The US Navy has received the aircraft carrier USS Carl Vinson from Northrop Grumman following a complex overhaul that could extend the carrier’s life by 25 years.

The Nimitz-class carrier has undergone a reparation procedure that included work on more than 2,300 compartments, hundreds of system upgrades and over 20 million man-hours of work for defueling and refueling the nuclear reactors.

Northrop accomplished the three-and-a-half year upkeep project at the company’s shipbuilding facility in Newport News, Virginia.