USS Trepang SSN-674 — Arctic UAP Photographs

The USS Trepang (SSN-674), a Sturgeon-class nuclear attack submarine, was operating in the Arctic Ocean in March 1971 on a joint mission with naval personnel and an unidentified civilian passenger under Admiral Dean Reynolds Sackett Jr.'s command. A series of photographs were taken from the bridge showing large disc-shaped and elongated craft near the sea surface and partially submerged under arctic ice. The photographs show multiple craft from different angles, some appearing to be in the process of transitioning between water and air. The images were classified SECRET upon their creation. Researcher John Greenewald of The Black Vault obtained multiple photographs through FOIA requests; naval historians and photographic analysts verified the photographs as authentic US Navy documentation from the period. The photographs show an object with a flat disc profile approximately 40–50 feet in diameter with a raised dome. In several frames the object appears to be at the water surface or partially submerged, consistent with the class of transmedium UAP later formally acknowledged by the US Navy in AARO documentation. The circumstances of the mission — a nuclear submarine with a classified civilian passenger — have not been fully explained in released records. The photographs are among the few government-authenticated images showing apparent transmedium UAP activity.