United States Navy reserve fleets

The United States Navy maintains a number of its ships as part of a reserve fleet, often called the "Mothball Fleet". While the details of the maintenance activity have changed several times, the basics are constant: keep the ships afloat and sufficiently working as to be reactivated quickly in an emergency.

In some cases (for instance, at the outset of the Korean War), many ships were successfully reactivated at a considerable savings in time and money. The usual fate of ships in the reserve fleet, though, is to become too old and obsolete to be of any use, at which point they are sold for scrapping or are scuttled in weapons tests.

In rare cases, the general public may intercede for ships from the reserve fleet that are about to be scrapped – usually asking for the navy to donate them for use as museums, memorials or artificial reefs.

In November 1976, the controlling organization was the Inactive Ship Division of the Naval Ship Systems Command. Since 2004, the administrative organization is called the Navy Inactive Fleet. As of 2011, the controlling organization actually appears to be the Inactive Ships Management Office of the Program Executive Officer - Ships, Naval Sea Systems Command, Portsmouth, Virginia.

Merchant ships held in reserve are managed as part of the separate National Defense Reserve Fleet within MARAD (US Maritime Administration). Several of its sites, such as at Suisun Bay in California, are also used to store regular Navy ships.

Ships placed in the reserve fleets are categorized depending on priority, funding and the planned disposition.

Category B Ships in this category are prioritized over the other categories when it comes to maintenance and funding. They are retained for possible future mobilization and will receive updates and upgrades as funding permits.

Category C These are ships that will be maintained as-is; meaning no updates or improvements unless funding becomes available after that assigned for category B ships has been exhausted.

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