Monday, November 26, 2007

My opinion toward Pinkov's latest article

I hope everyone had a good thanksgiving. I certainly had some good time at Las Vegas. Anyhow, there was a lot of stuff coming out this weekend regarding JH-7A. It seems like a new upgraded variant of JH-7 might be coming out. We are seeing the current JH-7A being advertised along with a EW version of JH-7. I'd like to examine it at a future blog, but Pinkov's latest article regarding flankers actually provoked more of my interest today. If you guys have read this yet, it goes something like this.

Analysis: China eyes new Russian tech

by Andrei Chang
Hong Kong (UPI) Nov 23, 2007
A Chinese military source based in Beijing has said the People's Liberation Army Air Force is negotiating with the Russian Sukhoi Aircraft Company on three new projects.
Military observers based in Moscow and Beijing say they believe the recent nadir of military cooperation between China and Russia is only temporary. China will have to rely on Russia to develop its military technologies, as Beijing has no other alternative.

The first new project involves Su-33 shipborne fighters. Experts from the Russian aviation industry are convinced that China is about to start the construction of an aircraft carrier.

"Up to the present, on the issue of the Su-33, China and Sukhoi have had three rounds of negotiations and have reached some agreement," said the source.

Nonetheless, he did not disclose what specific progress has been made in the negotiations, merely confirming that additional rounds of talks will be held. A high-level source from Sukhoi confirmed his company is most interested in discovering whether the Chinese want to purchase whole Su-33 fighters or only require Su-33 parts, and whether they will request the transfer of production technology or design blueprints.

Other sources from the Chinese military industry said that several plans were involved in the negotiations on the Su-33. One of them is that China will buy a small number of Su-33, say 10 to 24, and later request that production technologies be transferred. However, the Chinese strategy is to use some of the Su-33 technology to develop their own shipborne fighter based on the J-11B assembled domestically.

The second project under negotiation involves the newest Su-35 fighter. At the MAKS 2007 International Aviation and Space Salon held at the Zhukovsky Air Base near Moscow in August, Chinese delegates took photos and videos of the Su-35 virtually every day.

"Several Chinese delegations have visited Sukhoi and raised technical questions," the Sukhoi company representative said. He said the two sides have reached a consensus and are now working on export plans.

"At least in the foreseeable future, China's indigenous aviation technologies will not be able to produce combat aircraft similar to the Su-35," he said. "Our attitude on this issue is the same as the case of the Su-33; that is, we are only interested in exporting whole Su-35s. This is not what the Chinese delegates hoped for. They hoped to import only certain subsystems, for instance the radar systems or the engines."

The third project concerns the PLA Navy's plan to import more Su-30MK2 fighters, or upgraded variants of the aircraft. No progress has been made on this as yet, however. A plan for China to import Su-30MK3 fighters, which was negotiated earlier, has not been carried out so far.

The possibility that the navy will continue importing Su-30MK2s or Su-30MK3s appears slim, mainly because it has already started to receive China-made JH-7A fighters. Meanwhile, the upgrade of the J-11B fighter aircraft has been very comprehensive. The fighter is now capable of launching precision attacks on battleships, and can basically meet the combat requirements of the navy fleet. China may not resume the import of Su-30MK2s unless the cost of the J-11B remains too high or comes close to the cost of the Su-30MK2.

Is there any possibility that the PLA Air Force may upgrade its existing Su-30MK2s and J-11s, or the Indian Air Force's Su-30MKIs, to a combat platform close to the Su-35 standard?

Yury Bely, a general designer at Russia's NIIP Radar Design Bureau, agreed to discuss the question. "It is impossible to import the Su-35's radar system only," he said. Bely stressed that it would be more feasible to import brand new Su-35s than to try upgrading the Su-30MK2.

The Su-35 is equipped with the H035 passive phased array radar system, which has extremely powerful detection capability, Bely pointed out. The average output power of this radar is 5 kW, with peak output at 20 kW; thus the output power of the Su-30MKI and Su-30MK2 would be insufficient. When the H035 radar was tested on Su-30MK No. 503, the detection range was as far as 290 kilometers with 1 kW power output, he said.

I have to start by saying that I'm not anti-Russian or anti-Sukhoi or anything like that, but I do believe that Sukhoi's involvement with Chinese aviation is overstated.

Pinkov have wrote numerous articles regarding Sukhoi's dealing with China in Kanwa Defence Monthly (in fact like once every 2 months).

First, I think the third project should no longer be discussed at this point. China is clearly not interested in any more mkk. Simply put, PLA is more satisfied toward JH-7A than the MKKs at this point. JH-7A has better fuel efficiency, better avionics and a much better selection of weapons to choose from.

As for the second project, I can see why people would think that China want Su-35. After all, Russia is not likely to be able to offer and deliver PAK-FA to China before 2015. And most likely, it will not be available for export until 2020. Until then, su-35 is the only thing that Russia can offer to China. It seems that Russia has caught on that China is interested in 117S engine and Irbis radar. However, as in all cases, China is only interested in the technology rather than the plane itself. Of course, Russia knows that, so it's trying to package the rest of the plane and even brought up upgrading mkk with Irbis. As mentionned previously, China has tested out Irbis (even mentionned by JDW) and the result is that it is not as good as advertised. Besides, is it even believable that they can go from the 180 km detection range for Zhuk-MSE and upgraded Bars vs 5 sqm targets to 400 km vs 3 sqm targets? Not to mention that Russian radar have traditionally not being all that stealthy and makes it easier for passive radar to detect it. It is better than what China has right now, but what about in 3 to 5 years when China might get its first su-35? Will it be that advanced by then? And there is no question that China is interested in more advanced variants of AL-31, since WS-10A's maturity and production level still hasn't reached the required level. However, it seems like China is far more interested in the AL-31FM series. It has pretty much purchased this engine for J-10 + su-27 upgrades. It has signed up even contract with Salyut to do assembly of this engine series in Shenyang Liming (with ToT according to Chinese sources). Having said that, will su-35 really be better than J-11B in 3-5 years? And secondly, does China really need su-35? Will it provide any additional capability that China does not have? I would say that J-11B can be every bit as good as su-35 (especially in A2A combat) by that time. J-11B's T/W ratio can certainly be as good as su-35 with its weight reduction from su-27 and increased thrust on WS-10A. The much touted RCS reduction techniques on su-35 can and probably have already been applied on J-11B. In addition, things like modern quadriplex FBW, MAW, holographic HUD and MFDs have been incorporated on J-11B. Other than the current advantage for Irbis, does su-35 really have any avionics advantages over J-11B? And more importantly, su-35 will just be another plane that will be crushed by F-22/35 in any likely war scenario. Sure, it can match up against modern variants of the teen series, but so can J-11B. With AWACS like KJ-2000 supporting J-11B, what kind of advantages does su-35 really offer over J-11B?

Finally, China has certainly selected the flanker series for its naval fighters. Although J-10 offers a better A2A platform, it certainly doesn't have the range or payload of flankers. China has already purchased a T-10K from Ukraine for study. Chinese rumour has it that China also got 2 su-33 for testing purposes. Now, it certainly makes not a lot of sense for China to just buy su-33s, because it would not be able to use Chinese missiles and bombs. So, the only option I see in terms of export is if China is allowed to integrate its own set of avionics and missiles on this naval product.

In the end, I'm sure there are a lot of conversations between China and Sukhoi. However, China does not need Sukhoi right now. Su-35 and modern variants of su-33 have not been fully developed yet. And they are not revolutionary machinery that China cannot get in the next few years. China will continue to contact Sukhoi to try to get as much help as possible, but any big purchases are unlikely in the future. J-10 remains the front line and work horse fighter for PLA. Flankers will get plenty of orders with its greater range and potential as a multi-role aircraft, but its orders will certainly not come close to that of J-10.

Wednesday, November 21, 2007

Latest photos

It's kind of interesting that we finally got confirmation of the 2nd PLAAF regiments of JH-7A. A while back when the mysterious new JH-7A regiment came out, many of us suspected that it is the 5th division and it turned out to be true. I guess it's replacing one of the Q-5 regiments.



We also saw some new pictures of Varyag coming out. And disappointingly, it seemed to have no change from previous pictures. This is supposedly taken at the end of last month.



The other semi-exciting news that we got is the SSF exercise. As we see in this link, there are many ships involved in this exercise. The article said that

in the middle of November, SSF used more than 10 ships and planes to go through a realistic exercise using real troops, real missiles. The exercise were under extremely complex electronic environment and bad weather. This is to train new techniques, new doctrine, new cooperation. This will allow the combat capability to go up for the fleet.


To me, most of that is just propaganda, but it was definitely extremely exciting to see the AK-630s on the 022s firing off. This is not on this link, but we saw in some of the other pictures coming out of the exercise. Another interesting thing is that we saw 054 and Sov also involved in the exercise. You can see that if you click on the other pages in that link. The article doesn't change, but the pictures do. So, it seems to be a combination of both the East and South Sea Fleet. That's definitely something we don't see everyone day.

And finally, it has caught my attention that I seem to be relying too much on Chinese sources. It should be noted that I'm presenting these "rumours" not as my own belief, but rather interesting rumours that people might be interested in know. Whether one accept them or not is a different story, but that should not prevent them from having the chance to decide. While I cannot say that the sources of the rumours are perfect. From personal experiences, they are some of the more accurate ones out there. And in all honesty, far better sources than Kanwa and JDW. I read both of which (Kanwa every month) and continue to shake my head at the commentary. Those who have debated with me in the past probably knows how I feel about different sources when it comes to PLA.

Saturday, November 17, 2007

Latest from PLAN

It looks like the first Luda (105) has recently been decommissioned. It's kind of interesting that this decommissioned destroyer is actually even smaller than 054A. Quite good to see that China's classification of vessel sizes has finally begun to match the international level. Anyhow, we saw some photos of HP shipyard recently, looks like the second 054A in HP is almost ready to join a fleet somewhere. The first 054A on both HD and HP are already serving in SSF as 569 and 570. Same with 071, which is recently named as the KunLunShan class.


Also, looks like the 3rd 054A at HP might be a bit away. They are building a new dock in HP shipyard. The next 054A might not start until the dock is finished. I guess they are saving money for the carrier project.
Speaking of which, there are some rumours recently that the carrier projects will start in both Dalian and Shanghai shipyards. I'm not surprised that two will be built, but I didn't think Dalian would get any work. Also, the cost was put at 30 billion RMB each, so around 4 billion USD. I'm not sure what this includes (ie: R&D cost or not). They are supposedly looking for something that is 60k+ in standard displacement, 317 m long, 70+ m wide and can carry 55+ aircrafts (of which 30+ J-11Cs, some number of helicopters and possibly Y-7 AEWs) I know 4 billion is cheaper US carriers, but this one is smaller than CVN-77 and uses older technology. Another thing is that Chinese ships are just cheaper to build. For example, each 054A only costs 1.58 billion RMB and each 022 only costs about 100 million RMB. At this point, I'd generally take the cost rumours with a grain of salt. However, the carrier dimensions is from a much better source and seems to be comparable to Varyag dimensions (although a little larger). I do expect to see catapults on the first generation of Chinese carriers. Otherwise, beginning Y-7 AEW development at this time frame simply does not make sense. So, hopefully we will start seeing some pictures coming out for carrier construction late next year.

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.

Sunday, November 4, 2007

More on 054A

SR-64 is one of the less known, but extremely important sensors on PLAN ships. We see it on 052B/C, 051C, 054A, 071 and 054. Although no formal information is out on SR-64, it is generally believed to have the scan rate and computational power needed to track multiple low flying supersonic anti-ship missiles. A commonly flown figure is that it has a detection range of 12 KM against sea-skimmers. There is also the more improbable figure of 100 km posted by Koxinga of CDF. Either way, it's location, scan rate, radar band all point to its role as tracking sea-skimmers. Many people have suspected that it has the same role as the radar that looks like Bandstand on Kashtan equipped ships. However, we've seen SR-64 on 071 and 054, which do not have Type 730 CIWS. It's clear that track or plot data from SR-64 goes into the combat system rather than straight into Type 730 CIWS. At the moment, it's a little unclear which sensor provides the mid-course update for the missiles. It could be the light-bulb datalink, which provides mid-course update for Anti-ship missiles, but maybe also provide update for HH-16. The Sea Eagle search radar, with its 12 rpm scan rate, does not seem to have the necessary refresh rate to provide updates for HH-16. SR-64 may have the additional responsibility of mid-course update on top of tracking sea-skimmers and surface targets. Or, some other less known sensor may be providing the mid-course updates. If continuous illuminations of FCRs is required, only a maximum of 4 targets can be engaged with 8 missiles. Since only terminal illuminations is required, 054A can theoretically engage against 8 targets simultaneously (although much less in actual practice) with the number of missiles limited by the number that can be launched during that time frame and also be limited by the number that the system can provide mid-course update for. Either way, we can conclude that 054A at the current time has much better multi-target engagement capabilities than prior PLAN ships with HH-16.

The often overlooked part of 054A's air defense are Type 730 CIWS and AK-176M. I wrote several posts on SDF in the past on Type 730's capabilities. Many people believe that Type 730 is inferior to Kashtan, because it does not have the gun+missile combination of Kashtan. In reality, PLAN was never too impressed by the performance of Kashtan in test trials. In terms of sensors, it has its own FCR + E/O tracker like Goalkeeper, Palma and Kashtan. And I think we can safely assume that it is integrated into the air defense system with all the sensors. The help of SR-64 would be extremely vital for Type 730. Especially in the case of 052C, where Type 730 CIWS pretty much has to deal with all sea-skimmers below 10 m, SR-64's main data recipient will probably be Type 730 CIWS. Although, with its own high frequency FCR and E/O tracker, it can track and shoot down targets independently. At this moment, I do not have the figures on Type 730 CIWS. Although, it is believed that Type 730 CIWS can encounter multiple supersonic missiles like Goalkeeper. I've read an article that has detailed account of Goalkeeper's performance versus multiple targets, but the only place online that seems to have this is this link. A good description is as follows:
This system can track up to thirty targets, engaging the four most urgent. It will minimize the salvo length to engage as many targets as possible and is thought to be able to deal with two pairs of sea-skimming missiles as little as five seconds apart.

It is generally believed that Type 730 CIWS was required to at least match, if not exceed, the performance of Goalkeeper. Which means, with the help of on-board sensors, each Type 730 CIWS can handle 4 or 5 concurrent sea skimmers.

Finally, the most overlooked part of 054A's air defense is probably AK-176M. The one overly hyped main gun that everyone seems to know about is the Oto Melara super rapid 76 mm gun. It seems like China evaluated Oto 76 with French 100 mm pre-TianAnMen Square and decided at that time, the 100 mm was better. Later, they evaluated between AK-176 and French 100 mm and preferred AK-176. To bring out some of the reasonings used (copied off my original SDF translations):
  • they originally compared oto 76 with the 100 mm naval gun to see which one was better to import and they picked 100 mm one and AK-176 turned out to have even more advantages.
  • at that time, OTO-76 did not have the automation level of 100 mm gun. at that time, it was also easier for China to develop guided munitions for 100 mm. And 054's 100 mm was simplified by over 40% in sensors, but it's high speed shooting reliability is not good
  • Firing rate and muzzle velocity are extremely important for China due to the requirement to counter anti-ship missiles. That's where AK-176M has serious advantage.
  • China started to develop 76 mm around 92 to 94. After improving on AK-176, it did not bother to look at the super rapid OTO-76. The muzzle velocity of OTO-76 is 920 m/s, whereas AK-176 is 980 m/s. Over 5000 m, the flight time is 2.5 second shorter. Also AK-176 fires off 10 more rounds.
  • After china improved on AK-176M, it is much faster at replacing rounds than OTO-76. Auto-reload is important, the improve AK-176 can achieve reload in no time, whereas OTO-76 is behind here
  • You can always improve on sensors/automation (newer electronics) and projectile guidance (use newer rounds), but muzzle velocity, firing rate and reloading speed are extremely important too.
  • Also, the figure given for accuracy is only for single round 1000 m. When firing 60 to 90 consecutive shots, there is no difference. Also, AK-176's munition is better than OTO, as it can better defend against multiple targets in high threat environment.
I can't testify to every statement made there, but most of it did make sense to me when I first read it. Either way, China put AK-176M and a brand new FCR (different from the 100 mm's FCR) on 054A and 071, so it must be quite impressed with their performance.

Theoretically speaking, each 054A has the capability to track many targets at different flight profiles (even the fast + low ones) and also the capability to engage many of them at the same time. It's clearly quite an advanced air defense frigate (although not as sophisticated as those European "AAW frigate"). With the next set of 054 sensors currently on 891 undergoing tests, it would be interesting to see how much more capable the next batch of 054A will be. I'm looking forward to update more on Type 730 CIWS and 054A sensors + other parts like it ASuW and ASW capability in a future post. Until then, I hope this gives a good initial overview on 054A's air defense capabilities.

Saturday, November 3, 2007

Latest rumour coming out of the PLAAF land

I'd like to finish up on 054A, but there are certain air force related matters that I want to go over.

As you have all probably noticed, there was a Russian report that China will deliver 24 J-10s to Iran. Now, I have to say that the original report was full of errors just in terms of its description of J-10. It basically called J-10 a clone of Lavi (which is not close to the truth). Of course, the Israeli and American news services picked up on this and harped on China's betrayal of Israel's help. They also made sure readers noticed that American tax dollars are not only spent on J-10, but will also be forwarded to Iran, their enemy. Aside from the obvious part that the Israelis stopped helping the J-10 project in 1995 (first flight didn't come until 1998), people fail to realize that J-10 would've been completed eventually with or without the Israeli help (although there is no doubt that the Israeli assistance sped up the development process). There are several reasons why China would not sell J-10 at this point:
  1. China does not export its best technology (similar to USA and Russia). In fact, several years back, the Iranians were interested in J-8F. However, China was only willing to offer F-8IIM, so the deal fell through. Until J-11B is fully in service J-10 is by far China's most powerful aerial threat. If they would not even export J-8F to Iran, why would they export J-10?
  2. The risk of J-10 falling into American hands is too great. If J-10 is exported to Iran, then the likelihood of it falling into American hands after a confrontation against Iran is extremely high. In that case, US would be able to take it back, examine the aircraft and get all of its performance parameters. Once that happens, the effectiveness of current and future J-10 would be significantly reduced. In fact, it is actually more beneficial to US if J-10 gets exported to Iran (especially considering the likelihood of military action against it).
  3. If JF-17 is good enough for Iran, why would J-10 need to be exported. In fact, Iran was always expected to be the largest JF-17 customer outside of Pakistan. There have even been talks of an assembly line for JF-17 in Iran.
  4. China has also apparently helped Iran on Shafaq and its indigenous F-5. It can do a lot of business with Iran without having to sell its most advanced fighter, why would it do it?
  5. There is also the recent sanction by US on IRG. It's possible that any Chinese companies dealing with IRG will get sanctions. Would companies like SAC and CAC sacrifice their contracting jobs with Boeing just to make a few bucks with Iran?
In general, I think there are simply too many factors against such a move.

There have also been some rumours out regarding China's 5th generation fighter. The latest word is that SAC did not win the competition as many had suspected. Rather, it is a combined effort with CAC. In fact, it seems CAC is getting the lion share of the design work. Now, it's likely that the assembly line in Shenyang (112) will be in charge of the main final assembly rather than the one in Chengdu (132). Make a note, there is a difference between the design bureau (601 for SAC, 611 for CAC) and the actual factory producing the aircraft (112 for SAC and 132 for CAC). Due to Shenyang's experience producing heavy fighters like J-11, it might get the final assembly order, but that remains to be seen. If this is the case, then CAC might not put as much resource into the much talked about twin-engined J-10 project. Either way, there are a lot of projects for both SAC and CAC in the coming years.

Another recent rumour is the existence of JH-7B variant, but I'm still waiting for more photos to come out on that.

Finally, it seems like Russians have cut off Shenyang for the components to J-11, because they are worried that China will not make any orders for su-35, if J-11B becomes to successful (too late in my mind). But as it turns out, the domestic suppliers have stepped up and it hasn't been a problem. In fact, a recent avic1 article talked about J-11 changing engines. I'm not sure if it's talking about equipping new J-11Bs with WS-10A or just swapping older flankers with WS-10A. You can find the article here:
本报讯 近日,中国一航沈阳飞机设计研究所提前完成型号飞机换装发动机及鉴定试飞,飞机顺利转场;取得阶段性成果。一航沈阳所所长、型号总师孙聪荣获中国一航“总经理特别奖”。

型号飞机发动机换装项目是中央军委、中国一航决策的重点科研项目,从机上改装到试飞结束仅有一个月时间,周期短,任务重。

一航沈阳所充分发挥总师单位的主导作用,以高度的政治责任感和使命感,积极发扬团队合作精神,与兄弟单位通力合作,精心部署,加大管理力度,对每个工作环节制定详细的日计划,组织精兵强将专项跟踪,盯飞、盯数据、盯进度,跟产现场,服务现场,在较短时间内先后完成了方案论证、成品技术协调、改装发图与现场技术支持、地面试验、空地勤培训、试飞技术支持等各项工作。

在调板系统一项成品换装及技术鉴定试飞的关键阶段,改进的成品在试飞中出现斜板系统故障。参研人员结合飞参数据模拟飞行状态检查、分析故障机理,确定故障系控制器“收紧”与起调转换软件判故逻辑存在缺陷造成,协助承制单位制定并落实解决措施,完成试验验证,排除了故障,为提前完成阶段任务赢得了宝贵时间。

在项目实施过程中,一航沈阳所所长、型号总师孙聪精心筹划,现场指挥,对技术核心问题和影响进度的关键问题当场决策。当无损检测发现板材复合材料分层时,他立即组织专业人员集智攻关。改进方案确定后,孙聪亲自带队现场办公。由于措施得当,及时解决这一影响飞行安全的“瓶颈”问题,确保了项目阶段任务顺利完成。

一航沈阳所党委书记褚晓文多次带队深入一线,慰问指导,组织调配,鼓舞士气。各职能机关大力支持,密切配合做好后勤保障,促进问题加速解决。全所参研人员克服一个个难关,为项目顺利进行铺平了道路,创造了换装交付周期最短的奇迹。

It says that it takes one month from the start of changing engine to the end of flight test. Looks like J-11B has is finally fully indigenous.