What type of ship is designated as AO?

The designation "AO" refers specifically to a Fleet Oiler. Fleet Oilers are vital components of naval logistics, as they are responsible for providing fuel to ships at sea, allowing naval forces to extend their operational range and maintain a continuous presence. This ability to refuel vessels on the move significantly enhances the striking power and endurance of naval fleets during operations.

By fulfilling this crucial logistical function, Fleet Oilers ensure that naval ships can remain on station longer without having to return to port for fuel, thus keeping them operational and ready for various missions. Their design emphasizes large fuel capacities and the ability to transfer fuel quickly and safely to other vessels, which is essential for maintaining the operational tempo of a fleet.

The other designations mentioned do not correspond to "AO." An Ammunition Ship, for example, is designated with an "AE," and a Combat Stores Ship indicates logistical support with a "AE." In contrast, a Logistics Support Ship usually denotes a vessel dedicated to broader logistical support roles, including supplies and equipment, but is not specifically categorized under the "AO" designation focused on fuel supplies.