Helicopters fly in the formation of "70" during celebrations marking the 70th anniversary of the founding of the People's Republic of China (PRC) in Beijing, capital of China, Oct. 1, 2019. (Xinhua/Zhang Jiayang)
Helicopters fly in the formation of "70" during celebrations marking the 70th anniversary of the founding of the People's Republic of China (PRC) in Beijing, capital of China, Oct. 1, 2019. (Xinhua/Zhang Jiayang)