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Home : Media : News
NEWS | Aug. 16, 2023

Pearl Harbor Naval Shipyard completes USS Tucson availability

By Ana Maring Pearl Harbor Navel Shipyard

Pearl Harbor Naval Shipyard & Intermediate Maintenance Facility (PHNSY & IMF) successfully completed all planned maintenance and modernization work on USS Tucson (SSN 770) Aug. 15, delivering the Los Angeles-class fast-attack submarine back to the fleet.

Tucson entered dry dock at PHNSY & IMF in February 2021 for the submarine's engineered overhaul (EOH) availability. An EOH is a significant multi-year overhaul, which occurs near the mid-point of a Los Angeles Class submarine's service life. During this type of availability, the sub receives essential repairs and necessary modernization as well as routine maintenance to her systems, keeping the vessel at the forefront of the fleet and “Fit to Fight.”

“The Tucson Project/Ship’s Force team faced some initial setbacks but persevered through challenges of difficult repairs and supply chain issues,” said Devin Paiva, USS Tucson Project Superintendent. “The shipyard drove to complete an aggressive end game schedule in 267 days when the 10-year average is 350 days. Truly amazing what a professional team of experts can accomplish!”

Tucson's successful undocking last November marked a significant step towards returning to sea. Once undocked, the project team finished additional maintenance and testing requirements pier side.

Ahead of EOH’s final certification for unrestricted operations, USS Tucson’s project team and ship’s crew successfully completed sea trials ensuring the submarine can operate safely and deliver operational capability to the fleet. Successfully returning from sea trials and certifying in record time, the availability officially ended Aug. 15.

"Ship and submarine maintenance and repair is part of our national dialogue now because it is critical to our Nation's defense; returning Tucson to the fleet provides a crucial asset in the Pacific Ocean,” said Capt. Ryan McCrillis, who headed the shipyard Operations Department until June. "Submarine maintenance is extremely challenging and the need to return our ships to the fleet requires holding a tight schedule. This is a complex and challenging job and everyone who has a part of it should be rightfully proud to be part of this team.”

Tucson’s EOH required more than 440,000 man-days of production work with support from more than 800 PHNSY & IMF mechanics and engineers, Navy program offices, and contractors to complete more than 12,350 individual jobs.

"Tucson returning to the fleet highlights what can be achieved when a motivated group of personnel come together for a common purpose,” said Tucson’s Commanding Officer, Cmdr. Adam Matthews. “I commend the professionalism and dedication of PHNSY's workforce to make the EOH an overwhelming success. The Submarine Force is stronger today with Tucson back in the fight."

Commissioned in 1995, Tucson is the 59th Los Angeles-class attack submarine and the 20th of the improved Los Angeles-class attack submarines to be built. Tucson is currently assigned to Submarine Squadron 7 and homeported at the historic submarine piers in Pearl Harbor, Hawaii.

PHNSY & IMF is a field activity of NAVSEA and a one-stop regional maintenance center for the Navy’s surface ships and submarines. It is the largest industrial employer in the state of Hawaii, with a combined civilian and military workforce of approximately 6,400. It is the most comprehensive fleet repair and maintenance facility between the U.S. West Coast and the Far East, strategically located in the heart of the Pacific, being about a week’s transit time closer to potential regional contingencies in the Indo-Pacific.

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