Defensive Perimeter Soldiers provide security creating a defensive perimeter after uploading from a CH-47 Chinook helicopter during air assault training exercise at Fort Drum, New York, Feb 21, 2018. Army photo by Staff Sgt. James Avery SHARE: Download: Full Size (1.63 MB) Tags: Northcom, Northern Command, Soldiers, Army, training Credit: Staff Sgt. James Avery VIRIN: 180221-A-FJ979-548A.JPG Photo Gallery