July 28, 2018: The first Chinese combat aircraft built specifically for aircraft carrier use, the J-15, has apparently been found inadequate as the main carrier warplane for the growing Chinese carrier fleet. Although the J-15 entered “mass production” in 2013 fewer than 30 have been built and the main reason for that is a growing list of reliability and capability problems the aircraft is having as those in service spend more time at sea and operating off carriers. China now has two carriers operational. The second one is still undergoing sea trials but that means the J-15s assigned to it are getting a workout as well. A third carrier, that will use a catapult instead of the current ski-jump design, will enter service in five or six years. Together these three carriers will require a total of about 200 J-15s to support operations and training (on land and at sea).

The problems with the J-15 are not surprising when you realize that the J-15 is an illegal copy of the Russian Su-33 carrier aircraft. But the Russians themselves declared the Su-33 inadequate and replaced it with a navalized version of the MiG-29, which is now in use by Russia and India.

China thought it could fix the flaws in the Su-33 where the Russians had failed but now it appears China is hustling to come up with a new aircraft design to replace the J-15 and get into production in time to equip their expanding carrier fleet with an adequate number of reliable jet warplanes. An alternative plan involves persisting in fixing the J-15 problems. China has been successful when doing that but their approach takes time, often more than a decade (as in the case of building Russian jet engines). The Chinese are now learning a lesson the Americans accepted back in the 1960s; for best results carrier warplanes should be designed and built for carrier operations. These aircraft can still be used as land-based warplanes but the carrier version begins as a carrier version. Thus the land and carrier-based American F-35s may look similar but both versions were designed and built for those two different missions.

This decision to replace the J-15 comes after four years of Chinese efforts to tinker with the J-15 to turn it into a reliable carrier aircraft. For example, by early 2014 the J-15 was equipped with an in-air refueling pod. These pods contain additional fuel and the hose and drogue refueling gear for getting the fuel to other fighters. Thus when a carrier launches four fighters, two can be equipped with the refueling pod and transfer their fuel to the other two, providing those two with more range and time in the air. This reflects the fact that carrier aircraft can carry more weight in the air than they can when taking off.

This refueling system is particularly useful for carriers (like the Chinese one) that use the STOBAR (short take-off but arrested recovery) system that substitutes a “ski jump” flight deck to replace the catapult. The CATOBAR (catapult) system is used by American carriers and allows aircraft to take off carrying more weight (of fuel or weapons) than STOBAR launched aircraft. The U.S. and Russia have such a pod system but it has never been seen on Chinese aircraft before. This is the reason why China finally decided to switch to CATOBOR starting with their third carrier. But that would mean more problems for the J-15 which was already considered a bit too heavy for a carrier-based jet fighter. Taking off heavier via CATOBAR would put more stress on the J-15 and it was becoming obvious that the J-15 would encounter more reliability problems because of that. China will have to keep using J-15s until the new aircraft appears. China could build a hundred more J-15s, while adjusting and tweaking the aircraft to fix flaws and be able to continue operations on the two STOBAR carriers while having five years to come up with a superior carrier fighter.

The J-15 officially started mass production in late 2013, a year after some J-15s were seen making touch and go landings on the new carrier Liaoning. After that several J-15s have were seen at Navy air bases painted as combat (gray), not development (yellow), aircraft. By the end of 2013, about twenty J-15s had been built for testing. The first five were exclusively for testing while those built after that were apparently intended to become service aircraft once they had all the tweaks and modifications (for problems discovered during testing) applied. This allowed China to get moving with training pilots and deck crews to handle actual carrier operations. This process could take up to a decade in order to create a core of experienced officers and NCOs (petty officers) who can safely and efficiently supervise these inherently very dangerous operations. When the number of J-15s in service expanded very slowly after 2014 it was a sign that the Chinese were not happy with the J-15 and were tinkering with the existing ones in an effort to fix the problems.

It’s long been noted that the J-15 can’t take off from the Liaoning carrying a lot of bombs or anti-ship missiles because of its STOBAR launching system. Ski jump decks are okay for fighters flying air defense missions but not anything requiring heavy loads. In contrast, the new second Chinese carrier under construction appears was designed for catapult (flat, not ski jump deck) operations. Moreover, the front wheel of the J-15 is of the type required to handle catapult launches. Meanwhile, the Liaoning J-15s can use the refueling pods if they have to carry out some long-range attack mission (with smart bombs or anti-ship missiles).

For most of the last decade, China has been developing the J-15, which is a carrier version of the Russian Su-27. There was already a Russian version of this, called the Su-33. Russia refused to sell Su-33s to China, when it was noted that China was making illegal copies of the Su-27 (as the J-11) and did not want to place a big order for Su-33s but only wanted two, for "evaluation." China eventually got a Su-33 from Ukraine in 2001, which inherited some when the Soviet Union dissolved in 1991. Ukraine never used these Su-33s but put them in storage in anticipation of eventually finding a buyer.

The first prototypes of the J-15 were under construction for two years, and the aircraft made its first flight in 2010. The Russians were not happy with this development. Russian aviation experts openly derided the J-15, casting doubt on the ability of Chinese engineers to replicate key features of the Su-33 much less improve on them. The Russian criticisms were not unwarranted, as the Chinese have screwed up copying Russian military tech in the past. But the Chinese have a lot of experience stealing foreign technology, so the J-15 was believed to have a chance of turning out to be at least as good as the Su-33. One could say the J-15 was as good as the Su-33 but then the Chinese discovered why the Russians eventually rejected the Su-33. China openly boasted of the J-15 being the equivalent of the 30 ton American F-18E. That seemed excessive the truth was that the 33 ton J-15 appeared more like the earlier 23 ton F-18A (a similar looking but quite different design from the F-18E). In the end, the J-15 failed to be as reliable or capable as the F-18A, which is why China concentrates on copying less Russian aircraft rather than American ones.

Meanwhile, Russia itself has stopped using the Su-33 in favor of the cheaper MiG-29K (which is also being used by India). The 33 ton Su-33 and the 21 ton MiG-29K were both designed to operate from the three 65,000 ton Kuznetsovs the Soviet Union was building in the 1980s. But when the Cold War ended in 1991, only the Kuznetsov was near completion. The second ship in the class, the Varyag, was sold to China and was rebuilt as the Liaoning. The smaller Gorshkov was rebuilt and sold to India (who believed the smaller MiG-29K was more suitable for this carrier). The Russians still use the Kuznetsov, which never underwent much needed refurbishment, until recently, to keep it operational.

Basic aircraft design is not the only problem he J-15, and Chinese warplanes in general have. China continues to have problems with its locally produced military jet engines. The biggest problems are with the WS-10 series, which was designed and produced in China and the government has been pressuring the aircraft manufacturers to use Chinese made engines like this instead of Russian imports. This has not been working out as the government wants. For example, the Chinese carrier fighter, the J-15, is supposed to have a more powerful Chinese made engine so that it can carry more weight using the ski jump deck on the first two new Chinese carriers. One disadvantage of the ski jump deck is that it cannot launch aircraft as heavy as a catapult can. China developed a more powerful version of their WS-10 engine (the WS-10H) for the J-15 but has only been seen in a few J-15s. Until recently J-15s were still using Russian AL-31Fs but apparently more are receiving WS-10s, but apparently not the more powerful H version. China keeps details of its WS-10 development secret, but they cannot hide which of their aircraft are using the WS-10 and which the Russian made AL-31s that the WS-10 is based on and is supposed to replace. It is obvious that WS-10s have been slow to show up and that indicates the quality control and reliability problems of the WS-10 persist despite government denials.

The Chinese went ahead and built nearly 300 WS-10s for J-11 (which the J-15 is based on) type aircraft and found the engines reliable enough to keep using. The WS-10 is still a work in progress but it is still less reliable than the Russian ones and China is willing to undergo the hassle of maintaining and replacing the WS-10s more frequently as they learn how to design and build sturdier engines of this type. The first WS-10s began showing up in J-11s back in 2004. In 2010 China revealed that it was replacing the Russian engines in its J-10 fighter, installing Chinese made WS-10A in place of the Russian made AL-31FN. Shortly after that announcement China ordered another 123 AL-31FNs, to be delivered by 2012. More AL-31s have been ordered but at the same time, more Chinese fighters were being seen with WS-10s. Despite that, the demand for AL-31s, based on the number of modern jet fighters China wants to build, is exceeding the Russian engine building capacity.

The Chinese claim the WS-10A is superior to the AL-31F, even though the WS-10A copied a lot of the Russian technology. The Chinese say they have improved on that. For example, as delivered from Russia, the original AL-31 was good for 900 hours of operation. The Chinese claim their engineers figured out how to tweak the design of the engine so that it would last for 1,500 hours. Russia has since improved their basic AL-31 lifetime to 1,500 hours, and, most recently, 2,000 hours. When pressed, the Chinese claim that they simply cannot produce enough WS-10As for all the new airframes they are building. But the reality is that the WS-10As have some serious, unpredictable and persistent reliability problems that limit the number of reliable (enough for regular use) engines available.

Back in 2011, China believed it would be free from dependence on Russia for military jet engines by 2016, which implied that Chinese engine manufacturers still had a way to go. Now the most the Chinese will admit to is that there will be no need for Russian engines by the end of the decade, maybe. Meanwhile, China continues to import AL-31s and the RD-93 (a version of the MiG-29's RD-33) for the JF-17 (an F-16 type aircraft developed in cooperation with Pakistan) from Russia. These engines are expensive, with the RD-33 going for about $3 million each and the AL-31 for about a third more.

Since the 1990s Chinese engineers have managed to master the manufacturing techniques needed to make a Chinese copy of the Russian AL-31 engine. This is part of a program that has also developed the WS-13, to replace the RD-93 as well. While the Chinese have been able to build engines that are durable, they are still having problems with reliability. Apparently, it is still worth buying more Russian engines because the Chinese models are out of action too often, which keeps the jets grounded for repairs or, worst of all, an engine change.

China has long copied foreign technology, not always successfully. But since the 1990s China has poured much money into developing a jet engine manufacturing capability. The Chinese encountered many of the same problems the Russians did in the beginning. Developing the necessary engine design and construction skills is difficult. But China has several advantages. First, they knew of the mistakes the Russians had made, and so were able to avoid many of them. Then there was the fact that China had better access to Western manufacturing technology (both legally and illegally). Finally, China was, unlike the Soviets, able to develop their engine manufacturing capabilities in a market economy. This was much more efficient than the command economy that the Soviets were saddled with for seven decades. The Chinese consider all this part of the learning process and they do learn from their mistakes. Despite all that, every year more Chinese fighters are seen with the WS-10 and there does not appear to be any sharp increase in accidents (because of engine problems). China perseveres.

Meanwhile, the Chinese can build more Su-27 clones than they can reliable engines for them, and they keep developing more Su-27 variants. The Chinese J-11 jet fighter is an illegal Chinese copy of the Russian Su-27. It all began legally in 1995 when China paid $2.5 billion for the right to build 200 Su-27s. Russia would supply engines and electronics, with China building the other components according to Russian plans and specifications. But after 95 of the Chinese built aircraft were built Russia canceled the agreement. Russia claimed that China was using the knowledge acquired with this Su-27 program to build their own copy of the Su-27, the J-11. The Chinese claimed that the J-11 was designed and built using only Chinese technology. China also has a stealthy version (J-17) of the Su-27. There is also an aircraft carrier version of the Su-30 (the Su-33, obtained from Ukraine) that became the J-15. In 2013 J-16s were spotted. This is a two-seat fighter-bomber similar to the American F-15E and nearly identical to the Russian Su-30MKK. China insists these are all Chinese designs that just happen to bear some resemblance to Russian fighters.

A replacement for the J-15 will probably an existing fighter design, especially not obviously stolen. China has several of these “designed in China” designs, mainly the 19 ton J-10 (similar to the F-16) and the more recent 36 ton J-20 stealth fighter. In an ideal world, the J-20 would be the ideal candidate but the J-20 employs more new technique and has not been in use that long. There is another Chinese stealth fighter, the 28 ton J-31 that is supposed to enter service in 2019. So China has options, but not a lot of time to create a reliable and effective carrier fighter. That might encourage them to try unmanned combat aircraft. As the old saying goes, desperation is the mother of invention.