Helicopters fly in the formation of "70" during a military parade celebrating the 70th founding anniversary of the People's Republic of China (PRC) in Beijing, capital of China, Oct. 1, 2019. (Xinhua/Zhan Yan)
Helicopters fly in the formation of "70" during a military parade celebrating the 70th founding anniversary of the People's Republic of China (PRC) in Beijing, capital of China, Oct. 1, 2019. (Xinhua/Zhan Yan)