U.S. forces to hand over 159 military helicopters to Afghanistan by 2021

A Black Hawk helicopter flies during a handover ceremony from the U.S. forces to the Afghan air force in Kandahar Province, south Afghanistan, Oct. 7, 2017. The U.S. forces has planned to hand over 159 military helicopters to the Afghan air force by 2021, an Afghan government official said. (Xinhua/Sanaullah Seiam)