Japan Maritime Self Defense Force and U.S. P-3 Orion patrol craft fly over the Los Angeles-class attack submarine USS Houston (SSN 713) during a photo exercise on the final day of Exercise Keen Sword 2011.

PACIFIC OCEAN (Dec. 10, 2010) Japan Maritime Self Defense Force and U.S. P-3 Orion patrol craft fly over the Los Angeles-class attack submarine USS Houston (SSN 713) during a photo exercise on the final day of Exercise Keen Sword 2011. The exercise enhances the Japan-U.S. alliance which remains a key strategic relationship in the Northeast Asia Pacific region. Keen Sword caps the 50th anniversary of the Japan - U.S. alliance as an "alliance of equals." (U.S. Navy photo by Mass Communication Specialist 3rd Class Adam K. Thomas) File# 101210-N-6720T-221