PLA AEW&C, SIGINT, EW and MPA thread

[maglomanic]

Dear Sirs:

If there are no other antennas in the Erieye system then the systems' coverage cannot be 360 degrees. This is because to electronically steer the beam we emit progressively delayed wavefronts from the small antennas along the face of the array.

Since 1981 alot of shortcomings have been over come in terms of technology generally speaking.

Please, Log in or Register to view URLs content!

"The Erieye radar provides 360° coverage with optimum performance of the radar over the 150° azimuthal sectors on each side of the aircraft. The radar can detect fighter aircraft at a range of 350km in a dense hostile electronic warfare environment, in heavy radar clutter and at low target altitudes. The radar has a sea surveillance mode.

Please kindly search for "Erieye 360 coverage" (no quotes) and you ll find enough links

"

 

[maglomanic]

Please, Log in or Register to view URLs content!

How 360 shortcoming could be over come in Erieye



"This arrangement however suffers from an obvious and significant operational limitation, as it cannot provide 360 degree coverage, using conventional active phased array technology. With each array scanning a 120 degree sector, the two sided array has a 60 degree blind sector over the nose and the tail of the aircraft, and degraded antenna performance beyond 45 degrees off the beam of the aircraft. With Sweden's compact geography this would probably not be an issue, as multiple platforms would cover a single area, and operating in pairs, the aircraft could patrol in two racetrack orbits set 90 degrees apart to provide overlapping coverage. The success of this scheme then devolves down to the capability of the computer datalink networking which links the platforms to each other or the ground air defence centre, to ensure that a comprehensive picture of the air situation exists at whatever is the central command post.

In a heavy ECM environment, where platform to platform or platform to ground datalink function is interfered with, the two sided array has thus a major limitation. Producing a three or four sided array with similar array length results in a structure with a size comparable to an E-3 AWACS radome, which in turn requires at least a 737 sized aircraft to carry it, thereby largely defeating the apparent cost advantage of the linear array concept.

A possible resolution would be the use of a supergain array, where the ultimate size of the blind sector would be determined by the array's module parameters and array length.

Another alternative which exists is the use of a rhombic four sided array geometry, with a 60-120-60-120 degree arrangement of arrays. While the rhombic arrangement will provide full 360 degree coverage, its effective antenna length is halved in the nose and tail sectors. The result is a compromise between the bulky but excellent four or three sided array, and the compact but partially blind two sided array. No publicly discussed proposals to date have involved the rhombic arrangement.

"

 

[tphuang]

Since 1981 alot of shortcomings have been over come in terms of technology generally speaking.

Please, Log in or Register to view URLs content!

"The Erieye radar provides 360° coverage with optimum performance of the radar over the 150° azimuthal sectors on each side of the aircraft. The radar can detect fighter aircraft at a range of 350km in a dense hostile electronic warfare environment, in heavy radar clutter and at low target altitudes. The radar has a sea surveillance mode.

Please kindly search for "Erieye 360 coverage" (no quotes) and you ll find enough links

"

That seems to quote 60 degrees of connected weak spot.

Anyhow, some new pictures of Chinese AWACS. I personally hate grabbing pictures off this forum, but they seem to provide some of the best pictures.

I guess they are continuing with the KJ-200 project after all.

The airframes looks like the first KJ-200 that took off

which was on a Y-8F200 airframe

 

[maglomanic]

That seems to quote 60 degrees of connected weak spot.

Not blind spot however. Just that it's optimum 150 degrees on each side.


P.S did you check the Chinese AWACS in Pakistan pic i posted?? Any comments? Is that a PAR?

 

[Totoro]

There's absolutely no reason why they shouldn't go on with kj200 project. It is silly to think that array itself was the cause of the crash. At best, a sudden gust of wind could've been the cause, like crobato once said but even that is an off chance compared with what statistics say - planes crash all the time. For various reasons. And balance beam design has been successful on various plane platform for quite some time now. Also, chances are that people that died were operators for that particular plane, not the lead engineers for the whole kj200 program. It's still a good concept and a cheaper alternative to kj2000.

 

[tphuang]

From Chinese forum, apparently, the Y-8 was 200 to 220 km from the Japanese airspace. It's still farther out than EP-3's venture near Hainan a few years back, but I'm sure the Japanese military is not so amused.

 

[Sea Dog]

There's absolutely no reason why they shouldn't go on with kj200 project. It is silly to think that array itself was the cause of the crash. At best, a sudden gust of wind could've been the cause, like crobato once said but even that is an off chance compared with what statistics say - planes crash all the time. For various reasons. And balance beam design has been successful on various plane platform for quite some time now. Also, chances are that people that died were operators for that particular plane, not the lead engineers for the whole kj200 program. It's still a good concept and a cheaper alternative to kj2000.

I totally agree. I don't think any nation including China would put their lead engineers for a project like this on one single aircraft. No doubt they lost some talented people working on the project. But the knowledge base is still likely intact and the kj2000 program won't see any long-term negative consequences as a result.

 

[maglomanic]

More Pics from Pakistan:

 

[maglomanic]

 

[tphuang]

thanks for the photos Maglomanic. btw, man, I never asked what you would like to be referred as? Mag, Maglomanic, Maggy?

btw, you can just refer to me as Feng, since that's my real name.

As for the photos, the first two seems to be taken from China, since you can still see the pla emblem (or whatever you call it). The bottom 2 should be from Pakistan, since the pla emblem are referred. I have a feeling that Pakistan will get a real big discount on this if it does decide to buy it? Why? Aside from China's usual friendship with Pakistan, PAF will almost be the first user for this product. If things go well, there will be reasons for other countries to also put in orders. I mean if China is trying to sell something that nobody is using, then it would be extremely difficult to convince other countries to put in an order.

Also, if this does go through, then I forsee a national defensive network setup by China for Pakistan. Pakistan has already bought some YLC-2 radars and YLC-6 radar. The next step could be some long and short range SAM systems networked together. And possibly set up a C4ISR system similar to the Chinese one. But that's just my opinion.