The LSD MSMO was developed to provide extended dry docking, modernization, upgrades, and repairs to the LSD-41 Whidbey Island and related LSD-49 Harpers Ferry Classes of amphibious landing ships, which were commissioned between 1985-1998. The classes are highly similar, but the slightly larger Harpers Ferry Class reduces the number of onboard LCAC hovercraft from 4 to 2, in exchange for more cargo capacity. Two ships of these classes are being upgraded each year through 2013, and the last ship will be modernized in 2014. LSD MSMO aims to keep all 12 remaining ships of these classes in service and mission-capable to 2038.
These 186-190m, 14,460-14,850 tonne US Navy LSD ships are designed to carry Marines and equipment close to shore, then land them by launching onboard craft from their well decks. They’re similar in size to the earlier Austin/Cleveland Class LPDs, but are much smaller than either the new LPD-17 San Antonio Class, or the carrier-size LHA-1 Tarawa and LHD-1 Wasp Classes. Despite these characteristics, or perhaps because of them, their flexibility and numbers have made them among the US Navy’s most-used ships for several years running.