Su-27S fighters in formation at Airshow China 2012 in Zhuhai, November. (File photo/CNS)
Russia has finally approved the sale of 48 advanced Su-35BM fighters to China after several years of negotiations on issues related to confidentiality of technical data.
The Su-35BM is the most advanced derivative of the Su-27S series, has a more robust airframe that allows as many as 6,000 flight hours along with better maneuverability and improved reliability.
It has been reported that China hopes to obtain the aircraft's 117S engine, designed by Russian firm NPO Saturn, for use in its air force and navy.
It is still unclear whether China would get the fully overhauled electric equipment. However, Russia displayed its brand new 117S engines in November at Airshow China in Zhuhai, indicating the two countries have reached a tacit agreement regarding the sale.
Russia is currently trying to use every means at its disposal to prevent China from producing unauthorized copies of its military products, including a Chinese version of the Russian Su-37 fighter.
Despite Sino-Russian military cooperation, China is in an awkward position owing to its practice of reverse engineering Russian technology. For instance, the J-11 and J-15 used by China are reverse engineered versions of a Russian airframe.
Moscow decided against selling China 48 of the "fourth-plus-plus generation" Su-35s, worth more than US$4 billion, after Beijing formally requested the aircraft last year as it fears China will reverse engineer its aircraft systems. China is reluctant to sign a binding clause prohibiting it from producing unlicensed copies of Russia's weapon systems.
The country has been producing unlicensed clones of Russian fighters for some time now, earlier developing a two-seat fighter bomber version of the J-16 and a Su-33 lookalike J-15, while trying to replicate a Su-33 prototype sourced from Ukraine.
However, China has asserted the fighter's design is entirely indigenous and that only the shape of the aircraft is similar to the Russian aircraft.
So far, China is yet to successfully produce any engine with only Chinese engineering and continues to procure the methods and techniques used for engine production from elsewhere. Meanwhile, engine exports have generated handsome profits for Russian arms manufacturers.