So I sat down this afternoon and decided to wrap my head around the whole Pakistani air defense issue in light of the FC-1 purchase.
The issue as I see it is that the Pakistani Air Forces (and I am including their SAM network as part of the air forces, I don't think they all report to the PAF but it makes it simpler for the sake of talking about the overall air defense picture) currently lack a robust air defense capability.
Now, we're not talking about pilot skill, PAF vs. IAF inventories, or anything of that nature here. What I mean by that statement is that the current PAF lacks a serious long-range air defense network. Pakistan does possess a number of EW radar systems from various sources, and their EW picture is, for the most part, adequate. There is a concern that the radar picture could be muddled in some areas due to the uneven terrain found throughout the nation, but this can easily be rectified by employing an AEW&C aircraft, such as the Saab platform currently being purchased for the PAF. Personally, I would've preferred a larger platform with the ability to remain on station longer, perhaps one of the new Chinese Y-8 models, but the Saab platform is certainly not going to fall short in the radar performance category, so it should still be perfectly suitable for the needs of the PAF.
The real problem currently lies in the business end of the IADS network, the shooters. Let's examine the air picture first.
The PAF currently has to rely on relatively short-legged, older technology aircraft for the most part (the F-16A does enjoy a bit of a range benefit over the F-7s), and they lack a BVR weapon. That means that any intruder with a BVR weapon will put the PAF interceptor pilot at a disadvantage. This is currently being rectified through the purchase and co-production of the FC-1, which will employ the Chinese SD-10 BVR AAM. An upgrade for the PAF F-16 fleet is also being sought, as well as at least 18 new Block 50/52 jets, complete with AIM-120 BVR AAM capability. So, the airborne intercept portion of the equation is being addressed.
The real problem lies with the ground-based SAM network. Pakistan currently relies on the Chinese HQ-2 for strategic air defense purposes. The problem is that there only appears to be one active HQ-2 site near Islamabad, located at 33°32'40.80"N 73°16'04.44"E. There have been claims of a second HQ-2 unit near Karachi, but there is currently no evidence suggesting that this unit is still active, as the site is not visible in overhead imagery. Given the fact that Karachi is not the capital, the equipment could be being held in storage or active reserve for deployment if needed, but for the sake of argument we will proceed with the assumption that only the northern site is active, as it is the only site that can be verified at this time.
Here is an image of the active HQ-2 site near Islamabad:
The next image depicts the maximum range of the HQ-2, 35 kilometers. 35 kilometers is the range of the farthest-reaching HQ-2 variant, I am operating on the assumption that PAF missiles may have been upgraded or replaced over their service lives.
Take note that the mountanous terrain to the east and southeast will affect radar performance and the system's effectiveness will be hampered to some degree in those areas, particularly at low altitudes.
The rest of the Pakistani SAM inventory consists of short-range tactical SAM systems best suited for a point defense or ground unit support role. Clearly, the SAM side of the Pakistani IADS needs to be addressed. Pakistan has shown interest in acquiring advanced Chinese-made SAM systems, including the FT-2000, which is a rather interesting passive homing weapon. Modern Chinese SAM systems should be just as effective as some of their Russian counterparts, as China has been importing some of the best SAM systems in the world from the Russians for years now and has likely taken the opportunity, as they are so often wont to do, to check things out and figure out just what makes them tick. S-300P technology no doubt aided in the development of the very similar HQ-9 strategic SAM system.
Before one sets about redesigning the Pakistani strategic SAM network, one must first consider the goals of the IADS. The goal of the Pakistani IADS should not be to turn Pakistan into a wholly denied parcel of airspace; that would require far too many SAM systems to effectively pull off. Rather, a strategic SAM network should be positioned to protect key infrastructure elements and the government, as well as key military facilities.
In order to defend these key sites, they must be identified. For the sake of this discussion, here is a preliminary list:
-Khusab reactor complex
This list is by no means all inclusive, and is meant simply to illustrate the next point. Additionally, mobile missile facilities have been discounted as they would likely disperse in the event of a large scale conflict.
Alright, primary facilities have been identified. The next step is to identify a potential SAM system for use. The ideal choice, given the nature of their relationship at the present time, would be for Pakistan to procure the 100 kilometer range HQ-9 system from China. As can be seen by the following image, the placement of four HQ-9 units at the aforementioned locations would represent a substantial increase in the Pakistani strategic air defense capability:
Any further strategic facilities or important locations could be defended by additional HQ-9 batteries, but two batteries at each site organized into two regiments, one north and one south, could provide the basis for a robust strategic SAM network.
That leaves the matter of point defense. While Pakistan may choose to procure a European system as they already have experience operating the short-range Crotale and RBS-70 systems, there is another option I would like to present.
Surface-launched AMRAAMs are being used by a few select nations as short/intermediate-range SAM systems. Pakistan has the opportunity here to develop a similar system in cooperation with the Chinese. The SD-10 could potentially form the basis of a very effective point defense system, as well as a system that could be placed covertly along potential threat aircraft ingress routes, particularly in the mountanous regions of the nation.
The SD-10 is an active radar weapon, ostensibly needing no off-board targeting sensors provided the target can be locked on by the seeker head prior to launch. The way to get around that limitation is to provide a passive detection system based on the FT-2000's EW kit. This would allow for hostile target identification to be performed, and a few sensors positioned at the right locations could provide triangulation so as to enable the system to generate accurate target track data. Target altitudes could be generated by measuring the strength of an identified emission, or perhaps by an accurate EO or IR system. Once a track and an altitude have been identified, the parameters for a launch have been established. An SD-10 could be fired and even updated mid-course using continued examination of the track and altitude data, before going active at point-blank range to allow for the maximum amount of suprise (mid-course signals could, of course, be detected by a sensitive RWR kit, but it'd have to know what it was to classify it as hostile).
The passive/active SD-10 system would be a cheap, effective option for short-range and point defense and would also be able to serve as a gap filler in areas where terrain precludes engagement by longer-range HQ-9s positioned in the area to defend their assigned locations. All Pakistan needs to do is take the initiative and embrace this concept, and with the induction of an HQ-9 class system the overall strategic air defense network will become much more effective.
Again, a network such as this is not intended to turn the entire nation into denied airspace. That's just not possible, or even economically feasible at any rate. But with a few key adjustments and acquisitions, Pakistan could greatly increase it's defensive capabilities insofar as intruding aircraft are concerned. A more robust SAM network would also free up more aircraft from point defense or CAP duties, allowing them to be retasked for other roles.