红旗漫卷西风 (hóngqímànjuǎnxīfēng): red flags rolling in the west wind

From 毛泽东《清平乐·六盘山》(Mao Zedong, October 1935), written crossing Liupanshan at the end of the Long March: 天高云淡，望断南飞雁。不到长城非好汉，屈指行程二万。六盘山上高峰，红旗漫卷西风。今日长缨在手，何时缚住苍龙 (Sky is high, clouds are pale; I gaze until the southbound geese are gone. He who does not reach the Great Wall is no true man — counting on fingers, twenty thousand li. On Liupan's high peak, red flags roll in the west wind. Today the long cord is in my hand; when shall I bind the gray dragon?).

usage

漫卷 describes the loose, sweeping billow of a large flag — not tight furling. 西风 in classical poetry is the autumn wind, often cold and melancholy; Mao flips it into something triumphant.