USS Oceanographer (AGS-3) (1942) - "The Green Gremlin"

Would you like to see USS Oceanographer (AGS-3) (1942) Implemented into the US Coastal Tree?
  • Yes
  • No

0 voters

How should USS Oceanographer (AGS-3) (1942) be implemented?
  • Tech Tree Ship
  • Premium Ship
  • Event Ship
  • Battlepass Ship
  • Squadron Ship
  • I said no in the previous question

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What BR should USS Oceanographer (AGS-3) (1942) be implemented at?
  • 1.0
  • 1.3
  • 1.7
  • 2.0
  • 2.3
  • Other (please explain)
  • I said no in the first question

0 voters

(Photo Caption: USS Oceanographer (AGS-3) moored in San Pedro, California before her decommissioning in 1944)

This is a suggestion for USS Oceanographer (AGS-3), a patrol ship that partook in both the First and Second World Wars. The ship was initially constructed as a yacht under the name Corsair III for the American industrialist J. P. Morgan. This suggestion will cover the ship in her 1942 configuration when she was requisitioned into United States Navy service for the second and last time in her career. This ship would be an interesting little ship to have in the U.S. Coastal Tree, owing to its impressive armament and equally exciting history. As a bonus, she would most likely be one of the sleekest ships in-game, if not the most elegant.



Corsair III was the third of four yachts built for the industrialist J. P. Morgan. She followed Corsair I which was previously sold off for merchant service and Corsair II, which also served in the U.S. Navy during the Spanish American War and WWI as the Gunboat USS Gloucester. Corsair III was in service to the Morgan Family from 1898 to 1917 and from 1920 to 1930 when she was donated to the United States Coast and Geodetic Survey (Now known as the U.S. National Geodetic Survey) for use as a Survey ship. She served as a survey ship until 1942 when she was transferred to the U.S. Navy for service in the Second World War. Initially, she was converted into a Patrol Gunboat as USS Natchez (PG-58); however, due to her age and relatively poor condition, she was, after several months of service, re-designated USS Oceanographer (AGS-3). She would serve the role of an Auxiliary Gun Boat until 1944, when due to her deteriorating condition, she was decommissioned and, by the original donation agreement, sold for scrap.



For the History of USS Corsair (SP-159) please see the suggestion for that ship which can be found here: USS Corsair (SP-159) (1917) - Suggestions / Naval - War Thunder — official forum

It has often been said that the life of a ship is usually 20-35 years, and often, the ships that stay in service longer are considered lucky. The ship that would become USS Oceanographer (AGS-3) was no exception to this saying. The ship began life as the Yacht Corsair III, which saw service in the U.S. Navy during the First World War as USS Corsair (SP-159). Following the war’s end, Corsair III would serve the Morgan Family again from June 1919 until January 1930. By this point, the ship was over 32 years old and was beginning to show its age. J.P Morgan Jr with this in mind had already decided by 1927 to order and build a new yacht that would be much larger, faster, and even more luxurious than Corsair III. This new yacht was to be the fourth and final member of the Corsair series of Yachts, and she would be aptly named Corsair IV. As for Corsair III, she would begin a new life as a Survey ship in January 1930.

USC&GS Oceanographer (OSS-26)

(Photo Caption: USC&GS Oceanographer (OSS-26)while in service to the United States Coast and Geodetic Survey)

No longer needing the older Corsair III, J.P Morgan Jr decided to donate the yacht to the United States Coast and Geodetic Survey (now the U.S. National Geodetic Survey) for use as a survey ship. This donation would occur on 2 January 1930, several months before the new Corsair IV would be launched. Following the donation of the ship, the former Corsair III was renamed USC&GS Oceanographer (OSS-26). She was named after the Oceanographer, a type of researcher studying the branch of science that deals with the sea’s physical and biological properties and phenomena.

Oceanographer would undertake many unique and exciting research voyages over the next two years as part of her role as a survey ship. During these voyages, she would discover and assist in discovering many new species of underwater fauna and several new locations, including several underwater canyons. Two of these canyons would be named after the former yacht in honor of her service United States; these canyons are aptly named Corsair Canyon and Oceanographer Canyon. She would also discover the Continental slope between the Georges Bank and Cape Hatteras. Aside from this, the ship would also go on to support the study of Geophysics and would be used by the scientist Maurice Ewing for his reflection profiling experiments in 1935. Oceanographer would also be used as a major communications ship during the 1933 Chesapeake-Potomac Hurricane alongside fellow USC&GS ships USC&GS Lydonia (CS-302) and USC&GS Gilbert. Following an exciting first few years in service, the rest of her career as a United States Coast and Geodetic Survey ship went by relatively quietly.

(Photo Caption: USC&GS Oceanographer (OSS-26) moored inboard of an unknown vessel in February 1936)

This relatively quiet service life would continue until early 1942, when following the Japanese attack on Pearl Harbor on 7 December 1941 and the subsequent declaration of war on Japan. The U.S. Navy once again began to requisition ships for military service; Oceanographer was one of these ships. On 8 April 1942, Oceanographer was called up for service and was ordered by the US Navy to report for immediate refit and conversion into a Patrol Gunboat.

(Photo Caption: USC&GS Oceanographer (OSS-26) underway in 1940, note the enlarged bridge)

USS Oceanographer (AGS-3)

When the United States entered WWII, it immediately found itself with a major shortage of small patrol ships. Thus, just as it had done during the First World War, the U.S. Navy requisitioned scores of civilian ships or even civilian vessels that had been interred from various belligerent powers. Most of the United States Coast and Geodetic Survey vessels were among those requisitioned and taken over by the U.S. Navy. The then USC&GS Oceanographer (OSS-26) was one of these vessels. Upon her entry into the U.S. Navy, service plans were immediately drawn up and put into motion to convert her into a Patrol Gunboat under the name USS Natchez (PG-58).

As part of this refit, she would be armed with two single 3"/50 Caliber Dual Purpose guns, three 20mm Oerlikon A.A. guns, and an assortment of ASW weaponry. The refit itself would only last from April to May 1942, however in a twist of ironic fate, the U.S. Navy, upon further inspection of the ship in May of 1942 following the completion of the conversion, found that Natchez was actually in very poor material condition, and due to this, she was deemed unfit for service as a Patrol Gunboat. Following this inspection, the U.S. Navy decided to instead complete the ship’s refit as an armed survey ship. With this in mind, USS Natchez (PG-58) was renamed and commissioned as the USS Oceanographer (AGS-3).

(Photo Caption: USS Oceanographer (AGS-3) in August 1942 following her conversion into an Armed Survey Ship)

The major problems that the Navy found soon made very apparent to her new crew. These problems ranged from her boilers breaking down constantly, to the decks and superstructure leaking when she took waves; this was coupled with a low steaming radius and an inability to maintain the ship’s fresh water supply. Despite these issues, the U.S. Navy deployed her to the Solomon Islands, where she partook in the campaign as a Survey ship and was painted in a distinct green camouflage; due to this camouflage, the ship was assigned the moniker “The Green Gremlin” by the sailors who saw her. Following the campaign, the Oceanographer would return stateside for a refit in Mid-1943 and continue to operate as a survey ship.

By 1944 however, her condition had drastically deteriorated, and she was, as such, in need of significant refit and repair work; she was thus ordered to San Pedro, California, where the U.S. Navy inspected her. This inspection revealed many more serious problems, which led the U.S. Navy to declare the Oceanographer beyond all economic repair. Therefore, it was recommended that she be sold for scrap. On 18 July 1944, CINPAC agreed with this recommendation and had her decommissioned without replacement in September 1944. Following this, the venerable yacht was sold for scrap in October 1944, fulfilling the original donation contract with JP Morgan’s terms, thus ending the saga of the ship known as Corsair III.

(Photo Caption: USS Oceanographer (AGS-3) Moored in San Pedro California before her decommissioning in 1944)

Specifications: USS Oceanographer (AGS-3) (1942)


General Specifications
Displacement 1,963 tons
Length 293 ft (89 m)
Beam 33 ft (10 m)
Draft 17 ft (5.2 m)

Propulsion: Two triple expansion Steam Engines, two double-ended Scotch boilers, two screws
Speed 14.7 knots (27.2 km/h; 16.9 mph)

Crew Complement:
Complement: 146


Primary Armament:
2 x 1 3”/50 Dual Purpose guns

Secondary/Anti-Aircraft Armament:
3 x 1 20mm Oerlikon AA Guns

ASW Weaponry
2 x Depth Charge Rails

Additional Photos


(Photo Caption: USC&GS Oceanographer (OSS-26) underway in the 1930s)

(Photo Caption: USC&GS Oceanographer (OSS-26) moored next to an unidentified ship at Norfolk, Virginia, on 25 February 1936)

(Photo caption: USS Oceanographer (AGS-3) in August 1942 looking forward from her aft, note the 3"/50 gun and the 20mm AA gun)

Text Sources


USA 20 mm/70 (0.79") Oerlikon Marks 1, 2, 3 and 4 - NavWeaps
USA 3"/50 (7.62 cm) Mark 10, 17, 18, 19, 20, 21 and 22 - NavWeaps
USN Ships–USS Corsair (SP-159), later USS Oceanographer (AGS-3) (
Oceanographer (
USS Oceanographer (AGS-3) (
USS Oceanographer (AGS-3) - Wikipedia

Image Sources


Survey Ship Photo Index (AGS) (
USS Oceanographer (AGS-3): Photographs (
USS Oceanographer (AGS-3) - Wikipedia