USS Cheyenne Completes First Refueling Overhaul Under U.S. Navy's Service Life Extension Program
The USS Cheyenne (SSN 773), a Los Angeles-class fast attack submarine, has completed its Engineered Refueling Overhaul (ERO) at Portsmouth Naval Shipyard and is now undergoing post-overhaul sea trials as of December 2025. This overhaul is part of the Service Life Extension Program (SLEP), which aims to restore nuclear propulsion, modernize systems, and extend the operational life of select submarines.
The Cheyenne has integrated advanced sonar and combat systems, enabling it to remain mission-capable for an additional 10 to 15 years. The U.S. Navy plans to identify up to five more Los Angeles-class submarines for similar upgrades, contingent on FY2026 budget approval.
This initiative is intended to bridge operational gaps while newer Virginia-class submarines are being produced. The Cheyenne's successful overhaul, completed ahead of schedule, underscores the Navy's focus on enhancing industrial capabilities amidst increasing global operational demands.
