This part of news is straight from Airforce-Technology.com so please if you have better source specifically mention PAF version of Saab 2000 Erieye AEW&C not having 360 deg coverage (plz no local news items and news items related to EMB-145 or Saab-200)I will like to agree with you
It matters little whether we have 360 deg coverage or not. You have to think about various things about the employment which can make 360 degree coverage redundant.
A couple of things about the Erieye that should be noted include:
i) Although the aircraft's dorsally mounted AESA radar does not provide 360 degree coverage, the aircraft makes up for the 60 degree blind spots (aft and fore - 30 degrees each) by using its ESM capabilities to defend itself and disrupt the AI radars of the adversary if the threat is emanating from either the aft or fore side.
ii) In most cases, a 360 degree coverage is a limited use luxury because usually the AEW capability is directionally focused, meaning that you are catering for a threat emerging from a certain set of vectors/direction(s). Think about 150 degree coverage being provided by the Erieye on the eastern front and think about what the 150 degree coverage translates into in terms of miles and you will come to the realization that even with a 150 degree over the horizon coverage, Erieye provides a very significant early warning to our air defences.
Where the 360 coverage is helpful is if and when the AEW capability is being used in disaster recovery work where due to the lack of ground facilities, an AEW platform is being used to control air traffic from all directions. However even in such cases, the Erieye AEW platform(s) can be deployed in patterns where providing such coverage is not a huge challenge.
iii) In combat situations, the AEW platform may be called upon to work in extremely dense, multi-vector situations where aircraft from various bases and locations are converging or are being vectored to and from multiple locations. In this case, full 360 degree coverage would be helpful. A very good example of this has been the use of AEW platforms in the two gulf wars where USAF and NATO E-3s were employed in this role extensively and had to monitor air traffic which at times had close to above a thousand nodes in the air at the same time from all around Iraq's neighbouring countries.
Fortunately for the PAF, the threat is primarily uni-directional and while the breadth of the air space to be monitored can be large, the threat pretty much arises from one direction (in this case from the East) and will not require very dense controlling and tracking as the number of aircraft in any Indo-Pak scenario would be limited (certainly less than 200-300 or less in the air at a time). As such having a full 360 degree coverage, aside from bragging rights, does not make or break the deal for the PAF. Had this been a major concern for the PAF, they would have gone for the Hawkeye 2000 on offer by the US with its full 360 degree coverage.