The US Navy’s fourth Nimitz-class aircraft carrier, USS Theodore Roosevelt (CVN-71), has completed nearly 50% of its scheduled planned incremental availability (PIA) this year at Naval Air Station North Island, US.

More than 146,000 man hours have been spent so far in upgrading and repairing aircraft catapults, propulsion plants, tanks, voids, piping, insulation, berthings, aircraft elevators, fire main valves, decks, and bulkheads of the aircraft carrier.

The PIA is conducted after approximately every 36 months on the ship to upgrade and fix the damage that the vessel suffers during its deployment at sea.

"While a bit more than that 50% of the work is behind us, there still a significant volume of work remaining."

USS Theodore Roosevelt commanding officer captain Craig Clapperton said: "This availability is the largest work package ever attempted in San Diego in a six-month period, and we have experienced some significant additional growth work due to the scope and complexity of the work.

“However, due to great teamwork, innovative problem solving and the cooperation of the entire maintenance and engineering communities, we are still scheduled to finish the availability before the holiday curtailment and meet our timeline."

Additional enhancements include upgrading the ship’s computer network from an Integrated Shipboard Network System (ISNS) to a Consolidated Afloat Network Enterprise System (CANES).

Using more than 1,000 computers, 200 printers and 3,000 user accounts, a large amount of data has been migrated to the upgraded system under the supervision of the ship's automated data processing officer Nathan Bell.

Clapperton added: "While a bit more than that 50% of the work is behind us, there still a significant volume of work remaining.

"Further, ship's force must now turn a significant portion of our efforts and focus to training and preparing for our work-up cycle.”

Commissioned in 1986, the 317m-long aircraft carrier is equipped with three Raytheon GMLS Mk29 eight-cell launchers for Nato Sea Sparrow surface-to-air missiles. It can accommodate more than 6,000 personnel and can operate at a speed of more than 30k.

Image: USS Theodore Roosevelt undergoing PIA at San Diego, US. Photo: courtesy of US Navy photo by Mass Communication Specialist 3rd Class Paul L. Archer/Released.