"The US Navy’s large nuclear carriers need to be refueled at an interval of about every ten to fifteen years.
Since refueling is an involved process requiring the removal a significant amount of deck plating the ship typically undergoes a complete overhaul at the same time.
This takes about a year and means that the ship and it’s crew are placed into living a different kind of life while the ship occupies the drydock.
...The US Navy has made this wonderful documentary of the USS Nimitz in drydock while undergoing the ROH process.
This is a big project for a big ship.
This is not a refueling overhaul, which typically done at Newport News, still it’s a year of refit and rebuilding..."
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