 Complete the following phrase:  Fenghuangshan Airport, also known as Chungsing Chang, Fenghwangshan and Makiashipen was built under the directives of Sichuan warlord Liu Xiang in 1931 for his fledgling air force operations, and was integrated into the centralized operations of the Chinese Nationalist Air Force as the War of Resistance-World War II was starting with the invasion and occupation by the Empire of Japan; Fenghuangshan served as an operations base for Chinese fighter squadrons during the 