Chengdu J-20 Multirole Stealth Fighter Aircraft,China

中国成都J-20多用途隐形战斗机

Date:2016-09-03 Source:wikipedia By:Globalmil Viewed:


 
The Chengdu J-20 (simplified Chinese: 歼-20; traditional Chinese: 殲-20) is a stealth, twinjet, fifth-generation fighter aircraft developed by China's Chengdu Aerospace Corporation for the Air Force (PLAAF).[8] The J-20 made its first flight on 11 January 2011, and is expected to be operational in 2018.
成都J-20(简体中文:歼- 20;中国繁体:殲- 20)是一种隐形,双发动机,第五代战斗机,由成都飞机工业(集团)有限责任公司为中国空军(PLAAF)开发。J-20的首次飞行在2011年1月11日,预计将在2018年服役。
 
China's J-20 platform has the potential to be a capable, long-range strike system in the Asia-Pacific region, with low rate initial production appearing to have begun as of January 2016.
在亚太地区中国的J-20平台已经有潜力成为一种有能力,远程打击系统,低速初始生产已经在2016年1月开始。
 
Development
发展
 
Origins
起源
 
The J-XX program was started in the late 1990s. A proposal from Chengdu Aerospace Corporation, designated Project 718, won the PLAAF endorsement following a 2008 competition against a Shenyang proposal that was larger than the J-20.
J-XX项目是上世纪90年代中后期开始,一项成都航空航天公司的投标,命名为718计划,在2008年同沈阳飞机工业集团公司(简称:中航工业沈飞)的投标310计划,它比J-20更大,在竞争中赢得中国空军认可。
 
In 2009, a senior PLAAF official revealed that the first flight was expected in 2010–11, with an service entry date by 2019.
在2009年,高级空军官员透露,首飞预计在2010年11月,在2019年进入服役。
 
On 22 December 2010, the first J-20 prototype underwent high speed taxiing tests outside the Chengdu Aircraft Design Institute.
2010年12月22日,首架歼20原型机在成都飞机设计研究所进行高速滑行测试。
 
Flight testing
飞行测试
 
On 11 January 2011, the J-20 made its first flight, lasting about 15 minutes, with a Chengdu J-10S serving as the chase aircraft.After the successful flight, a ceremony was held, attended by the pilot, Li Gang, Chief Designer Yang Wei and General Li Andong, Deputy-Director of General Armaments.On 17 April 2011, a second test flight of an hour and 20 minutes took place.On 5 May 2011, a 55-minute test flight was held that included retraction of the landing gear.
2011年1月11日,J-20进行了首次飞行,历时约15分钟,使用一架成都J-10S担任伴飞,在飞行成功后,举行了一个仪式,参加的飞行员李刚(Li Gang),首席设计师杨伟和总装备副主任李安东上将。2011年4月17日,进行第二次一个小时和20分钟的飞行测试。2011年5月5日,一次55分钟的飞行测试,包括起落架收放。
 
On 26 February 2012, a J-20 performed various low-altitude maneuvers.On 10 May 2012, a second prototype underwent high speed taxiing tests, and flight testing that began later that month.On 20 October 2012, photographs of a new prototype emerged, featuring a different radome, which was speculated to house an AESA radar. On March 2013, images of the side weapon bays appeared, including a missile launch rail.
2012年2月26日,一架歼20进行各种低空机动。2012年5月10日,第二架原型进行高速滑行试验并在一个月后进行飞行测试。2012年10月20日,一架新原型的照片出现,具有一种不同的天线罩,这被推测容纳AESA雷达。2013年3月,出现了侧武器舱的图片,包括一个导弹发射导轨。
 
On 16 January 2014, a J-20 prototype was revealed, showing a new intake and stealth coating, as well as redesigned vertical stabilizers, and an Electro-Optical Targeting System.This particular aircraft, numbered '2011', performed its maiden flight on 1 March 2014 and is said to represent the initial pre-serial standard. By the end of 2014, three more pre-serial prototypes were flown: number '2012' on 26 July 2014, number '2013' on 29 November 2014 and finally number '2015' on 19 December 2014.
2014年1月16日,J-20原型机被曝光后,呈现出新的进气口和隐身涂料,以及重新设计的垂直尾翼和一个光电瞄准系统。特别是这架飞机,编号为“2011”,2014年3月1日进行了首次飞行,被认为代表了初始预系列标准。截至2014年底,有3架初始系列原型机飞行了:编号“2012”在2014年7月26日,编号“2013”在2014年11月29日,最后编号“2015”在2014年12月19日。
 
On 13 September 2015, a new prototype, marked '2016', begun testing. It had noticeable improvements, such as apparently changed DSI bumps on the intakes, which save weight, complexity and radar signature. The DSI changes suggested the possibility of more powerful engines being used than on its predecessors, likely to be an advanced 14-ton thrust derivative of the Russian AL-31 or Chinese Shenyang WS-10 turbofan engines, though, by 2020 the J-20 is planned to use the 18-19 ton WS-15 engine, enabling the jet to super-cruise without using afterburners. The trapezoidal flight booms around the engines were enlarged, possibly to accommodate rearwards facing radars or electronic jamming equipment. The fuselage extends almost entirely up to the engine's exhaust nozzles. Compared to its "2014" and "2015" predecessors, the J-20's fuselage contains more of engine's surface area inside the stealthy fuselage, providing greater rear-facing stealth against enemy radar.
在2015年9月18日,一架新的原型,标有“2016”,开始测试。它有明显的改善,如在进气道的DSI的鼓包,这节省重量,复杂性和雷达特征。该DSI变化显示比它的前辈采用更强大的发动机的可能性,很可能是一种先进的14吨推力俄罗斯的AL-31或中国沈阳WS-10涡扇发动机,不过,到2020年J-20计划用18-19吨的WS-15发动机,使喷嘴在超音速巡航时不使用加力燃烧室。在发动机周围的梯形飞行尾喷挡板放大,可能容纳后视雷达或电子干扰设备。机身几乎完全延伸到发动机的排气喷嘴。相比之前的“2014”和“2015”,J-20的机身包含更多的发动机表面到隐形机身内,提供更大的后方来临敌人的雷达隐身。

 
In November 2015, a new J-20 prototype, numbered '2017', took to the sky. The most significant change in the new prototype is the reshaped cockpit canopy, which provides the pilot with greater visibility. The lack of other design changes suggest that "2017" is very close to the final J-20 production configuration. Since '2017' is likely the last J-20 prototype, low rate initial production of the J-20 is likely to being in 2016.It has been reported that the design of J-20 is already mature and will not directly use the 117S engine.
在2015年11月,一架新的J-20原型机,编号为“2017”,飞上了天空。在新的原型最显著的变化是改变座舱盖形状,它可提供飞行员更大的可视性。缺乏其他设计变化表明“2017”是非常接近最终的J-20的生产构造。因为“2017”很可能是最后的J-20原型,低速率初始生产的J-20有可能在2016年。它已经被报道,J-20的设计已经成熟并不会直接使用117S发动机。
 
Production
生产
 
In late December 2015, a new J-20 numbered 2101 was spotted; it is believed to be the low rate initial production (LRIP) version of the aircraft.That aircraft performed its maiden flight on 18. January 2016.
2015年12月下旬,一架新的J-20编号2101被发现;它被认为是低速初始生产(LRIP)的飞机版本。2016年1月18日进行首次飞行。
 
Design
设计
 
Characteristics
特点
 
The J-20 has a long and wide fuselage, with the chiseled nose section and a frameless canopy resembling that of the F-22 Raptor. Immediately behind the cockpit are low observable intakes. All-moving canard surfaces with pronounced dihedral are placed behind the intakes, followed by leading edge extensions merging into delta wing with forward-swept trailing edges. The aft section features twin, outward canted all-moving fins, short but deep ventral strakes, and conventional round engine exhausts.
J-20有长和宽的机身,与轮廓分明的机鼻部分和类似F-22“猛禽”的无框舱罩。驾驶舱后面的是低可观测的进气道。装在进气道背后全动鸭翼表面有明显的两面角,其次是机翼前缘扩展融入三角翼前掠后缘。尾部特征双向外倾斜的全动翼片,短而深的腹侧边条(腹鳍),和传统圆形的发动机排气口。

 
One important design criterion for the J-20 describes high instability.This requires sustained pitch authority at a high angle-of-attack, in which a conventional tail-plane would lose effectiveness due to stalling. On the other hand, a canard can deflect opposite to the angle-of-attack, avoiding stall and thereby maintaining control.A canard design is also known to provide good supersonic performance, excellent supersonic and transonic turn performance, and improved short-field landing performance compared to the conventional delta wing design.
一个为J-20设计的重要准则描述了高不稳定性。这需要在高攻角持续的俯仰控制,其中常规尾面会造成失速效果。另一方面,鸭式布局可以偏转相反的攻角,避免失速,从而保持控制。鸭翼的设计也提供了良好的超音速性能,优良的超音速和跨音速转向性能,相比传统的三角翼设计提高短场起降性能。 
 
Leading edge extensions and body lift are incorporated to enhance performance in a canard layout. This combination is said by the designer to generate 1.2 times the lift of an ordinary canard delta, and 1.8 times more lift than an equivalent sized pure delta configuration. The designer claims such a combination allows the use of a smaller wing, reducing supersonic drag without compromising transonic lift-to-drag characteristics that are crucial to the aircraft's turn performance.
前边缘外延和机身提升相结合,提高了鸭式布局的性能。这个组合设计师称产生普通三角翼的1.2倍升力,比同等大小的纯三角翼面配置1.8倍升力。设计者声称这样的组合允许使用一个较小的机翼,减少超音速阻力,而不影响跨声速升力阻力特性,是至关重要的飞机的转弯性能。
 
According to the Jamestown Foundation, the J-20 has the potential for development into a high performance stealth aircraft comparable to the F-22 Raptor, if given appropriate engines.
按照詹姆斯敦基金会的J-20具有发展潜力成为一个高性能的隐形战机媲美F-22猛禽,如果给予适当的发动机。
 
Engines
发动机
 
The prototype is believed to be initially powered by WS-10 and / or the AL-31F engines.China is currently working on an advanced domestic turbofan engine similar in performance to the Pratt & Whitney F119 coded WS-15,but there are also speculations that Saturn AL-31#117S engine may be used for the initial batch of the J-20.At the 2012 Zhuhai Air Show, Russia approached China in an unsuccessful bid to sell the Su-35, which included the 117S engines.According to the latest news, China and Russia signed a contract for 24 Su-35 in November, 2015.However, Chinese source stated that the design of J-20 is mature and it will not directly use 117S engine.
原型被认为是最初由WS-10和/或AL-31F发动机提供动力,中国目前工作在一种国内先进的涡扇发动机上性能类似普惠F119命名涡扇-15,但也有猜测土星AL-31#117S发动机可用于该J-20初始批次。在2012年珠海航展,俄罗斯和中国洽谈出售苏-35的一次不成功的交易,其中包括117S发动机,据最新消息,在2015年11月中国和俄罗斯签署了24架苏-35的合同。但是,中国消息表示,歼-20的设计是成熟的,它不会直接使用117S发动机。 
 
The production version of the J-20 is believed to be powered by the WS-15,a turbofan engine currently under development.According to Global Security, the engine core, composed of high pressure compressors, the combustion chamber, and high pressure turbines were successfully tested in 2005.An image of the core appeared in the 2006 Zhuhai Air Show.
歼20的生产版本动力被认为采用WS-15,一种目前正在研发的涡扇发动机。根据全球安全称,发动机的核心,由高压压缩机、燃烧室、高压涡轮组成在2005年测试成功,一张核心的图片出现在2006年珠海航展上。
 
Avionics
航空电子设备
 
The aircraft features a glass cockpit, with two main large color liquid crystal displays (LCD) situated side-by-side, three smaller auxiliary displays, and a wide-angle holographic head-up display (HUD).
这架飞机的特点玻璃化座舱,两个主要的大型彩色液晶显示器(LCD)并排放置,三个较小的辅助显示器,和一个广角全息平视显示器(HUD)。
 
A PLAAF Tupolev Tu-204 testbed aircraft was seen featuring a J-20 nose cone. It is believed to house the Type 1475 (KLJ-5) active electronically scanned array (AESA) radar with 1856 transmit/receive modules.
中国空军一架图波列夫TU-204试验飞机被发现配置了J-20的鼻锥。它被认为去容纳1475型(klj-5)有源电子扫描阵列(AESA)雷达采用1856个发射/接收模块。

 
Prototype "2011" featured a revised nose section with elements resembling a IRST/EOTS system, and a metal finish that loosely resembles the radar absorbing Haze Paint first used on F-16s, and reportedly included sensor fusion technology.Chinese company A-Star Science and Technology has developed the EOTS-89 electro-optical targeting system and EORD-31 IRST for the J-20 and potentially other PLAAF fighters to detect and intercept stealth aircraft.
原型“2011”特点是修改的机鼻部分与类似于红外EOTS系统,和金属表面,大致类似于雷达吸波涂料首次用于F-16的灰色涂装,据说包括传感器融合技术。中国的中陆航星科技有限公司(A-Star Science and Technology)开发EOTS-89光电瞄准系统和EORD-31 IRST系统用于歼20和潜在的其他中国空军的战斗机去探测并拦截隐形飞机。
 
Armament
武器装备
 
The main weapon bay is capable of housing both short and long-range air-to-air missiles (AAM) (PL-9, PL-12C/D &PL15 - PL-21).
主武器舱能够容纳短程和远程空 - 空导弹(AAM)(PL-9,PL-12C/ D&PL15-  PL-21)。
 
Two smaller lateral weapon bays behind the air inlets are intended for short-range AAMs (PL-9). These bays allow closure of the bay doors prior to firing the missile, thus enhancing stealth.
进气道后面两个较小的横向武器舱用于容纳短程空空导弹(PL-9)。这些托架,以便发射导弹之前关闭舱门,从而提高了隐身。
 
Stealth
隐身
 
Analysts noted that the J-20's nose and canopy use a similar stealth shaping design as the F-22, yielding similar signature performance in a mature design at the front, while the aircraft's side and axi-symmetric engine nozzles may expose the aircraft to radar.One prototype has been powered by WS-10G engines equipped with a different jagged-edge nozzles and tiles for greater stealth.
分析人士指出,歼-20的机鼻和座舱罩使用类似F-22的隐形外形设计,在前面一个成熟的设计产生类似的信号特征性能,而飞机的侧面和轴对称发动机喷嘴可能会使飞机暴露在雷达上,一架原型采用WS-10G发动机配备不同的锯齿状边缘喷嘴和瓦板用于更高的动力隐身。
 
Others have raised doubts about the use of canards on a low-observable design, stating that canards would guarantee radar detection and a compromise of stealth.However, canards and low-observability are not mutually exclusive designs. Northrop Grumman's proposal for the U.S Navy's Advanced Tactical Fighter (ATF) incorporated canards on a stealthy airframe. Lockheed Martin employed canards on a stealth airframe for the Joint Advanced Strike Technology (JAST) program during early development before dropping them due to complications with aircraft carrier recovery.McDonnell Douglas and NASA's X-36 featured canards and was considered to be extremely stealthy.Radar cross-section can be further reduced by controlling canard deflection through flight control software, as is done on the Eurofighter.
有人提出了关于鸭翼对隐身设计使用的疑虑,说明鸭翼可以保证雷达探测隐身和妥协。但是,鸭翼和低可观测性并不是相互排斥的设计。诺斯洛普公司为美国海军的先进战术战斗机(ATF)将鸭翼包含在一架隐身飞机上。洛克希德马丁联合先进攻击技术(JAST)计划在早期发展前在隐身飞机上采用鸭翼但因航空母舰回收难题放弃。麦克唐纳·道格和NASA的X-36特色鸭翼,被认为是非常隐形的。雷达截面可以通过飞行控制软件控制舵偏转进一步减少,如在欧洲做的。
 
The diverterless supersonic inlet (DSI) enables an aircraft to reach Mach 2.0 with a simpler intake than traditionally required, and improves stealth performance by eliminating radar reflections between the diverter and the aircraft's skin. Analysts have noted that the J-20 DSI reduces the need for application of radar absorbent materials.Additionally, the "bump" surface reduces the engine's exposure to radar, significantly reducing a strong source of radar reflection.
无附面层隔板超音速进气(DSI)使飞机采用一种简单的进气达到2马赫,比传统的要求,提高了隐身性能,通过消除雷达反射之间的切换和飞机表面。分析人士指出,J-20的DSI减少使用雷达吸波材料的需要。此外,“凸点”的表面减少了雷达对发动机的照射,大大降低强雷达反射源。
 
Strategic implications
战略意义
 
Political
政治
 
The first test flight coincided with a visit by United States Secretary of Defense Robert Gates to China, and was initially interpreted by the Pentagon as a possible signal to the visiting U.S. delegation. Speaking to reporters in Beijing, secretary Gates said "I asked President Hu about it directly, and he said that the test had absolutely nothing to do with my visit and there had been a pre-planned test."President Hu seemed surprised by Gates' inquiry, prompting speculations that the test might have been a signal sent unilaterally by the Chinese military.Abraham M. Denmark of the Center for New American Security in Washington, along with Michael Swaine, an expert on the PLA and United States–China military relations, explained that senior officials are not involved in day-to-day management of aircraft development and were unaware of the test.
首次试飞恰逢美国国防部长罗伯特·盖茨到中国访问,最初是由五角大楼解释为一个可能的信号给来访的美国代表团。在北京对记者说,国防部长盖茨说,“我问了胡锦涛主席关于它的正好,他说,测试绝对与我的访问无关,并曾有过一个预先计划的测试。”胡锦涛主席似乎对盖茨询问感到吃惊,促使猜测,测试可能是一个信号,中国军方单方面的。亚伯拉罕·丹麦在位于华盛顿的新美国安全中心,与迈克尔·史文,一位中国解放军和美国-中国军事关系专家,解释说高级官员不参与飞机研制的日常管理,并不知道测试。
 
Military
军事
 
Robert Gates downplayed the significance of the aircraft by questioning how stealthy the J-20 may be, but stated the J-20 would "put some of our capabilities at risk, and we have to pay attention to them, we have to respond appropriately with our own programs."The U.S. Director of National Intelligence James R. Clapper testified that the United States knew about the program for a long time and that the test flight was not a surprise.
罗伯特·盖茨贬低飞机的意义被质疑J-20怎么可能隐身,但说J-20将“把我们的一些能力面对危险,我们必须注意他们,我们要用我们自己的项目适当回应。美国国家情报总监杰姆斯R.克拉珀作证说,美国知道一个长时间的计划和飞行测试并不是一件意想不到的事情。
 
Loren B. Thompson felt that J-20's combination of forward stealth and long range puts America's surface assets at risk, and that a long-range maritime strike capability may cause the United States more concern than a short range air-superiority fighter like the F-22.In its 2011 Annual Report to Congress, the Pentagon described the J-20 as "a platform capable of long range, penetrating strikes into complex air defense environments."A 2012 report by the U.S.‐China Economic and Security Review Commission suggests that the United States may have underestimated the speed of development of the J-20 and several other Chinese military development projects.
洛伦·B.·汤普森认为,J-20组合正向隐身和远程,使美国的水面资产面临风险,而一个远程海上打击能力可能会使美国比短程空中优势战斗机诸如F-22更值得关注。在给国会的2011年年报中,五角大楼所描述的J-20为“能够远距离的平台,渗透射到复杂的防空环境。”2012年报告由美国中国经济与安全审查委员会建议美国可能低估了J-20和其他一些中国的军事发展计划的发展速度。
 
Observers are not able to reach a consensus on J-20's primary role.Based on initial photographs with focus on the aircraft's size, early speculations referred to as the J-20 as a F-111 equivalent with little to no air-to-air ability. Others saw the J-20 as a potential air superiority fighter once appropriate engines become available.More recent speculations refer to the J-20 as an air-to-air fighter with an emphasis on forward stealth, high-speed aerodynamics, range, and adequate agility. The J-20 could threaten vulnerable tankers and ISR/C2 platforms, depriving Washington of radar coverage and strike range.
观察员并不能够达到对歼-20的主要作用的共识。基于最初的照片焦点在对飞机的尺寸上,早期的猜测被称为歼-20如同F-111相当没有空对空能力。其他人看到J-20是一种潜在的空中优势战斗机一旦合适的发动机变得可用。最近的猜测把J-20看作一种空对空战斗机连同一个重点前进隐身、高速空气动力学,航程,和足够的灵活性,剥夺华盛顿的雷达覆盖范围和打击范围。
 
Cyber security
网络安全
 
In April 2009, a Wall Street Journal report indicated that, according to the Pentagon, information from the Lockheed Martin F-35 Lightning II had been compromised by unknown attackers that appeared to originate from China. There is some speculation that the compromise of the F-35 program may have helped in the development of the J-20.
2009年4月,华尔街日报的一份报告指出,根据五角大楼,来自洛克希德·马丁公司信息表明F-35闪电II已经造成损害被不明袭击者攻击似乎是起源来自中国。有一些猜测认为F-35项目的损害可能对J-20的发展有帮助。

 
Specifications
规格
 
Data from Aviation Week & Space Technology
航空航天和航天技术的数据
 
General characteristics
一般特性
 
Crew: one (pilot)
Length: 20 m (66.8 ft)
Wingspan: 13 m (44.2 ft)
Height: 4.45 m (14 ft 7 in)
Wing area: 78 m2 (840 sq ft)
Empty weight: 19,391 kg (42,750 lb)
Gross weight: 32,092 kg (70,750 lb)
Max takeoff weight: 36,288 kg (80,001 lb) upper estimate
Fuel capacity: 11,340 kg (25,000 lb)
Powerplant: 2 × Shenyang WS-10G (prototype), AL-31F (prototype) or Xian WS-15 (production) afterburning turbofans, 76.18 kN (17,125 lbf) thrust each dry, 122.3 or 179.9 kN (27,500 or 40,450 lbf) with afterburner
Wing loading: 410 kg/m2 (84 lb/sq ft)
Thrust/weight: 1.06 (prototype with interim engines)
乘员:一名(飞行员)
机长:20米(66.8英尺)
翼展:13米(44.2英尺)
机高:4.45米(14英尺7英寸) 
机翼面积:78平方米(840平方英尺) 
空重量:19391公斤(42750磅) 
总重量:32092公斤(70750磅) 
最大起飞重量:36288公斤(80001磅)的上限估计 
燃料容量:11340公斤(25000磅) 
动力装置:2×沈阳WS-10G(原型),AL-31F(原型)或西安涡扇-15(生产型)加力涡扇发动机, 76.18 kN (17125磅)净推力,122.3或179.9千牛(27500或40450磅)加力 
机翼载荷:410公斤/平方米(84磅/平方英尺) 
推力/重量:1.06(原型与临时发动机)



 
Armament
武器装备
 
PL-10 SRAAM
PL-12 Medium Range AAM
PL-10短程空对空导弹(SRAAM)
PL-12中程空空导弹(AAM)
 
J-20
歼-20
 
Role Stealth air superiority fighter / multirole combat aircraft
National origin China
Manufacturer Chengdu Aerospace Corporation
First flight 11 January 2011
Introduction 2018 (planned)
Status Low rate initial production
Primary user People's Liberation Army Air Force
Number built 8 prototypes and
4 low rate initial production fighters
Unit cost
US$110 million as of 2011
角色  隐身空中优势战斗机/多用途作战飞机 
国籍 中国 
生产厂家 成都航空航天公司 
第一次飞行 2011年1月11日
引进 2018年(计划) 
状态 低速率初始生产 
主要用户 解放军空军 
制造数字 8架原型和4架低速率初始生产战斗机 
单位成本 1亿1000万美元的2011美元

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