An Mk-45 five-inch .54-caliber gun is fired aboard guided-missile cruiser USS Chosin (CG 65) during a training exercise while under way in the Gulf of Aden Dec. 27, 2009.
Chosin is the flagship of Combined Task Force 151, a multinational task force established to conduct counterpiracy operations off the coast of Somalia. (DoD photo by Mass Communication Specialist 2nd Class Matthew A. Hepburn, U.S. Navy/Released). Original public domain image from Flickr