PLA warplanes in ultra-low altitude flight training(1/8)

A PLA Air Force warplane in an ultra-low altitude flight training in a valley, April 25, 2019. (Photo/81.cn)

A PLA Air Force warplane in an ultra-low altitude flight training in a valley, April 25, 2019. (Photo/81.cn)

A PLA Air Force warplane in an ultra-low altitude flight training in a valley, April 25, 2019. (Photo/81.cn)

A PLA Air Force warplane in an ultra-low altitude flight training in a valley, April 25, 2019. (Photo/81.cn)

A PLA Air Force warplane in an ultra-low altitude flight training in a valley, April 25, 2019. (Photo/81.cn)

A PLA Air Force warplane in an ultra-low altitude flight training in a valley, April 25, 2019. (Photo/81.cn)

A PLA Air Force warplane in an ultra-low altitude flight training in a valley, April 25, 2019. (Photo/81.cn)

A PLA Air Force warplane in an ultra-low altitude flight training in a valley, April 25, 2019. (Photo/81.cn)