An Aug. 25 report in Beijing-based newspaper China Aviation News praised the engine division of Xi'an-based aeronautic and aerospace firm AVIC Qingan Group. The report mentions a planned project which would see the development of China's first domestically-made turbofan-ramjet combined cycle engine, designed for an unnamed aircraft. The description of this engine suggests something resembling the Pratt and Whitney J58 variable cycle engine used by the SR-71 Blackbird.
A source close to the PLA Air Force was cited by New Outlook as stating that this is part of a project to develop a manned supersonic aircraft, currently in the preparation stages at a domestic research institute. The aircraft is expected to have a top speed faster than the Blackbird on completion, according to the source, although the project is yet to be formally launched.
The China Aviation News report stated that in the first half of 2015, the engine division of AVIC Qingan Group finished the design process for three engine products and gained approval for them in May and July.
The article went on to list descriptions of the three engines as China's first domestically developed turbofan-ramjet combined cycle engine designed for an unnamed aircraft, a classic model engine and a classic model engine with a medium bypass ratio. This suggests the latter two are improved versions of the WS-10 and WS-18 turbofan engines.
The turbofan-ramjet combined cycle engine project, however, has never before been made public. The article stated that there is no precedent for the project and that China currently has no suitable heat-resistant materials for the project and therefore will have to contract overseas suppliers, adding that without the appropriate tools, they will have to go about making them from scratch.
A PLA Air Force source told New Outlook that the aircraft that will use this engine has been in experimental development for several years by an aircraft institute in the southwest. The aim of the project is to surpass the SR-71 Blackbird with a plane that can reach speeds of almost five-times the speed of sound, which is the upper limit of a ramjet engine. For higher speeds, a supersonic combusting ramjet (scramjet) engine is necessary. The aircraft is said to be a large manned plane, with a similar design to Mikoyan's mysterious Project 301 hypersonic aircraft.
Popular Science had reported on China's most powerful aircraft engine, the WS-20. It was getting closer to finishing its tests in Feb 2015. With a power output of 14 tons, the WS-20 would replace the less powerful and less efficient Russian D-30KP, which has only 10.5 tons of thrust. The WS-20 turbofan has been flying on this Il-76 test aircraft since 2014, and it's likely that aerial testing will wrap up in late 2015.
Previously Flight Global had reported that Chengdu Aero-Engine Group may be making some progress with the 12t-thrust WS-18A. Apparently derived from the D-30-KP2, this turbofan may be a candidate for the Y-20 and the H-6K. While Galleon notes that production could have started in 2009, other sources indicate flight testing may have only begun last year.
The Pratt Whitney J58 is described here
China has had problems with materials, production and quality of its copycat jet engines
Global Security describes China's jet engine problem.
China’s problems with the copycat version of SU-27 AL-31 turbofans isn’t about advanced computerized production. The Chinese just can’t figure out the alloy composits of making a reliable heat bearing jet engine as yet. Because of this, Chinese copycat engine WS-10 of the SU-27 AL-31 turbofans tend to have blades that crack and break apart sucking debris into the engine. Chinese WS-10 also has shorter lifespans than original AL-31 turbofans because metal alloys in Chinese version reportedly break & can’t handle the high heat. Also Chinese WS-10 turbofans have ‘spooling’ issues with their copycat turbofans. It’s a lot more looming problem for the Chinese engineers than just advanced computerized production machinary. Plus the copycat WS-10 of the AL-31 is not powerful enough to allow the feature ‘super cruise’ ability of F-22, F-35, and the future PAK FA-50 joint venture stealth fighter by Indo-Russo design.
In 2013, internet photos revealed that the WS-10A engine was being used with the J-11BS, the modified version of the J-11B fitted with domestic active electronically scanned array radar and forward looking infrared system. With the capability to carry the PL-12 air-to-air missile, the J-11BS entered service with the PLA Air Force in 2007 and Navy Air Force in 2010, said the report.
In addition to the J-11BS, two of China's J-15 carrier-based fighters have been observed to be powered by the WS-10H, the upgraded version of the WS-10A.
Here is a photo from the Chinese military review blog
SOURCES - Flight global, Wantchinatimes, chinesemilitaryrview, popular science, global security