U.S. troops board a U.S. Army CH-47 Chinook helicopter after completing a mission at an Afghan National Army combat outpost in Afghanistan, June 23, 2015. U.S. troops board a U.S. Army CH-47 Chinook helicopter after completing a mission at an Afghan National Army combat outpost in Afghanistan, June 23, 2015. SHARE IMAGE: Download Image: Full Size (1.86 MB) Tags: Photo Essays Photo By: VIRIN: 405840-A-YGY12-227.jpg Photo Gallery