In 2002 China started work developing an improved variant of the J-11A. In 2004 China stopped production of the J-11A after 100 were produced. The J-11A used older Russian technology that was deemed unfit for China’s desire to make the J-11 series a multirole aircraft. The new J-11B would have improved radar, a glass cockpit, new engines and would be capable of carrying new modern weapons. The Chinese company Shenyang Aircraft Corporation J-11B aircraft was first set for a 2007 delivery but problems with the new China made WS-10A engines delayed delivery until 2009.
The greatly improved version of the Su-27, the J-11B entered service in 2000 with more composite materials, modern avionics, a better fire control system and new turbofan-10B engines. Most J-11B nose cones are black but the new J-11BG wears a grayish-white cone. It is thought that there is a new active phased array radar that can detect targets at a greater range and angle. The J-11BG can be armed with the Thunderbolt 10 and 15 missiles as well as PL-15 long-range Air To Air missiles.