Wednesday, October 24, 2007

054A Air Defense

The most important part of 054A's Air defense is probably it's HH-16 medium ranged SAM. In order to understand it, one probably should look at Shtil system. The setup of HH-16 air defense on 054A is similar in most aspects to that of SA-N-7 on Sov, so we can start by studying some of the articles on that system. Then we will look at Shtil VLU for further guidance on the performance of a VLS system over a traditional launcher. Please right click to see the article more clearly, they are written in Chinese:

Shtil (SA-N-7) was developed in the 80s with bombers, fighter-bombers, fighters, helicopters and different types of missiles to counter in mind. On each of the Soviet 956, there are launchers of 24 missiles on both front and end of the ship. It is similar to MK-13 launching SM-1. There are 6 illuminators per ship to allow for engagements against 6 targets. In early 90s, improved shtil (SA-N-12) was developed and each system costs $15 million (not including the missiles) in 1993.

Each system consists of a 3D search radar (Top Plate), Illuminators, Optronic directors (IRST?), tracking distribution machine, target display machine, firing control machine, central processing computer, missiles, launcher,

Diagram of the system, Top Plate has search and tracking mode. In search/Early warning mode, the data is collected for OK-10B and then passed to central processing machine. In tracking mode, the targets are distributed by 2 NKO machine to 12 display terminals. These tracking data goes to the central processing machine. There are 4 optronic or TV seekers, their data can be displayed on display terminal and also passed to the central processor.
The 6 illuminators operate on C band, with 4 kW average power output and 1.2 tonne in weight. They use continuous wave illumination to illuminate one target each.

NKO divides display into 8x12=96 area. It can send the target info to any of the 12 OH-4 display terminal.
There are 12 such terminals, each one can display the information of 2 targets.
4 OT-10 TV display and is used under strong ECM environment and TV seeker is doing the main tracking.

OK-10 fire control terminal. It has two display, allowing for selection of engagement against most dangerous targets.

More up close display, shows 2 UBK central processors

This system is an improvement over previous generation since it combined the searching and tracking to one radar with Top Plate. It uses parabolic pass to encounter low altitude target and shows good performance against sea clutter and other distractions. System is modular, can have anywhere from 2 to 12 fire channels.

Talks about SA-N-12's improvements including adding inertial correction (middle course update), updates to illuminator and different missile components, new target recognition technology?, increased length by 0.2m (and range to 38 km).
It fire 30 missiles in tests. 5 of which are against AShM traveling at 3 m and they all hit the target.

List some critical stats of SA-N-7 and they include:
  • max 25 km range vs planes flying at over 1000 m and 18 km vs planes under 1000 m, min is 3.5 km. Altitude is 15 m to 15 km
  • max 12 km vs missiles less than mach 2 and 8-9 km vs missiles more than mach 2, min range is 3.5 km. Altitude is 10 m to 10 km
  • system reaction is 16 to 19 s and preparation time is less than 3 minutes
  • Rate of fire is 14 s with 1 launcher and 7 s with 2 launchers
  • Kill probability using 2 missiles is 0.81 to 0.96 against planes + 0.43 to 0.86 against missiles
  • Top Plate figures include 360 degree coverage in azimuth and 45 degree in elevation, 200 km range against 2 sqm fighter targets and 0.75 x radar horizon against 0.1 sqm missile targets (It's around 0.9 x radar horizon when missile altitude <= 10 m)

This part compares SA-N-12 to Shtil VLU. As you can see, the rate of fire sped up from 12 s to 2 s. That's the main difference with using VLS instead of conventional launcher. Clearly, SA-N-12 is a significant improvement over SA-N-7 in terms of engaging sea-skimmers.

Russia moves to vertical-launch Shtil
Miroslav Gyürösi

Russia is offering a vertical-launch (VL) version of the Shtil-1 naval surface-to-air missile (SAM) system, writes Miroslav Gyürösi. The move from a system based on trainable launchers to one based on below-deck VL modules is similar to that taken by the US Navy in the mid-1980s when it switched from a Mk 26 trainable launcher to a VL system for the sixth and subsequent Ticonderoga-class Aegis cruisers.

Russian Public Joint Stock Company DNPP (Dolgoprudnenskoye naucsno - proizvodstvennoye predpriyatie), which is part of the Almaz-Antey Air Defence Concern, developed the new 9M317ME SAM as an upgrade for the Shtil-1 naval air-defence system. Developed by the Altair Naval Radio Electronics Scientific Institute Public Joint Stock Company, which is also a member of the Almaz-Antey Air Defence Concern, Shtil-1 is an improved version of the earlier Shtil system that is the export variant of the M-22 Uragan system fitted to the Project 956 (Sovremenny-class) destroyers.

The 9M38 missile was developed in the 1970s to be a common round for the land-based 9K37 Buk (SA-11 'Gadfly') and naval Uragan/Shtil (SA-N-7 'Gadfly') system. It used a configuration similar to that of the US Standard Missile, with cruciform wings of long chord and short span, plus cruciform tail surfaces. In the land-based system, the 9M38 was fired from 9A38 and 9A310 self-propelled launch vehicles, while the naval Shtil and Shtil-1 systems used a trainable launcher fed by a below-deck loading system based on 12-cell drum magazines.

In the early 1990s, development started on an improved 9M317 missile able to replace the 9M38. This armed the Buk-M1-2 (SA-17 'Grizzly') system, which entered service with the Russian Army in 1998. The 9M317 was similar in configuration to the 9M38 but the cruciform wings were of much smaller chord and span.

The new 9M317ME missile is being marketed as a further development of the older 9M38 and 9M317 but the changes are on a scale that makes the round almost a new missile. It is designed to be fired from a cylindrical container/launcher mounted in a cell within the new Shtil-1 VL system. This arrangement provides a much higher rate of fire than the original trainable launcher and magazine system used in Shtil and Shtil-1. The latter could fire a missile every six seconds, but the 9M317ME-based system being offered for Sovremenny-class destroyers can fire rounds at one-to-two-second intervals.

The new launch technique has required drastic changes to the configuration of the missile. The long-chord wings have been replaced by vestigial fixed surfaces located not on the missile centrebody but near the rear of the airframe just ahead of the cruciform tail surfaces. These fixed surfaces may be intended to control the airflow passing the tail fins. The latter move to steer the missile - the same control scheme used on the 9M38 - but are folded to allow the round to be stored in the container/launcher.

The 9M317ME is 5.18 m long and 360 mm in diameter. The tail surfaces have a span of 820 mm when deployed.

After the round leaves the VL, a spring mechanism unfolds the tail surfaces and four gas-control vanes operating in the motor efflux turn the missile towards the required direction of flight. Once this turnover manoeuvre is completed, the gas-control vanes are no longer used. Subsequent flight control is via the moving tail surfaces.

A dual-mode solid-propellant rocket motor based on a more energetic charge than that used in the 9M38 provides the missile with a maximum speed of Mach 4.5 (1,550 m/s), a significant increase over the Mach 3.0 (1,230 m/s) of the older missile.

Guidance remains a combination of inertial and semi-active radar (SAR) homing. Inertial guidance is used in the early stages of flight and then the SAR seeker is activated to complete the interception. If the missile is being fired against long-range targets, it can receive mid-course updates while flying under inertial control. Launch weight of the 9M317ME is 581 kg. It is armed with a 62 kg warhead initiated by a dual-mode (active or semi-active) radar proximity fuze, or a contact fuze.

The range of the modernised Shtil-1 system is between 3.5-32 km, while the altitude coverage is from 5 m up to 15 km. These limits are set not by the performance of the missile but by the capabilities of the existing shipboard illuminating radars. This suggests further growth potential if the system is upgraded or if new radars are added.

The VL version of Shtil-1 is being offered for surface ships with displacement of more than 1,500 tonnes, providing protection against aircraft, helicopters, fast patrol boats and anti-ship missiles. It can also control the ship's guns. Publicly, no claims are being made for an anti-ballistic missile (ABM) capability, but the land-based 3M317 missile is reported to have successfully engaged Smerch artillery rockets and a ballistic missile during tests conducted in the mid-1990s. The VL system's ability to cope with tactical ballistic-missile threats may be limited by the performance of the existing shipboard radars.

The basic VL module contains 12 9M317ME missiles but, as with the unmodified Shtil and Shtil-1 systems, the upgrade is being offered in a series of optional configurations, which add greater numbers of MR-90 Orekh ('Front Dome') target-illumination radars and additional VL modules. All variants use target information from the ship's 3D surveillance radar.

Vertical-launch Shtil-1 configurations

Technical characteristic Option number
1 2 3 4 5 6 7 8
Reaction time, [seconds] 5 - 10 5 - 10 5 - 10 5 - 10 5 - 10 5 - 10 5 - 10 5 - 10
Firing interval [seconds] 2 - 3 2 - 3 2 - 3 1 - 2 1 - 2 1 - 2 1 - 2 1 - 2
Number of target channels 2 4 4 6 8 8 10 12
Magazine capacity [rounds] 12 24 36 48 - 72 72 108 108 - 144 144
Number of VL modules 1 2 3 4 - 6 6 9 9 - 12 12

It mentions numerous things, but an interesting stats is the bottom table. This shows reaction time of 5 to 10 s + firing rate of 1-3 s. The shtil VLU is clearly a significant improvement over the original shtil.

So, what does this mean for 054A?
First, the Sea Eagle search radar is generally believed to be newer and more powerful than Top Plate radar. It is an evolution of the Sea Eagle radar on the lone 051B. An article chronically the development process of this radar said that it went through the most grueling testing process of any naval radar in Chinese history. The title of the article states that it can "see over 500 km away". That sounds even longer than S1850M, which has much larger antenna. Even so, it does seem to be upgrade vs different targets in terms of range and reliability of detection. Here is a picture of a series of Chinese radars.

Here is what the radar on 052B, 054A and test ship 891 looks like

It seems 891's search radar has more rows of antenna than 054A, which has more rows of antenna than 052B. From the previous picture, it would indicate that 052B is operating on E band (like it should, since it's Top Plate), 054A and 891's search radar look like they operating on different bands or possibly using different scanning methods. Either way, the pictures show that 054A's radar should be superior to that of 052B and the new one 891 is trying out should be even better. Another item of interest are the FCR, SA-N-12 was said to only need illumination during the terminal stage of engagement. At the same time, each FCR are improved so that they have two channels and can engage two targets that are "close by". The ones on 054A and 891 are said to also be able to engage two targets. Another big part of the sensory unit is the SR-64 radar, which I have talked about extensively in previous blogs. I think it could be the on-board tracking radar for Type 730 CIWS like the one that looks like bandstand for Kashtan CIWS, although we've also seen it on 071, which only has AK-630 and AK-176. Either way, I think it's integrated into the combat system as part of HH-16 air defense. Other sensors in the suite include the IRST that is installed on the front mast and what looks to be an E/O tracker placed closed to the bandstand radar. Although, that sensor looks different from the E/O tracker we see on 054 and 022. Either way, 054A has a whole set of sensors that are generally speaking far more advanced than what was on 956 and more advanced than what was placed on 052B.

And the final question is what level of data fusion there is. From the SA-N-7 system diagram, it's clear that it has tracking level integration between the optronic sensors and Top Plate. One question that was challenged to me a while back is whether or not it has plot level integration. We know that the system reaction time has improved from 16-19 s to 5-10 s for SA-N-12. Most of that is probably due to the much better sensors, but it could also be due to a plot level integration. Either way, we have data fusion on 052C between the 4 large AESA radar panels, so we know that such technology is possible for 054A. And we have also seen 891 testing the entire air defense suite (see previous blogs), which suggestion a high level of integration between all of the sensors involved. Therefore, we can only say at the present time that 054A has at least tracking level integration and might have plot level integration also.

Finally, if I was to go through certain performance parameter on HH-16, I would say that the system reaction time and launch rate are probably close to that of VLU shtil. A launch rate of 2s per launch is probably expected from a VLS unit. I would expect the system reaction time to be around 6 to 7 s, since that is the figure often used for the export version of HH-7. These are certainly tremendous improvements over the original shtil. As for the range of HH-16, it's often been stated as to be more than that of HQ-2. I would say that's quite likely, since HH-16's best comparison is probably ESSM with USN. Now, the range against different types of target like fighters and anti-ship missiles will probably be similar to that of Shtil. I would expect the requirements for HH-16 to be at least as good as the latest shtil or else China would've just equipped with shtil. Based on the above stats of shtil, you can get a good idea of HH-16's performance. Although it's interesting that the size of HH-16 VLS indicates that the missile itself is smaller than shtil (which is almost 600 kg).

There is also Type 730 CIWS and AK-176M left on 054A, which I will try to go through with the next article.

Thursday, October 18, 2007

Nuclear submarines

I'm sure everyone who follows PLA has seen the recent GE pictures for 094s and also clear photos of 094. I think it was a surprise for many to see 3 094 parked outside in broad daylight (about the same length and clearly larger than original 092). Personally, I'm not knowledgeable enough about submarines to provide analysis on how advanced these boats are or how quiet they are.

Therefore, I thought I'd share some comments made by certain credible poster on Chinese military bbs. Now, I'm not saying they are not necessarily true, but they have made good impressions in the past.

The points are as follows:
  • There are 3 of these 094s, but there are also another SSBN at work that does not have the humps. Apparently, that SSBN is being worked on right now at Huludao (called 094 Type 2)
  • There are at least two 092s and they will be converted to SSGNs. Each tube can hold 3 to 5 LACMs (I guess DH-10 or something like that)
  • There are 5 093s as 2005, I guess either undergoing sea tests or commissioned.
  • The first 095 or 093G is being worked on and will be launched by 2010.
  • They are expected to have 8 093/095s by 2010
  • Another 2 094s are expected by 2010
I'm not sure what we can say at the moment except that there are 094s that may or may not be commissioned. The number of 5 093s seem at least logical to give us an almost 2:1 ratio of SSNs to SSBNs (including 3 091G and 1-2 092). Huludao seems to be building nuclear subs at an extremely rapid pace. And 093 and 094 designs must be pretty formalized for them to allow so many pictures coming out.

Thursday, October 4, 2007

JF-17 and PLAAF

I've been thinking about the topic of JF-17's role in PLA for a long time and decided that this is a probably a good time to put it in words. However, before we get to this topic, a more pressing issue seems to be the semi-unveiling of Z-10 assault helicopter. At the current time, China is mainly reliant on Z-9G and modified Mi-17s as its assault helo force. There is also an assault version of Z-11, but that seems to be not in PLA's plans due to its small size. What we can clearly see with the recent photo of Z-10 is that it is a tremendous improvement over Z-9G. From the outside, it looks like it will become the stealthiest helicopter in the world once it goes into service (since Comanche is axed already). There are some speculations that its infrared signature is as small as that of Comanche, but this has yet to be verified anywhere. The radar signature definitely looks to be smaller than other stealthy helicopters out there like the Tiger. From this picture, we can't even see the intake of Z-10, but I read that it's suppose to be at the back. We know that it has all the important features of a modern attack helicopter. A MMW radar like Longbow is under development and should be fitted on top of the rotor pretty soon. From a previous picture, Z-10 has 4 pylons. Each of which can carry 4 HJ-10 ATGMs (as seen in this picture) or 4 TY-90 AAMs. The transmission of Z-10 was supposedly co-developed with Eurocopter; and might even be more advanced than that of the Tiger. The rotor system and the engine are from Agusta and P&W Canada respectively. Indigenous replacement for both are currently in development. Z-10 has even flied off with WZ-9 engine last year. However, it appears to me that WZ-9 is still far below the performance level of PT7C series. A PT7C fitted Z-10 would have the highest T/W ratio of any helicopter in the world, but the same cannot be said about WZ-9. Therefore, PLA would have to decide whether it wants to use the cheaper+indigenous engine or the foreign+vastly superior engine. My hope is that WZ-9 is only fitted on enough helicopters to ensure that it will be a viable option if the PT7C choice is ever taken away. As we go forward, it looks like Z-10/Z-9G will form a hi-lo combination like Mi-28N/Mi-24 for the Russians. Z-10 is simply too expensive in the near term to be equipped more than that. Supposedly, a first regiment of 12 Z-10 are now deployed, so I will be waiting for more pictures to come out.

When JF-17 was started, the agreement was that China will buy 250, whereas Pakistan will buy 150. It looks like Pakistan will now place an order of 250 JF-17s due to the improvements that CAC made to the plane. It is expected to be used as the work horse of PAF in mostly A2A roles. Around the world, CAC is expected to market this fighter as a replacement to the F-7 series. Depending on the choice of avionics, weapons and engine, the price tag of JF-17 could be anywhere from $10 to $20 million. In PLAAF, China already has a hi-lo combination in J-10 and J-11. Future variants of J-11 will be used for long distance strike, ground attack, anti-ship missions and long range escort missions. Its range and payload allowed it to be chosen by PLANAF over J-10 for the first generation of PLAN aircraft carrier. J-10 remains the most deadly fighter jet in PLAAF and will be work horse of PLAAF for the next 2 decades. In the past few years, it has handed lopsided defeats to su-27/J-11A/su-30mkk in PLAAF exercises. Even against J-11B (which is equipped with a newer generation of avionics), it can still achieve parity with its much smaller RCS and greater maneuverability. With the modified J-10 coming into service soon, it will be the main air superiority platform until CAC's twin-engined "J-10" and SAC's 5th generation fighter comes online. It would seem like the core of PLAAF's fighter force would not include JF-17. JH-7A will be the main strike platform in both PLAAF and PLANAF until J-11BS comes along. JF-17 is not likely to take over the role of JH-7A or J-11BS in the future. Aside from that, J-7s and J-8s currently occupy the role of cheap aircrafts in PLA. JF-17 is obviously viewed by many as the prime candidate to take over the roles of J-7 in PLAAF. I think the number of JF-17s to be deployed in this role depends on the eventual cost of JF-17 and the number of regiments PLAAF wants to keep. if PLAAF chooses to keep the current number of fighters, JF-17 will obviously get a few hundred orders. If that does not happen (as is most likely the case), JF-17 will have to fight against J-8F for orders. It may surprise many people, but a WP-14 equipped J-8F would have many advantages against JF-17 (e.g: better T/W ratio, higher payload, better supersonic performance, more space for radar+avionics). So, where does JF-17 most likely fit in? The answer seems to be in the role of Q-5 replacement. Now, it has been believed for a long time that L-15 will assume the role of replacing Q-5 as the ground attack aircraft and replacing JJ-7 as the main LIFT for PLAAF. It turns out that Hongdu has been a huge disappointment for PLAAF. L-15 is likely to not get any orders from PLAAF in the near future. A decent order is expected for JL-9, but whether it can fully achieve the requirements of PLAAF is another issue. So, what does that mean? A twin-seated JF-17 will be required by PLAAF to take over the role of L-15. Obviously, a twin-seated JF-17 can be used to train pilots. It will be a tremendous improvement over Q-5 in flight performance, range, payload and avionics. Of course, changes will need to be made by CAC to make it more suited for CAS missions. However, the relatively low cost of an attack variant of JF-17 (it will not need all the fancy avionics of an air superiority version) would make it extremely attractive to PLAAF. This seems to be the current situation for JF-17. I will follow up if I get newer information on it.