Demise
By the end of the 1950s, it was clear that boats would soon be superseded by amphibious tractors (LVTs) and helicopters for landing combat assault troops. These could not be supported by attack transports in the numbers required, and new categories of amphibious ships began to replace APAs throughout the 1960s. By 1969, when the surviving attack transports were redesignated LPA (retaining their previous numbers), only a few remained in commissioned service. The last of these were decommissioned in 1980 and sold abroad, leaving only a few thoroughly obsolete World War II era hulls still laid up in the Maritime Administration's reserve fleet. The APA/LPA designation may, therefore, now be safely considered extinct.
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