USS Oceanographer (AGS-3)

USS Oceanographer (AGS-3) was a survey ship of the United States Navy during World War II that produced charts chiefly of passages in the Solomon Islands area of the Pacific Ocean. Upon transfer to the Navy, she had initially been named and classed as gunboat USS Natchez (PG-85). Before her World War II Navy service, she had been USC&GS Oceanographer (OSS-26), a survey ship with the U.S. Coast and Geodetic Survey from 1930.

From her launch in 1899 to 1930, she had been Corsair, a private steam yacht of American industrialist J. P. Morgan, Jr., except for a brief period during World War I. During that conflict, the United States Navy chartered her as patrol vessel USS Corsair (SP-159). She accompanied the American Expeditionary Force to France in 1917 and largely patrolled off the west coast of that country.

After putting in for needed repairs in June 1944, Oceanographer, after further inspection, was instead decommissioned in September and broken up for scrap.

World War I
Corsair was built in 1899 by W. & A. Fletcher Co., Hoboken, New Jersey; chartered by the Navy 15 May 1917; commissioned the same day, Lieutenant Commander T. A. Kittinger in command; and reported to the Atlantic Fleet.

Corsair sailed from New York 14 June 1917 with the first contingent of the American Expeditionary Force to France, arriving at Saint-Nazaire 27 June. On 2 July she stood out to join the U.S. Patrol Squadrons operating against enemy submarines and performing escort and patrol duties off the west coast of France. She crossed the war zone many times on convoy escort, and rescued survivors of torpedoed vessels. On 17 October 1917, she assisted the torpedoed United States Army transport USAT Antilles, picked up many of her survivors, and searched for the submarine which had attacked her. On 22 June 1918, she rescued the survivors of Navy cargo ship USS Californian, which had struck a mine, and adding to her outstanding rescue record, between 12 and 14 September, towed the disabled Norwegian steamer Dagfin into Verdon.

Corsair cleared Brest 18 November 1918, for operations in British waters, calling at Rosyth, Scotland, and Queenstown, Ireland, serving from time to time as flagship for Commander, U.S. Naval Forces in European Waters. She put in at Plymouth 7 May 1919 to embark Secretary of the Navy Josephus Daniels and his staff for transportation to Brest, sailing with them 8 May and arriving the same day. The dignitaries disembarked 9 May, and Corsair sailed the next day for New York by way of the Azores and Bermuda, arriving 28 May. Corsair was returned to her owner 9 June 1919, once again becoming the private yacht Corsair II.

United States Coast and Geodetic Survey career
The United States Coast and Geodetic Survey acquired Corsair II on 2 January 1930 and placed her in service as the survey ship USC&GS Oceanographer (OSS-26). She operated along the United States East Coast until transferred to the U.S. Navy on 7 April 1942 for World War II service.

World War II
Oceanographer was acquired by the Navy from the Coast and Geodetic Survey at Norfolk, Virginia on 7 April 1942, briefly renamed Natchez (PG-85); renamed Oceanographer (AGS-3); rerigged and outfitted at Norfolk Shipbuilding and Drydock Co. for survey duty; and commissioned 15 August. Work was completed 28 August and Comdr. Henry B. Campbell, USCGS, assumed command, with Lt. Comdr. Myron W. Graybill, USN, as Executive Officer.

After shakedown in the Chesapeake, Oceanographer steamed for New York 3 October to join a convoy en route to Cristóbal, Canal Zone. She transited the Canal, and at San Pedro, California, reported for duty to CINCPAC. Upon completion of repairs at San Pedro, she got underway for Seattle. She encountered a severe storm off Astoria, Oregon, necessitating further repairs at Winslow Marine Railway Co., Bainbridge Island, Washington. Proceeding to Kodiak via the Inside Passage, she reported to the Alaskan Command with no sound or radar gear, a very short cruising radius, and limited potable water capabilities, considered generally unsuitable for Aleutian duty.

Oceanographer returned to Seattle 25 December 1942 for additional repairs. After towing an aircraft transportation lighter from Seattle to San Francisco, she was assigned to the Matson Navigation Co. for repairs. Comdr. Graybill assumed command 2 March 1943 and the following day Oceanographer got underway for Pearl Harbor, where sound gear was installed and necessary alterations made.

The survey ship departed Pearl Harbor escorting several LSTs and plotted a course for Nouméa, New Caledonia. As her first war zone assignment she surveyed Havannah Passage, New Caledonia. Upon completion of the Havannah Passage charts the ship made three other surveys in the vicinity of Nouméa, erecting numerous beacons and planting many buoys. On 1 November she proceeded to Guadalcanal via Espiritu Santo to produce charts of that island's northern coast. She also surveyed Munda Bar and neighboring anchorages at Munda, New Georgia, British Solomon Islands. At various times submarine chasers and APCs assisted in the surveys and dispatched triangulation parties to islands in the vicinity.

During her sixteen months in the South Pacific, Oceanographer produced fifteen charts, each requiring from one to three million soundings. Much of the data compiled was the first of any accuracy for the area, and it contributed greatly to the success of many amphibious operations.

Ordered to Pearl Harbor 3 June 1944 for badly needed repairs, she was sent on to San Pedro, California 27 June. Upon completion of arrival inspection, it was decided to decommission and scrap her. Oceanographer decommissioned 22 September, was struck from the Navy Vessel Register 14 October, and, in accordance with the agreement executed with J. P. Morgan, Jr., broken up for scrap.