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All Things Navy on Twitter: "Vice Adm. G. Ashok Kumar, Indian Navy Vice Chief of Naval Staff, (center) looks through a periscope simulator at Submarine Training Facility San Diego... https://t.co/9gAjpyKkpb" / Twitter
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File:US Navy 090513-N-5013K-062 Vice Adm. Tohru Izumi, commander in chief, Self-Defense Fleet, Japan Maritime Self-Defense Force (JMSDF), uses the periscope aboard USS Seawolf (SSN 21).jpg - Wikimedia Commons
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Cmdr. Michael Grubb, left, commanding officer USS Newport News (SSN 750) and Chief Master Sgt. Harold L. Hutchison, right, command Senior Enlisted Leader for North American Aerospace Defense Command (NORAD) and United
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