Two Su-27 fighter jets are ready to take off for an exercise during a visit by US Admiral Mike Mullen, chairman of the Joint Chiefs of Staff, at the PLA Air Force base in Jining, East China's Shandong province, July 12, 2011. [Photo/tp.chinamil.com.cn]

US Admiral Mike Mullen (right), chairman of the Joint Chiefs of Staff, visits the PLA Air Force base in Jining, East China's Shandong province, July 12, 2011. [Photo/tp.chinamil.com.cn]