《航空周刊120131》中国歼20隐性战斗机 向前进，进，进 ...

《航空周刊120131》中国歼20隐性战斗机 向前进，进，进，进。。。
Chinese J-20 Stealth Fighter Advances
http://www.aviationweek.com/aw/g ... amp;channel=defense
Jan 31, 2012
By Bill Sweetman Washington


Every indication is that nobody in Western intelligence saw the Chengdu J-20 coming. While it was known that China was developing a stealthy combat aircraft, the J-20 has emerged earlier than expected and appears to be more mature than the X‑plane or demonstrator that many people anticipated.

The debut of the J-20 had been predicted in a November 2009 interview on Chinese television by Gen. He Weirong, deputy commander of the People’s Liberation Army Air Force. The general said at the time that a “fourth-generation” fighter would be flown in 2010-11 and be operational in 2017-19.

At least two J-20 prototypes were complete by the time the aircraft made its first flight—or at least its first public flight—on Jan. 11, 2011. The two aircraft are distinguished by the detail design of their exhaust nozzles, leading to speculation that one of the aircraft has Russian-supplied AL-31F engines, of the type fitted to the Chengdu J-10, and the other has the Chinese-developed WS-10 engine.

The J-20 is a big aircraft. Although its overall length (around 66 ft.) is not much greater than that of the 62-ft. Lockheed Martin F-22, the main structure from nose to exhaust nozzles is considerably longer. Like the F-22, it has large weapon bays in the lower fuselage and smaller side bays, the latter probably dedicated to air-to-air missiles.

The J-20 echoes the canard configuration of the J-10, but with canards level with, and immediately in front of, the wing. Two small, canted, all-moving vertical stabilizers are fitted. Although no U.S. manned stealth aircraft have flown with canards, a tail-first layout was featured by early Joint Strike Fighter designs, including Lockheed Martin’s—which the J-20 resembles—and McDonnell Douglas’ X-36 unmanned demonstrator.

Stealth design features mostly follow Lockheed Martin F-22 and X-35 practice. A high chine line around the forebody continues through the inlets and upper body, and flat, canted side surfaces blend into a flat underside via a small-radius edge. The canopy shape is also reminiscent of the F-22. The J-20 uses a diverterless supersonic inlet (DSI)—originally developed by Lockheed Martin, DSI technology is now used on the J‑10B, JF-17 and (according to one report) the Saab Gripen JAS 39E/F.

The rear-aspect view of the aircraft is not as stealthy, a feature also seen on the Sukhoi T-50. This is clearly an intentional trade, eliminating the heavy 2D nozzles of the F-22. In this respect, both the T-50 and J-20 reflect the philosophy behind the pre-1986 Advanced Tactical Fighter studies that preceded the F-22, based on the theory that a fast, high-flying, agile aircraft is relatively immune from rear-quarter attacks.

According to a Chinese paper released on the Internet, the main goal of the design was to achieve high speed and maneuverability with the engines that would be available to China in the near future—the AL-31F and WS-10—which do not have the same thrust/weight ratio as the latest Western engines. This resulted in the selection of a delta wing and relatively long body for low supersonic drag, plus large, high-deflection canards to provide agility. The all-moving vertical tails are said to be 40% smaller than conventional fin/rudder designs, and accordingly lighter. Supercruise is probably not attainable with existing engines, but the design looks capable of it, once propulsion technology in China improves.

In 2012, China-watchers will be monitoring progress with the flight-test program and looking for signs of work on the many challenging aspects of stealth. A stealth fighter needs multispectral, active and passive sensors to detect and track its targets, and those sensors need to be fused and managed to minimize emissions. Similarly, to operate at maximum effectiveness as part of a networked force, stealth aircraft need effective low-probability-of-intercept voice and data communication systems. These are problems that the U.S. is still wrestling with, after 25 years of work.

There is another, more fundamental question: What is the J-20 for? The fighter is large for air combat—but China, simply because of geographical factors, doesn’t face an adversary fighter force of the kind that the F-22 was designed to counter. At the same time, the J-20 weapon bays are not large enough for most standoff air-to-surface weapons. One possibility is that the J-20 is intended to threaten intelligence, surveillance and reconnaissance assets and tankers, by using stealth and speed to defeat their escorts.

---

http://mil.huanqiu.com/weapon/2012-02/2398193.html
据《航空周刊》1月31日报道，一切迹象都表明，西方情报机构没有能够提前预见到成都歼-20飞机的亮相。尽管，中国正在研发隐形战斗机的这一事实是周所周知的；但是，歼-20的出现却远比大家估计的早。而且，歼-20的表现也比人们所预期的隐形战机性能更加成熟。

　　美刊称，在2009年11月份，中国电视节目对人民解放军空军副司令员何为荣将军的一次采访中，歼-20战机首次被公众得知。何将军在该次采访中曾经推测，第四代战斗机应该会在2010-2011年期间进入试飞阶段；并且将在2017-2019年期间正式投入使用。截止到2011年1月11日歼-20飞机第一次试飞，或者说第一次公开试飞时为止，中国至少已经完成了两架歼-20战机原型机。这两架飞机在排气喷嘴的细节设计上还有一定区别；所以外界预测，这两架飞机的其中一架可能采用了与歼-10战机一样的由俄罗斯提供的AL-31F型引擎；而另外一架则采用了由中国自主研发的WS-10型引擎。

　　美刊称，歼-20称得上是一架大飞机。尽管它的整体长度（接近66英尺）比洛克希德-马丁公司研制、长度为62英尺的F-22长出并不太多；但它从机头到排气喷嘴部位的主体结构显然要比F-22长一些。歼-20的弹仓设计很接近F-22，位于机身下部的武器托架相对较大；而侧托架则相对要小一些，据推测应该是用来装载空对空导弹。在歼-20正式出现之前，关于它将采用的气动布局就谣言四起；但是，设计最终还是延续了歼-10的鸭式气动布局。同时，位于机尾的两个小的、倾斜的、可以全方位移动的垂尾非常合适其整体设计。尽管，美国当前拥有的隐形战机中没有采用鸭式气动布局的机型；但根据其早期提出的联合打击战斗机设计方案，他们在该方案中计划建造的飞机采用的正是水平尾翼前置的鸭式气动布局；其中就包括了与歼-20十分相像的-F22，以及道格拉斯推出的X-36型无人机。

　　美刊称，隐形飞机的设计方案一般都遵循洛-马公司的F-22战机，以及X-35战机的做法；进气道和机身上部之间被设计成一个高折角，而平坦而倾斜侧面则通过一个小半径的弧度转入平坦的底面。如果从上往下看，歼-20的机身整体呈树冠形状，这也让人联想起F-22。歼-20上还采用了最初由洛-马研制出来的无附面层隔道超音速进气道（diverterless supersonic inlet，DSI）；到目前为止，DSI技术已经被应用在歼-10B、JF-17，以及瑞典SAAB公司设计的“鹰狮战机”JAS-39E/F等机型上。从飞机的尾部看起来，歼-20并不像上述提及的那些隐形飞机；这个造型反而和俄罗斯苏霍伊公司的T-50飞机类似。这样做显然是有目的的，应该是为了避免采用像F-22一样沉重的二维喷嘴。在这个方面，无论是T-50还是歼-20，都体现了从1986年以前直到F-22推出之前这一阶段内，进行的先进战术战斗机研究( Advanced Tactical Fighter studies)中提出的理论。根据这个理论，快速、高飞行高度、足够敏捷的飞机对来自后方的攻击拥有较高的免疫力。

　　美刊称，而根据在网上流传的一篇中国论文中的内容，这样设计的主要目的是为了保证歼-20在使用中国当前拥有的，例如AL-31F和WS-10这样的引擎时，也能够获得高的速度和好的机动性；而这样的引擎在推力/重量比上还不能和西方国家现有的引擎相提并论。歼-20战机选择采用三角翼，又采用相对较长的机身来解决低超音速动力的问题；再加上既大且高的偏转鸭翼，这样的设计能让它拥有更好的敏捷性。在全动垂尾的设计上，据称歼-20比传统的垂直安定面和方向舵面积设计要小40%，而且更加轻便。尽管，采用现有的引擎让其巡航能力并不值得称道；但在气动方面的设计还是很不错的。假如中国能在动力技术方面取得新的进展，这个瑕疵就能被很好的弥补。

　　2012年，中国观察家们将会继续关注歼-20的飞行测试项目的进展；同时，还将不断寻找中国在隐形战机技术领域，针对现有技术挑战开展工作的迹象。一架隐形飞机为了探测和追踪它的目标，需要在飞机上装备多种基于多种光谱原理、主动或者被动的传感器；并且需要对从这些传感器获得的数据信息进行充分融合和管理，从而给飞行员提供最简洁直观的可靠数据。类似的，为了让隐形战机作为网络化力量中的一部分，发挥它的最大效率；隐形战机需要一个高效率，低几率被拦截的噪声和数据通讯系统。为了攻克这些问题，美国付出了25年的努力；但是到目前为止，仍然没有寻得很好的解决方案。

　　美刊称，还有另外一个更加基础的问题：歼-20的设计初衷是什么？对空中战斗来说，歼-20作用很大；但是鉴于中国的地理环境因素，他们并不需要面对像F-22被设计用来对抗的那些敌对战机力量。与此同时，歼-20的武器托架太小，不足以装下大部分当前的空对地对抗武器。关于设计初衷有一种可能，也许歼-20的目标是威慑情报、监视、侦察，通过隐形的特性和速度上的优势对护航力量进行打击。
《航空周刊120131》中国歼20隐性战斗机 向前进，进，进，进。。。
Chinese J-20 Stealth Fighter Advances
http://www.aviationweek.com/aw/g ... amp;channel=defense
Jan 31, 2012
By Bill Sweetman Washington


Every indication is that nobody in Western intelligence saw the Chengdu J-20 coming. While it was known that China was developing a stealthy combat aircraft, the J-20 has emerged earlier than expected and appears to be more mature than the X‑plane or demonstrator that many people anticipated.

The debut of the J-20 had been predicted in a November 2009 interview on Chinese television by Gen. He Weirong, deputy commander of the People’s Liberation Army Air Force. The general said at the time that a “fourth-generation” fighter would be flown in 2010-11 and be operational in 2017-19.

At least two J-20 prototypes were complete by the time the aircraft made its first flight—or at least its first public flight—on Jan. 11, 2011. The two aircraft are distinguished by the detail design of their exhaust nozzles, leading to speculation that one of the aircraft has Russian-supplied AL-31F engines, of the type fitted to the Chengdu J-10, and the other has the Chinese-developed WS-10 engine.

The J-20 is a big aircraft. Although its overall length (around 66 ft.) is not much greater than that of the 62-ft. Lockheed Martin F-22, the main structure from nose to exhaust nozzles is considerably longer. Like the F-22, it has large weapon bays in the lower fuselage and smaller side bays, the latter probably dedicated to air-to-air missiles.

The J-20 echoes the canard configuration of the J-10, but with canards level with, and immediately in front of, the wing. Two small, canted, all-moving vertical stabilizers are fitted. Although no U.S. manned stealth aircraft have flown with canards, a tail-first layout was featured by early Joint Strike Fighter designs, including Lockheed Martin’s—which the J-20 resembles—and McDonnell Douglas’ X-36 unmanned demonstrator.

Stealth design features mostly follow Lockheed Martin F-22 and X-35 practice. A high chine line around the forebody continues through the inlets and upper body, and flat, canted side surfaces blend into a flat underside via a small-radius edge. The canopy shape is also reminiscent of the F-22. The J-20 uses a diverterless supersonic inlet (DSI)—originally developed by Lockheed Martin, DSI technology is now used on the J‑10B, JF-17 and (according to one report) the Saab Gripen JAS 39E/F.

The rear-aspect view of the aircraft is not as stealthy, a feature also seen on the Sukhoi T-50. This is clearly an intentional trade, eliminating the heavy 2D nozzles of the F-22. In this respect, both the T-50 and J-20 reflect the philosophy behind the pre-1986 Advanced Tactical Fighter studies that preceded the F-22, based on the theory that a fast, high-flying, agile aircraft is relatively immune from rear-quarter attacks.

According to a Chinese paper released on the Internet, the main goal of the design was to achieve high speed and maneuverability with the engines that would be available to China in the near future—the AL-31F and WS-10—which do not have the same thrust/weight ratio as the latest Western engines. This resulted in the selection of a delta wing and relatively long body for low supersonic drag, plus large, high-deflection canards to provide agility. The all-moving vertical tails are said to be 40% smaller than conventional fin/rudder designs, and accordingly lighter. Supercruise is probably not attainable with existing engines, but the design looks capable of it, once propulsion technology in China improves.

In 2012, China-watchers will be monitoring progress with the flight-test program and looking for signs of work on the many challenging aspects of stealth. A stealth fighter needs multispectral, active and passive sensors to detect and track its targets, and those sensors need to be fused and managed to minimize emissions. Similarly, to operate at maximum effectiveness as part of a networked force, stealth aircraft need effective low-probability-of-intercept voice and data communication systems. These are problems that the U.S. is still wrestling with, after 25 years of work.

There is another, more fundamental question: What is the J-20 for? The fighter is large for air combat—but China, simply because of geographical factors, doesn’t face an adversary fighter force of the kind that the F-22 was designed to counter. At the same time, the J-20 weapon bays are not large enough for most standoff air-to-surface weapons. One possibility is that the J-20 is intended to threaten intelligence, surveillance and reconnaissance assets and tankers, by using stealth and speed to defeat their escorts.

---

http://mil.huanqiu.com/weapon/2012-02/2398193.html
据《航空周刊》1月31日报道，一切迹象都表明，西方情报机构没有能够提前预见到成都歼-20飞机的亮相。尽管，中国正在研发隐形战斗机的这一事实是周所周知的；但是，歼-20的出现却远比大家估计的早。而且，歼-20的表现也比人们所预期的隐形战机性能更加成熟。

　　美刊称，在2009年11月份，中国电视节目对人民解放军空军副司令员何为荣将军的一次采访中，歼-20战机首次被公众得知。何将军在该次采访中曾经推测，第四代战斗机应该会在2010-2011年期间进入试飞阶段；并且将在2017-2019年期间正式投入使用。截止到2011年1月11日歼-20飞机第一次试飞，或者说第一次公开试飞时为止，中国至少已经完成了两架歼-20战机原型机。这两架飞机在排气喷嘴的细节设计上还有一定区别；所以外界预测，这两架飞机的其中一架可能采用了与歼-10战机一样的由俄罗斯提供的AL-31F型引擎；而另外一架则采用了由中国自主研发的WS-10型引擎。

　　美刊称，歼-20称得上是一架大飞机。尽管它的整体长度（接近66英尺）比洛克希德-马丁公司研制、长度为62英尺的F-22长出并不太多；但它从机头到排气喷嘴部位的主体结构显然要比F-22长一些。歼-20的弹仓设计很接近F-22，位于机身下部的武器托架相对较大；而侧托架则相对要小一些，据推测应该是用来装载空对空导弹。在歼-20正式出现之前，关于它将采用的气动布局就谣言四起；但是，设计最终还是延续了歼-10的鸭式气动布局。同时，位于机尾的两个小的、倾斜的、可以全方位移动的垂尾非常合适其整体设计。尽管，美国当前拥有的隐形战机中没有采用鸭式气动布局的机型；但根据其早期提出的联合打击战斗机设计方案，他们在该方案中计划建造的飞机采用的正是水平尾翼前置的鸭式气动布局；其中就包括了与歼-20十分相像的-F22，以及道格拉斯推出的X-36型无人机。

　　美刊称，隐形飞机的设计方案一般都遵循洛-马公司的F-22战机，以及X-35战机的做法；进气道和机身上部之间被设计成一个高折角，而平坦而倾斜侧面则通过一个小半径的弧度转入平坦的底面。如果从上往下看，歼-20的机身整体呈树冠形状，这也让人联想起F-22。歼-20上还采用了最初由洛-马研制出来的无附面层隔道超音速进气道（diverterless supersonic inlet，DSI）；到目前为止，DSI技术已经被应用在歼-10B、JF-17，以及瑞典SAAB公司设计的“鹰狮战机”JAS-39E/F等机型上。从飞机的尾部看起来，歼-20并不像上述提及的那些隐形飞机；这个造型反而和俄罗斯苏霍伊公司的T-50飞机类似。这样做显然是有目的的，应该是为了避免采用像F-22一样沉重的二维喷嘴。在这个方面，无论是T-50还是歼-20，都体现了从1986年以前直到F-22推出之前这一阶段内，进行的先进战术战斗机研究( Advanced Tactical Fighter studies)中提出的理论。根据这个理论，快速、高飞行高度、足够敏捷的飞机对来自后方的攻击拥有较高的免疫力。

　　美刊称，而根据在网上流传的一篇中国论文中的内容，这样设计的主要目的是为了保证歼-20在使用中国当前拥有的，例如AL-31F和WS-10这样的引擎时，也能够获得高的速度和好的机动性；而这样的引擎在推力/重量比上还不能和西方国家现有的引擎相提并论。歼-20战机选择采用三角翼，又采用相对较长的机身来解决低超音速动力的问题；再加上既大且高的偏转鸭翼，这样的设计能让它拥有更好的敏捷性。在全动垂尾的设计上，据称歼-20比传统的垂直安定面和方向舵面积设计要小40%，而且更加轻便。尽管，采用现有的引擎让其巡航能力并不值得称道；但在气动方面的设计还是很不错的。假如中国能在动力技术方面取得新的进展，这个瑕疵就能被很好的弥补。

　　2012年，中国观察家们将会继续关注歼-20的飞行测试项目的进展；同时，还将不断寻找中国在隐形战机技术领域，针对现有技术挑战开展工作的迹象。一架隐形飞机为了探测和追踪它的目标，需要在飞机上装备多种基于多种光谱原理、主动或者被动的传感器；并且需要对从这些传感器获得的数据信息进行充分融合和管理，从而给飞行员提供最简洁直观的可靠数据。类似的，为了让隐形战机作为网络化力量中的一部分，发挥它的最大效率；隐形战机需要一个高效率，低几率被拦截的噪声和数据通讯系统。为了攻克这些问题，美国付出了25年的努力；但是到目前为止，仍然没有寻得很好的解决方案。

　　美刊称，还有另外一个更加基础的问题：歼-20的设计初衷是什么？对空中战斗来说，歼-20作用很大；但是鉴于中国的地理环境因素，他们并不需要面对像F-22被设计用来对抗的那些敌对战机力量。与此同时，歼-20的武器托架太小，不足以装下大部分当前的空对地对抗武器。关于设计初衷有一种可能，也许歼-20的目标是威慑情报、监视、侦察，通过隐形的特性和速度上的优势对护航力量进行打击。