Shenyang WS-10

 The Shenyang Liming WS-10 (or WS10, WS stands for Woshan, Chinese: 涡扇, meaning turbofan), codename Taihang, is a turbofan engine designed and built in the People's Republic of China. The WS-10A is already being used to power the J-11B and the J-16; eventually it will be used to power the Chengdu J-10 aircraft that currently feature Russian Saturn AL-31FN turbofan engines.

The WS-10 project had its roots in the earlier WS-6 turbofan, which was abandoned at the start of the 1980s. Development of the WS-10 started in 1987 by Shenyang Aeroengine Research Institute (606 Institute) of the China Aviation Industry Corporation and was based upon the core of CFM International CFM56 engines imported from the United States in 1982. This core itself deriving from the F16's GE F101 engines. The original WS-10 was found to lack the performance needed for modern jet-powered fighters and was never used to power an aircraft. The design was modified and an improved version, the WS-10A, was tested on a prototype Shenyang J-11 fighter in 2002.
 
In 2005 it was reported that, according to Russian sources familiar with China's WS-10A turbofan development project, WS-10A was being developed to be slightly more powerful than the Saturn/Lyulka AL-31. The sources noted that China was encountering problems with meeting weight reduction goals for the WS-10A's primary and secondary compressors and had problems meeting thrust requirements. It was also stated that Chinese thrust vectoring technology was under development for the WS-10A. The Chinese media also reported in 2005 that the WS-10A had completed 4 months endurance testing and the engine was later certified for production in 2006.

According to an interview publicised in January 2007 with J-10 pilot Li Cunbao (李存宝), the J-10 had not yet been equipped with the domestic WS-10 engine, because although the WS-10 could match the performance of its Russian counterpart (the AL-31), there was a serious drawback; the WS-10 took longer to "spool up", i.e. there was a delay in reaching the same thrust output as the Russian engine.
WS-10A is reported to have 13,200 kilograms (29,100 lb) of thrust and a 7.5:1 thrust-to-weight ratio, making it comparable to the AL-31F turbofan. The WS-10A was first displayed in public at the 2008 Zhuhai Air Show. The WS-10A design consists of a 7-stage high pressure compressor, short annular combustor with air blast atomizer and air film cooling blades. It is the first production turbofan from China to feature single crystal nickel-based turbine blades, which allow higher intake temperatures and greater engine thrust. WS-10A has also been equipped with a FADEC (full authority digital engine control) system. An asymmetric thrust vector control (TVC) nozzle, similar to the TVC nozzle of the Russian AL-31F-TVN engine, has also been reported undergoing testing.

On 2 April 2009, the director of AVIC (Aviation Industry Corporation of China) Lin Zuoming (林左鸣), stated that there were problems with the quality control procedures on the WS-10A production line, meaning the Taihang turbofan was still of unsatisfactory quality. He said that solving these problems would be a key step. In addition to poor build quality, the engines suffered from poor reliability, the Chinese engines have been lasting 30 hours at a time vs 400 for the Russian originals. Despite AVIC's issues with quality control, mass production of the WS-10 series engines would contribute significantly in improving Chinese industrial capabilities.
 
The overall situation had steadily improved by the end of 2009, after which the WS-10A had reportedly proved mature enough to power the J-11B Block 02 aircraft. By late 2013, the improved WS-10A engine has reached a new level of maturity and performance, it powered the J-16 throughout its entire flight test program and now the J-16 is starting to reach IOC and begin small batch production.

Derivatives of the WS-10 are under development, such as a high-bypass turbofan variant for propelling large transport aircraft and marine gas turbine variant for propelling ships. The high-bypass turbofan is called WS-20 which is derived from the WS-10A's core to power the Y-20 strategic transport currently under development by XAC.

A thrust-vectoring variant with higher thrust (132 kilonewtons (30,000 lbf)), called the WS-10B, is in testing and is ready for combat aircraft installation, while an even further upgrade with higher thrust (155 kilonewtons (35,000 lbf)), designated the WS-10G, was also under testing.

Variants:
WS-10 – original design producing a thrust of 126 kilonewtons (28,000 lbf)
WS-10A – improved variant producing a thrust of 130 kilonewtons (29,000 lbf)
WS-10B – upgraded variant producing a thrust of 135 kilonewtons (30,000 lbf)
WS-10G – upgraded variant producing a thrust of 155 kilonewtons (35,000 lbf) with Thrust Vectoring and stealthy nozzles that have jagged edges and tiles
WS-20 – derived variant with high-bypass ratio and none afterburner to power the Y-20 transport. 138 kilonewtons (31,000 lb)

Specifications:
WS-10A
Type: Afterburning turbofan
Diameter: 950 millimetres (37 in) inlet
Dry weight: 1,630 kilograms (3,590 lb)
Compressor: 3 fan and 9 compressor stages
Combustors: annular
Turbine: 1 high-pressure and 2 low pressure stages
Maximum thrust: 132 kilonewtons (30,000 lbf) with afterburner
Bypass ratio: 0.78:1
Turbine inlet temperature: 1750 K (1,477 °C (2,691 °F))
Thrust-to-weight ratio: 7.5