This is the 4.5-generation multirole version which uses more Chinese components, including radar, engine, and missiles. China is interested in reducing its reliance on foreign technology for both cost reasons and a desire to improve its domestic research and design. It is reported that one regiment of J-11Bs are currently in service, but this seems to contradict with the latest information provided by the Chinese government: In May, 2007, the existence of J-11B was finally acknowledged by the Chinese government for the first time when the state-run Chinese TV stations first aired the report on J-11B in PLAAF service, which were subsequently publicized in various domestic Chinese media such as state-run websites and newspapers (like Xin Wen Hua Bao, New Culture Newspaper). However, the official Chinese report claims that there are only two squadrons of J-11Bs in service, instead of a regiment, which is consisted of three squadrons (as of end of 2007). According to the Chinese report, which is agreed by some western sources such as Jane's Information Group, the J-11B is superior to Su-27SK in the following areas:
The wide adoption of composite material (mainly carbon fiber) for the surfaces, reducing the weight of the aircraft for more than 700 kg, while the life of the composite part is increased over 10,000 hours in comparison to the original part built from steel.
Redesigned air inlets of engine intakes to reduce the radar cross section, this coupled with the adoption of composite material, and application of radar absorbent material has reduced the radar cross section (RCS) of 15 square meters of Su-27SK to just >3 square meters of F-16 A/B.
Full air-to-surface / sea capability is added and J-11B is able to launch various precision guided air-to-surface and air-to-sea munitions.
Certified to be equipped with WS-10 (will be upgraded to WS-10A in the future) turbofan engine, which is claimed to be cheaper to operate than AL-31F.
Incorporation of on-board oxygen generating system (OBOGS): With the exception of Su-35 and Su-37, J-11B is the first of the Flanker family to incoporate such technology. Due to the adoptation of western style design features such as fully digitized computerized controls and solid state micro-electronics, Chinese claimed that the domestic OBOGS is superior than the analog system Russia offered to China.
Improved radar. The new radar is able to track 6-8 targets at the same time, and engage 4 of the 6-8 tracked simultaneously. When used against large surface target such as a destroyer, the maximum range of the radar was in excess of 350 km. The range against aerial targets was not disclosed, but it would be definitely much shorter, as in all radars. The Chinese official report claims that the radar is better than the 147x/KLJ-X radar family, but stop short of identifying the exact type. Contrary to many erroneous comments by many domestic Chinese sources, which mistakenly claimed that the radar had adopted a passive phased array antenna, the official claims of many Chinese governmental sources such as technical journals and publications have revealed that the radar still adopted a slotted plannar array antenna.
Fully digitized solid-state avionics has replaced the analogue one in Su-27SK. In the mid-2007, the Chinese governmental television station CCTV-7 released news clips of Chinese pilots in the cockpits of J-11B, with the LCD of glass cockpit of J-11B clearly visible, despite that the official report itself only claimed replacing the original avionics with domestic Chinese fully digitized solid-state avionics, and nothing of EFIS or glass cockpit was mentioned. In comparison to the earlier EFIS on J-11A, the most obvious difference is that LCD MFDs on J-11B are aligned in a straight line, instead of the middle one being slightly lower. The arrangement, appearance and layout of MFDs and EFIS of J-11B are similar to the general design concept of the west.
Missile Approach Warning Systen
Though it has long been rumored that J-11B is aerial-refueling capable, it was impossible to determine if any aerial refueling probes have been added to the aircraft from the released official reports by the Chinese government. Professor Wang also revealed in the same interview that the J-11B entering series production would be equipped with domestic engines.