China is apparently happy with the Russian Su-27. China has bought at least 72 of these aircraft in the last seven years, as well as giving the Russians hundreds of millions of dollars for the right to manufacture Su-27s in China. But a complex aircraft like the Su-27 requires a steady stream of high tech spare parts and equipment fixes and upgrades. The research and development (R&D) for the Su-27 is still done in Russia, and apparently the Chinese are supplying all of the money to keep it going. But now the Russian Air Force is also buying Su-27s (which it couldn't afford many of since 1991), and will be getting some of the new Su-27IB fighter-bomber version in 2005. China was the top weapons importer last year, buying $3.6 billion. In the last seven years, China has imported over $18 billion in weapons, mainly from Russia.