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USS Leonard F. Mason (DD-852)

The USS Leonard F. Mason was a Gearing-class destroyer that served the U.S. Navy for over thirty years before going on to an additional twenty-two year career in the Taiwanese Navy. She was named in honor of a Marine who was posthumously awarded the Medal of Honor for extraordinary heroism during the Battle of Guam in July 1944.


Leonard F. Mason was built at the Bethlehem Steel shipyard in Quincy, Massachusetts. Her keel was laid in May 1945; she was launched the following January and commissioned six months later.

An improvement on the previous Sumner-class destroyer (which itself was based on the previous Fletcher-class), Gearing-type vessels such as Leonard F. Mason were over 390 feet in length, 41 feet in width and displaced over 2400 tons. The engines consisted of Babcock & Wilcox boilers and two geared turbines that were manufactured by General Electric or Westinghouse, depending on the shipyard. These engines were capable of propelling the vessel at speeds of up to 35 knots (roughly equivalent to 40 miles per hour). During peacetime operations, Leonard F. Mason carried a crew compliment of 11 officers and 325 seamen.

Naval History

Upon completion of shakedown trials, Leonard F. Mason was posted to San Diego. During her first years in the water, she was deployed to the Far East twice. In April 1949, a collision with the USS Fechteler resulted in a six-foot gash in the Leonard F. Mason's bow. From the end of July until October of 1950, the vessel underwent an overhaul at the Mare Island Shipyard near Vallejo, California. During this time, several weapons were replaced and/or modified.

During the Korean War, Mason made two combat tours, from May to August 1951 and again between February and September 1953.

The destroyer spent most of her career in the Pacific; at various times she was stationed out of Yokosuka, Japan, Long Beach California and NB San Diego. She was deployed to Vietnam several times between 1964 and 1973. Mason underwent her first Fleet Rehabilitation and Modernization (FRAM I) at the Boston Naval Shipyard in 1963. Mason underwent another major overhaul at Mare Island during the first five months of 1967. During most of 1970, the destroyer underwent a second FRAM conversion, which included several major weapons upgrades. Mason underwent minor maintenance at Subic Bay, Philippines in February of 1972. In December of that year, the vessel sustained minor shrapnel damage during combat action of the North Vietnamese coast. In March 1973, the Mason suffered rudder damage which required time in drydock at NB Sasebo (Japan). In September of that year, the destroyer was again damaged while at Pearl Harbor when another vessel struck her port side.

She was ultimately sold to the Republic of China (Taiwan) in 1978, where she continued to serve as the ROCS Shuei Yang (DD-26) until February 2000.

Asbestos Risk on the USS Leonard F. Mason (DD-852)

Asbestos insulation was used in many places aboard Leonard F. Mason. Most members of the crew had at least some exposure to this dangerous mineral. Those stationed in the engine room, maintaining heavy machinery, or assigned to firefighting and damage control likely had the heaviest exposure. Inhaling and swallowing of asbestos can eventually lead to a diagnosis of malignant mesothelioma.

The battle damage sustained by the USS Leonard F. Mason increased the asbestos risk to her crew. This is because asbestos materials are most dangerous when they are worn or damaged. Such materials become friable, releasing microscopic asbestos fibers into the surrounding air. Her multiple refits, repairs and overhauls also represented a significant health hazard to the sailors performing such duties.



Destroyer History Foundation. "Gearing Class"

Mooney, James. Dictionary of American Fighting Ships. (Washington DC; Department of the Navy, 1991).

N/A. "USS Leonard F. Mason: The Unofficial (But More Complete) History, 1945-Present" Updated 02 February 2011. Retrieved 23 February 2011.

N/A. "Welcome Aboard" (pamphlet, 1975). Available at

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