PNSY Successfully Undocks Cheyenne 2025-02-10 Comments Closed News, RSS KITTERY, Maine — The Los Angeles improved-class attack submarine USS Cheyenne (SSN 773) was successfully undocked Feb. 6, marking a significant milestone in its service life extension program at Portsmouth Naval Shipyard. Related Items Gen. Dan Caine sworn in as chairman of the Joint Chiefs of Staff 2025-04-14 Pacific Partnership 2025 Concludes Successful Mission in Virac, Philippines 2025-06-26 Pentagon cuts back F-35 upgrades to slow schedule slips: Auditors 2025-09-03 NTAG Mid America XO Enlists Son into Navy [Image 1 of 4] 2024-10-25