When the People’s Liberation Army Air Force (PLAAF) acquired its first tranche of Russian-made Sukhoi Su-27SK fighters in the early 1990s, long-time observers of China’s industrial base asked two questions. The first was how long would it be before Chinese state-controlled aerospace industry was able to reverse-engineer and build unlicensed copies of the Su-27—as they had done with Russia’s Mikoyan MiG-21 decades before.

This was accomplished in slightly more than 10 years, which produced a number of “indigenous” fighter designs produced at Shenyang that are analogues of the Russian design they were copied from. The Chinese J-11B is a near copy of the Su-27, the J-15 a knockoff of the carrier-capable Su-33 and the J-16 is a duplication of the Su-30MKK models sold to the PLAAF.

The second question was how many years after that would it be before Chinese industry started to produce some next-generation, original designs by building on what they had learned from the Russians. This next phase—the emergence of “clean-sheet” fighter designs—is well underway now, and is seen in the form of the two newest Chinese fighter designs. These are the Shenyang FC/J-31 and the Chengdu J-20

The two aircraft appear externally to be stealthy designs, both are twin-engine aircraft and they are both departures from the type of developments that these two aircraft enterprises have been known for in the past.

Russian aerospace researchers and aerodynamicists have told AIN a clear “hierarchy” exists between manufacturers Shenyang and Chengdu—both subsidiaries of the CATIC group (Hall 2a Stand D252). “More recently, much of the more advanced work that has been done with fighter aircraft development has been carried out at Chengdu,” said a senior Russian aerospace scientist, speaking on condition of anonymity. “The two enterprises collaborate back and forth in different areas, but sometimes there is more of a flow of innovation in one direction than there is in the other.”

The reputation that Chengdu has for being the more innovative of the two was enhanced by the fact that its J-20 fighter emerged as a new program and made its first flight well in advance of the FC-31. Additionally, the J-20 was unofficially categorized as a program of record for the PLAAF, whereas the FC-31 was initially presented as a “for export” program in the mold of the JF-17 that was developed at Chengdu for sale and license-production in Pakistan.

Works in Progress

Despite announcements about the official status conferred on these two programs, all of the available information is that both of these new fighter concepts remain “works in progress.” This means that still only small numbers of the aircraft have been produced to date. Moreover, those aircraft have configurations different enough from each other that it makes the programs appear to be more technology demonstrators than mature, “frozen” designs.

Despite existing only as a limited number—reported to be as few as 10 units—of differently-configured aircraft, Beijing's state-controlled central television (CCTV) network announced on March 9 that the J-20 had “officially entered service” with the PLAAF. The CCTV report was accompanied by video footage of the J-20 flying in formation with the Xi’an H-6K bomber and the new Y-20 cargo lifter.

Additional J-20s are scheduled to enter service this year, according to sources that spoke to Chinese media, but no numbers were specified. At least three new variants of the aircraft have been seen on different Chinese military-themed websites.

Announcements about China’s defense sector's achievements tend to multiply in the period of March that coincides with the annual meeting of the National People’s Congress in Beijing. Most of the defense industry senior management also hold seats in this largely ceremonial parliament and/or on its communist party analogue, the NPCC.  The meeting of these two bodies is often used by industry as a platform for advertising military and technological achievements.

Analysts experienced in assessing China’s military aircraft industry have told AIN that the announcement that the J-20 has entered service is similar to what was done with the J-10 years before. The aircraft are now entered in the ledger of the PLAAF unit based at the Chengdu aerodrome, but they reportedly remain tethered to Plant No. 132 and cannot operate independently of it.

In the brief fly-by of the J-20 at the November 2016 Airshow China in Zhuhai, the two aircraft appeared to be using the same type of edge treatments and radar absorbing materials that are seen in some earlier U.S. stealth aircraft like the Lockheed Martin F-22. However, there is no visible evidence of the kind of newer-generation—and much less maintenance-intensive—stealthy materials that are part and parcel of the F-35.

On Land or On Sea?

More recently, several reports have emerged about the FC-31, the reports coming at roughly the same late-April time frame as the launching of what has been called the China’s first indigenously built aircraft carrier, CV-17. This aircraft also made its public debut at Air Show China, but two years earlier, in 2014. It is measurably smaller than the J-20 and appeared to be close to the F-35 in overall size and weight, as well as seeming to have drawn from the Lockheed Martin design in some aspects of its overall planform.

More than one authoritative source has attributed those similarities to the highly-publicized incidences of China hacking the databases of U.S. defense contractors and U.S. Air Force facilities. In the process, the Chinese industry reportedly gained access to reams of classified materials on the design of the F-35 and other U.S. weapons programs.

The FC-31’s flight demonstration at last year’s Zhuhai air show also showed that it was underpowered and was bleeding too much energy when engaged in any aerobatic maneuvering. This may be what accounts for recent statements from Chinese sources about a re-design of the FC-31 that involve changes to the outer mold lines, an overall increase in the length of the aircraft and additional structural weight. The same reports have shown photos of what is supposed to be a new prototype of the aircraft still in factory primer.

One significant change from the previous presentations of the FC-31 is that some anonymous Chinese industry sources now claim that the program is supported by either the PLAAF or the air wing of China’s navy. Some speculation centers around whether or not the FC-31 could become the aircraft of choice for the fleet of aircraft carriers that Beijing is planning to build, given the Shenyang plant’s experience with the J-15 program.

The problem that still has not been resolved with either program, say aerospace specialists in Moscow who spoke to AIN, is that both aircraft are still powered by Russian-made engines. Regular reports from China talk about new, Chinese-designed engines being available soon, but without any commitments to a precise target date.

Chen Xiangbao, vice-president of the Beijing Institute of Aeronautical Materials within the recently-formed Aero-engine Corporation of China (AECC), told Chinese news outlets in March that it “will not take a long time for our fifth-generation combat plane to have China-made engines. We also have begun to design a next-generation aviation engine with a thrust-to-weight ratio that is much higher than that of current types.”

“We are able to develop the two most important components in an advanced engine—the single crystal superalloy turbine blades and powder metallurgy superalloy turbine disks—but in mass production, the products' quality is [still] not very satisfactory,” added Chen. “The road to success is filled with setbacks and failures. [All] of the world’s engine powers have walked this road.”