By Peter Knott
This article appeared in the Jan-Feb 2020 issue of ADBR
In this second in a series of studying the orders of battle of nations in the Indo-Pacific region, we take an in-depth look at the Chinese People’s Liberation Army Air Force
The People’s Liberation Army Air Force (PLAAF) has transformed itself over the past couple of decades in step with the China’s development into a global economic powerhouse.
Gone are the copies of obsolete Soviet-era MiGs that equipped China’s PLAAF in the 1990s, replaced by the products of an increasingly sophisticated domestic aerospace industry.
However, the links with Russian technology remain strong, from the legitimate use of base aircraft designs and engines, to the more underhand methods of acquisition represented in accusations of widespread theft and espionage.
Aerospace industry products include China’s first stealth fighter, the Chengdu J-20 Mighty Dragon which is already entering service with the PLAAF’s active fighter brigades, the Shenyang J-16 – a domestic version of the Russian Sukhoi Su-30 multirole fighter equipped with indigenous avionics, weapons and engines, and the Xi’an Y-20, a large airlifter that comes close to rivalling the Boeing C-17 Globemaster III in terms of payload.
In addition, China is also fielding a host of indigenous military-grade unmanned aircraft systems (UAS) and is exporting them in rapidly increasing numbers. Further development includes advances in stealthy UAS designs which are reportedly on the verge of entering service.
With these new types, the PLAAF is becoming an all-round modern air force with the capability for a wide variety of missions – from humanitarian assistance to long-range strike.
The PLAAF’s air combat arm is nothing like that of the turn of the century. Gone is the ‘old six’, a term of endearment for the Shenyang F-6 which was a locally built MiG-19 interceptor, and which had been in service in various guises since the 1960s. Similarly, the Chengdu J-7s – a MiG-21 clone the Chinese has steadily improved over the years – are also being drawn down.
In their place are increasing numbers of modern fighters generally regarded as at least equivalent to Western 4th generation types. The tip of the PLAAF spear is without doubt the Chengdu J-20 Mighty Dragon, a large, low-observable fighter that first flew – with no small amount of fanfare – in January 2011.
At approximately 66 feet in length, the J-20 is a relatively large aircraft. Delta wings combine with all-moving twin tails and forward canards to provide agility, while in stealth mode its weapons are carried internally in a large ventral weapons bay and two secondary bays at the sides of the long fuselage.
The main bay can carry four beyond-visual-range air-to-air missiles, while two short-range missiles can be accommodated in the smaller side bays. The size of the bays suggests a focus on the air-to-air mission and that the J-20 is designed as a long-range stand-off interceptor. Avionics are said to be indigenous, although the prototypes and early production aircraft continued to be powered by the Russian Saturn AL-31 turbofan engine.
Stealth shaping is present on the J-20, with close-up photos indicating China has paid attention to refining manufacturing techniques to ensure production flaws do not compromise low-observability. However, these early prototypes and production aircraft are designed with frontal aspect stealth, with less effort made to reduce the rear-aspect radar cross-section.
The first flight was followed by a rather lengthy program of flight testing with several prototypes to refine design before the start of low rate production. The first aircraft were assigned to PLAAF operational testing units beginning in 2017. By late 2018 or early 2019 the first unit, the 9th Air Brigade at Wuhu in Anhui province, became the first active PLAAF unit to operate the new fighter. Currently, Chengdu is flight testing J-20s powered by the indigenous WS-10 engine fitted with stealthy serrated nozzles to improve rear-aspect stealth.
If the J-20 is the tip of the spear, then half of the shaft would be a variety of derivatives of the Russian Sukhoi Flanker family. China has bought a number of Russian Flanker variants, starting with the Su-27SK interceptor in the 1990s followed by the twin-seat Su-30MKK and then Su-30MK2 in the 2000s. The latter two types are multi-role fighters, with the Su-30MK2 allocated to People’s Liberation Army Naval Air Force (PLANAF) units.
In the meantime, China started producing its own Su-27s under licence, calling them the J-11As. They soon moved on to modifying these with indigenous avionics and weapons, and these are designated J-11B. By 2011, China started powering them with locally developed WS-10 turbofans. Subsequent development has resulted in the J-16, a twin-seat indigenous Su-30 again fitted with local avionics, engines and weapons, now entering service in increasing numbers.
It is unclear how many J-11/J-16s China has produced, but it is believed to be several hundred. Add to that another 400-odd Chengdu J-10s. The other half of China’s duo of mass-produced fighters, the J-10 looks like and is reputed to be closely based on the cancelled IAI Lavi, an attempt by Israel in the 1980s to produce an indigenous fighter that was eventually killed off by pressure from the US which wanted Israel to buy F-15s and F-16s.
In some respects, the J-10 does indeed look like the Lavi, and Russian sources have stated that the Israeli design served as an inspiration, at the very least for the Chinese jet. The J-10 is a single engine, delta wing that utilises forward canards for control.
Powered by the ageing AL-31 engine, the J-10 can carry an array of air-to-air and air-to-ground ordnance on 11 hardpoints (six underwing, two under the forward intake and three in the rear fuselage). China has switched production to the J-10B and J-10C, which featured progressively improved avionics as well as a redesigned, diverterless supersonic intake for improved aerodynamics and reduced radar cross-section.
The Chengdu Aircraft Corporation is continuing to flight test the marriage of the indigenous WS-10 engine with the J-10, and flying testbeds fitted with the WS-10 recently gained a serrated, low-observable engine nozzle. However, the fact the fighter is still rolling off the production line with the AL-31 suggests testing has some way to go.
The primary bomber of the PLAAF is the Xi’an H-6 which started life as a licence-built version of the 1950s-era Soviet Tupolev Tu-16 Badger.
China received its first Tu-16s in 1958, and the Xi’an Aircraft Industrial Corporation (XAC) signed a licence production agreement with the USSR to build the type in the late 1950s. The first Chinese Tu-16 flew in 1959 and was deployed in a nuclear strike role until China’s ballistic missile force took on this role in the 1970s, leaving the H-6 as a conventional strike aircraft.
Its capability expanded from free-fall bombing to the anti-ship mission and, eventually, to land-attack cruise missile missions, with the basic H-6 evolving through other sub-variants with a series of incremental upgrades to its sensors, navigation and defensive avionics. By the 1990s, the H-6G and H-6H models appeared off the production line as pure anti-ship/cruise missile carriers, with defensive armament deleted, and wing and fuselage pylons replacing the internal weapons bay.
Despite the weapons and avionics upgrades, these variants retained the basic airframe and were still powered by a pair of WP-8 turbojets, a licence-built copy of the original Mikulin AM-3 or RD-3M that powered the 1950-vintage Tu-16.
But by the turn of the millennium, China began a program to fit new engines to the type and to bring the bomber up to date with modern avionics. The result of this protracted program is the H-6K which made its first flight in 2017.
The most significant improvement over earlier versions of the H-6 is the replacement of the elderly WP-8 engines with Russian Soloviev D-30 turbofans, similar to the Russian Ilyushin Il-76 and Chinese Xi’an Y-20 airlifter. Fitted within enlarged inlets in the aircraft’s wing roots, the D-30s give the H-6K a claimed combat radius of 3,500 kilometres, enabling the Chinese to reclassify the type as a strategic bomber and to reach out into the western Pacific.
Meanwhile, the nose section of the airframe has also been reworked, eliminating the glazed navigator’s station in favour of a powerful radar. The flight crew now have a modern glass cockpit, while the airframe has been reinforced using composite materials.
The H-6K reinstated the internal weapons bay, giving the type the ability to carry out conventional bombing missions, while a variant designated H-6J is entering service with the PLANAF. H-6M cruise missile carriers have also entered service, again without the internal weapons bay.
The most common and contemporary missile types carried by the various H-6 variants are the YJ-12 anti-ship and CJ-20 cruise missile. The former is a supersonic missile with a reported range of 400km, while the latter is a subsonic land attack cruise missile with a range of up to 1,500km.
The latest variant is the H-6N, which adds aerial refuelling capability to the H-6 with a nose-mounted refuelling probe. It also features a semi-recessed weapon bay in its belly with reports claiming it can carry the new CJ-100 supersonic cruise missile – an air-launched ballistic missile designated by the US DoD as the CH-AS-X-13 – and even the WZ-8 high-speed, high-altitude reconnaissance unmanned aerial vehicle.
Transport and tankers
For years the PLAAF’s largest airlifter was the Shaanxi Y-8, an unlicensed copy of the old Soviet An-12 Cub four-engine turboprop airlifter. Roughly analogous to older variants of the Lockheed-Martin C-130, China imported a number of An-12s from the Soviet Union in the 1960s before the Sino-Soviet split in the latter part of the decade. With the import source cut off, China decided to reverse-engineer the type.
The first Y-8 flew in 1972 and was built by the Xi’an Aircraft Corporation, with production later moving to its Shaanxi counterpart in 1975, and entering serial production in 1981. The Y-8 has since evolved into the Y-9, with both types finding additional utility for special missions such as airborne early warning, electronic and signals intelligence gathering, and long-range anti-submarine missions.
The Y-9 is a stretched, modernised Y-8, capable of carrying 25 tonnes in its main cabin – compared to the Y-8’s 20 tons – and featuring modern six-bladed composite constant-speed fully-feathering reversible propellers. The Y-9 first flew in November 2010, entering service with the PLAAF in 2012 and achieving full operational capability (FOC) in 2017.
Meanwhile, rapprochement following the end of the Cold War saw a renewal of Chinese and Russian co-operation to meet China’s needs for a strategic airlift capability. This came in the form of the Ilyushin Il-76 airlifter, with China eventually ordering 27, of which four have been converted to KJ-2000 Airborne Early Warning and Control (AEW&C) aircraft.
The transports serve with the PLAAF’s 13th Transport Division with two regiments based at Dangyang and Wuhan, in western Hubei province. They have taken part in several humanitarian assistance and disaster relief (HADR) missions in the region in recent years, including the search for missing Malaysian Airlines flight MH370 off the coast of Western Australia in 2014.
The need for an increase in strategic airlift capacity meant China’s next push was to develop its own heavy airlifter. This eventually became the Y-20, a high-wing, low-slung undercarriage airlifter, powered by four Soloviev D-30 turbofans similar to the Il-76 and H-6K. Maximum takeoff weight is reported to be 220,000kg (485,000lbs) with a maximum cargo capacity of 66 tonnes.
The Y-20 incorporated technological advances including the use of indigenously made composites in its construction. 3D-printed parts were also used elsewhere, helping speed up the production process.
Y-20s entered PLAAF service in late 2016, with the 4th Transport Division at Qinghai in China’s Western Sichuan province the first to receive the type. Production quickly ramped up and a satellite photo of Xi’an Aircraft Corporation’s production facility in Xi’an-Yanliang Airport, taken in late 2019, showed 20 airframes on-site in addition to about 10 already in service at the time.
China is also developing the Y-20 as a tanker. The PLAAF’s modest tanker fleet has been an Achilles heel as the force modernised, with just a small number of H-6 tanker versions in service. These have limited fuel capacity due to the H-6’s relatively small size. The tanker ranks were bolstered slightly in 2014 with the acquisition of three Il-78 tankers from Ukraine.
As is often the case with China, it is likely this acquisition will be used in the development of its own manufacturing and operational capabilities, with several of the Y-20s seen in satellite photos carrying what appear to be wingtip refuelling pods. China has not, however, officially admitted the existence of the Y-20 tanker, and no verifiable photos have been seen so far.
Tankers are just one of special mission types in which China has invested development effort. Using the Y-8 and more recently the Y-9 airframe, it has put into service at least 12 different types of specialised aircraft for carrying out diverse missions, ranging from electronic and signals intelligence gathering, to long-range anti-submarine warfare and psychological operations.
Each of these uniquely configured aircraft come under the ‘High New’ – or GaoXin in Chinese – code name, and each type is given a unique numerical designation after the GaoXin or GX prefix. For example, the GX-3 is a standoff electronic warfare platform based on the standard Y-8 airframe, while the newer GX-6 is an anti-submarine/maritime patrol aircraft like the Lockheed P-3C Orion, based on the Y-9 airframe in service with the PLANAF.
Several of these special mission types have actually been involved in operations in both the South and East China Seas, where the aircraft operating over the latter are regularly photographed by intercepting Japanese fighter jets.
The PLAAF also operates three different types of modern AEW&C aircraft. In Chinese service, these are referred to as the KongJing which is shortened to KJ and which directly translates as ‘Sky Watch’. The first of these is the KJ-200, a Y-8-based system which carries a dorsal ‘balance beam’ radar, similar outwardly to the Saab Erieye. Development of the KJ-200 took place in 2001, although the crash of a prototype in 2006 that killed 40 crew and engineers was a significant setback to the program.
The type eventually entered service by 2009, with aircraft assigned to the PLAAF’s 26th Special Missions Division at Wuxi in Jiangsu province, west of Shanghai. At least 10 KJ-200s are in service, although the type has since been complemented with a new AEW&C design. Based on the Y-9 airframe and designated the KJ-500, the type features a non-rotating circular radome in place of the balance beam radar, mounting an AESA radar in three separate arrays angled 120° to one other for all-round coverage.
The first KJ-500 entered service with the PLAAF in late 2014. Both the KJ-200 and KJ-500 are also assigned to the PLANAF, with that service having deployed both types of AEW&C to operate over the disputed South China Sea from bases in China’s southern island of Hainan.
In 1996 China signed a deal with Israel’s IAI for the conversion of three of its Il-76 fleet to AEW&C aircraft fitted with Israel’s PHALCON radar. The first aircraft had been converted but not delivered when intense US pressure pushed Israel to walk away from the deal in 2000. The radar and other components were removed from the aircraft before its return to China.
This forced China to develop its own KJ200 and a larger AEW&C platform called the KJ-2000. Fitted with a phased array radar arranged in a similar configuration to the later KJ-500, the first of four KJ-2000s entered service in 2005. The radar is claimed to have a maximum detection range of 470km (290 miles).
Engines and future
China’s reliance on Russian engines to power the PLAAF modernisation has always been a sticking point. An inability to reliably manufacture its own indigenous engine designs meant that China has been unable to boast of a fully indigenous military aircraft industry.
This has not been due to a lack of effort, and now a typically ambitious effort to develop its own modern aircraft engine industry to power its latest generation aircraft is underway.
At the forefront is the Shenyang-Liming WS-10 turbofan – an afterburning engine intended to replace the Russian Saturn AL-31 that powers most of China’s fleet of fighters. The WS-10 is reportedly rated at 27,000 to 31,000 lbs of thrust, but reliability and manufacturing problems have continued to dog the design throughout its extended development cycle. Despite being a mainstay of the twin-engine J-11 and J-16 fleets, starting in 2011, it is only in the past year or so that the WS-10 has found its way into production J-10s – a signal that China is finally happy enough with the engine to power its single-engine fighters.
China is also developing the more powerful WS-15 for the J-20, but production is moving relatively slowly. A recent stock exchange filing by a subsidiary of China’s Central Iron and Steel Research Institute (CISRI) revealed that production of the WS-15 will only reach between three and five units a year by 2026. Instead, production J-20s will likely continue using the WS-10 in the interim.
Imagery of test aircraft belonging to Chengdu also suggests that work in continuing on thrust vectoring versions of the WS-10, with J-10s and J-20s having been photographed with the distinctive thrust vectoring control (TVC) nozzles. The design appears to be a three-dimensional TVC nozzle which will improve the jets’ manoeuvrability in the both the vertical and horizontal axis.
Development work is also continuing on the WS-18 and WS-20 high-bypass turbofans as alternatives for the Y-20 airlifter. An Il-76 test-bed based at the PLAAF’s primary flight test unit (CISRI) in Xi’an-Yanliang airbase, has been flying with a WS-20 for a number of years, however production Y-20s are still being powered by the Russian D-30 engine. The CISRI subsidiary’s document referenced to above suggests that limited production of the WS-20 will only start in 2024, while WS-18 development is partially suspended as new manufacturing alloys are developed.
Development work on the next generation of Chinese combat aircraft is also ongoing. China is confirmed to be pushing ahead with the H-20 bomber, a new stealth type to replace the H-6. It is still not known which of China’s state-owned aircraft manufacturers will be chosen to undertake this project, although models of a potential offering have been displayed at Chinese defence shows on a number of occasions.