型.以便继续占有原使用国的市场。依据美国空军器材的部件和批号的概念.诺斯罗普厂决定开发的“自由战士”后继机型.不仅须有较高的后勤维护通用性.更要在发动机推力与武器能力上取得“跨世纪的性能跃升.同时,也将新机设定成足以应对前苏联MiG-21“鱼窝”(Fishbed)的高性能战术战斗机。基于以上前提”虎”Ⅱ式战斗机应运而生.并在1969年3月F-5E的原型机进行了首航试飞。  相似文献   

9.
美国空军即将为现役的F-16、F-15及A-10机群配备新型的“狙击手”(Sniper XR)先进光电标定吊舱,这种新的光电标定吊舱是由洛马导弹与火控公司(LM-MFC)生产,美国空军已经订购92台“狙击手”吊舱,目前已经交付30台,而未来美国空军还计划再追加采购522台“狙击手”光电标定吊舱供麾下机群使用,这笔采购的总金额为8亿4300万美元。  相似文献   

10.
F-14A1971年.格鲁曼的F-14A参与了美国空军IMI计划的竞争。IMI(改进型有人驾驶截击机)计划旨在寻找康维尔F-106的后继机。为了提高航程.空军型F-14A在机腹安装了巨大的保形油箱.并可以附加四个副油箱以提高航程。F-14A符合IMI大多数的性能要求。为了向军方展示.格鲁曼将303E的全尺寸木模改成空军型。  相似文献   

11.
Through concurrently measurements by Communication/Navigation Outage Forecasting System (C/NOFS), Sanya VHF radar and GPS ionospheric scintillation receiver on 12 March 2010, five plasma bubbles were found and three of them were observed by all those instruments. Two well-developed plumes with strong backscatter echoes were measured by Sanya radar and their corresponding depletions were observed by C/NOFS in Orbit 10317, 10318 and 10319. Broad plasma depletions resulting from merging process were found in orbit of 10318. The occurrence time and geophysical positions of scintillations correlate well with observations implemented by Sanya VHF radar and C/NOFS. Observations from three types of instrument indicate that the spread F irregularities have distinct scale. There were longitudinal differences between Sanya VHF radar and C/NOFS as irregularities measured, and the eastward drift of developed bubbles are responsible for these differences.  相似文献   

12.
F2层对地磁扰动的响应   总被引:3,自引:1,他引:2  
利用37个电离层垂直探测站1974-1986年的数据,采用f0F2与地磁ap指数相关分析的方法,首次得到一个太阳活动周期各年东亚-澳大利亚扇区,欧洲-非洲扇区和美洲-东太平洋扇区F2层对地磁扰动响应随地磁纬度的分布.结果指出,地磁高纬和中纬地区为负响应,低纬和赤道地区为正响应,大约在±30°附近换向.最大正响应在磁赤道附近,最大负响应在地磁纬度±50°附近,最大负响应的幅度大于最大正响应的幅度.存在明显的经度差别和南北半球不对称性.  相似文献   

13.
A study of the critical frequency foF2 variations after the large earthquake (Ms = 8.1) which occurred on 29 September, 2009 in the region of Samoa Islands in the Pacific Ocean is carried out using data of the ionospheric station of Kwajalein. The epicenter of the earthquake was located at about 184 km southwest from Apia (the capital of West Samoa). It was found that wave-like perturbations of foF2 were observed for ∼3 h above the station (located approximately 3560 km northwest from the epicenter). The amplitude of the disturbance was as large as ∼20% of the average magnetic quiet day foF2 values. A comparison of the observed perturbations of foF2 with the ones detected at Stanford ionospheric station after the Alaska earthquake of 28 March 1964 (Ms = 8.4) showed a close similarity of the wave-like perturbations of foF2 in both cases.  相似文献   

14.
The occurrence of mid-latitude spread F (SF) over South Africa has not been extensively studied since the installation of the DPS-4 digisondes in 1996 and 2000 at Grahamstown (33.32 °S, 26.50 °E) and Madimbo (22.38 °S, 30.88 °E) respectively. This study is intended to quantify the probability of occurrence of F region disturbances associated with SF over South Africa. A study was conducted using data for 8 years (2001–2008) over Madimbo (with a time resolution of 30 min) and Grahamstown (with a variable time resolution of 15 and 30 min). In this study, SF has been classified into frequency SF (FSF), range SF (RSF) and mixed SF (MSF). The SF events were identified by manually identifying ionograms showing SF and tabulating them according to type for further statistical analysis. The results show that the diurnal pattern of SF peaks strongly between 01:00 and 02:00 local time, LT (LT = UT + 2 h), where UT is the universal time. This pattern is true for all seasons and types of SF at Madimbo and Grahamstown in 2001 and 2005, except for RSF which had peaks during autumn and spring in 2001 at Madimbo. The probability of both MSF and FSF tends to increase with decreasing solar activity, with a peak in 2005 (a moderate solar activity period). The seasonal peaks of MSF and FSF are more frequent during winter months at both Madimbo and Grahamstown. In this study, SF was evident in ∼0.03% and ∼0.06% of the available ionograms at Madimbo and Grahamstown respectively during the 8 years.  相似文献   

15.
16.
Since modern digital ionosondes and minicomputers are now generally accessible there is no justification any more for using inversion schemes in which the influence of the magnetic field is ignored or a monotonous profile is assumed so that the regular presence of valleys is neglected. Therefore inversion schemes like POLAN and ARTIST should at least be applied.

We propose a new global and analytical representation of the F2-layer profiles which is found to be helpful for specific ionospheric situations.  相似文献   


17.
提出了一种基于F偏差代表点的高斯过程矩匹配滤波方法。该方法通过高斯过程学习系统的过程函数和观测函数,在高斯矩匹配滤波的框架下利用F偏差代表点进行数值计算。在单变量非线性模型及静基座初始对准中进行的仿真实验表明,该方法的精度不低于解析计算的高斯过程假设密度滤波(GP-ADF),远高于高斯过程无迹卡尔曼滤波(GP-UKF)。  相似文献   

18.
利用Aureol-3卫星在电离层F层高度上(650km左右)对电离层电场扰动与电子密度扰动的观测进行分析处理,在高纬电离层F层高度上可以检测到舒曼共振现象。根据等离子体参数,可以认为,发生在这个高度上的舒曼共振现象与L模式的波传播有关,舒曼共振的基频是与电子密度的大尺度不规则性有关,谐波分量与正向密度梯度相关。  相似文献   

19.
本文从等离子体二流体方程组出发,导出适于描述晚间赤道F层现象的DFA模型。证明该模型存在大量偶极涡解。它们可望用于解释赤道扩展F过渡区和中小尺度两区域内存在的大量密度不规则体事实。   相似文献   

20.
This paper presents the results of modeling the ionospheric effect of the seismogenic electrostatic field (SEF) seen at the earth’s surface as a perturbation of the vertical atmospheric electrostatic field in the earthquake preparation zone. The SEF distribution at ionospheric altitudes is obtained as an analytical solution of the continuity equation for the electric current density. It is shown that at night, the horizontally large scale SEF can efficiently penetrate into the ionosphere and produce noticeable changes in the horizontal distribution of the F region electron density. The results suggest that the seismogenic electrostatic field could be a possible source for the ionospheric variations observed over Taiwan before the strong Chi Chi earthquake of September 21, 1999.  相似文献   

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