Z-10 attack helicopters attached to an army aviation brigade of the PLA 72nd Group Army lift off from a snow-covered military airfield for a flight training exercise on January 30, 2018. (eng.chinamil.com.cn/Photo by Zhang Huanpeng)

A Z-10 attack helicopter attached to an army aviation brigade of the PLA 72nd Group Army flies at an ultra-low altitude during a flight training exercise on January 30, 2018. (eng.chinamil.com.cn/Photo by Zhang Huanpeng)