A U.S. Marine Corps CH-46E Sea Knight helicopter, foreground, and a CH-53E Super Stallion helicopter, both with Marine Medium Helicopter Squadron 364, 15th Marine Expeditionary Unit, fly over Arta Beach, Djibouti, en route to the amphibious assault ship USS Peleliu in the Gulf of Aden during a training exercise Dec. 18, 2012. The 15th MEU was deployed with the Peleliu Amphibious Ready Group as a U.S. Central Command theater reserve force supporting maritime security operations and theater security cooperation efforts in the U.S. 5th Fleet area of responsibility.