Sunday, November 11, 2007

A tad more on 054A

Just found some interesting tidbits on PLAN CIWS while reading up on some sources. Seems as if China had evaluated Kashtan as early as 1992. Somehow, it was not overly impressed by certain part of Kashtan like its system reaction time and muzzle velocity. Despite the greater rate of fire of Kashtan, Goalkeeper and Seamos were preferred in the two area that probably improves engagements vs supersonic sea-skimmers. We've seen pictures like this indicating that China is developing a Kashtan-like system:

Clearly, they do appreciate the concept of mixing short ranged SAM with CIWS. However, the performance of both the gun and the missile must be satisfactory against fast low altitude missiles. We see a system like LD-2000 in service for the army, but no such system for the navy. Why? The army is encountering helicopters, low flying aircrafts and subsonic missiles. TY-90 can encounter those, but it can't encounter something like Brahmos.

Now, back to Type 730 CIWS. Interestingly enough, it uses different fire control system than Goalkeeper and Seamos. Goalkeeper uses one radar to search and another radar to do the engagements. Seamos uses Infrared seeker to do search and TV tracking camera to do the engagements. By comparison, I believe Kashtan uses one radar to search and engages with radar or TV tracker. Type 730 combined the strength of Goalkeeper and Seamos by using TR-47C to do searching and using the combination of TV tracking camera, infrared tracking camera and laser rangefinder to do the engagement guidance. It is certainly not cheap to add all these extra "eyes" to the system, but certainly makes the tracking/engagement of Type 730 better than the other two.

As for the reaction time, this is what is stated on the official site for Kashtan -> 6 to 8 seconds. That makes sense since the reaction of Tunguska-M is stated to be around 8 seconds. The Chinese sources were using 6.5s to 7 for the reaction time of Kashtan. Goalkeeper on the other hand, has a reaction time of 5.5s vs supersonic missiles. Type 730 should be around 5.5s too.

The other interesting question that has been asked is why 054 uses 4 AK-630M instead of 2 Type 730. From all evidences, each Type 730 should be stronger than 2 AK-630M. The reasons often stated are cost and putting familiar weapon system on a new hull. Another reason that was brought up is that 054 simply did not have the power to supply 2 Type 730.

Also, it's interesting to look at the fire control system of the guns of 054.

It is clearly a fusion of the rice lamp radar, the E/O tracker + the Type 360 search radar. As part of the combat system, FCU-17 gets data from information console + radar input from the E/O tracker and rice lamp radar. And uses that to control the AK-630Ms and 100 mm gun. I always found it interesting that someone questioned the data fusion of 054A, when clearly system such as JRNG shows data fusion even for naval guns that look like what's used on Poyma-E

They combine radar data from multiple sources, process them, display aerial/surface data on multiple consoles. And then these information can be used to do the engagements.

I would expect 054A to use a far more advanced combat system + a more advance fire control system for naval gun + a more advanced FCS for HH-16. In both cases, each of the sensors may be used as radar inputs for multiple FCS. Whether that is plot level or track level data fusion remains to be seen.

You might have noticed that I spent much of the time on the air defense of 054A. The truth is that 054A provides the counter against multiple sea-skimmers that doesn't currently exist in PLAN. 051C and 052C are probably more used against the horde of incoming naval strike planes rather than the actual missiles. 054A in that sense provides the middle level air defense coverage that is currently lacking in PLAN. We've already seen two 054As joining the South Sea Fleet (one as 570 and the other we don't know). They are clearly badly needed for the air defense. As for ASuW, it doesn't differ much from 051C. It has the same OTH radar, datalink and missiles. In terms of ASW, this is where most of the criticism for the ship has come from. In many ways, it seems like PLAN is not putting much emphasis on ASW for surface fleet. It remains to be seen whether or future 054 will be equipped with towed array sonar. Or maybe they will continue to rely on 093 for all major ASW tasks.


timurelame said...

How many 054As will be built to fulfill PLAN's needs?

Feng said...

Hard to say right now. They will definitely induct probably anything up to 20 or more frigates of 054 series. They have 2 054, 2 054A commissioned so far and another 2 close to being commissioned. The next batch may just be upgraded 054A or 054Bs, who knows.

timurelame said...

Which of the CIWS available today is the best in the world? Phalanx?
How does Phalanx compare to Kashtan or the others?

Feng said...

depending on the size, power, cost and engagment rquirements, there really isn't one CIWS that is just universally better. I would say Phalanx definitely still has numerous advantages. It's not the best in terms of shooting down multiple supersonic missiles, but it's compact, does not require deck penetration and affordable.