Africa is becoming a major outlet for Chinese military aircraft. Nigeria and Zimbabwe have already made purchases. The Chinese aircraft are cheap, easy to maintain and suit African needs. While the Chinese aircraft are not as effective as Western, or even Russian, models, the Africans only have to worry about other African air forces. Few of these countries have first class aircraft or pilots. Most African nations use their military aircraft to keep their own populations under control, or just for prestige ("we have an air force") purposes. So the cheap and reliable Chinese aircraft are just right.
China's growing influence in Africa is the result of Chinese companies increasingly offering aggressively priced goods and services, as well as credit and no political strings. The Chinese are willing to deal with corrupt governments, and cut corners to get deals done. This gives them an edge over Western firms, which are restricted, in how dirty they can operate, by laws back home. China needs raw materials from Africa, and the Chinese business practices suit the rulers of many African countries.