USS Isabel ( PY - 10 ) USS " Isabel " ( SP - 521 ) , later PY - 10 , was a yacht in commission in the United States Navy as a destroyer from 1917 to 1920 and as a patrol yacht from 1921 to 1946 . Construction , acquisition , and commissioning . " Isabel " was built as a private yacht in 1917 by Bath Iron Works , Bath , Maine for automobile manufacturer John North Willys of Toledo , Ohio . Willys had intended for the yacht to have qualities that would make her desirable for use by the U . S . Navy , and had contacted the Navy about the possibility of selling her into naval service . The Navy initially was uninterested . However , after the United States entered World War I on 6 April 1917 , the Navy decided to buy " Isabel " , which it viewed as being not only highly suitable for use as a patrol vessel but also having characteristics similar to those of a destroyer . The Navy therefore acquired her in 1917 prior to completion , converted to Navy use as a destroyer , gave her the patrol vessel designation SP - 521 , and commissioned her as USS " Isabel " at the Boston Navy Yard in Boston , Massachusetts , on 28 December 1917 with Lieutenant Commander Harry E . Shoemaker in command . Service in World War I . " Isabel " departed on 28 January 1918 for France via Bermuda and the Azores . She reached Brest , France , on 20 February 1918 to begin convoy escort duties . While performing coastal convoy duty , she fought German submarine s on four occasions . The first time was on 18 March 1918 , when at 10 : 50 hours , while proceeding westward and escorting stores ship USS " Rappahannock " ( AF - 6 ) and transport USS " President Grant " ( ID - 3014 ) , she and destroyer USS " Reid " ( DD - 21 ) spotted a German submarine off Penmarc ' h , France . " Reid " fired on the submarine and dropped two depth charge s , while " Isabel " dropped one depth charge . Although the two ships were credited with sinking the submarine , evidence gathered later indicated that the submarine had escaped . Her commanding officer , Lieutenant Commander Shoemaker , received the Navy Cross " for distinguished service . . . as commanding officer of . . . " Isabel " , engaged in the important , exacting and hazardous duty of transporting and escorting troops and supplies through waters infested with enemy submarines and mines . " He was relieved by Lieutenant Lewis W . Comstock on 24 July 1918 . " Isabel " continued protecting convoys carrying troops and supplies to France until the end of the war and departed France on 16 December 1918 . Post - World War I service 1919 - 1920 . Arriving at Boston , Massachusetts , on 2 January 1919 , " Isabel " remained inactive at Philadelphia , Pennsylvania , until 25 April 1919 , when she was ordered to Key West , Florida , to report to the commanding officer of submarine USS " K - 5 " ( SS - 36 ) for duty as a tender to ships on the Mississippi River . Departing Key West on 14 May 1919 , " Isabel " steamed up the Mississippi to St . Louis , Missouri , stopping at every major port on the river along the way to perform recruiting duties for the Navy . Returning to New Orleans , Louisiana , on 20 August 1919 , " Isabel " was soon underway for Rockaway Beach , Long Island , New York , for duty as a tender for the famous flying boat s of the NC - 4 flotilla . Reporting 18 September 1919 , she cruised the United States East Coast with the aircraft from Maine to Florida before returning to Rockaway Beach on 4 January 1920 . " Isabel " decommissioned at Philadelphia 30 April 1920 . Out of commission 1920 - 1921 . While " Isabel " was out of commission , her classification was changed from " destroyer " to " patrol yacht " , and , under the Navy ' s new alphanumeric hull classification system instituted in 1920 , her designation changed from SP - 521 to PY - 10 on 20 July 1920 . Meanwhile , the Navy considered how best to employ her in the future . One idea was to convert her into a seaplane tender to support the NC flying boats ; another was to send her to Constantinople in the Ottoman Empire to replace the gunboat USS " Scorpion " ( PY - 3 ) as station ship there . In the end , it was decided to send her to the Far East and employ her on the Yangtze Patrol . Two of her 3 - inch ( 76 . 2 - millimeter ) single - purpose guns were removed and replaced by two 3 - inch ( 76 . 2 - millimeter ) 23 - caliber antiaircraft guns . The Yangtze Patrol 1921 - 1928 . Recommissioning at Philadelphia on 18 July 1921 , " Isabel " departed for the Far East on 21 August 1921 to join the Yangtze Patrol on the Yangtze River . Transiting the Panama Canal , she arrived at Hong Kong on 7 November 1921 . She became flagship of the patrols commander , Rear Admiral William H . G . Bullard . She was further modified at Cavite Navy Yard in Cavite , Luzon , the Philippines , having a deckhouse installed aft . During the tumultuous years that followed in China , " Isabel " served as a member of the patrol and as its flagship , charged with protecting American commerce from pirates . Based at Shanghai , " Isabel " spent the low - water period on the river at Hankow , returning to the coast in the summer . She and the other small gunboats of the U . S . Navy in China performed the arduous task of protecting American interests during numerous incidents and threats to American nationals . On many occasions the ship came under fire , as in October 1926 when she was caught between the rifle fire of opposing Chinese armies on the Yangtze . " Isabel " also took part in the Nanking Incident on 24 March 1927 , when shelling and threats of force procured the release of a large group of American and British prisoners held by Chinese nationalists in Nanking . She patrolled the 1 , 700 nautical miles ( 3 , 148 kilometers ) of this dangerous river until 1928 , when enough purpose - built river gunboats had arrived to serve in the Yangtze Patrol that she was no longer needed on the river . She then joined the Asiatic Fleet . Asiatic Fleet duty 1928 - 1941 . Her aft deckhouse removed , " Isabel " spent 1928 through 1941 with the Asiatic Fleet in the Philippines and China , much of the time at Manila as " relief flagship " for the fleet commander . In the 1933 - 1934 gunnery year , she finished first among patrol vessels mounting 3 - inch ( 76 . 2 - millimeter ) 50 - caliber guns . In December 1941 , as the threat of war with Japan grew ever larger , " Isabel " was given a secret mission by President Franklin D . Roosevelt to make a reconnaissance of the coast of Japanese - occupied French Indochina . Personally briefed on the plan by Asiatic Fleet commander Admiral Thomas C . Hart , " Isabel " s commanding officer , Lieutenant John W . Payne Jr . , took her to sea on 3 December 1941 , with all excess topside weight removed and her motorboat replaced by a pulling whaleboat , heavily fueled and provisioned , carrying additional life rafts , and with all of her codebook s except for one prearranged cipher left ashore . She left Manila under a cover story that she was searching for a PBY Catalina flying boat missing off the Indochinese coast . Payne was under orders to approach the coast under the cover of darkness , showing lights that would mislead observers to think that she was a fishing vessel , and report on Japanese ship movements ; if forced to fight , he was to fight back as best he could and try to escape , but , if necessary , to destroy " Isabel " rather than allow the Japanese to capture her . " Isabel " first sighted another ship on 5 December 1941 , when she encountered a large , dark - gray ship flying no flag and apparently altering course frequently to try to move out of sighting range . On the morning of 6 December 1941 , a Japanese Aichi E13A 1 " Jake " reconnaissance floatplane from the seaplane tender " Kamikawa Maru " circled " Isabel " at an altitude of 1 , 000 feet ( 305 meters ) and a range of 2 , 000 yards ( 1 , 830 meters ) . She was in sight of Cam Ranh Bay , French Indochina , later that day when she was ordered to return to Manila . While she was on her return voyage , she received word on 8 December 1941 ( which was 7 December 1941 in the United States and at Hawaii ) , of the Japanese attacked Pearl Harbor and the beginning of U . S . participation in World War II . World War II service . " Isabel " s first wartime duty was to escort U . S . Navy submarines through the minefields off Corregidor as they sortied from Manila Bay to defend the Philippines . She was at Cavite Navy Yard when Japanese aircraft made a devastating attack on the base on 10 December 1941 . Eight bomb s , all duds , ringed " Isabel " s fantail . She shot down one of the attackers . For the next month " Isabel " operated as an antisubmarine escort for convoys in the East Indies , as outnumbered American , British , Australian , and Dutch forces tried desperately to oppose the Japanese offensive . She underwent air raids at Batavia on Java , Palembang on Sumatra , and Tjilatap on Java , escaping from several ports only days ahead of invading Japanese forces . On the way back from a convoy assignment on 7 February 1942 , " Isabel " was sent to rescue survivors from the Dutch merchant ship " Van Cloon " , which had been sunk by torpedo es and gunfire from a Japanese submarine , near Surabaya , Java . As " Isabel " picked up 187 survivors of " Van Cloon " , the Japanese submarine which had sunk " Van Cloon " , probably " I - 55 " , fired a torpedo at " Isabel " and surfaced nearby . The torpedo missed , and " Isabel " quickly drove the submarine down with gunfire and assisted a patrolling Dutch Catalina flying boat in dropping depth charges to drive it from the area . One of the last American ships to leave Java before the island fell to the Japanese , " Isabel " arrived in Australia on 7 March 1942 after seeing gunboat USS " Asheville " ( PG - 21 ) sunk during numerous Japanese air raids on the ships south of Java during the voyage to Australia . Based at Fremantle in Western Australia , " Isabel " took up new duties as escort and training ship for the U . S . Navy submarines now also based there , serving as a target for submarines practicing torpedo approaches . She also helped train allied submarines . " Isabel " remained on this duty until 27 August 1945 , twelve days after hostilities with Japan ceased . " Isabel " received one battle star for World War II service Post - World War II service . " Isabel " had been considered for post - war service as flagship for the Philippine Sea Frontier , but the United States Seventh Fleet commander deemed her to be in too poor condition for such use . Instead , she departed Fremantle on 27 August 1945 and Australia entirely on 5 September 1945 , headed for the United States . She called at Port Moresby , New Guinea ; Manus Island ; Majuro ; Johnston Island ; and Pearl Harbor , Hawaii , before arriving at San Francisco , California , on 26 October 1945 . Decommissioning and disposal . A month later , a Navy inspection team deemed " Isabel " to be in such poor condition that she should be decommissioned , towed to sea , and sunk . She was decommissioned on 11 February 1946 and struck from the Navy List on 26 February 1946 , but rather than being sunk , she was sold for scrap on 2 March 1946 . Scrapping began on 25 March 1946 .