U.S. Navy Petty Officer 3rd Class Christopher Larsen mans a .50-caliber machine gun aboard a riverine command boat as it passes under Prince Khalifa Bin Salman Causeway in Bahrain during a training exercise in the Arabian Gulf, Jan. 21, 2014. Larsen is a boatswain's mate assigned to Task Group 56.7.4. U.S. Navy Petty Officer 3rd Class Christopher Larsen mans a .50-caliber machine gun aboard a riverine command boat as it passes under Prince Khalifa Bin Salman Causeway in Bahrain during a training exercise in the Arabian Gulf, Jan. 21, 2014. Larsen is a boatswain's mate assigned to Task Group 56.7.4. SHARE: Download: Full Size (2.02 MB) Tags: Photo Essays Credit: VIRIN: 031410-C-XAN82-417.jpg Photo Gallery