China has acquired 76 Su-27SK fighters from Russia since 1992, and bought a license for production of another 200 planes in 1995, in a deal worth $2.5 billion.
"Since 1996, the domestic version of the Su-27 aircraft, dubbed J-11, has been produced at the Shenyang Aircraft Corporation (SAC) with the use of Russian components," the Vedomosti newspaper said.
The licensed production of the Su-27 has given China its most capable fighter aircraft while also providing a vehicle for its industry to gain knowledge of third-generation fighter manufacturing, Vedomosti said.
About 95 aircraft had been produced in China by 2003. However, the 1995 agreement did not include the transfer of avionics and AL-31F turbofan engine technology, and the Chinese manufacturers had to rely on the Russian supply of these systems.
In 2004, China requested that Russia's Sukhoi aircraft manufacturer stop deliveries of the assembly kits, stating that the basic variant of the Su-27SK/J-11 fighter could no longer satisfy Chinese Air Force requirements.
But the Russian sources insist that China's decision was prompted by an increased share of domestic components in the assembly of the licensed aircraft and breakthroughs in engine manufacturing technology.
"The breakthrough in engine manufacturing technology allowed China to increase its share of domestically developed components and technologies from 70-75% to over 90%," the newspaper cited an official from the Russian state-controlled arms exporter, Rosoboronexport, as saying.
In 2006, China revealed first official details about the domestically developed WS-10A Tai Hang turbofan engine, similar to the Russian AL-31F engine in both technology and performance.
China announced that the engine had been successfully tested on a modified Su-27K fighter, but Russian experts believe it is not reliable enough to start the full-scale production of the aircraft.
Rosoboronexport and Chinese officials refused to comment on the latest developments in the situation regarding the licensed production of Su-27s in China.
Meanwhile, Konstantin Makiyenko from the Russian Center for Analysis of Strategies and Technologies, believes that if China manages to launch a full-scale production of the indigenous copy of the Su-27, it would easily push Russia from third-party markets, and it would be difficult to prove a violation of the license agreement.
Su-27 Flanker an its variant, Su-30 Flanker C, constitute the bulk of Russia's arms exports. Last year, Sukhoi exported 50 of these aircraft, accounting for 50% of Rosoboronexport's export revenues, Vedomosti said.
The newspaper also noted that China had a long history of copying Russian aircraft. Chinese J-6 and J-7 fighters were modeled after MiG-19 Farmer and MiG-21 Fishbed, H-6 bomber - after Tu-16 Badger, and Y-5, Y-7 and Y-8 transport planes - after An-2 Colt, An-24 Coke and An-12 Cub, respectively.