PLA AEW&C, SIGINT, EW and MPA thread

Discussion in 'Air Force' started by Sczepan, Nov 30, 2005.

  1. crobato
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    crobato Colonel
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    Notice that if you put the array in a balance beam you get the longest length. Length of the array is important because the more surface area an array has the longer the potential detection range. The bad part of it is that the array can be dangerous against side winds and crosswinds. I'm not really surprised that the Y-8 Balance beam plane crashed.

    On some of the US planes, you have the arrays back to back going across the length of the dish. That's two arrays, mind you, and they offer the largest reception area possible as you can see. The thing is, you need to mechanically rotate the arrays. Those movements and shifts in positions create shifts in gravity in the plane that affects the plane's stability.

    Without any movement and the advantage of using an aerodynamic dish, the triangle arranged phase arrays as you can see might offer the best compromise between array size and flight stability.
     
  2. tphuang
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    tphuang Brigadier
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    http://www.paktribune.com/news/print.php?id=150966
    lol, we saw Y-8 AEW coming out a while back and was speculating who it's offered to. Let's see how Pakistan rates this system. Personally, it is a little bit puzzling that China still thinks Pakistan would purchase its AEW after already purchased Erieye.
     
  3. Totoro
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    Totoro Captain
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    Lets talk about the future. How many awacs systems would china need? I'd think that depends on the threat and since it's always best to plan for the worst, that threat would be massive US strikes on china's soil (that's just for illustration of level of threat, lets not discuss it further)

    4 planes seem to be a number that allows to have one plane on station at any time, for as long as it takes. 3 would also do it for a week or two, but sooner or later there'd have to be some big maintenance work done.

    Knowing range needs to be at least till the horizon, some 430 km at 10 km altitude and knowing how many points around china need to have awacs coverage (near korea, near afghanistan, near india, vietnam, taiwan, across japan etc) one could calculate that for worst scenario (where threats come from all those direction at the same time - granted, unrealistic but theoretically possible) china would need 12 planes on station at any given time. Depending on effectiveness of sharing of resources between various areas, thats 36-48 awacs system in total. Possible (desirable) attrition reserve not counted.

    I hope china will, in some 10 year time period, be able to produce and field (and maintain) such a fleet. Of course, real world teaches us that budget constraints usually half any real but i guess even as few as 18 systems would not be that bad - though it might prove to be too much for a scenario where taiwan is invaded, where there's war between koreas, where US is threatening from afghanistan and from over india/vietnam while placing carriers more or less across whole coast.

    I do hope in that long term china will field a mix of airliner converted awacs for max flight endurance with transport based awacs fleet which could operate from unprepared and unpaved runways.

    If true that 4 kj2000 have entered service then there should be little to prevent from further units entering service during the coming years. Basically, anything less than another 4 (of any kind, doesnt have to be kj2000) in the next 365 days could signal total numbers meant to be fielded are gonna be closer to russia's awacs fleet than to one of US of A.
     
  4. kursed
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    kursed New Member

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    A Pakistani member on KeyPublishing is claiming that today morning at 6am PST he saw an AWACS plane with the radome painted in white on Chaklala Airbase. And I just read the whole thread and as tpuhang has already pointed it out it might be the Y-8 derivative with a KJ-2000 styled radar on top.
     
    #44 kursed, Jul 30, 2006
    Last edited: Jul 30, 2006
  5. kooe
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    kooe Banned Idiot

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    the news i heard this morning..... china is promotin AWACS to pakistan...
     
  6. maglomanic
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    maglomanic Junior Member

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    I am just not sure what is Pakistan trying to do here. Deal with Ercison is done deal. Why they are bringing in Chinese AWACS late into equation? I don't think Pakistan has that kind of money. Probably China will offer a complete Package including JF-17,J-10 and AWACS. Or maybe the radome AWACS offers something that the blanace beam Erieye lacks. Anyone??
     
  7. kursed
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    kursed New Member

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    360 degree radar coverage?
     
  8. maglomanic
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    maglomanic Junior Member

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    Erieye has 360 degree coverage. Search for Greek Erieye deal and it's details.
     
  9. duskylim
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    duskylim Junior Member
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    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.

    As the wavefronts add up they form a strong sum signal in the desired direction. Each wave emitted is slightly out of phase with the next - except in the desired direction - hence the name phased array.

    As can be seen from geometry, the width of the beam decreases the farther away from perpendicular we steer the beam. The beam width is proportional to the cosine of the steering angle. So at 45 degrees it is equal to 0.707... at 60 degrees 0.500 and at 90 degrees it is 0.

    Incidentally the best introduction I have read into this techonology is from the September 1981 issue of Scientific American - it was written by the Raytheon engineers who designed Cobra Judy and Cobra Dane.

    Best Regards,

    Dusky Lim
     
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  10. maglomanic
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    maglomanic Junior Member

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    Allegedly this is the photo of Chinese AWACS from Chaklala airbase.

    It was posted by Usman Shabir on PakDef.info.Credits to him.
     
    #50 maglomanic, Aug 1, 2006
    Last edited: Mar 20, 2007

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