USS Slater - Destory Escort Historical Museum



Modifications of Destroyer Escorts

APDDestroyer escorts proved to be highly versatile ships, capable of accomplishing a wide variety of missions. This versatility, combined with the abundance of available destroyer escorts due to the vast expansion of American shipbuilding during the war, meant that many destroyer escorts were converted both during and after World War II into two new types of ships: high speed transports (APDs) and radar picket ships (DERs). Although originally designed only as convoy escorts, the modified destroyer escorts soon proved themselves more than capable of filling their new roles.


DEs & APDsWorld War II, especially in the Pacific, was an amphibious war. Every invasion began with soldiers and Marines assaulting beaches from landing craft. Experience had shown that beach obstacles and mines were a serious hazard to any invasion force. To remove these threats, the Navy formed Underwater Demolitions Teams known as "Frogmen." These sailors, the predecessors to today's Navy Seals, were tasked with landing ahead of the main force to destroy obstacles and clear paths for invading troops. What the UDT teams lacked were a vessel that could transport them quickly to their assigned beaches and then cover them as they did their work. The Navy took many of its old four piper destroyers, as well as many BUCKLEY and RUDDEROW class destroyer escorts and converted them into new high speed transports known as APDs. These ships sacrificed much of their armament for expanded berthing spaces and the ability to carry four Higgins landing craft on their upper decks. The APDs proved successful not only as transports, but also as convoy escorts and as rescue ships. For example, DE APDs CECIL J. DOYLE, BASSETT, DUFILHO and RINGNESS rescued 250 survivors after the USS INDIANAPOLIS was sunk on 30 July 1945. Of the ninety-three DEs converted to APDs, only the USS RUCHAMKIN survives today, as a museum ship in Columbia.


Radar picket ships were also developed as a result of lessons learned in the Pacific. The kamikaze onslaughts of the Okinawa campaign proved to the Navy the need for an early warning system for its fleets. The stopgap measure of throwing destroyers, destroyer escorts and other small ships into far flung picket stations worked, but at the cost of 36 ships sunk, over 300 damaged and 5,000 sailors' lives. The Navy experimented with several BUCKLEY class DEs by adding more powerful radar equipment at the expense of armament, but the ships proved unsuccessful. However, the onset of the Cold War and the threat of Soviet nuclear missiles forced the Navy to try again. This time, thirty-four EDSALL class DEs and two JOHN C. BUTLER class ships were converted in a similar fashion to the APDs, but with more radar equipment added instead of space for troop berthing. These ships were then placed on patrol in the Atlantic and Pacific Oceans as part of the Distant Early Warning (DEW) Line. Newly classified as Destroyer Escort Radar Picket ships (DERs), they soon found themselves on long, lonely patrols constantly alert for Soviet aggression. DERs stationed in the Atlantic spent a month at a time sailing in the some of the worst weather on the planet. Once the DEW Line was replaced by satellites, the DERs were sent to Vietnam to serve as interdictors to Viet Cong resupply efforts. The DERs were the longest-lived of the World War II destroyer escorts, with several remaining in service with the US Navy until the early 1970s.

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