Master Sgt. Ralph Chisolm transits an obstacle course. U.S. Army Master Sgt. Ralph Chisolm, of the 2nd Battalion, 18th Field Artillery Regiment, Combined Joint Task Force - Horn of Africa, transits an obstacle course in Arta Beach, Djibouti, on Oct. 18, 2008. More than a dozen service members assigned to the Combined Joint Task Force participated in an annual three-week course hosted by members of the 13th Demi-Brigade, French Foreign Legion. SHARE: Download: Full Size (0.06 MB) Credit: VIRIN: 333364-X-IFT24-374.jpg Photo Gallery