Afghan National Army (ANA) commandos with the 3rd Company, 7th Special Operations Kandak fire at targets to check the accuracy of their nighttime aiming devices March 11, 2013, in Washir district, Helmand province, Afghanistan. The ANA commandos and their coalition forces mentors trained together to increase combat effectiveness. (DoD photo by Sgt. Benjamin Tuck, U.S. Army/Released)

F-16 Fighting Falcons demonstrate an ‘Elephant Walk’ as they taxi down the flightline at Kunsan Air Base, South Korea, Dec. 14, 2012. The Elephant Walk was a demonstration of U.S. and South Korean air force capabilities and strength. The F-16 Fighting Falcons are from the 35th and 80th Fighter Squadrons of the 8th Fighter Wing, Kunsan AB, South Korea; the 4th Fighter Squadron of the 388th Expeditionary Fighter Wing at Hill Air Force Base, Utah; and the 38th Fighter Group of the Republic of Korea air force. (U.S. Air Force photo/Staff Sgt. Jonathan Fowler)

A U.S. Air Force C-17 Globemaster III aircraft lands at Nellis Air Force Base, Nev., as three F-15C Eagle aircraft assigned to the 48th Fighter Wing at Royal Air Force Lakenheath, England, hold short of the runway during exercise Red Flag 13-3 Feb. 25, 2013. Red Flag is an advanced aerial combat training exercise held four to six times a year to train pilots from the U.S., NATO and other allied countries for real combat situations. (DoD photo by Lawrence Crespo, U.S. Army/Released)

The Malaysian tugboat VOS Apollo, front, prepares for defueling operations near the grounded mine countermeasures ship USS Guardian (MCM 5) while a U.S. Navy small boat, right, approaches with a salvage team on the Tubbataha Reef in the Sulu Sea Jan. 24, 2013. The U.S. Navy contracted with the VOS Apollo to assist with removing fuel from the Guardian, which ran aground Jan. 17. No fuel leaked during the grounding, and all of the approximately 15,000 gallons aboard the Guardian were safely transferred to the tugboat. (DoD photo by Naval Aircrewman 3rd Class Geoffrey Trudell, U.S. Navy/Released)

U.S. Marines with the 3rd Battalion, 4th Marine Regiment participate in Integrated Training Exercise (ITX) 3-1 at Twentynine Palms Marine Corps Base, Calif., Jan. 22, 2013. The ITX provided predeployment training for Marines. (DoD photo by Staff Sgt. Stephany Richards, U.S. Air Force/Released)

An F/A-18C Hornet aircraft assigned to Marine Fighter Attack Training Squadron (VMFAT) 101 flies over the flight deck of the aircraft carrier USS George H.W. Bush (CVN 77) in the Atlantic Ocean Jan. 24, 2013. The George H.W. Bush conducted training and carrier qualifications in the Atlantic Ocean. (DoD photo by Mass Communication Specialist 3rd Class Kevin J. Steinberg, U.S. Navy/Released)

U.S. Soldiers assigned to 3rd Brigade Combat Team, 1st Infantry Division, drive through the desert in M2 Bradley Infantry Fighting Vehicles during Decisive Action Rotation 13-03 at the National Training Center, Fort Irwin, Calif., Jan. 19, 2013. The Decisive Action Rotations were geared toward an adaptive enemy in a complex environment. (DoD photo by Sgt. Eric M. Garland II, U.S. Army/Released)

U.S. Marine Corps MV-22 Osprey aircraft with Marine Medium Tiltrotor Squadron (VMM) 161 land at a forward operating base in Afghanistan Dec. 24, 2012, as the commandant and sergeant major of the Marine Corps visit deployed troops over the Christmas holiday. (DoD photo by Master Sgt. Brenda Varnadore, U.S. Marine Corps/Released)

A U.S. Army UH-60 Black Hawk helicopter with Alpha Company, 5th Battalion, 101st CombatAviation Brigade conducts an engine run-up in the falling snow of a winter storm at Bagram Airfield in the Parwan province of Afghanistan on Dec. 27, 2012. DoD photo by Sgt. Duncan Brennan, U.S. Army. (Released)