Military Wiki

A Service Squadron (ServRon) was a U.S. Navy squadron that supported fleet combat units. Service Squadrons were used by the US Navy from their inception in 1943 to as late as the early 1980s. At the time of their inception during the second world war they allowed the US Navy to operate across the ocean for extended periods of time. During the war Service Squadrons would create a temporary forward base. A good example of one such base was at Ulithi, a small atoll in the central Pacific. Service Squadrons allowed the US Navy to do the seemingly impossible, they essentially created a major naval base at a location relatively near the area of operation. With the naval base at Ulithi to refit, repair and resupply, many ships were able to deploy and operate in the western Pacific for a year or more without returning to a major port facility such as Pearl Harbor or San Diego.[1] Among the vessels operating in service squadrons were tankers, oilers, refrigerator ships, ammunition ships, supply ships, floating docks and repair ships. They provided diesel, ordnance, aviation fuel, food stuffs and all other supplies. Equally important at places like Ulithi were the portable piers and floating dry docks which allowed a great many ships to undergo battle damage repair without having to travel the thousands of miles back to a major US naval base. To have a fully functional major port in the middle of the Pacific was a big advantage for the U.S. Navy. Ulithi was as far forward from the US naval base at San Francisco as the San Francisco base was from London, England.

The commander of the service squadron was responsible for the operation of all the ships, docks and repair yards in the squadron. The Commander was referred to as ComServRon, with the title followed by the unit designation of his Squadron, such as ComServRon 10.

Service Squadrons were slowly disbanded as fleet combat support functions were shifted to Military Sealift Command, manned by civilians in the late 1970s.

War in the Pacific

Service squadrons played a vital role in the war in the Pacific during the second world war. The Pacific ocean with its vast reaches was a significant obstacle to overcome. In considering their war in the Pacific against the United States, the Japanese had counted on the fact that the size of the Pacific Ocean would in itself be a defense. For the US Navy to conduct operations against the Japanese, all actions would necessarily be far from their home ports. Travel to the area of combat would consume the fleet's supplies of fuel and food and limit the length of time US Navy assets could operate in the Western Pacific. Japanese naval strategy ('Kantai Kessen') was built around the idea that this would present them with an opportunity to knock the US Navy out of the conflict with a single decisive action. They sought such an opportunity throughout the war.

Creation of Service Squadrons

In his planning for how the war in the Pacific would be fought and won, Admiral Nimitz knew the manufacturing might of the United States would eventually supply him with a force large enough to overcome the forces of the Empire of Japan. He referred to this future force as the 'Big Blue Fleet'. To make it effective at projecting its power, he would need to devise a way to keep it supplied and in fighting condition. The ongoing resupply of a large naval force across the vast expanse of the Pacific would require the US Navy to perform something no navy had ever accomplished before. In the autumn of 1943 Admiral Nimitz ordered the creation of two service squadrons. These two squadrons would provide mobile service to the fleet as it moved across the Pacific — with one service as fleet base while the second remained to the rear. As the fleet captured new sites the rear squadron would move to the front and act as fleet base. Commanding officer Commodore Worrall R. Carter devised the mobile service squadrons that made it possible for the Navy to create repair facilities and re-supply facilities thousands of miles away from an actual Naval port. He did this essentially by bringing the port to the Navy. Admiral Nimitz called Service Squadron 4 and Service Squadron 10 his "secret weapons".[2]

Service Squadron 4 was commissioned on 1 November 1943 with its mission being to provide logistics support to fleet operations from floating mobile bases. The squadron initially was made up of 24 vessels and had its base in the South Pacific at the Funafuti Atoll, a thousand miles west of the Solomon Islands and 1200 miles south of the Marshall Islands. The USS Cascade, under the command of Captain Samuel Ogden, was the flagship for the squadron. The command included repair ships USS Phaon and USS Vestal. The Cascade arrived at Funafuti on November 21, 1943 and remained there until February 1944. During this period Captain Worrall Reed Carter (USNA 1908), was organizing the second service squadron, Service Squadron 10. Service Squadron 10 was commissioned on 15 January 1944 at Pearl Harbor.


The Fifth Fleet at anchor at Majuro, 1944.

The Marshall Islands were considered the first major stepping stone for the battles across the Central Pacific to Japan. United States Marines were landed on January 30, 1944, but found that Japanese forces had previously evacuated their fortifications to Kwajalein and Enewetak about a year earlier. The islands that made up the Majuro atoll were secured without incident. Majuro had one of the largest natural anchorages in the Pacific. It became the first major forward base for the US Pacific fleet and was the largest and most active port in the world until the war moved westward and Majuro became supplanted by Ulithi.[3]


After the capture of Kwajalein in February 1944 the Cascade moved from Funafuti to Kwajalein. On 17 March 1944 Squadron 4 was absorbed into Squadron 10. Captain Herbert Meyer Scull (USNA 1919,) was re-assigned as Chief of Staff for Rear Admiral Hoover, Commander Forward Area, Central Pacific. Captain Samuel Ogden in the Cascade became representative "A" of Commander Service Squadron 10 in command of Kwajalein and Roi. The Cascade remained at Kwajalein until May 1944 when she moved to Eniwetok.


The United States captured Enewetak in a five-day amphibious operation in February 1944. Major combat occurred on Engebi Islet, which was the most important Japanese installation on the atoll. Combat also occurred on the main islet of Eniwetok itself, and on Parry Island, the site of a Japanese seaplane base. Following its capture, the anchorage at Eniwetok became a major forward naval base for the U.S. Navy. On 5 June Commodore Carter joined ServRon 10 at Eniwetok. His flagship was the Prairie (AD-15). The following ships were also present in July 1944: destroyer tenders Cascade, Piedmont (AD-17), and Markab (AD-21); repair ship Hector (AR-7); repair ship landing craft Egeria (ARL-8); floating drydocks ARD-13, ARD-15; mobile floating drydock AFD-15; and floating workshop YR-30. During July 1944 there were a large number of vessels present at Eniwetok. The daily average of ships present during the first half of July was 488; during the second half of July the daily average number of ships at Eniwetok was 283. By the end of July Commodore Worrall R. Carter flew to Pearl Harbor to participate in planning the move of Servron 10 facilities from Eniwetok to Ulithi. By this point in the conflict, Commander Service Squadron 10 (ComServRon 10) had several hundred ships and floating equipment under his operational control, and had the largest staff afloat in the Pacific to help administrate responsibilities.


With Sorlen island in the foreground, Third Fleet vessels crowd the north anchorage at Ulitih in late 1944.

Ulithi was perfectly positioned to act as a staging area for the US Navy's western Pacific operations.[4][5] The atoll is in the westernmost of the Caroline Islands, 360 miles (580 km) southwest of Guam, 850 miles (1,370 km) east of the Philippines and 1,300 miles (2,100 km) south of Tokyo. It is a typical volcanic atoll, with a coral reef, white sand beaches and palm trees. Ulithi's forty small islands barely rise above the sea, with the largest being only half a square mile in area. However the reef runs roughly twenty miles north and south by ten miles across, enclosing a vast anchorage with an average depth of 80 to 100 feet (30 m). The anchorage was well situated, but of course there were no port facilities to repair ships or re-supply the fleet.[6]

The survey ship USS Sumner surveyed the lagoon and reported it capable of holding 700 vessels. Service Squadron 10 was called upon to convert the lagoon into a servicable naval station. On 4 October 1944 the vessels of Service Squadron 10 began leaving Eniwetok for Ulithi.

U.S. naval forces including several Essex class carriers at anchor in Ulithi March 1945.

At Ulithi pontoon piers of a new design were built, each consisting of the 4-by-12-pontoon sections, filled with sand and gravel, and then sunk. The pontoons were anchored in place by guy ropes to deadmen on shore, and by iron rods driven into the coral. Connecting tie pieces ran across the tops of the pontoons to hold them together into a pier. Despite extremely heavy weather on several occasions these pontoon piers stood up remarkably well. They gave extensive service, with little requirement for repairs. Piers of this type were also installed by the 51st Battalion to be used as aviation-gasoline mooring piers near the main airfield on Falalop.[6]

On 8 October 1944 Commodore Worrall R. Carter's flagship the USS Prairie, the merchant ammunition ship Plymouth Victory and the USS Cascade sailed for Ulithi. The Markab initially remained at Eniwetok, leaving for Ulithi on 18 October 1944 and arriving on 22 October.

USS Iowa at a floating drydock at Ulithi.

Within a month of the occupation of Ulithi, a whole floating base was in operation. Six thousand ship fitters, artificers, welders, carpenters, and electricians arrived aboard repair ships, destroyer tenders, and floating dry docks. The USS Ajax had an air-conditioned optical shop and a metal fabrication shop with a supply of base metals from which she could make any alloy to form any part needed. The USS Abatan, which looked like a big tanker, really distilled fresh water and baked bread and pies. The ice cream barge made 500 gallons a shift.[6] The dry docks towed to Ulithi were large enough to lift dry a 45,000 ton battleship.[2] Fleet oilers sortied to and from Ulithi to meet the task forces at sea, refueling the warships a short distance from their combat operational areas. The result was something never seen before: a vast floating service station enabling the entire Pacific fleet to operate indefinitely at unprecedented distances from its mainland bases. Ulithi became the undisclosed Pacific base for the major operations late in the war, including Leyte Gulf and the Okinawa operation. The huge anchorage capacity was greater than either Majuro or Pearl Harbor, and over seven hundred ships anchored there at a time. After Leyte Gulf was secured, the Pacific Fleet moved its forward staging area to Leyte. Service Squadron 10's conversion of the lagoon at Ulithi to a major naval resupply and staging area was one of the most remarkable feats of the war.

In September 1944 the USS Ocelot arrived at Pearl Harbor to undergo conversion to flagship for Service Squadron 10.[7] The ship was fitted with extensive radio and visual signaling equipment, with radio and coding rooms in the superstructure, and berths for the squadron commander, staff officers, and enlisted men below.[8] The conversion was completed in October, and Ocelot sailed via Eniwetok for Ulithi where she spent the next six months providing an administrative post at the advanced base.[7]

San Pedro Bay, Leyte

USS Ocelot, Service Squadron 10 flag.

The movement of American forces closer to victory necessitated advancing support elements as well, and on 24 May 1945 Ocelot shifted to San Pedro Bay, Leyte[7]

Buckner Bay, Okinawa

On 13 September Ocelot again moved, to Buckner Bay, Okinawa as the forward supply followed the course of the conflict finally to the home waters of Japan. Shortly after arrival there the facilties were struck by a Typhoon, and a number of vessels were lost, including the Ocelot which was run aground and had its back broken. Command was shifted to another vessel and the job of keeping the Navy supplied continued forward.


  • Carter, Worrall Reed, Dan A Kimball and Raymond Spruance Beans, bullets, and black oil : the story of fleet logistics afloat in the Pacific during World War II. Annapolis, Dept. of the Navy, 1953.
  • Wildenberg, Thomas, Gray steel and black oil : fast tankers and replenishment at sea in the U.S. Navy, 1912-1995. Annapolis, Md: Naval Institute Press, 1996.
This article incorporates text from the public domain Dictionary of American Naval Fighting Ships.

This page uses Creative Commons Licensed content from Wikipedia (view authors).