Fleet Rehabilitation and Modernization

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For the electronic memory technology, see Ferroelectric RAM. For other uses, see Fram (disambiguation).

The Fleet Rehabilitation and Modernization (FRAM) program of the United States Navy extended the lives of World War II-era destroyers by shifting their mission from a surface attack role to that of a submarine hunter.

The program was started by Admiral Arleigh Burke as a response to estimates that the Soviets would have a force of about 300 modern fast-attack submarines by 1957. The US Navy was unable to produce enough frigates to counter this threat, given other priorities such as new cruisers and aircraft carriers, so Burke instead looked for ways to modify the existing destroyer fleet which were rapidly becoming outdated anyway.

In order to provide the ships with a credible anti-submarine weapon, the FRAM upgrade centered on the addition of two new weapon systems, the ASROC rocket-assisted torpedo launcher with a range of 1-5 miles, and the DASH antisubmarine helicopter with a range of up to 22 miles. Both were armed with the new Mark 44 homing torpedo, which was also carried in torpedo tubes on the ships.

There were three different sets of FRAM upgrades. During refitting in the early 1950's, FRAM I Fletcher class destroyers gave up No. 2, 3 and 4 5-in/38 gun mounts. A trainable Mark 15 Hedgehog mount took the place of No. 2 gun, connected to a new, enlarged sonar suite. All topside 21" torpedo tubes were removed and replaced with 2 tubes mounted in the after deckhouse. 2 3-in/50 cal mounts were placed aft, atop the after deckhouse. FRAM II changes saw the replacement of the Hedgehog mount with a Mark 108 ASW rocket launcher, the addition of 2 x 3 18" Mark 44 ASW Torpedo tubes and the removal of the 3-in guns for DASH hangar and flight deck.

Ships from the Gearing class were completely torn down and rebuilt from the hull up, including new engines, a much larger combat information center, and new sonar and radar systems. The 21-inch torpedo tubes between the funnels were removed, and the 8-round ASROC battery placed there instead. The rear 3-inch/50 cal twin gun mount was removed, and that space used for the DASH's hangar and flight deck, with two new triple-tube launchers for the 18-inch Mk.44's placed just behind the rear funnel. This modernization was designed to extend the life of the destroyer by at least eight years.

Ships in the Sumner class received only armament modifications, and not all ships of the class received the FRAM upgrades. Although the rear deck was also converted as a flight deck, the new torpedo tubes were placed where the older 21" ones had been, and ASROC was not installed. The converted Sumner's were designed for another five years of service.

All classes came in for FRAM II refits starting about 1959, being rotated out of service in order to keep as many ships at sea as possible. The upgrades were complete in the early 1960s, and most of the ships involved continued to serve until the late 1960s.