The People's Liberation Army air force is the third-largest in the world. It consists of nearly three-quarters of a million men and approximately 5,000 combat aircraft, yet despite these numbers it suffers from a distinct lack of technology and quality equipment (though 22 state-of-the-art Su-27 Flankers were acquired from Russia in 1992). Its overall combat capability is not impressive, and is focused primarily on the defense of Chinese airspace.