Pakistan AWACs/AEW&Cs Aircrafts

[p2prada]

even if the range is same it still holds edge over friend for paf

*more coverage
*less expansive
*the upgraded y8 is a better platform than saab 2000 with a much greater range
*reliable source

Range isn't everything. Resolution is.

As for expensive, that can only be said after you have used it for a decade. Erieye comes with proof that it is reliable. The Chinese AWACS comes with promises. Let's see if it really happens. Or else in 10 years PAF will be complaining about how frequently the radar generates problems after every few sorties as compared to the Erieye.

You see it is quite funny. I had repeatedly pointed out back in 2007 on PDF that PAF won't be getting 7 Erieyes much to the dismay of your mods, members and professionals. I said PAF won't be getting more than 5. Now it seems numbers stand at 4 with 1 extra aircraft for training. Woot! Got banned after a few days.

 

[farhan_9909]

Range isn't everything. Resolution is.

As for expensive, that can only be said after you have used it for a decade. Erieye comes with proof that it is reliable. The Chinese AWACS comes with promises. Let's see if it really happens. Or else in 10 years PAF will be complaining about how frequently the radar generates problems after every few sorties as compared to the Erieye.

You see it is quite funny. I had repeatedly pointed out back in 2007 on PDF that PAF won't be getting 7 Erieyes much to the dismay of your mods, members and professionals. I said PAF won't be getting more than 5. Now it seems numbers stand at 4 with 1 extra aircraft for training. Woot! Got banned after a few days.

well it is based on kj200 which is in service from a long time.
I think by 2015 or beyond paf might place order for more zdk03

well Indeed plan was for a total 7 Erieye but decreased

might be because of 2005 earth quake
or paf order of Chinese platform

though zdk03 was the best decision they made but the numbers need to be increased from 4.

 

[p2prada]

The radar still comes on a mechanical rotodome, will have an entirely different cooling system and a completely different radar configuration. It is not based on the KJ-200 at all. It is a different radar on the same platform.

That is not counting the effects of different aerodynamics on the platform or whether the Chinese used similar level of electronics as they did on the KJ-200.

It is a new aircraft my friend. KJ-200 or not, this one still needs proving to do and will take time for it to show. PAF themselves will inform you of it. Don't worry it is the same for our new AEW&C too. At least the platform and the maker is very reliable in this case.

PAF and PLAAF are lucky the aircraft still comes with P&W engines and western avionics.

 

[shiphone]

the engine on any new military version of Y8 family (ex. Y9, Y8 high tech serial) is WJ-6C(涡桨6c) , the power increased from 4000HP to 5000HP...the newest version of WJ6. some P&W engine was used on Y8F serial civilian version before. but there was few order for these planes.

the new 6 bladed composite propeller is also home developed , made in some city in HeBei province..

the following pic is about the test of this new propeller...this plane came from the Chinese Flight Test Establishment

the new avionics also came from some R&D unit in Sanxi


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I'm afraid the radar of ZDK03 is .Rectangular waveguide slot array antenna, mechanically scanned. the same as the APY-1 on E3A

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but the smaller sized AESA radar similar to that one on KJ2000 has been under test for years...

 

[p2prada]

the new 6 bladed composite propeller is also home developed , made in some city in HeBei province..

Hmm, so no American engines.

I'm afraid the radar of ZDK03 is .Rectangular waveguide slot array antenna, mechanically scanned. the same as the APY-1 on E3A

Now it is more realistic. So, not even ESA. Any idea how old the radar is?

Any idea what bands the ZDK-03 works in? UHF, L or S? Maybe the designation of the radar?

 

[shiphone]

the radar on ZDK-03 is one of china's second Gen air born surveillance radar projects, PD system. S-band(need more info), Electrically Scanned in vertical direction and obviously mechanically scanned in horizontal direction ...the other one is the AESA on KJ200....the third Gen is the one on KJ2000. the first Gen project was quite simple: put a land based surveillance radar on a Tu4 bomber.

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ZDK03 and the Erieye saab2000

1. ZDK03 's detection range is larger than Saab
2. ZDK03 has the all direction detection ability.
3. Saab system might can't give out the altitude data of the detected target.
4. Saab has a endurance of about 9 hours...ZDK03 might less. but ZDK03 has more air crews .
5. both AEWC has its role in PAF. and ZDK03 might be easier to integrated into one system with the future JF17 and J10 fleet.

my dear friend from Pakistan ...these info released by the chief designer of ZDK03's radar system in a interview should have some credit.

 

[farhan_9909]

well while i doubt this info because as per paf officials radar range is more than Erieye

beside this the mod in pdf named Oscar was some how involved in the zdk03 project as well some kind of integration

 

[farhan_9909]

the pakistani one has western engines this is confirmed
the picture by my Chinese friend are not of zdk03 pakistani one prototype
kj200 was offered to pak initially but pak wanted a even better

there are many more sources of it being aesa from China side

from the interview

/the most important extracts from the interview of ChaoChen who is the vice-chief designer of ZDK03

我国以机载预警雷达为突破口，实现了机载雷达装备从机械扫描到有源相控阵的跨越，没有搞无源相控阵，在世界上首次装备二维有源相控阵预警雷达，我国机载预警雷达的数字化水平已经居于国际领先地位。
translate;
"Using AEW&C radar as the focus of R&D, China successfully leap-frog directly from traditional mechanical scan to AESA, bypassing PESA. China is the first in the world to equip air-borne two dimensional (pitch, yaw) AESA in AEW&C planes. Digital hard and softwares in China's AEW&C planes are considered leaders of their disciplines and among the best in the world."

The Vice-designer also mentioned that ZDK-03 was developed based on knowledge and experiences from KJ-2000 and KJ-200.

So it can be confirmed that ZDK03 is AESA ...Chairman fatman17's infs proved remarkably accurate^^

THX TO macau boy/

 

[Apollyon]

the radar on ZDK-03 is one of china's second Gen air born surveillance radar projects, PD system. S-band(need more info), Electrically Scanned in vertical direction and obviously mechanically scanned in horizontal direction ...the other one is the AESA on KJ200....the third Gen is the one on KJ2000. the first Gen project was quite simple: put a land based surveillance radar on a Tu4 bomber.

So EMB-145 DRDO AEW&CS is Indian equivalent of KJ-200 and Phalcon AEW&C is Indian equivalent of KJ-2000 and Zdk-03 is cheap one for export.
How many KJ-200 are in service of PLAAF and what are the specs of AESA mounted on ?
Why KJ-2000 production stopped at 5, you could have got refurbished Il-76 from Ukraine ?

 

[farhan_9909]

the interview translated by a Chinese member

An Interview with the deputy head designer for the ZDK-03 project

记者：（以下简称记）曹总您好！最近环球网等网站上出现了中国为巴基斯坦研制的预警机的一些照片，其中一张 是预警机的模型，机身上有CETC的标志，这是中国电子科技集团公司的LOGO。作为该集团的科研人员，请 您简要介绍一下集团的情况，特别是集团与我国军工产业的关系。
曹晨：（以下简称曹）中国电科集团是我国军工电子与信息技术的国家队，是目前我国十大军工集团之一，200 2年成立，主要从事各类信息化武器装备及民用电子信息产品的研制。从电子元器件、国产计算机基础软硬件、整 机，一直到像区域综合指挥自动化系统、预警机、数据链这样的大系统，都是中国电科在军工领域的主要业务范围 。实际上，大家可以注意到这次出口巴基斯坦的预警机，名字叫ZDK03，其中"ZDK"å°±æ˜¯"中电科"çš„拼 音缩写，03则代表这是中国电科继空警2000、空警200之后担任总设计师单位研制出的第三个预警机型号 。
在除了预警机外的其它重大工程中，中国电科也都发挥了重要作用。比如在载人航天工程中作为副总指挥长单位， 负责了测控通信系统设备、雷达探测设备、太阳能电池和大量关键元器件的研制。在探月工程中，中国电科也是副 总指挥长单位，在卫星、运载火箭、发射场、测控通信和地面应用等五大系统中承担了研制任务。在国家公布的1 6个重大专项中，中国电科在多个专项中承担重要攻关任务，特别是在第一重大专项"核心器件、高端芯片和基础 软件（核高基）"ä¸­æ‹…任了主要角色，并在国家"极大规模集成电路制造装备及成套工艺"ç§‘技专项中承担了规划 和总体设计工作。
p/quote]
ZDK represents - Zhong Dian Ke (basically CETC in Chinese), 03 represents the third AEW project following KJ-2000 and KJ-200. CETC is also very important in other areas like manned space program and other programs.
记：雷达是预警机的主要传感器。世界上机载雷达的发展趋势是什么？我国的机载雷达技术在世界上属于什么水平 ？
曹：目前世界上机载雷达普遍往有源相控阵方向发展，无论是预警机上的机载预警雷达还是战斗机上的机载火控雷 达，都是这样，这两个领域是机载雷达最主要的领域。我国以机载预警雷达为突破口，实现了机载雷达装备从机械 扫描到有源相控阵的跨越，没有搞无源相控阵，在世界上首次装备二维有源相控阵预警雷达，也就是说雷达波束在 水平方向上和高度方向上都能电子扫描，由此也带动了战斗机火控雷达装备采用有源相控阵。从时间上来看，以色 列和瑞典是较早将有源相控阵预警雷达形成装备的国家，就是大家熟悉的"费尔康"å’Œ"平衡木"ï¼Œç¾Žå›½åˆ™æ˜¯æœ€æ—© 装备有源相控阵机载火控雷达的国家，装备在F-22上。欧洲在完成机载预警雷达的有源相控阵应用外，正在装备有源相控阵机载火控雷达，如英国的"狂风"ã€‚ 除了有源相控阵之外，机载雷达一个重要的发展方向是数字化。现在的有源相控阵，其收发组件中发射频率的产生 器件以及对波束的接收处理都是模拟的，这样收发组件的重量和体积还是过大，在飞机平台上的适装性不好。数字 化的收发组件，发射频率从低频到高频的合成是数字的，在接收处理时，在发射频率上直接进行模拟到数字的转换 ，不仅大幅度降低了重量和体积，而且波束处理非常灵活，可以在干扰方向上自动地形成最弱的接收，这样大大提 高了雷达的抗干扰能力和反杂波能力。我国机载预警雷达的数字化水平已经居于国际领先地位。
says aircraft radar is moving toward AESA Says China has successfully made the jump from mechanical radar to AESA and did not work on PESA (not entirely true here imo, but point is did not equip PESA). Calling it a 2D AESA radar, can scan electronically in azimuth and elevation. Says that everything is digitized in aircraft radar, which reduces the weight of radar equipment and improves ECM capability. Says Chinese AEW radar's digitization is already world class.
记：我国机载雷达在元器件上面的国产化率水平如何？例如发射机放大管，还有处理器的芯片、程序软件等是否受 制于国外？
曹：我国机载雷达包括固态收发组件及其里面的功率放大管在内的所有关键元器件，都是国产化的，雷达高速数据 处理所要求的处理器芯片也是我国自己研发的。在计算机方面，虽然采用商用现货是一个趋势，机上的数据处理、 情报分发和指挥控制都无需采用专门研制的军用计算机，直接采用在市场上就能买到的产品就可以基本满足需要， 但毫无疑问，这对于维护我国信息化武器装备的信息安全是有隐患的。所以，我们这几年坚持推进了包括服务器、 工作站、处理器芯片、操作系统和数据库等计算机基础软硬件的国产化工作。我们依靠国产载机平台又搞出了空警 200、ZDK03。可以这样说，通过平台、关键元器件以及计算机基础软硬件的国产化工作，我们已经把预警 机发展的主动权牢牢掌握在自己手里。
all the important components like solid state T/R modules and power amp are home made. Radar's high speed processing unit is home developed. In terms of computers, it's still using foreign product. All of the digitial processing, report and controlling has no need for specialized military computer and can get it COTS.
记：从照片看，中国出口巴基斯坦的预警机以运-8改进型为平台，美国的P-3就有预警型，早期也有用C-130做预警机平台的设想。螺旋桨飞机作为预警机平台与喷气机平台相比有哪些优缺点？
曹：原则上，只要飞机有足够的空间和气动潜力，能够允许加装雷达或其它电子系统后的大型天线并提供足够的电 力，使得雷达或电子系统的性能达到指标要求；只要飞机有足够的载荷能力，能够容纳所要求的设备和人员，螺旋 桨飞机和喷气机都是可以的。当然，螺旋桨飞机要更省油一些。
其实，相比发动机类型对预警机设计的影响来说，飞机机翼相对机身的位置对预警机设计的影响要更大一些。目前 预警机的主要气动构型是圆盘、平衡木和共形阵。圆盘和平衡木无论是上单翼还是下单翼都有这种布局，它们的共 同特点是把天线放在机背。但上单翼飞机的机翼相比下单翼飞机的机翼，离机背的雷达天线更近，对雷达波束的遮 挡要严重一些；为了减轻遮挡，需要把支架架得更高，这会带来较大的阻力，对支架的强度要求也会提高，对飞机 的操稳影响也更大。对于共形阵来说，由于前机身两侧最为宽敞，所以一般把雷达天线贴在前机身两侧安装。对于 上单翼的飞机，发动机一般下吊式放置，所以波束扫描到发动机位置时会被遮挡，而且由于雷达天线总会有一些凸 起，也可能影响到发动机进气。下单翼的飞机则不会有这么严重的问题，所以国外的共形阵飞机，包括波音707 "费尔康"ä»¥åŠ"湾流"550"海雕"ï¼Œéƒ½æ˜¯ä¸‹å•ç¿¼çš„。螺旋桨飞机一般来说也很难做成共形阵，主要是桨叶遮 挡的问题。
talks about AEW platforms in terms of power, space requirements and the shape of the radar.
记：预警机发现空中目标相对简单，但对地面目标或在山区等，如何精确确定目标，过滤掉杂波？
曹：预警机主要是看空中目标，特别是低空飞行的空中目标。地面上的运动或静止目标，预警机是不看的。美国人 搞的E-8"联合星"ç³»ç»Ÿï¼Œå…¶å®žä¸å«åšé¢„警机。空中目标既可能在海面上，也可能在陆地上空，来自海面或陆地的雷达回 波就是杂波。虽然海杂波比陆地杂波要弱，但它们的强度都可能比来自目标的回波强上十万倍甚至更多，如果通过 回波强度来区分，杂波就会掩盖目标。为了具备反杂波能力，现代的预警雷达都采用脉冲多普勒技术，利用目标和 杂波（地面或海面）相对于预警机的速度的不同来把目标和杂波区分开来。对于E-8这样的系统，与预警机相反，来自飞机的回波是要被过滤掉的，来自地面的回波才是需要的。它通过合成孔径体 制的雷达对地面成像，预警机上则是脉冲多普勒体制的雷达。
talks about tracking ground targets. E-8 joint stars was designed for this. Talks about the usage of SAR which is better for detection targets with sea clutter than multi-mode radar on AEW.

记：在研制预警机和其它电子设备较多的军机时，电磁兼容是一个较大的问题，怎样处理好这个问题？我国做得怎 样？
曹：谈起电磁兼容问题，人们首先想到的恐怕是EP-3电子侦察机。但实际上预警机上的电磁兼容问题更为复杂，主要是预警机上有预警雷达这样大功率、高灵敏度的 设备。另外，由于预警机比电子侦察机执行的任务更多，所以电子设备的种类也更多。应该说，以空警2000装 备部队为代表，标志着我们已经完全攻克了这个难题。后面再搞空警200和ZDK03，也就不是一个技术难题 了。从技术手段来说，大致有频率隔离、空间隔离、极化隔离和时间隔离4种主要办法。频率隔离是指让不同电子 设备尽量工作在不同的频率上。由于不同的电子设备在接收时都有频率选择性，即对不同频率的信号有不同的放大 或抑制作用，因此，有可能减弱一种电子设备的信号进入另一种电子设备从而造成的干扰。空间隔离是指让不同的 电子设备尽量在空间上相隔足够的距离。由于无线电信号的功率随距离大幅度衰减，因此，即使存在干扰，那么干 扰信号进入被干扰设备的接收机时，其强度已经非常弱了。极化隔离是指不同的天线尽量采用不同的极化参数。极 化是指电磁场传播过程中电场的变化方向。不同的接收机对不同极化的电磁辐射也会有不同的接收效果。时间隔离 ，则是让不同的设备分时工作，这是最彻底的解决电磁兼容的方法。但是，各个设备不能同时工作，必然会影响电 子系统整体作战效能的发挥。
记：这样看来，解决电磁兼容问题的办法还是很多的，那么，为什么大家却一致认为这个问题是预警机工程设计的 重大难点？
曹：最重要的原因在于，这些可能的方法在应用中常常受到多种因素的限制。比如频率隔离，预警机上很多现有的 电子设备其工作频段常常是已经设计好而不可更改的。通信电台通常是HF或V/UHF频段的，二次雷达和"塔康"å¯¼èˆªç³»ç»Ÿéƒ½æ˜¯L波段的。即使理论上频段可以选择的设备，如雷达，其工作频 段的选择常常受到其它很多条件的限制，绝不可能仅仅从电磁兼容的角度来选定。再者，预警机上的空间也是非常 有限的，很多设备并不能随意和随地布置，因此，要使各种辐射源的布局设计达到一定的空间隔离也是非常困难的 。而在极化隔离方面，一个常见的限制是，以雷达为例，它所观察的地面或海面，在某种极化下，其反射特性更弱 ，便于雷达接收到更少的杂波，但这种特性可能会同电磁兼容的需要产生矛盾。正是这样的多方面的甚至是互相矛 盾的因素的相互作用，增加了解决预警机电磁兼容问题的难度。这就需要在设计时做好计算机仿真预测与计算分析 ，对设备的很多电性能提出具体的规范要求，充分地开展各项试验，调整好系统的各项参数等等。
记：雷达和其它设备的散热是一个重要问题，特别是在巴基斯坦或中东那样炎热的环境，可能采取的改进手段有哪 些？散热设备占的空间和重量大吗？
曹：雷达是耗电大户，机载预警雷达发射机的峰值功率可达数百千瓦。对于相控阵预警雷达来说，如果是无源相控 阵的，热量散发有两部分是大头：一部分是放在预警机舱内的集中式发射机，另一部分是放在顶罩内的移相器。放 在舱内的集中式发射机由于发热量太大，像电扇吹风这样的强迫风冷是不行的，一般采用液体冷却的方法。而顶罩 内的移相器，可以采用强迫风冷，也可以采用液冷。对于有源相控阵的预警雷达，舱内基本上没有发热大户，发射 机化整为零放在成百上千个收发组件里。这些组件都在顶罩内，如果功率较大，肯定要用液冷，例如空警2000 。如果功率不大，可以用风冷，例如空警200。大家看到平衡木前端和后端都有孔，那就是用来冷却收发组件的 进风口和出风口。除了采用适当的冷却方式外，在新研或选用设备时，必须要使设备的存储温度和工作温度都要能 够适应用户当地的使用要求。在设备冷却的代价方面，以冷却系统目前的技术水平来看，散热每千瓦大概要增加1 .2~1.5千克的重量。如果需要散热200千瓦，就需要增重300千克左右。
记：您前面提到，相控阵雷达成为趋势，但相控阵雷达天线和传统的机械扫描天线比，也有一些先天的劣势。这些 劣势是什么？
曹：相控阵雷达天线与传统天线相比，其问题主要在于天线性能会随波束扫描角的增大而恶化，而传统天线不会有 这个问题。这是因为，对于相控阵天线来说，当扫描角偏离天线阵面法向时，波束与天线阵面不垂直，而对天线性 能起决定作用的就是与波束垂直的天线面积，称为有效面积。扫描角偏到阵面法线两侧60°时，有效面积只有全 面积的一半，天线性能会严重恶化到不能用的程度，这就是一块相控阵天线一般只能扫描左右各60°范围的道理 。而由于传统天线的波束始终与天线阵面垂直，因此对天线性能起决定作用的始终是全部的天线面积。天线性能的 恶化包括两个方面，一是主瓣变胖，也就是天线增益降低，因为主瓣是从天线射出的电波能量在空间最集中的区域 ，主瓣越宽，说明这个区域内能量越少，这对于把雷达电波投射到更远的地方是不利的。二是副瓣太高，这个也好 理解，因为从天线射出的总能量是一定的，蕴含在主瓣里的能量少了，自然跑到副瓣里的能量就多了 。
记：那么，相控阵天线的这两个方面的不足有办法克服吗？这样来说，传统天线还不会被全面淘汰？
曹：这两个方面的性能恶化中，主瓣变胖还可以通过多发几个雷达脉冲去弥补。因为相控阵雷达的波束扫描是可以 电子控制的，可以让波束扫得快些，也可以扫得慢些。扫得慢些的时候，波束扫掠过目标时，停留的时间就会越长 ，也就是发射出的脉冲就越多，回来的能量也就多了，这样就弥补了天线增益下降所导致的能量减少。但是，副瓣 抬高的这个问题无法解决，而且其影响会更严重，因为副瓣分布在各个方向上，都会照射到地面，所以会增加地杂 波强度，这对于反杂波不利。所以一般来说，机械扫描雷达的反杂波能力会更好。至于说传统天线会不会被淘汰， 我认为还不至于，它的出路在于两个方面：第一，雷达不是所有的任务都需要相控阵来解决，机械扫描雷达成本低 、使用简单，很多情况下已经够用；第二，可以将传统天线的优点同相控阵结合起来。
记：您刚才讲到可以将传统天线和相控阵天线相结合，欧洲C-295预警机雷达的设计理念是通过旋转天线罩与相控阵天线一体化设计，在天线罩直径一定的情况下，一副天线 可以沿着直径安装，长度可以相应增加，以安装更多的发射/接收模块，因此具有更大的功率、更加灵活的扫描，美国E-2C改进型也有这种设想。这种设想同您讲的是不是一个意思？
曹：是的。C-295å’ŒE-2C都是圆盘形式的。如果采用相控阵来实现全方位覆盖，至少需要三个阵面，可这两款预警机的载机都是小飞机 ，允许的圆盘尺寸都不会很大，C-295才6米，E-2C和其改进型E-2D才7米。同样尺寸的圆罩里布置3个天线阵面，相比只布置1个阵面，也就是旋转天线，毫无疑问3个阵面的 天线尺寸会小一些。而天线尺寸小了以后，探测距离就不够了。旋转天线的好处是天线尺寸可以更大一些，并且反 杂波性能好，可是扫描又不能像相控阵那样灵活快速。那么，能不能把二者结合呢？可以，这种结合叫做"机相扫 "ã€‚由于工作在相控阵扫描方式下，可以多发脉冲、降低扫描周期，探测距离还可以进一步增加。
记：您能否进一步介绍一下机械扫描是怎样同相控阵扫描结合工作的？
曹：以E-2D为例，雷达在旋转天线的过程中，如果发现某个方向有威胁目标，需要马上再次用波束照射目标，就可以用计 算机控制波束进行回扫，克服了单纯的机械扫描要再次观察目标只有等到转了一圈以后的弱点。当然，回扫的角度 不会超过天线法线两侧的60°范围。而如果仅需要观测120°空域而不是全空域，天线可以不旋转，仅用相控 阵方式工作。
记：听了您的介绍，我们知道了圆盘形预警机雷达主要有三种，一种是像空警2000这样只有相控阵扫描的，一 种是像美国E-3和俄罗斯A-50只有机械扫描的，还有一种是C-295和E-2D这样机相扫的。那么，为什么圆盘型雷达使用这么普遍？共形阵提出很多年了，为什么到目前为止还只是以色 列自己在研制？
曹：我想，这个问题牵涉到圆盘形、共形阵和平衡木这三种预警机主要气动构型的选择问题。我个人总的看法是， 在能够满足雷达探测距离要求的前提下，圆盘可能是最好的选择。如果为了满足距离要求，圆盘所能提供的天线尺 寸不够，那就要采取其它一些天线罩形式。例如平衡木形式，可以在像C-295这样大小的飞机上把平衡木的长度做到9米以上，采用共形阵形式，可以在"湾流"550这样大小的飞机 上把天线阵面尺寸做到10米×2米，这种尺寸都是圆盘所不能达到的。但在做到天线大尺寸的同时可能会以牺牲 全方位性能为代价。平衡木机头和机尾有盲区；共形阵机头和机尾虽然能够覆盖，但距离要近得多。而对于圆盘来 说，不管是转的，还是不转的，都能够满足全方位均匀覆盖的要求，而且圆盘的兼容性非常好，同样一个圆盘，既 能做转的，又能做不转的，两个都有优势。
记：为了弥补平衡木的方位盲区，E-737上加装了顶帽，这是否能很好地解决平衡木的问题？另外，您刚才提到，共形阵也有方位探测不均匀的问题 ，能否再解释一下？
曹：E-737平衡木上面增加的顶帽天线，它的波束射出方向是朝向机头和机尾的，而且对天线波束性能起作用的，是天 线在机头和机尾方向的尺寸，这个尺寸很大，而不是在翼展方向上的尺寸，所以能够较好地弥补盲区。这种天线的 波束射出方向与天线所在平面平行，而不是像侧射天线那样与天线所在平面垂直，称为端射天线。我们早期有线电 视还没有普及的时候采用的八木天线就是最早的端射天线。但这种天线在目前的技术水平上，增益和所能够达到的 最大扫描角都还不能同侧射天线匹配，所以机头和机尾的探测距离仍然会近一些。至于共形阵，其方位探测不均匀 主要是由于机头和机尾所能允许安装的天线尺寸要比在机身两侧小很多，以波音707"费尔康"ä¸ºä¾‹ï¼Œæœºå¤´å¤©çº¿ 面积只有3平米多，只有侧面天线面积的1/6。当然，在天线面积较小的情况下，可以让雷达工作在较短的波长上来弥补，这样也能把增益提上去。所以，后 来以色列又搞的"海雕"å…±å½¢é˜µé¢„警机在头尾部的雷达天线，其工作波长为10厘米，而机身两侧的雷达，工作波 长为25厘米。但即使这样做，由于波长的倍数差异不能全部弥补天线面积上的倍数差异，所以，全方位探测还是 不均衡的。
记：现在圆盘形预警机雷达仍然普遍应用，而且新生的圆盘形预警机都在往相控阵方向发展，那么，美俄采用机械 扫描的圆盘形预警机有没有可能通过现代技术改造弥补一些劣势？
曹：首先说说美国。美国海军的圆盘形预警机从机械扫描的E-2C改进为E-2D了，这是有源相控阵结合机械扫描的新东西，影响很大，已经不能看作E-2C的升级，而是一个新的型号。美国空军的E-3预警机，其雷达还没有看到想改成有源相控阵的报道，但它也在做一些改进，例如提高发射功率、改进波形设计 、采用新器件减少处理损耗等等措施，探测距离增加了80％以上。同时在系统方面也做了很多改进，包括采用新 型宽带数据链、加强战场多源数据融合和态势形成软件改进等等，最新的升级型号为E-3G。俄罗斯的A-50预警机则要被A-100所替代，其载机将从伊尔-76改为伊尔-476，雷达将采用有源相控阵。
记：俄罗斯A-100将采用什么样的构型呢？
曹：目前还没有看到相关的更多报道。我个人觉得，采用圆盘构型的可能性要大一些。一方面，伊尔-476与伊尔-76在基本的气动布局上相似，上单翼飞机也不太可能采用共形阵。另一方面，基于伊尔-76的圆盘形构型非常成熟，以色列出口印度的伊尔-76"费尔康"ä»¥åŠä¿„罗斯自身的A-50，都是这种构型。至于是做成三面阵的还是做成单面阵的，要看威力要求是多大。如果要满足对小型战斗机4 00千米左右的发现距离要求，即使三面阵也应该足够，而这个距离相比A-50已是提高了不少。如果要提高对隐身飞机的发现能力，则用机相扫的可能性大。当然，如果威力要再提高，就 应该采用别的构型了。
记：现在大家很关心航母舰载预警机。我国现有的固定翼飞机平台，基本没有适合滑跃起飞的，像运-12那样最大起飞重量5.3吨、最大商载1.7吨的飞机，有可能改成舰载预警机吗？运-7那种最大起飞重量21吨、载重4.7吨的飞机能作为携带弹射器的航母预警机吗？
曹：E-2最大起飞重量26吨，最早是搭载8万吨级的航母。我国现在的航母平台为6万吨级，但即使如此， 运-12仍然显得太小。国产飞机中运-7的确比较接近E-2。但要注意到，运-7的最大起飞重量是21吨，比E-2的载机C-2A要轻不少，机长和翼展却要大不少。因此，运-7与母舰的适配性在实现起来要困难一些。而且C-2是专门为预警机上舰研制的，在与母舰的适配性上做了很多特殊的设计，例如机翼可折叠、雷达罩支腿高度可升 降等等。如果运-7作为一种现成的飞机去改预警机，这些设计恐怕都得采用，再加上其它的改装措施，由此带来的设计改动工作量 可能不亚于研制一型适配航母的新飞机，其基本参数也可能发生较大变化。虽然如此，在没有更好平台的条件下， 我个人认为运-7可能还是重要的选择。
记：在因为各种原因不能装备固定翼预警机的情况下，采用预警直升机在效能上会与固定翼预警机有 多大区别？
曹：舰载预警直升机的升限相比固定翼预警机要低很多。如果固定翼预警机的升限在8 000米，对贴海面飞行的飞机，最大视线距离为370千米左右；而预警直升机升限在4 000米时，最大视线距离仅有250千米左右。并且由于它机体小，人员少，指挥控制能力也要弱很多。但是它 的基本价值就在于还是能够克服地面或舰载雷达视线距离近、对低空飞行的目标探测距离只有三四十千米的缺陷， 有效防范敌人的低空突袭，这对于舰队防空有重要意义。另外，它使用灵活，对母舰的空间要求比较低，造价也便 宜，装备数量可以比固定翼预警机多很多。还有，从海面作战的多种战术需要考虑，预警直升机的雷达功能一般都 比单纯的预警机雷达功能要多，包括对海面成像、信标、反潜和气象预警等。所以，预警直升机一方面可以与固定 翼预警机配合，完成部分区域的雷达低空警戒和少量的指挥引导任务，另一方面又能执行除雷达警戒和指挥引导以 外的其它海军所特有的作战任务。
记：预警直升机有三种雷达挂载方式，分别是英国"海王"çš„机身侧部收放筒，俄罗斯卡-31的腹部收放板，法国的"超美洲豹"åŽéƒ¨æ”¶æ”¾ç­’。这三种布局各有什么特点？
曹：这三种布局总体上来说都是收放式的，因为如果采用固定式的天线结构，可能很难具备安装条件。例如，像固 定翼预警机那样把天线固定在机身上部并且架高显然不行，因为有旋翼。在想法设法获得足够大天线面积的情况下 ，到底采用什么样的挂载方式，需要结合载机的各方面情况来定。从这三种飞机的布局来比较，卡-31的腹部收放板所获得的天线面积是最大的，达到了6米×1米。当然，天线能够做到多大，还与直升机本身的 大小有关。
记：谢谢您接受我们的采访。
Getting a lazy here, will do more translation tomorrow hopefully.

 

[farhan_9909]

the zdk03 was the most latest development

 

[p2prada]

Farhan I don't think you understood what shiphone posted.

There are two versions of the ZDK-03. One with a mech scanned array and another with AESA.

The ones delivered to PAF to date are all mech scanned. The one undergoing tests now would be the AESA. While I don't doubt PAF can buy the AESA version in the future, but it seems the radar on operational aircraft are mech scanned.

This is the mech scanned array.

ESA,

Did you notice the difference between the two? The first one has 2 MS arrays and the second has 3 ES arrays.

I don't know how good the experts on your forum are, but if they couldn't guess the aircraft has 360 degree capability then there are some holes in their ability to make correct assumptions.

 

[farhan_9909]

the above picture is not of pakistani zdk03 prototype.

The designer of zdk03 didNt said the one exported to paf is not a aesa

anyway can you tell me the major advantage of aesa over of the mech scanned array?

More coverage?that can be achieved with the Rotodome

 

[p2prada]

Coverage isn't everything, it is only one aspect. AESA has superior capability, less maintenance but high initial cost. It has no hydraulics and little or no moving parts. It takes up lesser space which means you can get a better radar for the same amount of space. It still requires a higher amount of cooling. There is no single point of failure hence far more reliable. MTBF(Mean Time Between Failure) is at least 5 to 10 times higher.

Electronic advantages allow it greater range, a massive amount of targets tracked, the scanning rate is extremely fast. If a MS takes 20 seconds the AESA will take one or two seconds for a full 360 degree sweep. This is mostly because of the multiple beams formed. On MS arrays only a single beam is formed. Resolution of the target is superior and thereby superior identification. AESA has excellent ECCM capabilities and a very Low Probability of Intercept because of it's ability to switch frequencies, phase and power quickly. It is also capable of multitasking. For eg: The MS on the ZDK-03 will not be able to do a volume scan and a sea search at once. On fighters AESA allows the pilot to engage another fighter and a ground target simultaneously. Finally, AESA can also manage jamming functions.

The designer of zdk03 didNt said the one exported to paf is not a aesa

Just look at the pictures and you will know it. If there are pictures available for all 4 aircraft with their serial numbers it will get easier for you to identify.

Well, I could find only one with the serial.

 

[farhan_9909]

well still i dont why paf chose the zdk03 when kJ200 was on offer

lets wait for paf official statements

as sapper said and also reported in air force international of it being aesa

because of limited budget paf ALWAYS choose the best

 

[p2prada]

Well, you can wait for official info, no problem. It is not really hard to imagine why it is not an AESA considering how cheap the aircraft really were at $250-300Million for 4 aircraft.

It must be enough if it is required for keeping tabs on own and enemy aircraft during war time. It is extremely cheap and easier to replace as compared to Erieye.

 

[farhan_9909]

Well, you can wait for official info, no problem. It is not really hard to imagine why it is not an AESA considering how cheap the aircraft really were at $250-300Million for 4 aircraft.

It must be enough if it is required for keeping tabs on own and enemy aircraft during war time. It is extremely cheap and easier to replace as compared to Erieye.

but this is the case with most of Chinese weapons they cost less

beside this the designer had already said that we made a jump directly to aesa ignoring pesa

translation already posted

zdk03 is simply alot better than Erieye
be it cost,range or coverage

while the Erieye is a more reliable/mature platform because of being very old

 

[farhan_9909]

Insights into Chinese AEW&C development with ZDK03 deputy chief designer

January 11th, 2012 by alert5

In an interview with the deputy chief designer of the ZDK03 airborne early warning aircraft, it was revealed that all three models designed by CETC uses AESA radars.

Cao Chen also spoke extensively on the Chinese design approach for airborne early warning including carrier-borne early warning aircraft.

Alert 5 » Insights into Chinese AEW&C development with ZDK03 deputy chief designer - Military Aviation News

 

[p2prada]

but this is the case with most of Chinese weapons they cost less

It is not as simple as costing $75Million for the entire AEW&C.

Or else the Chinese would have flooded the market with such a price for AESA by now.

beside this the designer had already said that we made a jump directly to aesa ignoring pesa

Shiphone claims the same thing. The Chief designer says it is a slotted planar array according to what he posted.

What you also say is correct. ZDK-03 used a slotted planar array and then jumped to AESA from there. That's why there are two different variants of the same aircraft. So, there is an AESA version, just that PAF does not have it.

zdk03 is simply alot better than Erieye
be it cost,range or coverage

Cost yes. Range, yes. Resolution, no. Maintenance, no. Capability, no.

while the Erieye is a more reliable/mature platform because of being very old

Not one bit true. Erieye could very well be superior to the existing KJ-200 system. Saab has been making AESAs for over 2 decades now. They have manufactured and sold more AESA based AEW&Cs than China has.

 

[farhan_9909]

It is not as simple as costing $75Million for the entire AEW&C.

Or else the Chinese would have flooded the market with such a price for AESA by now.



Shiphone claims the same thing. The Chief designer says it is a slotted planar array according to what he posted.

What you also say is correct. ZDK-03 used a slotted planar array and then jumped to AESA from there. That's why there are two different variants of the same aircraft. So, there is an AESA version, just that PAF does not have it.



Cost yes. Range, yes. Resolution, no. Maintenance, no. Capability, no.



Not one bit true. Erieye could very well be superior to the existing KJ-200 system. Saab has been making AESAs for over 2 decades now. They have manufactured and sold more AESA based AEW&Cs than China has.

slotted planar array in zdk03?
Well this is a news for me
kindly post the source

well i have posted the whole interview and translation by a Chinese member as well

and noWhere he mention that zdk radar a slotted planar array but rather he said we left the development of pesa and directly jumped into aesa

while the other sources are that zdk is more of an hybrid aesa with

It uses both mechanical scanning (for horizontal) and electronic scanning (for vertical)

the zdk simply outclass Erieye in every single aspect except the reliability