USS Marathon ( PGM - 89 ) USS " Marathon " ( PGM - 89 / PG - 89 ) was an acquired by the U . S . Navy for the task of high speed patrolling in shallow waterways . The second ship to be named " Marathon " by the Navy , " PGM - 89 " , a motor gunboat , was laid down 21 June 1966 by Tacoma Boatbuilding Co . , Tacoma , Washington ; reclassified " PG 89 " on 28 March 1967 ; launched 22 April 1967 ; sponsored by Mrs . Robert W . Copeland ; and commissioned 11 May 1968 , Lt . L . W . Waterman in command . A specially - designed littoral combat ship . Designed for shallow water coastal operations , " Marathon " was built for speed and maneuverability . Constructed almost entirely of aluminum and fiberglass , the ship ' s light weight and gas turbine engines made the patrol gunboat well suited for counterinsurgency and coastal blockade operations . Given the guerilla tactics in the Vietnam War , as well as the danger to larger ships posed by small missile boats , the " Asheville " - class patrol gunboats were seen as a relatively cheap " littoral combat ship . " Vietnam War operations . After commissioning , " Marathon " operated independently in Puget Sound for several weeks prior to proceeding to San Diego , California , for further operations and training . Following shakedown operations and individual type training , " Marathon " prepared for " Operation Market Time " coastal surveillance operations off Vietnam . On 28 August , Rear Admiral Elmo R . Zumwalt , ( prospective Commander , Naval Forces , Vietnam ) , rode the ship during a patrol problem to gain insight into the gunboat ' s capabilities . In November , the gunboat entered Long Beach Naval Shipyard for a short post - shakedown availability , a period lengthened by labor and material problems to 5 March 1969 . Later that month , " Marathon " was visited by Secretary of the Navy John H . Chafee . Less than a month later on 15 April , " Marathon " suffered an engine casualty and more delays as yard workers had trouble welding the gunboats ' aluminum deck plates . After repairs were completed in May , the ship finally went to sea for a group exercise in June 1969 , where she practiced convoy defense tactics during Exercise " Bell Call . " She was also visited by Rear Admiral Dybdal , for a tour and evaluation of PG - type ships for the Ethiopian Navy . The gunboat remained at San Diego , until October when she entered Long Beach Naval Shipyard for her first major overhaul . With repairs and modifications complete in late November , began a long series of evaluations and inspections in preparation for a Vietnam deployment . A new home port in Guam . Following a tactical exercise in January 1970 , and coastal interdiction training in March , " Marathon " departed San Diego on 2 June for her new home port at Guam in the Marianas Islands . After a quick refueling stop at Pearl Harbor , the gunboat arrived at Apra Harbor , Guam on 25 June . A week later , " Marathon " sailed for Vietnam and , after a refueling stop at Subic Bay , Philippines on 8 July , she began " Market Time " duties out of Cam Ranh Bay on the 11th . Dangerous river patrols . One of " Marathon ' s " first tasks was to escort battle damaged from the mouth of the Bo De River back to Cam Ranh Bay on 15 July . The rocket - propelled grenade ( RPG ) and bullet scars in " Canon ' s " hull were sober reminders of the dangers the gunboats faced in littoral waters . After receiving a camouflage paint scheme , " Marathon " spent the next nine weeks conducted uneventful river operations before conducting a few coastal surveillance patrols in October . Relieved by other patrol gunboats , " Marathon " , and their base ship sailed to Guam , via Subic Bay , arriving there on 18 November . Operation Market Time patrols . Following a restricted availability in Guam , " Marathon " returned to Vietnam in late April 1971 , beginning " Market Time " patrols on the 27th . This monotonous cruising was interrupted in late June by a port visit to Bangkok , Thailand , 28 June to 1 July , before the gunboat returned to Cam Ranh Bay to resume patrols . " Marathon " fired her guns only once , shelling An Thoi Island on 6 August with unknown results , before arriving home to Guam on 14 September . Once there , " Marathon " began her second major overhaul , which finished up on 8 December . In a change of pace , the gunboat conducted a short security patrol of the Caroline Islands in mid - December . " Marathon " returned to Vietnam on 10 March 1972 and operated out of Yung Tau conducting maritime patrols . These operations were again uneventful and the gunboat received a well - deserved week - long visit to Singapore in late July . After a few more weeks on patrol , the gunboat returned home , arriving in Guam on 30 August . She spent the remainder of the year conducting type training and providing submarine torpedo target services . Visiting local areas in the Far East . In January 1973 , " Marathon " and " Gallup " conducted a joint week - long patrol in the Caroline Islands before resuming type training out of Guam . Local operations continued until early March , when the gunboat sailed to Subic Bay for coastal patrol operations in the Philippines . On 30 April , " Marathon " moved on to Hong Kong for a week - long port visit . After a short return trip to Subic Bay , the gunboat sailed north to Taiwan for a visit and demonstration cruises . " Marathon " then returned to Guam , arriving there on 5 June to commence another overhaul . With yard work finished in September , the gunboat resumed local operations , including two more patrols in the Caroline Islands . Underway 13 February 1974 , " Marathon " and other gunboats sailed to the Philippines and conducted a simulated missile boat attack on the battle group off Subic Bay on the 19th . Unlike the other two gunboats , " Marathon " avoided the defensive carrier air assets and successfully " launched " missile attacks against the carrier and one escort . Four days later , the gunboat sortied from Subic Bay for another exercise but a turbine compressor failure took her out of the exercise . Local repairs kept " Marathon " in port until March , when the gunboat prepared for Exercise Multiplex 1 - 74 , a combined gunboat - aircraft attack exercise on a carrier battle group . While at sea on 18 April , however , Marathon suffered a fuel leak and fire in the turbine spaces that burned into the crew spaces , forcing the ship to shut down her engines . Towed into port the following day , the gunboat was drydocked in " AFDL - 10 " for repairs . Return to the States . Following post - repair sea trials , " Marathon " and the other gunboats at Guam returned to the United States , arriving in Chicago , Illinois , on 12 November after a long , circuitous transit via Pearl Harbor , San Diego , the Panama Canal , Norfolk , Virginia , the St . Lawrence Seaway and the Great Lakes . Once there , the gunboats helped train reservists as part of Coastal River Division 21 . The gunboats also supported Navy recruiting efforts and made numerous port visits to small ports on Lake Michigan , including Traverse City , Michigan , and Milwaukee , Wisconsin . In company with and , " Marathon " got underway on 1 June 1976 for her new home port back in Little Creek , Virginia . The gunboats sailed out through the Great Lakes and the St . Lawrence River , visiting Quebec en route , before arriving in Little Creek via Newport , Rhode Island , on 25 June . Following a series of local operations , and one short visit to New York City , the ship received notification in November of her upcoming inactivation . Decommissioning . " Marathon " was decommissioned at Portsmouth , Virginia , on 31 January 1977 and was struck from the navy list that same day . The ship was demilitarized and transferred to the Massachusetts Maritime Academy on 18 April 1977 .